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-rw-r--r--kernel/bpf/bpf_inode_storage.c6
-rw-r--r--kernel/bpf/bpf_iter.c2
-rw-r--r--kernel/bpf/bpf_lru_list.c7
-rw-r--r--kernel/bpf/bpf_lsm.c12
-rw-r--r--kernel/bpf/btf.c107
-rw-r--r--kernel/bpf/cgroup.c127
-rw-r--r--kernel/bpf/core.c108
-rw-r--r--kernel/bpf/cpumap.c46
-rw-r--r--kernel/bpf/devmap.c4
-rw-r--r--kernel/bpf/disasm.c43
-rw-r--r--kernel/bpf/hashtab.c4
-rw-r--r--kernel/bpf/helpers.c12
-rw-r--r--kernel/bpf/inode.c13
-rw-r--r--kernel/bpf/preload/Makefile5
-rw-r--r--kernel/bpf/preload/iterators/iterators.c2
-rw-r--r--kernel/bpf/stackmap.c145
-rw-r--r--kernel/bpf/syscall.c16
-rw-r--r--kernel/bpf/task_iter.c267
-rw-r--r--kernel/bpf/trampoline.c77
-rw-r--r--kernel/bpf/verifier.c1124
20 files changed, 1570 insertions, 557 deletions
diff --git a/kernel/bpf/bpf_inode_storage.c b/kernel/bpf/bpf_inode_storage.c
index 2f0597320b6d..6639640523c0 100644
--- a/kernel/bpf/bpf_inode_storage.c
+++ b/kernel/bpf/bpf_inode_storage.c
@@ -125,8 +125,12 @@ static int bpf_fd_inode_storage_update_elem(struct bpf_map *map, void *key,
fd = *(int *)key;
f = fget_raw(fd);
- if (!f || !inode_storage_ptr(f->f_inode))
+ if (!f)
+ return -EBADF;
+ if (!inode_storage_ptr(f->f_inode)) {
+ fput(f);
return -EBADF;
+ }
sdata = bpf_local_storage_update(f->f_inode,
(struct bpf_local_storage_map *)map,
diff --git a/kernel/bpf/bpf_iter.c b/kernel/bpf/bpf_iter.c
index 5454161407f1..a0d9eade9c80 100644
--- a/kernel/bpf/bpf_iter.c
+++ b/kernel/bpf/bpf_iter.c
@@ -287,7 +287,7 @@ int bpf_iter_reg_target(const struct bpf_iter_reg *reg_info)
{
struct bpf_iter_target_info *tinfo;
- tinfo = kmalloc(sizeof(*tinfo), GFP_KERNEL);
+ tinfo = kzalloc(sizeof(*tinfo), GFP_KERNEL);
if (!tinfo)
return -ENOMEM;
diff --git a/kernel/bpf/bpf_lru_list.c b/kernel/bpf/bpf_lru_list.c
index 1b6b9349cb85..d99e89f113c4 100644
--- a/kernel/bpf/bpf_lru_list.c
+++ b/kernel/bpf/bpf_lru_list.c
@@ -502,13 +502,14 @@ struct bpf_lru_node *bpf_lru_pop_free(struct bpf_lru *lru, u32 hash)
static void bpf_common_lru_push_free(struct bpf_lru *lru,
struct bpf_lru_node *node)
{
+ u8 node_type = READ_ONCE(node->type);
unsigned long flags;
- if (WARN_ON_ONCE(node->type == BPF_LRU_LIST_T_FREE) ||
- WARN_ON_ONCE(node->type == BPF_LRU_LOCAL_LIST_T_FREE))
+ if (WARN_ON_ONCE(node_type == BPF_LRU_LIST_T_FREE) ||
+ WARN_ON_ONCE(node_type == BPF_LRU_LOCAL_LIST_T_FREE))
return;
- if (node->type == BPF_LRU_LOCAL_LIST_T_PENDING) {
+ if (node_type == BPF_LRU_LOCAL_LIST_T_PENDING) {
struct bpf_lru_locallist *loc_l;
loc_l = per_cpu_ptr(lru->common_lru.local_list, node->cpu);
diff --git a/kernel/bpf/bpf_lsm.c b/kernel/bpf/bpf_lsm.c
index 70e5e0b6d69d..1622a44d1617 100644
--- a/kernel/bpf/bpf_lsm.c
+++ b/kernel/bpf/bpf_lsm.c
@@ -149,7 +149,11 @@ BTF_ID(func, bpf_lsm_file_ioctl)
BTF_ID(func, bpf_lsm_file_lock)
BTF_ID(func, bpf_lsm_file_open)
BTF_ID(func, bpf_lsm_file_receive)
+
+#ifdef CONFIG_SECURITY_NETWORK
BTF_ID(func, bpf_lsm_inet_conn_established)
+#endif /* CONFIG_SECURITY_NETWORK */
+
BTF_ID(func, bpf_lsm_inode_create)
BTF_ID(func, bpf_lsm_inode_free_security)
BTF_ID(func, bpf_lsm_inode_getattr)
@@ -166,7 +170,11 @@ BTF_ID(func, bpf_lsm_inode_symlink)
BTF_ID(func, bpf_lsm_inode_unlink)
BTF_ID(func, bpf_lsm_kernel_module_request)
BTF_ID(func, bpf_lsm_kernfs_init_security)
+
+#ifdef CONFIG_KEYS
BTF_ID(func, bpf_lsm_key_free)
+#endif /* CONFIG_KEYS */
+
BTF_ID(func, bpf_lsm_mmap_file)
BTF_ID(func, bpf_lsm_netlink_send)
BTF_ID(func, bpf_lsm_path_notify)
@@ -181,6 +189,8 @@ BTF_ID(func, bpf_lsm_sb_show_options)
BTF_ID(func, bpf_lsm_sb_statfs)
BTF_ID(func, bpf_lsm_sb_umount)
BTF_ID(func, bpf_lsm_settime)
+
+#ifdef CONFIG_SECURITY_NETWORK
BTF_ID(func, bpf_lsm_socket_accept)
BTF_ID(func, bpf_lsm_socket_bind)
BTF_ID(func, bpf_lsm_socket_connect)
@@ -195,6 +205,8 @@ BTF_ID(func, bpf_lsm_socket_recvmsg)
BTF_ID(func, bpf_lsm_socket_sendmsg)
BTF_ID(func, bpf_lsm_socket_shutdown)
BTF_ID(func, bpf_lsm_socket_socketpair)
+#endif /* CONFIG_SECURITY_NETWORK */
+
BTF_ID(func, bpf_lsm_syslog)
BTF_ID(func, bpf_lsm_task_alloc)
BTF_ID(func, bpf_lsm_task_getsecid)
diff --git a/kernel/bpf/btf.c b/kernel/bpf/btf.c
index 84a36ee4a4c2..2efeb5f4b343 100644
--- a/kernel/bpf/btf.c
+++ b/kernel/bpf/btf.c
@@ -458,7 +458,7 @@ static bool btf_type_is_datasec(const struct btf_type *t)
return BTF_INFO_KIND(t->info) == BTF_KIND_DATASEC;
}
-static u32 btf_nr_types_total(const struct btf *btf)
+u32 btf_nr_types(const struct btf *btf)
{
u32 total = 0;
@@ -476,7 +476,7 @@ s32 btf_find_by_name_kind(const struct btf *btf, const char *name, u8 kind)
const char *tname;
u32 i, total;
- total = btf_nr_types_total(btf);
+ total = btf_nr_types(btf);
for (i = 1; i < total; i++) {
t = btf_type_by_id(btf, i);
if (BTF_INFO_KIND(t->info) != kind)
@@ -3540,11 +3540,6 @@ static s32 btf_datasec_check_meta(struct btf_verifier_env *env,
return -EINVAL;
}
- if (!btf_type_vlen(t)) {
- btf_verifier_log_type(env, t, "vlen == 0");
- return -EINVAL;
- }
-
if (!t->size) {
btf_verifier_log_type(env, t, "size == 0");
return -EINVAL;
@@ -5296,15 +5291,16 @@ int btf_check_type_match(struct bpf_verifier_log *log, const struct bpf_prog *pr
* Only PTR_TO_CTX and SCALAR_VALUE states are recognized.
*/
int btf_check_func_arg_match(struct bpf_verifier_env *env, int subprog,
- struct bpf_reg_state *reg)
+ struct bpf_reg_state *regs)
{
struct bpf_verifier_log *log = &env->log;
struct bpf_prog *prog = env->prog;
struct btf *btf = prog->aux->btf;
const struct btf_param *args;
- const struct btf_type *t;
- u32 i, nargs, btf_id;
+ const struct btf_type *t, *ref_t;
+ u32 i, nargs, btf_id, type_size;
const char *tname;
+ bool is_global;
if (!prog->aux->func_info)
return -EINVAL;
@@ -5338,38 +5334,57 @@ int btf_check_func_arg_match(struct bpf_verifier_env *env, int subprog,
bpf_log(log, "Function %s has %d > 5 args\n", tname, nargs);
goto out;
}
+
+ is_global = prog->aux->func_info_aux[subprog].linkage == BTF_FUNC_GLOBAL;
/* check that BTF function arguments match actual types that the
* verifier sees.
*/
for (i = 0; i < nargs; i++) {
+ struct bpf_reg_state *reg = &regs[i + 1];
+
t = btf_type_by_id(btf, args[i].type);
while (btf_type_is_modifier(t))
t = btf_type_by_id(btf, t->type);
if (btf_type_is_int(t) || btf_type_is_enum(t)) {
- if (reg[i + 1].type == SCALAR_VALUE)
+ if (reg->type == SCALAR_VALUE)
continue;
bpf_log(log, "R%d is not a scalar\n", i + 1);
goto out;
}
if (btf_type_is_ptr(t)) {
- if (reg[i + 1].type == SCALAR_VALUE) {
- bpf_log(log, "R%d is not a pointer\n", i + 1);
- goto out;
- }
/* If function expects ctx type in BTF check that caller
* is passing PTR_TO_CTX.
*/
if (btf_get_prog_ctx_type(log, btf, t, prog->type, i)) {
- if (reg[i + 1].type != PTR_TO_CTX) {
+ if (reg->type != PTR_TO_CTX) {
bpf_log(log,
"arg#%d expected pointer to ctx, but got %s\n",
i, btf_kind_str[BTF_INFO_KIND(t->info)]);
goto out;
}
- if (check_ctx_reg(env, &reg[i + 1], i + 1))
+ if (check_ctx_reg(env, reg, i + 1))
goto out;
continue;
}
+
+ if (!is_global)
+ goto out;
+
+ t = btf_type_skip_modifiers(btf, t->type, NULL);
+
+ ref_t = btf_resolve_size(btf, t, &type_size);
+ if (IS_ERR(ref_t)) {
+ bpf_log(log,
+ "arg#%d reference type('%s %s') size cannot be determined: %ld\n",
+ i, btf_type_str(t), btf_name_by_offset(btf, t->name_off),
+ PTR_ERR(ref_t));
+ goto out;
+ }
+
+ if (check_mem_reg(env, reg, i + 1, type_size))
+ goto out;
+
+ continue;
}
bpf_log(log, "Unrecognized arg#%d type %s\n",
i, btf_kind_str[BTF_INFO_KIND(t->info)]);
@@ -5393,14 +5408,14 @@ out:
* (either PTR_TO_CTX or SCALAR_VALUE).
*/
int btf_prepare_func_args(struct bpf_verifier_env *env, int subprog,
- struct bpf_reg_state *reg)
+ struct bpf_reg_state *regs)
{
struct bpf_verifier_log *log = &env->log;
struct bpf_prog *prog = env->prog;
enum bpf_prog_type prog_type = prog->type;
struct btf *btf = prog->aux->btf;
const struct btf_param *args;
- const struct btf_type *t;
+ const struct btf_type *t, *ref_t;
u32 i, nargs, btf_id;
const char *tname;
@@ -5464,16 +5479,35 @@ int btf_prepare_func_args(struct bpf_verifier_env *env, int subprog,
* Only PTR_TO_CTX and SCALAR are supported atm.
*/
for (i = 0; i < nargs; i++) {
+ struct bpf_reg_state *reg = &regs[i + 1];
+
t = btf_type_by_id(btf, args[i].type);
while (btf_type_is_modifier(t))
t = btf_type_by_id(btf, t->type);
if (btf_type_is_int(t) || btf_type_is_enum(t)) {
- reg[i + 1].type = SCALAR_VALUE;
+ reg->type = SCALAR_VALUE;
continue;
}
- if (btf_type_is_ptr(t) &&
- btf_get_prog_ctx_type(log, btf, t, prog_type, i)) {
- reg[i + 1].type = PTR_TO_CTX;
+ if (btf_type_is_ptr(t)) {
+ if (btf_get_prog_ctx_type(log, btf, t, prog_type, i)) {
+ reg->type = PTR_TO_CTX;
+ continue;
+ }
+
+ t = btf_type_skip_modifiers(btf, t->type, NULL);
+
+ ref_t = btf_resolve_size(btf, t, &reg->mem_size);
+ if (IS_ERR(ref_t)) {
+ bpf_log(log,
+ "arg#%d reference type('%s %s') size cannot be determined: %ld\n",
+ i, btf_type_str(t), btf_name_by_offset(btf, t->name_off),
+ PTR_ERR(ref_t));
+ return -EINVAL;
+ }
+
+ reg->type = PTR_TO_MEM_OR_NULL;
+ reg->id = ++env->id_gen;
+
continue;
}
bpf_log(log, "Arg#%d type %s in %s() is not supported yet.\n",
@@ -5743,6 +5777,11 @@ bool btf_is_kernel(const struct btf *btf)
return btf->kernel_btf;
}
+bool btf_is_module(const struct btf *btf)
+{
+ return btf->kernel_btf && strcmp(btf->name, "vmlinux") != 0;
+}
+
static int btf_id_cmp_func(const void *a, const void *b)
{
const int *pa = a, *pb = b;
@@ -5877,3 +5916,25 @@ static int __init btf_module_init(void)
fs_initcall(btf_module_init);
#endif /* CONFIG_DEBUG_INFO_BTF_MODULES */
+
+struct module *btf_try_get_module(const struct btf *btf)
+{
+ struct module *res = NULL;
+#ifdef CONFIG_DEBUG_INFO_BTF_MODULES
+ struct btf_module *btf_mod, *tmp;
+
+ mutex_lock(&btf_module_mutex);
+ list_for_each_entry_safe(btf_mod, tmp, &btf_modules, list) {
+ if (btf_mod->btf != btf)
+ continue;
+
+ if (try_module_get(btf_mod->module))
+ res = btf_mod->module;
+
+ break;
+ }
+ mutex_unlock(&btf_module_mutex);
+#endif
+
+ return res;
+}
diff --git a/kernel/bpf/cgroup.c b/kernel/bpf/cgroup.c
index 96555a8a2c54..b567ca46555c 100644
--- a/kernel/bpf/cgroup.c
+++ b/kernel/bpf/cgroup.c
@@ -19,7 +19,7 @@
#include "../cgroup/cgroup-internal.h"
-DEFINE_STATIC_KEY_FALSE(cgroup_bpf_enabled_key);
+DEFINE_STATIC_KEY_ARRAY_FALSE(cgroup_bpf_enabled_key, MAX_BPF_ATTACH_TYPE);
EXPORT_SYMBOL(cgroup_bpf_enabled_key);
void cgroup_bpf_offline(struct cgroup *cgrp)
@@ -128,7 +128,7 @@ static void cgroup_bpf_release(struct work_struct *work)
if (pl->link)
bpf_cgroup_link_auto_detach(pl->link);
kfree(pl);
- static_branch_dec(&cgroup_bpf_enabled_key);
+ static_branch_dec(&cgroup_bpf_enabled_key[type]);
}
old_array = rcu_dereference_protected(
cgrp->bpf.effective[type],
@@ -499,7 +499,7 @@ int __cgroup_bpf_attach(struct cgroup *cgrp,
if (old_prog)
bpf_prog_put(old_prog);
else
- static_branch_inc(&cgroup_bpf_enabled_key);
+ static_branch_inc(&cgroup_bpf_enabled_key[type]);
bpf_cgroup_storages_link(new_storage, cgrp, type);
return 0;
@@ -698,7 +698,7 @@ int __cgroup_bpf_detach(struct cgroup *cgrp, struct bpf_prog *prog,
cgrp->bpf.flags[type] = 0;
if (old_prog)
bpf_prog_put(old_prog);
- static_branch_dec(&cgroup_bpf_enabled_key);
+ static_branch_dec(&cgroup_bpf_enabled_key[type]);
return 0;
cleanup:
@@ -1055,6 +1055,8 @@ EXPORT_SYMBOL(__cgroup_bpf_run_filter_sk);
* @uaddr: sockaddr struct provided by user
* @type: The type of program to be exectuted
* @t_ctx: Pointer to attach type specific context
+ * @flags: Pointer to u32 which contains higher bits of BPF program
+ * return value (OR'ed together).
*
* socket is expected to be of type INET or INET6.
*
@@ -1064,7 +1066,8 @@ EXPORT_SYMBOL(__cgroup_bpf_run_filter_sk);
int __cgroup_bpf_run_filter_sock_addr(struct sock *sk,
struct sockaddr *uaddr,
enum bpf_attach_type type,
- void *t_ctx)
+ void *t_ctx,
+ u32 *flags)
{
struct bpf_sock_addr_kern ctx = {
.sk = sk,
@@ -1087,7 +1090,8 @@ int __cgroup_bpf_run_filter_sock_addr(struct sock *sk,
}
cgrp = sock_cgroup_ptr(&sk->sk_cgrp_data);
- ret = BPF_PROG_RUN_ARRAY(cgrp->bpf.effective[type], &ctx, BPF_PROG_RUN);
+ ret = BPF_PROG_RUN_ARRAY_FLAGS(cgrp->bpf.effective[type], &ctx,
+ BPF_PROG_RUN, flags);
return ret == 1 ? 0 : -EPERM;
}
@@ -1298,7 +1302,8 @@ static bool __cgroup_bpf_prog_array_is_empty(struct cgroup *cgrp,
return empty;
}
-static int sockopt_alloc_buf(struct bpf_sockopt_kern *ctx, int max_optlen)
+static int sockopt_alloc_buf(struct bpf_sockopt_kern *ctx, int max_optlen,
+ struct bpf_sockopt_buf *buf)
{
if (unlikely(max_optlen < 0))
return -EINVAL;
@@ -1310,6 +1315,15 @@ static int sockopt_alloc_buf(struct bpf_sockopt_kern *ctx, int max_optlen)
max_optlen = PAGE_SIZE;
}
+ if (max_optlen <= sizeof(buf->data)) {
+ /* When the optval fits into BPF_SOCKOPT_KERN_BUF_SIZE
+ * bytes avoid the cost of kzalloc.
+ */
+ ctx->optval = buf->data;
+ ctx->optval_end = ctx->optval + max_optlen;
+ return max_optlen;
+ }
+
ctx->optval = kzalloc(max_optlen, GFP_USER);
if (!ctx->optval)
return -ENOMEM;
@@ -1319,16 +1333,26 @@ static int sockopt_alloc_buf(struct bpf_sockopt_kern *ctx, int max_optlen)
return max_optlen;
}
-static void sockopt_free_buf(struct bpf_sockopt_kern *ctx)
+static void sockopt_free_buf(struct bpf_sockopt_kern *ctx,
+ struct bpf_sockopt_buf *buf)
{
+ if (ctx->optval == buf->data)
+ return;
kfree(ctx->optval);
}
+static bool sockopt_buf_allocated(struct bpf_sockopt_kern *ctx,
+ struct bpf_sockopt_buf *buf)
+{
+ return ctx->optval != buf->data;
+}
+
int __cgroup_bpf_run_filter_setsockopt(struct sock *sk, int *level,
int *optname, char __user *optval,
int *optlen, char **kernel_optval)
{
struct cgroup *cgrp = sock_cgroup_ptr(&sk->sk_cgrp_data);
+ struct bpf_sockopt_buf buf = {};
struct bpf_sockopt_kern ctx = {
.sk = sk,
.level = *level,
@@ -1340,8 +1364,7 @@ int __cgroup_bpf_run_filter_setsockopt(struct sock *sk, int *level,
* attached to the hook so we don't waste time allocating
* memory and locking the socket.
*/
- if (!cgroup_bpf_enabled ||
- __cgroup_bpf_prog_array_is_empty(cgrp, BPF_CGROUP_SETSOCKOPT))
+ if (__cgroup_bpf_prog_array_is_empty(cgrp, BPF_CGROUP_SETSOCKOPT))
return 0;
/* Allocate a bit more than the initial user buffer for
@@ -1350,7 +1373,7 @@ int __cgroup_bpf_run_filter_setsockopt(struct sock *sk, int *level,
*/
max_optlen = max_t(int, 16, *optlen);
- max_optlen = sockopt_alloc_buf(&ctx, max_optlen);
+ max_optlen = sockopt_alloc_buf(&ctx, max_optlen, &buf);
if (max_optlen < 0)
return max_optlen;
@@ -1390,14 +1413,31 @@ int __cgroup_bpf_run_filter_setsockopt(struct sock *sk, int *level,
*/
if (ctx.optlen != 0) {
*optlen = ctx.optlen;
- *kernel_optval = ctx.optval;
+ /* We've used bpf_sockopt_kern->buf as an intermediary
+ * storage, but the BPF program indicates that we need
+ * to pass this data to the kernel setsockopt handler.
+ * No way to export on-stack buf, have to allocate a
+ * new buffer.
+ */
+ if (!sockopt_buf_allocated(&ctx, &buf)) {
+ void *p = kmalloc(ctx.optlen, GFP_USER);
+
+ if (!p) {
+ ret = -ENOMEM;
+ goto out;
+ }
+ memcpy(p, ctx.optval, ctx.optlen);
+ *kernel_optval = p;
+ } else {
+ *kernel_optval = ctx.optval;
+ }
/* export and don't free sockopt buf */
return 0;
}
}
out:
- sockopt_free_buf(&ctx);
+ sockopt_free_buf(&ctx, &buf);
return ret;
}
@@ -1407,6 +1447,7 @@ int __cgroup_bpf_run_filter_getsockopt(struct sock *sk, int level,
int retval)
{
struct cgroup *cgrp = sock_cgroup_ptr(&sk->sk_cgrp_data);
+ struct bpf_sockopt_buf buf = {};
struct bpf_sockopt_kern ctx = {
.sk = sk,
.level = level,
@@ -1419,13 +1460,12 @@ int __cgroup_bpf_run_filter_getsockopt(struct sock *sk, int level,
* attached to the hook so we don't waste time allocating
* memory and locking the socket.
*/
- if (!cgroup_bpf_enabled ||
- __cgroup_bpf_prog_array_is_empty(cgrp, BPF_CGROUP_GETSOCKOPT))
+ if (__cgroup_bpf_prog_array_is_empty(cgrp, BPF_CGROUP_GETSOCKOPT))
return retval;
ctx.optlen = max_optlen;
- max_optlen = sockopt_alloc_buf(&ctx, max_optlen);
+ max_optlen = sockopt_alloc_buf(&ctx, max_optlen, &buf);
if (max_optlen < 0)
return max_optlen;
@@ -1442,6 +1482,11 @@ int __cgroup_bpf_run_filter_getsockopt(struct sock *sk, int level,
goto out;
}
+ if (ctx.optlen < 0) {
+ ret = -EFAULT;
+ goto out;
+ }
+
if (copy_from_user(ctx.optval, optval,
min(ctx.optlen, max_optlen)) != 0) {
ret = -EFAULT;
@@ -1459,7 +1504,7 @@ int __cgroup_bpf_run_filter_getsockopt(struct sock *sk, int level,
goto out;
}
- if (ctx.optlen > max_optlen) {
+ if (ctx.optlen > max_optlen || ctx.optlen < 0) {
ret = -EFAULT;
goto out;
}
@@ -1483,9 +1528,55 @@ int __cgroup_bpf_run_filter_getsockopt(struct sock *sk, int level,
ret = ctx.retval;
out:
- sockopt_free_buf(&ctx);
+ sockopt_free_buf(&ctx, &buf);
return ret;
}
+
+int __cgroup_bpf_run_filter_getsockopt_kern(struct sock *sk, int level,
+ int optname, void *optval,
+ int *optlen, int retval)
+{
+ struct cgroup *cgrp = sock_cgroup_ptr(&sk->sk_cgrp_data);
+ struct bpf_sockopt_kern ctx = {
+ .sk = sk,
+ .level = level,
+ .optname = optname,
+ .retval = retval,
+ .optlen = *optlen,
+ .optval = optval,
+ .optval_end = optval + *optlen,
+ };
+ int ret;
+
+ /* Note that __cgroup_bpf_run_filter_getsockopt doesn't copy
+ * user data back into BPF buffer when reval != 0. This is
+ * done as an optimization to avoid extra copy, assuming
+ * kernel won't populate the data in case of an error.
+ * Here we always pass the data and memset() should
+ * be called if that data shouldn't be "exported".
+ */
+
+ ret = BPF_PROG_RUN_ARRAY(cgrp->bpf.effective[BPF_CGROUP_GETSOCKOPT],
+ &ctx, BPF_PROG_RUN);
+ if (!ret)
+ return -EPERM;
+
+ if (ctx.optlen > *optlen)
+ return -EFAULT;
+
+ /* BPF programs only allowed to set retval to 0, not some
+ * arbitrary value.
+ */
+ if (ctx.retval != 0 && ctx.retval != retval)
+ return -EFAULT;
+
+ /* BPF programs can shrink the buffer, export the modifications.
+ */
+ if (ctx.optlen != 0)
+ *optlen = ctx.optlen;
+
+ return ctx.retval;
+}
#endif
static ssize_t sysctl_cpy_dir(const struct ctl_dir *dir, char **bufp,
diff --git a/kernel/bpf/core.c b/kernel/bpf/core.c
index 261f8692d0d2..0ae015ad1e05 100644
--- a/kernel/bpf/core.c
+++ b/kernel/bpf/core.c
@@ -91,6 +91,12 @@ struct bpf_prog *bpf_prog_alloc_no_stats(unsigned int size, gfp_t gfp_extra_flag
vfree(fp);
return NULL;
}
+ fp->active = alloc_percpu_gfp(int, GFP_KERNEL_ACCOUNT | gfp_extra_flags);
+ if (!fp->active) {
+ vfree(fp);
+ kfree(aux);
+ return NULL;
+ }
fp->pages = size / PAGE_SIZE;
fp->aux = aux;
@@ -114,8 +120,9 @@ struct bpf_prog *bpf_prog_alloc(unsigned int size, gfp_t gfp_extra_flags)
if (!prog)
return NULL;
- prog->aux->stats = alloc_percpu_gfp(struct bpf_prog_stats, gfp_flags);
- if (!prog->aux->stats) {
+ prog->stats = alloc_percpu_gfp(struct bpf_prog_stats, gfp_flags);
+ if (!prog->stats) {
+ free_percpu(prog->active);
kfree(prog->aux);
vfree(prog);
return NULL;
@@ -124,7 +131,7 @@ struct bpf_prog *bpf_prog_alloc(unsigned int size, gfp_t gfp_extra_flags)
for_each_possible_cpu(cpu) {
struct bpf_prog_stats *pstats;
- pstats = per_cpu_ptr(prog->aux->stats, cpu);
+ pstats = per_cpu_ptr(prog->stats, cpu);
u64_stats_init(&pstats->syncp);
}
return prog;
@@ -238,6 +245,8 @@ struct bpf_prog *bpf_prog_realloc(struct bpf_prog *fp_old, unsigned int size,
* reallocated structure.
*/
fp_old->aux = NULL;
+ fp_old->stats = NULL;
+ fp_old->active = NULL;
__bpf_prog_free(fp_old);
}
@@ -249,10 +258,11 @@ void __bpf_prog_free(struct bpf_prog *fp)
if (fp->aux) {
mutex_destroy(&fp->aux->used_maps_mutex);
mutex_destroy(&fp->aux->dst_mutex);
- free_percpu(fp->aux->stats);
kfree(fp->aux->poke_tab);
kfree(fp->aux);
}
+ free_percpu(fp->stats);
+ free_percpu(fp->active);
vfree(fp);
}
@@ -1309,8 +1319,8 @@ EXPORT_SYMBOL_GPL(__bpf_call_base);
INSN_3(STX, MEM, H), \
INSN_3(STX, MEM, W), \
INSN_3(STX, MEM, DW), \
- INSN_3(STX, XADD, W), \
- INSN_3(STX, XADD, DW), \
+ INSN_3(STX, ATOMIC, W), \
+ INSN_3(STX, ATOMIC, DW), \
/* Immediate based. */ \
INSN_3(ST, MEM, B), \
INSN_3(ST, MEM, H), \
@@ -1618,13 +1628,59 @@ out:
LDX_PROBE(DW, 8)
#undef LDX_PROBE
- STX_XADD_W: /* lock xadd *(u32 *)(dst_reg + off16) += src_reg */
- atomic_add((u32) SRC, (atomic_t *)(unsigned long)
- (DST + insn->off));
- CONT;
- STX_XADD_DW: /* lock xadd *(u64 *)(dst_reg + off16) += src_reg */
- atomic64_add((u64) SRC, (atomic64_t *)(unsigned long)
- (DST + insn->off));
+#define ATOMIC_ALU_OP(BOP, KOP) \
+ case BOP: \
+ if (BPF_SIZE(insn->code) == BPF_W) \
+ atomic_##KOP((u32) SRC, (atomic_t *)(unsigned long) \
+ (DST + insn->off)); \
+ else \
+ atomic64_##KOP((u64) SRC, (atomic64_t *)(unsigned long) \
+ (DST + insn->off)); \
+ break; \
+ case BOP | BPF_FETCH: \
+ if (BPF_SIZE(insn->code) == BPF_W) \
+ SRC = (u32) atomic_fetch_##KOP( \
+ (u32) SRC, \
+ (atomic_t *)(unsigned long) (DST + insn->off)); \
+ else \
+ SRC = (u64) atomic64_fetch_##KOP( \
+ (u64) SRC, \
+ (atomic64_t *)(unsigned long) (DST + insn->off)); \
+ break;
+
+ STX_ATOMIC_DW:
+ STX_ATOMIC_W:
+ switch (IMM) {
+ ATOMIC_ALU_OP(BPF_ADD, add)
+ ATOMIC_ALU_OP(BPF_AND, and)
+ ATOMIC_ALU_OP(BPF_OR, or)
+ ATOMIC_ALU_OP(BPF_XOR, xor)
+#undef ATOMIC_ALU_OP
+
+ case BPF_XCHG:
+ if (BPF_SIZE(insn->code) == BPF_W)
+ SRC = (u32) atomic_xchg(
+ (atomic_t *)(unsigned long) (DST + insn->off),
+ (u32) SRC);
+ else
+ SRC = (u64) atomic64_xchg(
+ (atomic64_t *)(unsigned long) (DST + insn->off),
+ (u64) SRC);
+ break;
+ case BPF_CMPXCHG:
+ if (BPF_SIZE(insn->code) == BPF_W)
+ BPF_R0 = (u32) atomic_cmpxchg(
+ (atomic_t *)(unsigned long) (DST + insn->off),
+ (u32) BPF_R0, (u32) SRC);
+ else
+ BPF_R0 = (u64) atomic64_cmpxchg(
+ (atomic64_t *)(unsigned long) (DST + insn->off),
+ (u64) BPF_R0, (u64) SRC);
+ break;
+
+ default:
+ goto default_label;
+ }
CONT;
default_label:
@@ -1634,7 +1690,8 @@ out:
*
* Note, verifier whitelists all opcodes in bpf_opcode_in_insntable().
*/
- pr_warn("BPF interpreter: unknown opcode %02x\n", insn->code);
+ pr_warn("BPF interpreter: unknown opcode %02x (imm: 0x%x)\n",
+ insn->code, insn->imm);
BUG_ON(1);
return 0;
}
@@ -2119,6 +2176,28 @@ static void bpf_free_used_maps(struct bpf_prog_aux *aux)
kfree(aux->used_maps);
}
+void __bpf_free_used_btfs(struct bpf_prog_aux *aux,
+ struct btf_mod_pair *used_btfs, u32 len)
+{
+#ifdef CONFIG_BPF_SYSCALL
+ struct btf_mod_pair *btf_mod;
+ u32 i;
+
+ for (i = 0; i < len; i++) {
+ btf_mod = &used_btfs[i];
+ if (btf_mod->module)
+ module_put(btf_mod->module);
+ btf_put(btf_mod->btf);
+ }
+#endif
+}
+
+static void bpf_free_used_btfs(struct bpf_prog_aux *aux)
+{
+ __bpf_free_used_btfs(aux, aux->used_btfs, aux->used_btf_cnt);
+ kfree(aux->used_btfs);
+}
+
static void bpf_prog_free_deferred(struct work_struct *work)
{
struct bpf_prog_aux *aux;
@@ -2126,6 +2205,7 @@ static void bpf_prog_free_deferred(struct work_struct *work)
aux = container_of(work, struct bpf_prog_aux, work);
bpf_free_used_maps(aux);
+ bpf_free_used_btfs(aux);
if (bpf_prog_is_dev_bound(aux))
bpf_prog_offload_destroy(aux->prog);
#ifdef CONFIG_PERF_EVENTS
diff --git a/kernel/bpf/cpumap.c b/kernel/bpf/cpumap.c
index 747313698178..5d1469de6921 100644
--- a/kernel/bpf/cpumap.c
+++ b/kernel/bpf/cpumap.c
@@ -141,49 +141,6 @@ static void cpu_map_kthread_stop(struct work_struct *work)
kthread_stop(rcpu->kthread);
}
-static struct sk_buff *cpu_map_build_skb(struct xdp_frame *xdpf,
- struct sk_buff *skb)
-{
- unsigned int hard_start_headroom;
- unsigned int frame_size;
- void *pkt_data_start;
-
- /* Part of headroom was reserved to xdpf */
- hard_start_headroom = sizeof(struct xdp_frame) + xdpf->headroom;
-
- /* Memory size backing xdp_frame data already have reserved
- * room for build_skb to place skb_shared_info in tailroom.
- */
- frame_size = xdpf->frame_sz;
-
- pkt_data_start = xdpf->data - hard_start_headroom;
- skb = build_skb_around(skb, pkt_data_start, frame_size);
- if (unlikely(!skb))
- return NULL;
-
- skb_reserve(skb, hard_start_headroom);
- __skb_put(skb, xdpf->len);
- if (xdpf->metasize)
- skb_metadata_set(skb, xdpf->metasize);
-
- /* Essential SKB info: protocol and skb->dev */
- skb->protocol = eth_type_trans(skb, xdpf->dev_rx);
-
- /* Optional SKB info, currently missing:
- * - HW checksum info (skb->ip_summed)
- * - HW RX hash (skb_set_hash)
- * - RX ring dev queue index (skb_record_rx_queue)
- */
-
- /* Until page_pool get SKB return path, release DMA here */
- xdp_release_frame(xdpf);
-
- /* Allow SKB to reuse area used by xdp_frame */
- xdp_scrub_frame(xdpf);
-
- return skb;
-}
-
static void __cpu_map_ring_cleanup(struct ptr_ring *ring)
{
/* The tear-down procedure should have made sure that queue is
@@ -350,7 +307,8 @@ static int cpu_map_kthread_run(void *data)
struct sk_buff *skb = skbs[i];
int ret;
- skb = cpu_map_build_skb(xdpf, skb);
+ skb = __xdp_build_skb_from_frame(xdpf, skb,
+ xdpf->dev_rx);
if (!skb) {
xdp_return_frame(xdpf);
continue;
diff --git a/kernel/bpf/devmap.c b/kernel/bpf/devmap.c
index f6e9c68afdd4..85d9d1b72a33 100644
--- a/kernel/bpf/devmap.c
+++ b/kernel/bpf/devmap.c
@@ -802,9 +802,7 @@ static int dev_map_notification(struct notifier_block *notifier,
break;
/* will be freed in free_netdev() */
- netdev->xdp_bulkq =
- __alloc_percpu_gfp(sizeof(struct xdp_dev_bulk_queue),
- sizeof(void *), GFP_ATOMIC);
+ netdev->xdp_bulkq = alloc_percpu(struct xdp_dev_bulk_queue);
if (!netdev->xdp_bulkq)
return NOTIFY_BAD;
diff --git a/kernel/bpf/disasm.c b/kernel/bpf/disasm.c
index b44d8c447afd..3acc7e0b6916 100644
--- a/kernel/bpf/disasm.c
+++ b/kernel/bpf/disasm.c
@@ -80,6 +80,13 @@ const char *const bpf_alu_string[16] = {
[BPF_END >> 4] = "endian",
};
+static const char *const bpf_atomic_alu_string[16] = {
+ [BPF_ADD >> 4] = "add",
+ [BPF_AND >> 4] = "and",
+ [BPF_OR >> 4] = "or",
+ [BPF_XOR >> 4] = "or",
+};
+
static const char *const bpf_ldst_string[] = {
[BPF_W >> 3] = "u32",
[BPF_H >> 3] = "u16",
@@ -153,14 +160,44 @@ void print_bpf_insn(const struct bpf_insn_cbs *cbs,
bpf_ldst_string[BPF_SIZE(insn->code) >> 3],
insn->dst_reg,
insn->off, insn->src_reg);
- else if (BPF_MODE(insn->code) == BPF_XADD)
- verbose(cbs->private_data, "(%02x) lock *(%s *)(r%d %+d) += r%d\n",
+ else if (BPF_MODE(insn->code) == BPF_ATOMIC &&
+ (insn->imm == BPF_ADD || insn->imm == BPF_AND ||
+ insn->imm == BPF_OR || insn->imm == BPF_XOR)) {
+ verbose(cbs->private_data, "(%02x) lock *(%s *)(r%d %+d) %s r%d\n",
+ insn->code,
+ bpf_ldst_string[BPF_SIZE(insn->code) >> 3],
+ insn->dst_reg, insn->off,
+ bpf_alu_string[BPF_OP(insn->imm) >> 4],
+ insn->src_reg);
+ } else if (BPF_MODE(insn->code) == BPF_ATOMIC &&
+ (insn->imm == (BPF_ADD | BPF_FETCH) ||
+ insn->imm == (BPF_AND | BPF_FETCH) ||
+ insn->imm == (BPF_OR | BPF_FETCH) ||
+ insn->imm == (BPF_XOR | BPF_FETCH))) {
+ verbose(cbs->private_data, "(%02x) r%d = atomic%s_fetch_%s((%s *)(r%d %+d), r%d)\n",
+ insn->code, insn->src_reg,
+ BPF_SIZE(insn->code) == BPF_DW ? "64" : "",
+ bpf_atomic_alu_string[BPF_OP(insn->imm) >> 4],
+ bpf_ldst_string[BPF_SIZE(insn->code) >> 3],
+ insn->dst_reg, insn->off, insn->src_reg);
+ } else if (BPF_MODE(insn->code) == BPF_ATOMIC &&
+ insn->imm == BPF_CMPXCHG) {
+ verbose(cbs->private_data, "(%02x) r0 = atomic%s_cmpxchg((%s *)(r%d %+d), r0, r%d)\n",
insn->code,
+ BPF_SIZE(insn->code) == BPF_DW ? "64" : "",
bpf_ldst_string[BPF_SIZE(insn->code) >> 3],
insn->dst_reg, insn->off,
insn->src_reg);
- else
+ } else if (BPF_MODE(insn->code) == BPF_ATOMIC &&
+ insn->imm == BPF_XCHG) {
+ verbose(cbs->private_data, "(%02x) r%d = atomic%s_xchg((%s *)(r%d %+d), r%d)\n",
+ insn->code, insn->src_reg,
+ BPF_SIZE(insn->code) == BPF_DW ? "64" : "",
+ bpf_ldst_string[BPF_SIZE(insn->code) >> 3],
+ insn->dst_reg, insn->off, insn->src_reg);
+ } else {
verbose(cbs->private_data, "BUG_%02x\n", insn->code);
+ }
} else if (class == BPF_ST) {
if (BPF_MODE(insn->code) != BPF_MEM) {
verbose(cbs->private_data, "BUG_st_%02x\n", insn->code);
diff --git a/kernel/bpf/hashtab.c b/kernel/bpf/hashtab.c
index c1ac7f964bc9..d63912e73ad9 100644
--- a/kernel/bpf/hashtab.c
+++ b/kernel/bpf/hashtab.c
@@ -1148,7 +1148,7 @@ static int __htab_percpu_map_update_elem(struct bpf_map *map, void *key,
/* unknown flags */
return -EINVAL;
- WARN_ON_ONCE(!rcu_read_lock_held());
+ WARN_ON_ONCE(!rcu_read_lock_held() && !rcu_read_lock_trace_held());
key_size = map->key_size;
@@ -1202,7 +1202,7 @@ static int __htab_lru_percpu_map_update_elem(struct bpf_map *map, void *key,
/* unknown flags */
return -EINVAL;
- WARN_ON_ONCE(!rcu_read_lock_held());
+ WARN_ON_ONCE(!rcu_read_lock_held() && !rcu_read_lock_trace_held());
key_size = map->key_size;
diff --git a/kernel/bpf/helpers.c b/kernel/bpf/helpers.c
index 41ca280b1dc1..308427fe03a3 100644
--- a/kernel/bpf/helpers.c
+++ b/kernel/bpf/helpers.c
@@ -720,14 +720,6 @@ bpf_base_func_proto(enum bpf_func_id func_id)
return &bpf_spin_lock_proto;
case BPF_FUNC_spin_unlock:
return &bpf_spin_unlock_proto;
- case BPF_FUNC_trace_printk:
- if (!perfmon_capable())
- return NULL;
- return bpf_get_trace_printk_proto();
- case BPF_FUNC_snprintf_btf:
- if (!perfmon_capable())
- return NULL;
- return &bpf_snprintf_btf_proto;
case BPF_FUNC_jiffies64:
return &bpf_jiffies64_proto;
case BPF_FUNC_per_cpu_ptr:
@@ -742,6 +734,8 @@ bpf_base_func_proto(enum bpf_func_id func_id)
return NULL;
switch (func_id) {
+ case BPF_FUNC_trace_printk:
+ return bpf_get_trace_printk_proto();
case BPF_FUNC_get_current_task:
return &bpf_get_current_task_proto;
case BPF_FUNC_probe_read_user:
@@ -752,6 +746,8 @@ bpf_base_func_proto(enum bpf_func_id func_id)
return &bpf_probe_read_user_str_proto;
case BPF_FUNC_probe_read_kernel_str:
return &bpf_probe_read_kernel_str_proto;
+ case BPF_FUNC_snprintf_btf:
+ return &bpf_snprintf_btf_proto;
default:
return NULL;
}
diff --git a/kernel/bpf/inode.c b/kernel/bpf/inode.c
index dd4b7fd60ee7..1576ff331ee4 100644
--- a/kernel/bpf/inode.c
+++ b/kernel/bpf/inode.c
@@ -122,7 +122,7 @@ static struct inode *bpf_get_inode(struct super_block *sb,
inode->i_mtime = inode->i_atime;
inode->i_ctime = inode->i_atime;
- inode_init_owner(inode, dir, mode);
+ inode_init_owner(&init_user_ns, inode, dir, mode);
return inode;
}
@@ -152,7 +152,8 @@ static void bpf_dentry_finalize(struct dentry *dentry, struct inode *inode,
dir->i_ctime = dir->i_mtime;
}
-static int bpf_mkdir(struct inode *dir, struct dentry *dentry, umode_t mode)
+static int bpf_mkdir(struct user_namespace *mnt_userns, struct inode *dir,
+ struct dentry *dentry, umode_t mode)
{
struct inode *inode;
@@ -381,8 +382,8 @@ bpf_lookup(struct inode *dir, struct dentry *dentry, unsigned flags)
return simple_lookup(dir, dentry, flags);
}
-static int bpf_symlink(struct inode *dir, struct dentry *dentry,
- const char *target)
+static int bpf_symlink(struct user_namespace *mnt_userns, struct inode *dir,
+ struct dentry *dentry, const char *target)
{
char *link = kstrdup(target, GFP_USER | __GFP_NOWARN);
struct inode *inode;
@@ -507,7 +508,7 @@ static void *bpf_obj_do_get(const char __user *pathname,
return ERR_PTR(ret);
inode = d_backing_inode(path.dentry);
- ret = inode_permission(inode, ACC_MODE(flags));
+ ret = path_permission(&path, ACC_MODE(flags));
if (ret)
goto out;
@@ -558,7 +559,7 @@ int bpf_obj_get_user(const char __user *pathname, int flags)
static struct bpf_prog *__get_prog_inode(struct inode *inode, enum bpf_prog_type type)
{
struct bpf_prog *prog;
- int ret = inode_permission(inode, MAY_READ);
+ int ret = inode_permission(&init_user_ns, inode, MAY_READ);
if (ret)
return ERR_PTR(ret);
diff --git a/kernel/bpf/preload/Makefile b/kernel/bpf/preload/Makefile
index 23ee310b6eb4..1951332dd15f 100644
--- a/kernel/bpf/preload/Makefile
+++ b/kernel/bpf/preload/Makefile
@@ -4,8 +4,11 @@ LIBBPF_SRCS = $(srctree)/tools/lib/bpf/
LIBBPF_A = $(obj)/libbpf.a
LIBBPF_OUT = $(abspath $(obj))
+# Although not in use by libbpf's Makefile, set $(O) so that the "dummy" test
+# in tools/scripts/Makefile.include always succeeds when building the kernel
+# with $(O) pointing to a relative path, as in "make O=build bindeb-pkg".
$(LIBBPF_A):
- $(Q)$(MAKE) -C $(LIBBPF_SRCS) OUTPUT=$(LIBBPF_OUT)/ $(LIBBPF_OUT)/libbpf.a
+ $(Q)$(MAKE) -C $(LIBBPF_SRCS) O=$(LIBBPF_OUT)/ OUTPUT=$(LIBBPF_OUT)/ $(LIBBPF_OUT)/libbpf.a
userccflags += -I $(srctree)/tools/include/ -I $(srctree)/tools/include/uapi \
-I $(srctree)/tools/lib/ -Wno-unused-result
diff --git a/kernel/bpf/preload/iterators/iterators.c b/kernel/bpf/preload/iterators/iterators.c
index b7ff87939172..5d872a705470 100644
--- a/kernel/bpf/preload/iterators/iterators.c
+++ b/kernel/bpf/preload/iterators/iterators.c
@@ -1,6 +1,6 @@
// SPDX-License-Identifier: GPL-2.0
/* Copyright (c) 2020 Facebook */
-#include <argp.h>
+#include <errno.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
diff --git a/kernel/bpf/stackmap.c b/kernel/bpf/stackmap.c
index aea96b638473..be35bfb7fb13 100644
--- a/kernel/bpf/stackmap.c
+++ b/kernel/bpf/stackmap.c
@@ -7,10 +7,9 @@
#include <linux/kernel.h>
#include <linux/stacktrace.h>
#include <linux/perf_event.h>
-#include <linux/elf.h>
-#include <linux/pagemap.h>
#include <linux/irq_work.h>
#include <linux/btf_ids.h>
+#include <linux/buildid.h>
#include "percpu_freelist.h"
#define STACK_CREATE_FLAG_MASK \
@@ -115,6 +114,8 @@ static struct bpf_map *stack_map_alloc(union bpf_attr *attr)
/* hash table size must be power of 2 */
n_buckets = roundup_pow_of_two(attr->max_entries);
+ if (!n_buckets)
+ return ERR_PTR(-E2BIG);
cost = n_buckets * sizeof(struct stack_map_bucket *) + sizeof(*smap);
cost += n_buckets * (value_size + sizeof(struct stack_map_bucket));
@@ -143,140 +144,6 @@ free_smap:
return ERR_PTR(err);
}
-#define BPF_BUILD_ID 3
-/*
- * Parse build id from the note segment. This logic can be shared between
- * 32-bit and 64-bit system, because Elf32_Nhdr and Elf64_Nhdr are
- * identical.
- */
-static inline int stack_map_parse_build_id(void *page_addr,
- unsigned char *build_id,
- void *note_start,
- Elf32_Word note_size)
-{
- Elf32_Word note_offs = 0, new_offs;
-
- /* check for overflow */
- if (note_start < page_addr || note_start + note_size < note_start)
- return -EINVAL;
-
- /* only supports note that fits in the first page */
- if (note_start + note_size > page_addr + PAGE_SIZE)
- return -EINVAL;
-
- while (note_offs + sizeof(Elf32_Nhdr) < note_size) {
- Elf32_Nhdr *nhdr = (Elf32_Nhdr *)(note_start + note_offs);
-
- if (nhdr->n_type == BPF_BUILD_ID &&
- nhdr->n_namesz == sizeof("GNU") &&
- nhdr->n_descsz > 0 &&
- nhdr->n_descsz <= BPF_BUILD_ID_SIZE) {
- memcpy(build_id,
- note_start + note_offs +
- ALIGN(sizeof("GNU"), 4) + sizeof(Elf32_Nhdr),
- nhdr->n_descsz);
- memset(build_id + nhdr->n_descsz, 0,
- BPF_BUILD_ID_SIZE - nhdr->n_descsz);
- return 0;
- }
- new_offs = note_offs + sizeof(Elf32_Nhdr) +
- ALIGN(nhdr->n_namesz, 4) + ALIGN(nhdr->n_descsz, 4);
- if (new_offs <= note_offs) /* overflow */
- break;
- note_offs = new_offs;
- }
- return -EINVAL;
-}
-
-/* Parse build ID from 32-bit ELF */
-static int stack_map_get_build_id_32(void *page_addr,
- unsigned char *build_id)
-{
- Elf32_Ehdr *ehdr = (Elf32_Ehdr *)page_addr;
- Elf32_Phdr *phdr;
- int i;
-
- /* only supports phdr that fits in one page */
- if (ehdr->e_phnum >
- (PAGE_SIZE - sizeof(Elf32_Ehdr)) / sizeof(Elf32_Phdr))
- return -EINVAL;
-
- phdr = (Elf32_Phdr *)(page_addr + sizeof(Elf32_Ehdr));
-
- for (i = 0; i < ehdr->e_phnum; ++i) {
- if (phdr[i].p_type == PT_NOTE &&
- !stack_map_parse_build_id(page_addr, build_id,
- page_addr + phdr[i].p_offset,
- phdr[i].p_filesz))
- return 0;
- }
- return -EINVAL;
-}
-
-/* Parse build ID from 64-bit ELF */
-static int stack_map_get_build_id_64(void *page_addr,
- unsigned char *build_id)
-{
- Elf64_Ehdr *ehdr = (Elf64_Ehdr *)page_addr;
- Elf64_Phdr *phdr;
- int i;
-
- /* only supports phdr that fits in one page */
- if (ehdr->e_phnum >
- (PAGE_SIZE - sizeof(Elf64_Ehdr)) / sizeof(Elf64_Phdr))
- return -EINVAL;
-
- phdr = (Elf64_Phdr *)(page_addr + sizeof(Elf64_Ehdr));
-
- for (i = 0; i < ehdr->e_phnum; ++i) {
- if (phdr[i].p_type == PT_NOTE &&
- !stack_map_parse_build_id(page_addr, build_id,
- page_addr + phdr[i].p_offset,
- phdr[i].p_filesz))
- return 0;
- }
- return -EINVAL;
-}
-
-/* Parse build ID of ELF file mapped to vma */
-static int stack_map_get_build_id(struct vm_area_struct *vma,
- unsigned char *build_id)
-{
- Elf32_Ehdr *ehdr;
- struct page *page;
- void *page_addr;
- int ret;
-
- /* only works for page backed storage */
- if (!vma->vm_file)
- return -EINVAL;
-
- page = find_get_page(vma->vm_file->f_mapping, 0);
- if (!page)
- return -EFAULT; /* page not mapped */
-
- ret = -EINVAL;
- page_addr = kmap_atomic(page);
- ehdr = (Elf32_Ehdr *)page_addr;
-
- /* compare magic x7f "ELF" */
- if (memcmp(ehdr->e_ident, ELFMAG, SELFMAG) != 0)
- goto out;
-
- /* only support executable file and shared object file */
- if (ehdr->e_type != ET_EXEC && ehdr->e_type != ET_DYN)
- goto out;
-
- if (ehdr->e_ident[EI_CLASS] == ELFCLASS32)
- ret = stack_map_get_build_id_32(page_addr, build_id);
- else if (ehdr->e_ident[EI_CLASS] == ELFCLASS64)
- ret = stack_map_get_build_id_64(page_addr, build_id);
-out:
- kunmap_atomic(page_addr);
- put_page(page);
- return ret;
-}
-
static void stack_map_get_build_id_offset(struct bpf_stack_build_id *id_offs,
u64 *ips, u32 trace_nr, bool user)
{
@@ -317,18 +184,18 @@ static void stack_map_get_build_id_offset(struct bpf_stack_build_id *id_offs,
for (i = 0; i < trace_nr; i++) {
id_offs[i].status = BPF_STACK_BUILD_ID_IP;
id_offs[i].ip = ips[i];
- memset(id_offs[i].build_id, 0, BPF_BUILD_ID_SIZE);
+ memset(id_offs[i].build_id, 0, BUILD_ID_SIZE_MAX);
}
return;
}
for (i = 0; i < trace_nr; i++) {
vma = find_vma(current->mm, ips[i]);
- if (!vma || stack_map_get_build_id(vma, id_offs[i].build_id)) {
+ if (!vma || build_id_parse(vma, id_offs[i].build_id, NULL)) {
/* per entry fall back to ips */
id_offs[i].status = BPF_STACK_BUILD_ID_IP;
id_offs[i].ip = ips[i];
- memset(id_offs[i].build_id, 0, BPF_BUILD_ID_SIZE);
+ memset(id_offs[i].build_id, 0, BUILD_ID_SIZE_MAX);
continue;
}
id_offs[i].offset = (vma->vm_pgoff << PAGE_SHIFT) + ips[i]
diff --git a/kernel/bpf/syscall.c b/kernel/bpf/syscall.c
index e5999d86c76e..c859bc46d06c 100644
--- a/kernel/bpf/syscall.c
+++ b/kernel/bpf/syscall.c
@@ -1731,25 +1731,28 @@ static int bpf_prog_release(struct inode *inode, struct file *filp)
static void bpf_prog_get_stats(const struct bpf_prog *prog,
struct bpf_prog_stats *stats)
{
- u64 nsecs = 0, cnt = 0;
+ u64 nsecs = 0, cnt = 0, misses = 0;
int cpu;
for_each_possible_cpu(cpu) {
const struct bpf_prog_stats *st;
unsigned int start;
- u64 tnsecs, tcnt;
+ u64 tnsecs, tcnt, tmisses;
- st = per_cpu_ptr(prog->aux->stats, cpu);
+ st = per_cpu_ptr(prog->stats, cpu);
do {
start = u64_stats_fetch_begin_irq(&st->syncp);
tnsecs = st->nsecs;
tcnt = st->cnt;
+ tmisses = st->misses;
} while (u64_stats_fetch_retry_irq(&st->syncp, start));
nsecs += tnsecs;
cnt += tcnt;
+ misses += tmisses;
}
stats->nsecs = nsecs;
stats->cnt = cnt;
+ stats->misses = misses;
}
#ifdef CONFIG_PROC_FS
@@ -1768,14 +1771,16 @@ static void bpf_prog_show_fdinfo(struct seq_file *m, struct file *filp)
"memlock:\t%llu\n"
"prog_id:\t%u\n"
"run_time_ns:\t%llu\n"
- "run_cnt:\t%llu\n",
+ "run_cnt:\t%llu\n"
+ "recursion_misses:\t%llu\n",
prog->type,
prog->jited,
prog_tag,
prog->pages * 1ULL << PAGE_SHIFT,
prog->aux->id,
stats.nsecs,
- stats.cnt);
+ stats.cnt,
+ stats.misses);
}
#endif
@@ -3438,6 +3443,7 @@ static int bpf_prog_get_info_by_fd(struct file *file,
bpf_prog_get_stats(prog, &stats);
info.run_time_ns = stats.nsecs;
info.run_cnt = stats.cnt;
+ info.recursion_misses = stats.misses;
if (!bpf_capable()) {
info.jited_prog_len = 0;
diff --git a/kernel/bpf/task_iter.c b/kernel/bpf/task_iter.c
index 175b7b42bfc4..b68cb5d6d6eb 100644
--- a/kernel/bpf/task_iter.c
+++ b/kernel/bpf/task_iter.c
@@ -286,9 +286,248 @@ static const struct seq_operations task_file_seq_ops = {
.show = task_file_seq_show,
};
+struct bpf_iter_seq_task_vma_info {
+ /* The first field must be struct bpf_iter_seq_task_common.
+ * this is assumed by {init, fini}_seq_pidns() callback functions.
+ */
+ struct bpf_iter_seq_task_common common;
+ struct task_struct *task;
+ struct vm_area_struct *vma;
+ u32 tid;
+ unsigned long prev_vm_start;
+ unsigned long prev_vm_end;
+};
+
+enum bpf_task_vma_iter_find_op {
+ task_vma_iter_first_vma, /* use mm->mmap */
+ task_vma_iter_next_vma, /* use curr_vma->vm_next */
+ task_vma_iter_find_vma, /* use find_vma() to find next vma */
+};
+
+static struct vm_area_struct *
+task_vma_seq_get_next(struct bpf_iter_seq_task_vma_info *info)
+{
+ struct pid_namespace *ns = info->common.ns;
+ enum bpf_task_vma_iter_find_op op;
+ struct vm_area_struct *curr_vma;
+ struct task_struct *curr_task;
+ u32 curr_tid = info->tid;
+
+ /* If this function returns a non-NULL vma, it holds a reference to
+ * the task_struct, and holds read lock on vma->mm->mmap_lock.
+ * If this function returns NULL, it does not hold any reference or
+ * lock.
+ */
+ if (info->task) {
+ curr_task = info->task;
+ curr_vma = info->vma;
+ /* In case of lock contention, drop mmap_lock to unblock
+ * the writer.
+ *
+ * After relock, call find(mm, prev_vm_end - 1) to find
+ * new vma to process.
+ *
+ * +------+------+-----------+
+ * | VMA1 | VMA2 | VMA3 |
+ * +------+------+-----------+
+ * | | | |
+ * 4k 8k 16k 400k
+ *
+ * For example, curr_vma == VMA2. Before unlock, we set
+ *
+ * prev_vm_start = 8k
+ * prev_vm_end = 16k
+ *
+ * There are a few cases:
+ *
+ * 1) VMA2 is freed, but VMA3 exists.
+ *
+ * find_vma() will return VMA3, just process VMA3.
+ *
+ * 2) VMA2 still exists.
+ *
+ * find_vma() will return VMA2, process VMA2->next.
+ *
+ * 3) no more vma in this mm.
+ *
+ * Process the next task.
+ *
+ * 4) find_vma() returns a different vma, VMA2'.
+ *
+ * 4.1) If VMA2 covers same range as VMA2', skip VMA2',
+ * because we already covered the range;
+ * 4.2) VMA2 and VMA2' covers different ranges, process
+ * VMA2'.
+ */
+ if (mmap_lock_is_contended(curr_task->mm)) {
+ info->prev_vm_start = curr_vma->vm_start;
+ info->prev_vm_end = curr_vma->vm_end;
+ op = task_vma_iter_find_vma;
+ mmap_read_unlock(curr_task->mm);
+ if (mmap_read_lock_killable(curr_task->mm))
+ goto finish;
+ } else {
+ op = task_vma_iter_next_vma;
+ }
+ } else {
+again:
+ curr_task = task_seq_get_next(ns, &curr_tid, true);
+ if (!curr_task) {
+ info->tid = curr_tid + 1;
+ goto finish;
+ }
+
+ if (curr_tid != info->tid) {
+ info->tid = curr_tid;
+ /* new task, process the first vma */
+ op = task_vma_iter_first_vma;
+ } else {
+ /* Found the same tid, which means the user space
+ * finished data in previous buffer and read more.
+ * We dropped mmap_lock before returning to user
+ * space, so it is necessary to use find_vma() to
+ * find the next vma to process.
+ */
+ op = task_vma_iter_find_vma;
+ }
+
+ if (!curr_task->mm)
+ goto next_task;
+
+ if (mmap_read_lock_killable(curr_task->mm))
+ goto finish;
+ }
+
+ switch (op) {
+ case task_vma_iter_first_vma:
+ curr_vma = curr_task->mm->mmap;
+ break;
+ case task_vma_iter_next_vma:
+ curr_vma = curr_vma->vm_next;
+ break;
+ case task_vma_iter_find_vma:
+ /* We dropped mmap_lock so it is necessary to use find_vma
+ * to find the next vma. This is similar to the mechanism
+ * in show_smaps_rollup().
+ */
+ curr_vma = find_vma(curr_task->mm, info->prev_vm_end - 1);
+ /* case 1) and 4.2) above just use curr_vma */
+
+ /* check for case 2) or case 4.1) above */
+ if (curr_vma &&
+ curr_vma->vm_start == info->prev_vm_start &&
+ curr_vma->vm_end == info->prev_vm_end)
+ curr_vma = curr_vma->vm_next;
+ break;
+ }
+ if (!curr_vma) {
+ /* case 3) above, or case 2) 4.1) with vma->next == NULL */
+ mmap_read_unlock(curr_task->mm);
+ goto next_task;
+ }
+ info->task = curr_task;
+ info->vma = curr_vma;
+ return curr_vma;
+
+next_task:
+ put_task_struct(curr_task);
+ info->task = NULL;
+ curr_tid++;
+ goto again;
+
+finish:
+ if (curr_task)
+ put_task_struct(curr_task);
+ info->task = NULL;
+ info->vma = NULL;
+ return NULL;
+}
+
+static void *task_vma_seq_start(struct seq_file *seq, loff_t *pos)
+{
+ struct bpf_iter_seq_task_vma_info *info = seq->private;
+ struct vm_area_struct *vma;
+
+ vma = task_vma_seq_get_next(info);
+ if (vma && *pos == 0)
+ ++*pos;
+
+ return vma;
+}
+
+static void *task_vma_seq_next(struct seq_file *seq, void *v, loff_t *pos)
+{
+ struct bpf_iter_seq_task_vma_info *info = seq->private;
+
+ ++*pos;
+ return task_vma_seq_get_next(info);
+}
+
+struct bpf_iter__task_vma {
+ __bpf_md_ptr(struct bpf_iter_meta *, meta);
+ __bpf_md_ptr(struct task_struct *, task);
+ __bpf_md_ptr(struct vm_area_struct *, vma);
+};
+
+DEFINE_BPF_ITER_FUNC(task_vma, struct bpf_iter_meta *meta,
+ struct task_struct *task, struct vm_area_struct *vma)
+
+static int __task_vma_seq_show(struct seq_file *seq, bool in_stop)
+{
+ struct bpf_iter_seq_task_vma_info *info = seq->private;
+ struct bpf_iter__task_vma ctx;
+ struct bpf_iter_meta meta;
+ struct bpf_prog *prog;
+
+ meta.seq = seq;
+ prog = bpf_iter_get_info(&meta, in_stop);
+ if (!prog)
+ return 0;
+
+ ctx.meta = &meta;
+ ctx.task = info->task;
+ ctx.vma = info->vma;
+ return bpf_iter_run_prog(prog, &ctx);
+}
+
+static int task_vma_seq_show(struct seq_file *seq, void *v)
+{
+ return __task_vma_seq_show(seq, false);
+}
+
+static void task_vma_seq_stop(struct seq_file *seq, void *v)
+{
+ struct bpf_iter_seq_task_vma_info *info = seq->private;
+
+ if (!v) {
+ (void)__task_vma_seq_show(seq, true);
+ } else {
+ /* info->vma has not been seen by the BPF program. If the
+ * user space reads more, task_vma_seq_get_next should
+ * return this vma again. Set prev_vm_start to ~0UL,
+ * so that we don't skip the vma returned by the next
+ * find_vma() (case task_vma_iter_find_vma in
+ * task_vma_seq_get_next()).
+ */
+ info->prev_vm_start = ~0UL;
+ info->prev_vm_end = info->vma->vm_end;
+ mmap_read_unlock(info->task->mm);
+ put_task_struct(info->task);
+ info->task = NULL;
+ }
+}
+
+static const struct seq_operations task_vma_seq_ops = {
+ .start = task_vma_seq_start,
+ .next = task_vma_seq_next,
+ .stop = task_vma_seq_stop,
+ .show = task_vma_seq_show,
+};
+
BTF_ID_LIST(btf_task_file_ids)
BTF_ID(struct, task_struct)
BTF_ID(struct, file)
+BTF_ID(struct, vm_area_struct)
static const struct bpf_iter_seq_info task_seq_info = {
.seq_ops = &task_seq_ops,
@@ -328,6 +567,26 @@ static struct bpf_iter_reg task_file_reg_info = {
.seq_info = &task_file_seq_info,
};
+static const struct bpf_iter_seq_info task_vma_seq_info = {
+ .seq_ops = &task_vma_seq_ops,
+ .init_seq_private = init_seq_pidns,
+ .fini_seq_private = fini_seq_pidns,
+ .seq_priv_size = sizeof(struct bpf_iter_seq_task_vma_info),
+};
+
+static struct bpf_iter_reg task_vma_reg_info = {
+ .target = "task_vma",
+ .feature = BPF_ITER_RESCHED,
+ .ctx_arg_info_size = 2,
+ .ctx_arg_info = {
+ { offsetof(struct bpf_iter__task_vma, task),
+ PTR_TO_BTF_ID_OR_NULL },
+ { offsetof(struct bpf_iter__task_vma, vma),
+ PTR_TO_BTF_ID_OR_NULL },
+ },
+ .seq_info = &task_vma_seq_info,
+};
+
static int __init task_iter_init(void)
{
int ret;
@@ -339,6 +598,12 @@ static int __init task_iter_init(void)
task_file_reg_info.ctx_arg_info[0].btf_id = btf_task_file_ids[0];
task_file_reg_info.ctx_arg_info[1].btf_id = btf_task_file_ids[1];
- return bpf_iter_reg_target(&task_file_reg_info);
+ ret = bpf_iter_reg_target(&task_file_reg_info);
+ if (ret)
+ return ret;
+
+ task_vma_reg_info.ctx_arg_info[0].btf_id = btf_task_file_ids[0];
+ task_vma_reg_info.ctx_arg_info[1].btf_id = btf_task_file_ids[2];
+ return bpf_iter_reg_target(&task_vma_reg_info);
}
late_initcall(task_iter_init);
diff --git a/kernel/bpf/trampoline.c b/kernel/bpf/trampoline.c
index 35c5887d82ff..7bc3b3209224 100644
--- a/kernel/bpf/trampoline.c
+++ b/kernel/bpf/trampoline.c
@@ -381,55 +381,100 @@ out:
mutex_unlock(&trampoline_mutex);
}
+#define NO_START_TIME 1
+static u64 notrace bpf_prog_start_time(void)
+{
+ u64 start = NO_START_TIME;
+
+ if (static_branch_unlikely(&bpf_stats_enabled_key)) {
+ start = sched_clock();
+ if (unlikely(!start))
+ start = NO_START_TIME;
+ }
+ return start;
+}
+
+static void notrace inc_misses_counter(struct bpf_prog *prog)
+{
+ struct bpf_prog_stats *stats;
+
+ stats = this_cpu_ptr(prog->stats);
+ u64_stats_update_begin(&stats->syncp);
+ stats->misses++;
+ u64_stats_update_end(&stats->syncp);
+}
+
/* The logic is similar to BPF_PROG_RUN, but with an explicit
* rcu_read_lock() and migrate_disable() which are required
* for the trampoline. The macro is split into
- * call _bpf_prog_enter
+ * call __bpf_prog_enter
* call prog->bpf_func
* call __bpf_prog_exit
+ *
+ * __bpf_prog_enter returns:
+ * 0 - skip execution of the bpf prog
+ * 1 - execute bpf prog
+ * [2..MAX_U64] - excute bpf prog and record execution time.
+ * This is start time.
*/
-u64 notrace __bpf_prog_enter(void)
+u64 notrace __bpf_prog_enter(struct bpf_prog *prog)
__acquires(RCU)
{
- u64 start = 0;
-
rcu_read_lock();
migrate_disable();
- if (static_branch_unlikely(&bpf_stats_enabled_key))
- start = sched_clock();
- return start;
+ if (unlikely(__this_cpu_inc_return(*(prog->active)) != 1)) {
+ inc_misses_counter(prog);
+ return 0;
+ }
+ return bpf_prog_start_time();
}
-void notrace __bpf_prog_exit(struct bpf_prog *prog, u64 start)
- __releases(RCU)
+static void notrace update_prog_stats(struct bpf_prog *prog,
+ u64 start)
{
struct bpf_prog_stats *stats;
if (static_branch_unlikely(&bpf_stats_enabled_key) &&
- /* static_key could be enabled in __bpf_prog_enter
- * and disabled in __bpf_prog_exit.
+ /* static_key could be enabled in __bpf_prog_enter*
+ * and disabled in __bpf_prog_exit*.
* And vice versa.
- * Hence check that 'start' is not zero.
+ * Hence check that 'start' is valid.
*/
- start) {
- stats = this_cpu_ptr(prog->aux->stats);
+ start > NO_START_TIME) {
+ stats = this_cpu_ptr(prog->stats);
u64_stats_update_begin(&stats->syncp);
stats->cnt++;
stats->nsecs += sched_clock() - start;
u64_stats_update_end(&stats->syncp);
}
+}
+
+void notrace __bpf_prog_exit(struct bpf_prog *prog, u64 start)
+ __releases(RCU)
+{
+ update_prog_stats(prog, start);
+ __this_cpu_dec(*(prog->active));
migrate_enable();
rcu_read_unlock();
}
-void notrace __bpf_prog_enter_sleepable(void)
+u64 notrace __bpf_prog_enter_sleepable(struct bpf_prog *prog)
{
rcu_read_lock_trace();
+ migrate_disable();
might_fault();
+ if (unlikely(__this_cpu_inc_return(*(prog->active)) != 1)) {
+ inc_misses_counter(prog);
+ return 0;
+ }
+ return bpf_prog_start_time();
}
-void notrace __bpf_prog_exit_sleepable(void)
+void notrace __bpf_prog_exit_sleepable(struct bpf_prog *prog, u64 start)
{
+ update_prog_stats(prog, start);
+ __this_cpu_dec(*(prog->active));
+ migrate_enable();
rcu_read_unlock_trace();
}
diff --git a/kernel/bpf/verifier.c b/kernel/bpf/verifier.c
index e7368c5eacb7..1dda9d81f12c 100644
--- a/kernel/bpf/verifier.c
+++ b/kernel/bpf/verifier.c
@@ -228,6 +228,12 @@ static void bpf_map_key_store(struct bpf_insn_aux_data *aux, u64 state)
(poisoned ? BPF_MAP_KEY_POISON : 0ULL);
}
+static bool bpf_pseudo_call(const struct bpf_insn *insn)
+{
+ return insn->code == (BPF_JMP | BPF_CALL) &&
+ insn->src_reg == BPF_PSEUDO_CALL;
+}
+
struct bpf_call_arg_meta {
struct bpf_map *map_ptr;
bool raw_mode;
@@ -1073,6 +1079,51 @@ static void mark_reg_known_zero(struct bpf_verifier_env *env,
__mark_reg_known_zero(regs + regno);
}
+static void mark_ptr_not_null_reg(struct bpf_reg_state *reg)
+{
+ switch (reg->type) {
+ case PTR_TO_MAP_VALUE_OR_NULL: {
+ const struct bpf_map *map = reg->map_ptr;
+
+ if (map->inner_map_meta) {
+ reg->type = CONST_PTR_TO_MAP;
+ reg->map_ptr = map->inner_map_meta;
+ } else if (map->map_type == BPF_MAP_TYPE_XSKMAP) {
+ reg->type = PTR_TO_XDP_SOCK;
+ } else if (map->map_type == BPF_MAP_TYPE_SOCKMAP ||
+ map->map_type == BPF_MAP_TYPE_SOCKHASH) {
+ reg->type = PTR_TO_SOCKET;
+ } else {
+ reg->type = PTR_TO_MAP_VALUE;
+ }
+ break;
+ }
+ case PTR_TO_SOCKET_OR_NULL:
+ reg->type = PTR_TO_SOCKET;
+ break;
+ case PTR_TO_SOCK_COMMON_OR_NULL:
+ reg->type = PTR_TO_SOCK_COMMON;
+ break;
+ case PTR_TO_TCP_SOCK_OR_NULL:
+ reg->type = PTR_TO_TCP_SOCK;
+ break;
+ case PTR_TO_BTF_ID_OR_NULL:
+ reg->type = PTR_TO_BTF_ID;
+ break;
+ case PTR_TO_MEM_OR_NULL:
+ reg->type = PTR_TO_MEM;
+ break;
+ case PTR_TO_RDONLY_BUF_OR_NULL:
+ reg->type = PTR_TO_RDONLY_BUF;
+ break;
+ case PTR_TO_RDWR_BUF_OR_NULL:
+ reg->type = PTR_TO_RDWR_BUF;
+ break;
+ default:
+ WARN_ON("unknown nullable register type");
+ }
+}
+
static bool reg_is_pkt_pointer(const struct bpf_reg_state *reg)
{
return type_is_pkt_pointer(reg->type);
@@ -1486,9 +1537,7 @@ static int check_subprogs(struct bpf_verifier_env *env)
/* determine subprog starts. The end is one before the next starts */
for (i = 0; i < insn_cnt; i++) {
- if (insn[i].code != (BPF_JMP | BPF_CALL))
- continue;
- if (insn[i].src_reg != BPF_PSEUDO_CALL)
+ if (!bpf_pseudo_call(insn + i))
continue;
if (!env->bpf_capable) {
verbose(env,
@@ -2271,12 +2320,14 @@ static void save_register_state(struct bpf_func_state *state,
state->stack[spi].slot_type[i] = STACK_SPILL;
}
-/* check_stack_read/write functions track spill/fill of registers,
+/* check_stack_{read,write}_fixed_off functions track spill/fill of registers,
* stack boundary and alignment are checked in check_mem_access()
*/
-static int check_stack_write(struct bpf_verifier_env *env,
- struct bpf_func_state *state, /* func where register points to */
- int off, int size, int value_regno, int insn_idx)
+static int check_stack_write_fixed_off(struct bpf_verifier_env *env,
+ /* stack frame we're writing to */
+ struct bpf_func_state *state,
+ int off, int size, int value_regno,
+ int insn_idx)
{
struct bpf_func_state *cur; /* state of the current function */
int i, slot = -off - 1, spi = slot / BPF_REG_SIZE, err;
@@ -2402,9 +2453,175 @@ static int check_stack_write(struct bpf_verifier_env *env,
return 0;
}
-static int check_stack_read(struct bpf_verifier_env *env,
- struct bpf_func_state *reg_state /* func where register points to */,
- int off, int size, int value_regno)
+/* Write the stack: 'stack[ptr_regno + off] = value_regno'. 'ptr_regno' is
+ * known to contain a variable offset.
+ * This function checks whether the write is permitted and conservatively
+ * tracks the effects of the write, considering that each stack slot in the
+ * dynamic range is potentially written to.
+ *
+ * 'off' includes 'regno->off'.
+ * 'value_regno' can be -1, meaning that an unknown value is being written to
+ * the stack.
+ *
+ * Spilled pointers in range are not marked as written because we don't know
+ * what's going to be actually written. This means that read propagation for
+ * future reads cannot be terminated by this write.
+ *
+ * For privileged programs, uninitialized stack slots are considered
+ * initialized by this write (even though we don't know exactly what offsets
+ * are going to be written to). The idea is that we don't want the verifier to
+ * reject future reads that access slots written to through variable offsets.
+ */
+static int check_stack_write_var_off(struct bpf_verifier_env *env,
+ /* func where register points to */
+ struct bpf_func_state *state,
+ int ptr_regno, int off, int size,
+ int value_regno, int insn_idx)
+{
+ struct bpf_func_state *cur; /* state of the current function */
+ int min_off, max_off;
+ int i, err;
+ struct bpf_reg_state *ptr_reg = NULL, *value_reg = NULL;
+ bool writing_zero = false;
+ /* set if the fact that we're writing a zero is used to let any
+ * stack slots remain STACK_ZERO
+ */
+ bool zero_used = false;
+
+ cur = env->cur_state->frame[env->cur_state->curframe];
+ ptr_reg = &cur->regs[ptr_regno];
+ min_off = ptr_reg->smin_value + off;
+ max_off = ptr_reg->smax_value + off + size;
+ if (value_regno >= 0)
+ value_reg = &cur->regs[value_regno];
+ if (value_reg && register_is_null(value_reg))
+ writing_zero = true;
+
+ err = realloc_func_state(state, round_up(-min_off, BPF_REG_SIZE),
+ state->acquired_refs, true);
+ if (err)
+ return err;
+
+
+ /* Variable offset writes destroy any spilled pointers in range. */
+ for (i = min_off; i < max_off; i++) {
+ u8 new_type, *stype;
+ int slot, spi;
+
+ slot = -i - 1;
+ spi = slot / BPF_REG_SIZE;
+ stype = &state->stack[spi].slot_type[slot % BPF_REG_SIZE];
+
+ if (!env->allow_ptr_leaks
+ && *stype != NOT_INIT
+ && *stype != SCALAR_VALUE) {
+ /* Reject the write if there's are spilled pointers in
+ * range. If we didn't reject here, the ptr status
+ * would be erased below (even though not all slots are
+ * actually overwritten), possibly opening the door to
+ * leaks.
+ */
+ verbose(env, "spilled ptr in range of var-offset stack write; insn %d, ptr off: %d",
+ insn_idx, i);
+ return -EINVAL;
+ }
+
+ /* Erase all spilled pointers. */
+ state->stack[spi].spilled_ptr.type = NOT_INIT;
+
+ /* Update the slot type. */
+ new_type = STACK_MISC;
+ if (writing_zero && *stype == STACK_ZERO) {
+ new_type = STACK_ZERO;
+ zero_used = true;
+ }
+ /* If the slot is STACK_INVALID, we check whether it's OK to
+ * pretend that it will be initialized by this write. The slot
+ * might not actually be written to, and so if we mark it as
+ * initialized future reads might leak uninitialized memory.
+ * For privileged programs, we will accept such reads to slots
+ * that may or may not be written because, if we're reject
+ * them, the error would be too confusing.
+ */
+ if (*stype == STACK_INVALID && !env->allow_uninit_stack) {
+ verbose(env, "uninit stack in range of var-offset write prohibited for !root; insn %d, off: %d",
+ insn_idx, i);
+ return -EINVAL;
+ }
+ *stype = new_type;
+ }
+ if (zero_used) {
+ /* backtracking doesn't work for STACK_ZERO yet. */
+ err = mark_chain_precision(env, value_regno);
+ if (err)
+ return err;
+ }
+ return 0;
+}
+
+/* When register 'dst_regno' is assigned some values from stack[min_off,
+ * max_off), we set the register's type according to the types of the
+ * respective stack slots. If all the stack values are known to be zeros, then
+ * so is the destination reg. Otherwise, the register is considered to be
+ * SCALAR. This function does not deal with register filling; the caller must
+ * ensure that all spilled registers in the stack range have been marked as
+ * read.
+ */
+static void mark_reg_stack_read(struct bpf_verifier_env *env,
+ /* func where src register points to */
+ struct bpf_func_state *ptr_state,
+ int min_off, int max_off, int dst_regno)
+{
+ struct bpf_verifier_state *vstate = env->cur_state;
+ struct bpf_func_state *state = vstate->frame[vstate->curframe];
+ int i, slot, spi;
+ u8 *stype;
+ int zeros = 0;
+
+ for (i = min_off; i < max_off; i++) {
+ slot = -i - 1;
+ spi = slot / BPF_REG_SIZE;
+ stype = ptr_state->stack[spi].slot_type;
+ if (stype[slot % BPF_REG_SIZE] != STACK_ZERO)
+ break;
+ zeros++;
+ }
+ if (zeros == max_off - min_off) {
+ /* any access_size read into register is zero extended,
+ * so the whole register == const_zero
+ */
+ __mark_reg_const_zero(&state->regs[dst_regno]);
+ /* backtracking doesn't support STACK_ZERO yet,
+ * so mark it precise here, so that later
+ * backtracking can stop here.
+ * Backtracking may not need this if this register
+ * doesn't participate in pointer adjustment.
+ * Forward propagation of precise flag is not
+ * necessary either. This mark is only to stop
+ * backtracking. Any register that contributed
+ * to const 0 was marked precise before spill.
+ */
+ state->regs[dst_regno].precise = true;
+ } else {
+ /* have read misc data from the stack */
+ mark_reg_unknown(env, state->regs, dst_regno);
+ }
+ state->regs[dst_regno].live |= REG_LIVE_WRITTEN;
+}
+
+/* Read the stack at 'off' and put the results into the register indicated by
+ * 'dst_regno'. It handles reg filling if the addressed stack slot is a
+ * spilled reg.
+ *
+ * 'dst_regno' can be -1, meaning that the read value is not going to a
+ * register.
+ *
+ * The access is assumed to be within the current stack bounds.
+ */
+static int check_stack_read_fixed_off(struct bpf_verifier_env *env,
+ /* func where src register points to */
+ struct bpf_func_state *reg_state,
+ int off, int size, int dst_regno)
{
struct bpf_verifier_state *vstate = env->cur_state;
struct bpf_func_state *state = vstate->frame[vstate->curframe];
@@ -2412,11 +2629,6 @@ static int check_stack_read(struct bpf_verifier_env *env,
struct bpf_reg_state *reg;
u8 *stype;
- if (reg_state->allocated_stack <= slot) {
- verbose(env, "invalid read from stack off %d+0 size %d\n",
- off, size);
- return -EACCES;
- }
stype = reg_state->stack[spi].slot_type;
reg = &reg_state->stack[spi].spilled_ptr;
@@ -2427,9 +2639,9 @@ static int check_stack_read(struct bpf_verifier_env *env,
verbose(env, "invalid size of register fill\n");
return -EACCES;
}
- if (value_regno >= 0) {
- mark_reg_unknown(env, state->regs, value_regno);
- state->regs[value_regno].live |= REG_LIVE_WRITTEN;
+ if (dst_regno >= 0) {
+ mark_reg_unknown(env, state->regs, dst_regno);
+ state->regs[dst_regno].live |= REG_LIVE_WRITTEN;
}
mark_reg_read(env, reg, reg->parent, REG_LIVE_READ64);
return 0;
@@ -2441,16 +2653,16 @@ static int check_stack_read(struct bpf_verifier_env *env,
}
}
- if (value_regno >= 0) {
+ if (dst_regno >= 0) {
/* restore register state from stack */
- state->regs[value_regno] = *reg;
+ state->regs[dst_regno] = *reg;
/* mark reg as written since spilled pointer state likely
* has its liveness marks cleared by is_state_visited()
* which resets stack/reg liveness for state transitions
*/
- state->regs[value_regno].live |= REG_LIVE_WRITTEN;
+ state->regs[dst_regno].live |= REG_LIVE_WRITTEN;
} else if (__is_pointer_value(env->allow_ptr_leaks, reg)) {
- /* If value_regno==-1, the caller is asking us whether
+ /* If dst_regno==-1, the caller is asking us whether
* it is acceptable to use this value as a SCALAR_VALUE
* (e.g. for XADD).
* We must not allow unprivileged callers to do that
@@ -2462,70 +2674,167 @@ static int check_stack_read(struct bpf_verifier_env *env,
}
mark_reg_read(env, reg, reg->parent, REG_LIVE_READ64);
} else {
- int zeros = 0;
+ u8 type;
for (i = 0; i < size; i++) {
- if (stype[(slot - i) % BPF_REG_SIZE] == STACK_MISC)
+ type = stype[(slot - i) % BPF_REG_SIZE];
+ if (type == STACK_MISC)
continue;
- if (stype[(slot - i) % BPF_REG_SIZE] == STACK_ZERO) {
- zeros++;
+ if (type == STACK_ZERO)
continue;
- }
verbose(env, "invalid read from stack off %d+%d size %d\n",
off, i, size);
return -EACCES;
}
mark_reg_read(env, reg, reg->parent, REG_LIVE_READ64);
- if (value_regno >= 0) {
- if (zeros == size) {
- /* any size read into register is zero extended,
- * so the whole register == const_zero
- */
- __mark_reg_const_zero(&state->regs[value_regno]);
- /* backtracking doesn't support STACK_ZERO yet,
- * so mark it precise here, so that later
- * backtracking can stop here.
- * Backtracking may not need this if this register
- * doesn't participate in pointer adjustment.
- * Forward propagation of precise flag is not
- * necessary either. This mark is only to stop
- * backtracking. Any register that contributed
- * to const 0 was marked precise before spill.
- */
- state->regs[value_regno].precise = true;
- } else {
- /* have read misc data from the stack */
- mark_reg_unknown(env, state->regs, value_regno);
- }
- state->regs[value_regno].live |= REG_LIVE_WRITTEN;
- }
+ if (dst_regno >= 0)
+ mark_reg_stack_read(env, reg_state, off, off + size, dst_regno);
}
return 0;
}
-static int check_stack_access(struct bpf_verifier_env *env,
- const struct bpf_reg_state *reg,
- int off, int size)
+enum stack_access_src {
+ ACCESS_DIRECT = 1, /* the access is performed by an instruction */
+ ACCESS_HELPER = 2, /* the access is performed by a helper */
+};
+
+static int check_stack_range_initialized(struct bpf_verifier_env *env,
+ int regno, int off, int access_size,
+ bool zero_size_allowed,
+ enum stack_access_src type,
+ struct bpf_call_arg_meta *meta);
+
+static struct bpf_reg_state *reg_state(struct bpf_verifier_env *env, int regno)
{
- /* Stack accesses must be at a fixed offset, so that we
- * can determine what type of data were returned. See
- * check_stack_read().
+ return cur_regs(env) + regno;
+}
+
+/* Read the stack at 'ptr_regno + off' and put the result into the register
+ * 'dst_regno'.
+ * 'off' includes the pointer register's fixed offset(i.e. 'ptr_regno.off'),
+ * but not its variable offset.
+ * 'size' is assumed to be <= reg size and the access is assumed to be aligned.
+ *
+ * As opposed to check_stack_read_fixed_off, this function doesn't deal with
+ * filling registers (i.e. reads of spilled register cannot be detected when
+ * the offset is not fixed). We conservatively mark 'dst_regno' as containing
+ * SCALAR_VALUE. That's why we assert that the 'ptr_regno' has a variable
+ * offset; for a fixed offset check_stack_read_fixed_off should be used
+ * instead.
+ */
+static int check_stack_read_var_off(struct bpf_verifier_env *env,
+ int ptr_regno, int off, int size, int dst_regno)
+{
+ /* The state of the source register. */
+ struct bpf_reg_state *reg = reg_state(env, ptr_regno);
+ struct bpf_func_state *ptr_state = func(env, reg);
+ int err;
+ int min_off, max_off;
+
+ /* Note that we pass a NULL meta, so raw access will not be permitted.
*/
- if (!tnum_is_const(reg->var_off)) {
+ err = check_stack_range_initialized(env, ptr_regno, off, size,
+ false, ACCESS_DIRECT, NULL);
+ if (err)
+ return err;
+
+ min_off = reg->smin_value + off;
+ max_off = reg->smax_value + off;
+ mark_reg_stack_read(env, ptr_state, min_off, max_off + size, dst_regno);
+ return 0;
+}
+
+/* check_stack_read dispatches to check_stack_read_fixed_off or
+ * check_stack_read_var_off.
+ *
+ * The caller must ensure that the offset falls within the allocated stack
+ * bounds.
+ *
+ * 'dst_regno' is a register which will receive the value from the stack. It
+ * can be -1, meaning that the read value is not going to a register.
+ */
+static int check_stack_read(struct bpf_verifier_env *env,
+ int ptr_regno, int off, int size,
+ int dst_regno)
+{
+ struct bpf_reg_state *reg = reg_state(env, ptr_regno);
+ struct bpf_func_state *state = func(env, reg);
+ int err;
+ /* Some accesses are only permitted with a static offset. */
+ bool var_off = !tnum_is_const(reg->var_off);
+
+ /* The offset is required to be static when reads don't go to a
+ * register, in order to not leak pointers (see
+ * check_stack_read_fixed_off).
+ */
+ if (dst_regno < 0 && var_off) {
char tn_buf[48];
tnum_strn(tn_buf, sizeof(tn_buf), reg->var_off);
- verbose(env, "variable stack access var_off=%s off=%d size=%d\n",
+ verbose(env, "variable offset stack pointer cannot be passed into helper function; var_off=%s off=%d size=%d\n",
tn_buf, off, size);
return -EACCES;
}
+ /* Variable offset is prohibited for unprivileged mode for simplicity
+ * since it requires corresponding support in Spectre masking for stack
+ * ALU. See also retrieve_ptr_limit().
+ */
+ if (!env->bypass_spec_v1 && var_off) {
+ char tn_buf[48];
- if (off >= 0 || off < -MAX_BPF_STACK) {
- verbose(env, "invalid stack off=%d size=%d\n", off, size);
+ tnum_strn(tn_buf, sizeof(tn_buf), reg->var_off);
+ verbose(env, "R%d variable offset stack access prohibited for !root, var_off=%s\n",
+ ptr_regno, tn_buf);
return -EACCES;
}
- return 0;
+ if (!var_off) {
+ off += reg->var_off.value;
+ err = check_stack_read_fixed_off(env, state, off, size,
+ dst_regno);
+ } else {
+ /* Variable offset stack reads need more conservative handling
+ * than fixed offset ones. Note that dst_regno >= 0 on this
+ * branch.
+ */
+ err = check_stack_read_var_off(env, ptr_regno, off, size,
+ dst_regno);
+ }
+ return err;
+}
+
+
+/* check_stack_write dispatches to check_stack_write_fixed_off or
+ * check_stack_write_var_off.
+ *
+ * 'ptr_regno' is the register used as a pointer into the stack.
+ * 'off' includes 'ptr_regno->off', but not its variable offset (if any).
+ * 'value_regno' is the register whose value we're writing to the stack. It can
+ * be -1, meaning that we're not writing from a register.
+ *
+ * The caller must ensure that the offset falls within the maximum stack size.
+ */
+static int check_stack_write(struct bpf_verifier_env *env,
+ int ptr_regno, int off, int size,
+ int value_regno, int insn_idx)
+{
+ struct bpf_reg_state *reg = reg_state(env, ptr_regno);
+ struct bpf_func_state *state = func(env, reg);
+ int err;
+
+ if (tnum_is_const(reg->var_off)) {
+ off += reg->var_off.value;
+ err = check_stack_write_fixed_off(env, state, off, size,
+ value_regno, insn_idx);
+ } else {
+ /* Variable offset stack reads need more conservative handling
+ * than fixed offset ones.
+ */
+ err = check_stack_write_var_off(env, state,
+ ptr_regno, off, size,
+ value_regno, insn_idx);
+ }
+ return err;
}
static int check_map_access_type(struct bpf_verifier_env *env, u32 regno,
@@ -2858,11 +3167,6 @@ static int check_sock_access(struct bpf_verifier_env *env, int insn_idx,
return -EACCES;
}
-static struct bpf_reg_state *reg_state(struct bpf_verifier_env *env, int regno)
-{
- return cur_regs(env) + regno;
-}
-
static bool is_pointer_value(struct bpf_verifier_env *env, int regno)
{
return __is_pointer_value(env->allow_ptr_leaks, reg_state(env, regno));
@@ -2981,8 +3285,8 @@ static int check_ptr_alignment(struct bpf_verifier_env *env,
break;
case PTR_TO_STACK:
pointer_desc = "stack ";
- /* The stack spill tracking logic in check_stack_write()
- * and check_stack_read() relies on stack accesses being
+ /* The stack spill tracking logic in check_stack_write_fixed_off()
+ * and check_stack_read_fixed_off() relies on stack accesses being
* aligned.
*/
strict = true;
@@ -3074,9 +3378,7 @@ process_func:
continue_func:
subprog_end = subprog[idx + 1].start;
for (; i < subprog_end; i++) {
- if (insn[i].code != (BPF_JMP | BPF_CALL))
- continue;
- if (insn[i].src_reg != BPF_PSEUDO_CALL)
+ if (!bpf_pseudo_call(insn + i))
continue;
/* remember insn and function to return to */
ret_insn[frame] = i + 1;
@@ -3400,6 +3702,91 @@ static int check_ptr_to_map_access(struct bpf_verifier_env *env,
return 0;
}
+/* Check that the stack access at the given offset is within bounds. The
+ * maximum valid offset is -1.
+ *
+ * The minimum valid offset is -MAX_BPF_STACK for writes, and
+ * -state->allocated_stack for reads.
+ */
+static int check_stack_slot_within_bounds(int off,
+ struct bpf_func_state *state,
+ enum bpf_access_type t)
+{
+ int min_valid_off;
+
+ if (t == BPF_WRITE)
+ min_valid_off = -MAX_BPF_STACK;
+ else
+ min_valid_off = -state->allocated_stack;
+
+ if (off < min_valid_off || off > -1)
+ return -EACCES;
+ return 0;
+}
+
+/* Check that the stack access at 'regno + off' falls within the maximum stack
+ * bounds.
+ *
+ * 'off' includes `regno->offset`, but not its dynamic part (if any).
+ */
+static int check_stack_access_within_bounds(
+ struct bpf_verifier_env *env,
+ int regno, int off, int access_size,
+ enum stack_access_src src, enum bpf_access_type type)
+{
+ struct bpf_reg_state *regs = cur_regs(env);
+ struct bpf_reg_state *reg = regs + regno;
+ struct bpf_func_state *state = func(env, reg);
+ int min_off, max_off;
+ int err;
+ char *err_extra;
+
+ if (src == ACCESS_HELPER)
+ /* We don't know if helpers are reading or writing (or both). */
+ err_extra = " indirect access to";
+ else if (type == BPF_READ)
+ err_extra = " read from";
+ else
+ err_extra = " write to";
+
+ if (tnum_is_const(reg->var_off)) {
+ min_off = reg->var_off.value + off;
+ if (access_size > 0)
+ max_off = min_off + access_size - 1;
+ else
+ max_off = min_off;
+ } else {
+ if (reg->smax_value >= BPF_MAX_VAR_OFF ||
+ reg->smin_value <= -BPF_MAX_VAR_OFF) {
+ verbose(env, "invalid unbounded variable-offset%s stack R%d\n",
+ err_extra, regno);
+ return -EACCES;
+ }
+ min_off = reg->smin_value + off;
+ if (access_size > 0)
+ max_off = reg->smax_value + off + access_size - 1;
+ else
+ max_off = min_off;
+ }
+
+ err = check_stack_slot_within_bounds(min_off, state, type);
+ if (!err)
+ err = check_stack_slot_within_bounds(max_off, state, type);
+
+ if (err) {
+ if (tnum_is_const(reg->var_off)) {
+ verbose(env, "invalid%s stack R%d off=%d size=%d\n",
+ err_extra, regno, off, access_size);
+ } else {
+ char tn_buf[48];
+
+ tnum_strn(tn_buf, sizeof(tn_buf), reg->var_off);
+ verbose(env, "invalid variable-offset%s stack R%d var_off=%s size=%d\n",
+ err_extra, regno, tn_buf, access_size);
+ }
+ }
+ return err;
+}
/* check whether memory at (regno + off) is accessible for t = (read | write)
* if t==write, value_regno is a register which value is stored into memory
@@ -3515,8 +3902,8 @@ static int check_mem_access(struct bpf_verifier_env *env, int insn_idx, u32 regn
}
} else if (reg->type == PTR_TO_STACK) {
- off += reg->var_off.value;
- err = check_stack_access(env, reg, off, size);
+ /* Basic bounds checks. */
+ err = check_stack_access_within_bounds(env, regno, off, size, ACCESS_DIRECT, t);
if (err)
return err;
@@ -3525,12 +3912,12 @@ static int check_mem_access(struct bpf_verifier_env *env, int insn_idx, u32 regn
if (err)
return err;
- if (t == BPF_WRITE)
- err = check_stack_write(env, state, off, size,
- value_regno, insn_idx);
- else
- err = check_stack_read(env, state, off, size,
+ if (t == BPF_READ)
+ err = check_stack_read(env, regno, off, size,
value_regno);
+ else
+ err = check_stack_write(env, regno, off, size,
+ value_regno, insn_idx);
} else if (reg_is_pkt_pointer(reg)) {
if (t == BPF_WRITE && !may_access_direct_pkt_data(env, NULL, t)) {
verbose(env, "cannot write into packet\n");
@@ -3606,13 +3993,30 @@ static int check_mem_access(struct bpf_verifier_env *env, int insn_idx, u32 regn
return err;
}
-static int check_xadd(struct bpf_verifier_env *env, int insn_idx, struct bpf_insn *insn)
+static int check_atomic(struct bpf_verifier_env *env, int insn_idx, struct bpf_insn *insn)
{
+ int load_reg;
int err;
- if ((BPF_SIZE(insn->code) != BPF_W && BPF_SIZE(insn->code) != BPF_DW) ||
- insn->imm != 0) {
- verbose(env, "BPF_XADD uses reserved fields\n");
+ switch (insn->imm) {
+ case BPF_ADD:
+ case BPF_ADD | BPF_FETCH:
+ case BPF_AND:
+ case BPF_AND | BPF_FETCH:
+ case BPF_OR:
+ case BPF_OR | BPF_FETCH:
+ case BPF_XOR:
+ case BPF_XOR | BPF_FETCH:
+ case BPF_XCHG:
+ case BPF_CMPXCHG:
+ break;
+ default:
+ verbose(env, "BPF_ATOMIC uses invalid atomic opcode %02x\n", insn->imm);
+ return -EINVAL;
+ }
+
+ if (BPF_SIZE(insn->code) != BPF_W && BPF_SIZE(insn->code) != BPF_DW) {
+ verbose(env, "invalid atomic operand size\n");
return -EINVAL;
}
@@ -3626,6 +4030,13 @@ static int check_xadd(struct bpf_verifier_env *env, int insn_idx, struct bpf_ins
if (err)
return err;
+ if (insn->imm == BPF_CMPXCHG) {
+ /* Check comparison of R0 with memory location */
+ err = check_reg_arg(env, BPF_REG_0, SRC_OP);
+ if (err)
+ return err;
+ }
+
if (is_pointer_value(env, insn->src_reg)) {
verbose(env, "R%d leaks addr into mem\n", insn->src_reg);
return -EACCES;
@@ -3635,66 +4046,91 @@ static int check_xadd(struct bpf_verifier_env *env, int insn_idx, struct bpf_ins
is_pkt_reg(env, insn->dst_reg) ||
is_flow_key_reg(env, insn->dst_reg) ||
is_sk_reg(env, insn->dst_reg)) {
- verbose(env, "BPF_XADD stores into R%d %s is not allowed\n",
+ verbose(env, "BPF_ATOMIC stores into R%d %s is not allowed\n",
insn->dst_reg,
reg_type_str[reg_state(env, insn->dst_reg)->type]);
return -EACCES;
}
- /* check whether atomic_add can read the memory */
+ if (insn->imm & BPF_FETCH) {
+ if (insn->imm == BPF_CMPXCHG)
+ load_reg = BPF_REG_0;
+ else
+ load_reg = insn->src_reg;
+
+ /* check and record load of old value */
+ err = check_reg_arg(env, load_reg, DST_OP);
+ if (err)
+ return err;
+ } else {
+ /* This instruction accesses a memory location but doesn't
+ * actually load it into a register.
+ */
+ load_reg = -1;
+ }
+
+ /* check whether we can read the memory */
err = check_mem_access(env, insn_idx, insn->dst_reg, insn->off,
- BPF_SIZE(insn->code), BPF_READ, -1, true);
+ BPF_SIZE(insn->code), BPF_READ, load_reg, true);
if (err)
return err;
- /* check whether atomic_add can write into the same memory */
- return check_mem_access(env, insn_idx, insn->dst_reg, insn->off,
- BPF_SIZE(insn->code), BPF_WRITE, -1, true);
-}
-
-static int __check_stack_boundary(struct bpf_verifier_env *env, u32 regno,
- int off, int access_size,
- bool zero_size_allowed)
-{
- struct bpf_reg_state *reg = reg_state(env, regno);
-
- if (off >= 0 || off < -MAX_BPF_STACK || off + access_size > 0 ||
- access_size < 0 || (access_size == 0 && !zero_size_allowed)) {
- if (tnum_is_const(reg->var_off)) {
- verbose(env, "invalid stack type R%d off=%d access_size=%d\n",
- regno, off, access_size);
- } else {
- char tn_buf[48];
+ /* check whether we can write into the same memory */
+ err = check_mem_access(env, insn_idx, insn->dst_reg, insn->off,
+ BPF_SIZE(insn->code), BPF_WRITE, -1, true);
+ if (err)
+ return err;
- tnum_strn(tn_buf, sizeof(tn_buf), reg->var_off);
- verbose(env, "invalid stack type R%d var_off=%s access_size=%d\n",
- regno, tn_buf, access_size);
- }
- return -EACCES;
- }
return 0;
}
-/* when register 'regno' is passed into function that will read 'access_size'
- * bytes from that pointer, make sure that it's within stack boundary
- * and all elements of stack are initialized.
- * Unlike most pointer bounds-checking functions, this one doesn't take an
- * 'off' argument, so it has to add in reg->off itself.
+/* When register 'regno' is used to read the stack (either directly or through
+ * a helper function) make sure that it's within stack boundary and, depending
+ * on the access type, that all elements of the stack are initialized.
+ *
+ * 'off' includes 'regno->off', but not its dynamic part (if any).
+ *
+ * All registers that have been spilled on the stack in the slots within the
+ * read offsets are marked as read.
*/
-static int check_stack_boundary(struct bpf_verifier_env *env, int regno,
- int access_size, bool zero_size_allowed,
- struct bpf_call_arg_meta *meta)
+static int check_stack_range_initialized(
+ struct bpf_verifier_env *env, int regno, int off,
+ int access_size, bool zero_size_allowed,
+ enum stack_access_src type, struct bpf_call_arg_meta *meta)
{
struct bpf_reg_state *reg = reg_state(env, regno);
struct bpf_func_state *state = func(env, reg);
int err, min_off, max_off, i, j, slot, spi;
+ char *err_extra = type == ACCESS_HELPER ? " indirect" : "";
+ enum bpf_access_type bounds_check_type;
+ /* Some accesses can write anything into the stack, others are
+ * read-only.
+ */
+ bool clobber = false;
+
+ if (access_size == 0 && !zero_size_allowed) {
+ verbose(env, "invalid zero-sized read\n");
+ return -EACCES;
+ }
+
+ if (type == ACCESS_HELPER) {
+ /* The bounds checks for writes are more permissive than for
+ * reads. However, if raw_mode is not set, we'll do extra
+ * checks below.
+ */
+ bounds_check_type = BPF_WRITE;
+ clobber = true;
+ } else {
+ bounds_check_type = BPF_READ;
+ }
+ err = check_stack_access_within_bounds(env, regno, off, access_size,
+ type, bounds_check_type);
+ if (err)
+ return err;
+
if (tnum_is_const(reg->var_off)) {
- min_off = max_off = reg->var_off.value + reg->off;
- err = __check_stack_boundary(env, regno, min_off, access_size,
- zero_size_allowed);
- if (err)
- return err;
+ min_off = max_off = reg->var_off.value + off;
} else {
/* Variable offset is prohibited for unprivileged mode for
* simplicity since it requires corresponding support in
@@ -3705,8 +4141,8 @@ static int check_stack_boundary(struct bpf_verifier_env *env, int regno,
char tn_buf[48];
tnum_strn(tn_buf, sizeof(tn_buf), reg->var_off);
- verbose(env, "R%d indirect variable offset stack access prohibited for !root, var_off=%s\n",
- regno, tn_buf);
+ verbose(env, "R%d%s variable offset stack access prohibited for !root, var_off=%s\n",
+ regno, err_extra, tn_buf);
return -EACCES;
}
/* Only initialized buffer on stack is allowed to be accessed
@@ -3718,28 +4154,8 @@ static int check_stack_boundary(struct bpf_verifier_env *env, int regno,
if (meta && meta->raw_mode)
meta = NULL;
- if (reg->smax_value >= BPF_MAX_VAR_OFF ||
- reg->smax_value <= -BPF_MAX_VAR_OFF) {
- verbose(env, "R%d unbounded indirect variable offset stack access\n",
- regno);
- return -EACCES;
- }
- min_off = reg->smin_value + reg->off;
- max_off = reg->smax_value + reg->off;
- err = __check_stack_boundary(env, regno, min_off, access_size,
- zero_size_allowed);
- if (err) {
- verbose(env, "R%d min value is outside of stack bound\n",
- regno);
- return err;
- }
- err = __check_stack_boundary(env, regno, max_off, access_size,
- zero_size_allowed);
- if (err) {
- verbose(env, "R%d max value is outside of stack bound\n",
- regno);
- return err;
- }
+ min_off = reg->smin_value + off;
+ max_off = reg->smax_value + off;
}
if (meta && meta->raw_mode) {
@@ -3759,8 +4175,10 @@ static int check_stack_boundary(struct bpf_verifier_env *env, int regno,
if (*stype == STACK_MISC)
goto mark;
if (*stype == STACK_ZERO) {
- /* helper can write anything into the stack */
- *stype = STACK_MISC;
+ if (clobber) {
+ /* helper can write anything into the stack */
+ *stype = STACK_MISC;
+ }
goto mark;
}
@@ -3771,22 +4189,24 @@ static int check_stack_boundary(struct bpf_verifier_env *env, int regno,
if (state->stack[spi].slot_type[0] == STACK_SPILL &&
(state->stack[spi].spilled_ptr.type == SCALAR_VALUE ||
env->allow_ptr_leaks)) {
- __mark_reg_unknown(env, &state->stack[spi].spilled_ptr);
- for (j = 0; j < BPF_REG_SIZE; j++)
- state->stack[spi].slot_type[j] = STACK_MISC;
+ if (clobber) {
+ __mark_reg_unknown(env, &state->stack[spi].spilled_ptr);
+ for (j = 0; j < BPF_REG_SIZE; j++)
+ state->stack[spi].slot_type[j] = STACK_MISC;
+ }
goto mark;
}
err:
if (tnum_is_const(reg->var_off)) {
- verbose(env, "invalid indirect read from stack off %d+%d size %d\n",
- min_off, i - min_off, access_size);
+ verbose(env, "invalid%s read from stack R%d off %d+%d size %d\n",
+ err_extra, regno, min_off, i - min_off, access_size);
} else {
char tn_buf[48];
tnum_strn(tn_buf, sizeof(tn_buf), reg->var_off);
- verbose(env, "invalid indirect read from stack var_off %s+%d size %d\n",
- tn_buf, i - min_off, access_size);
+ verbose(env, "invalid%s read from stack R%d var_off %s+%d size %d\n",
+ err_extra, regno, tn_buf, i - min_off, access_size);
}
return -EACCES;
mark:
@@ -3835,8 +4255,10 @@ static int check_helper_mem_access(struct bpf_verifier_env *env, int regno,
"rdwr",
&env->prog->aux->max_rdwr_access);
case PTR_TO_STACK:
- return check_stack_boundary(env, regno, access_size,
- zero_size_allowed, meta);
+ return check_stack_range_initialized(
+ env,
+ regno, reg->off, access_size,
+ zero_size_allowed, ACCESS_HELPER, meta);
default: /* scalar_value or invalid ptr */
/* Allow zero-byte read from NULL, regardless of pointer type */
if (zero_size_allowed && access_size == 0 &&
@@ -3850,6 +4272,29 @@ static int check_helper_mem_access(struct bpf_verifier_env *env, int regno,
}
}
+int check_mem_reg(struct bpf_verifier_env *env, struct bpf_reg_state *reg,
+ u32 regno, u32 mem_size)
+{
+ if (register_is_null(reg))
+ return 0;
+
+ if (reg_type_may_be_null(reg->type)) {
+ /* Assuming that the register contains a value check if the memory
+ * access is safe. Temporarily save and restore the register's state as
+ * the conversion shouldn't be visible to a caller.
+ */
+ const struct bpf_reg_state saved_reg = *reg;
+ int rv;
+
+ mark_ptr_not_null_reg(reg);
+ rv = check_helper_mem_access(env, regno, mem_size, true, NULL);
+ *reg = saved_reg;
+ return rv;
+ }
+
+ return check_helper_mem_access(env, regno, mem_size, true, NULL);
+}
+
/* Implementation details:
* bpf_map_lookup returns PTR_TO_MAP_VALUE_OR_NULL
* Two bpf_map_lookups (even with the same key) will have different reg->id.
@@ -4321,7 +4766,7 @@ skip_type_check:
err = mark_chain_precision(env, regno);
} else if (arg_type_is_alloc_size(arg_type)) {
if (!tnum_is_const(reg->var_off)) {
- verbose(env, "R%d unbounded size, use 'var &= const' or 'if (var < const)'\n",
+ verbose(env, "R%d is not a known constant'\n",
regno);
return -EACCES;
}
@@ -4834,8 +5279,9 @@ static int check_func_call(struct bpf_verifier_env *env, struct bpf_insn *insn,
subprog);
clear_caller_saved_regs(env, caller->regs);
- /* All global functions return SCALAR_VALUE */
+ /* All global functions return a 64-bit SCALAR_VALUE */
mark_reg_unknown(env, caller->regs, BPF_REG_0);
+ caller->regs[BPF_REG_0].subreg_def = DEF_NOT_SUBREG;
/* continue with next insn after call */
return 0;
@@ -5500,6 +5946,41 @@ do_sim:
return !ret ? -EFAULT : 0;
}
+/* check that stack access falls within stack limits and that 'reg' doesn't
+ * have a variable offset.
+ *
+ * Variable offset is prohibited for unprivileged mode for simplicity since it
+ * requires corresponding support in Spectre masking for stack ALU. See also
+ * retrieve_ptr_limit().
+ *
+ *
+ * 'off' includes 'reg->off'.
+ */
+static int check_stack_access_for_ptr_arithmetic(
+ struct bpf_verifier_env *env,
+ int regno,
+ const struct bpf_reg_state *reg,
+ int off)
+{
+ if (!tnum_is_const(reg->var_off)) {
+ char tn_buf[48];
+
+ tnum_strn(tn_buf, sizeof(tn_buf), reg->var_off);
+ verbose(env, "R%d variable stack access prohibited for !root, var_off=%s off=%d\n",
+ regno, tn_buf, off);
+ return -EACCES;
+ }
+
+ if (off >= 0 || off < -MAX_BPF_STACK) {
+ verbose(env, "R%d stack pointer arithmetic goes out of range, "
+ "prohibited for !root; off=%d\n", regno, off);
+ return -EACCES;
+ }
+
+ return 0;
+}
+
+
/* Handles arithmetic on a pointer and a scalar: computes new min/max and var_off.
* Caller should also handle BPF_MOV case separately.
* If we return -EACCES, caller may want to try again treating pointer as a
@@ -5743,10 +6224,9 @@ static int adjust_ptr_min_max_vals(struct bpf_verifier_env *env,
"prohibited for !root\n", dst);
return -EACCES;
} else if (dst_reg->type == PTR_TO_STACK &&
- check_stack_access(env, dst_reg, dst_reg->off +
- dst_reg->var_off.value, 1)) {
- verbose(env, "R%d stack pointer arithmetic goes out of range, "
- "prohibited for !root\n", dst);
+ check_stack_access_for_ptr_arithmetic(
+ env, dst, dst_reg, dst_reg->off +
+ dst_reg->var_off.value)) {
return -EACCES;
}
}
@@ -6225,7 +6705,7 @@ static void scalar32_min_max_rsh(struct bpf_reg_state *dst_reg,
* 3) the signed bounds cross zero, so they tell us nothing
* about the result
* If the value in dst_reg is known nonnegative, then again the
- * unsigned bounts capture the signed bounds.
+ * unsigned bounds capture the signed bounds.
* Thus, in all cases it suffices to blow away our signed bounds
* and rely on inferring new ones from the unsigned bounds and
* var_off of the result.
@@ -6256,7 +6736,7 @@ static void scalar_min_max_rsh(struct bpf_reg_state *dst_reg,
* 3) the signed bounds cross zero, so they tell us nothing
* about the result
* If the value in dst_reg is known nonnegative, then again the
- * unsigned bounts capture the signed bounds.
+ * unsigned bounds capture the signed bounds.
* Thus, in all cases it suffices to blow away our signed bounds
* and rely on inferring new ones from the unsigned bounds and
* var_off of the result.
@@ -6877,7 +7357,7 @@ static int is_branch32_taken(struct bpf_reg_state *reg, u32 val, u8 opcode)
case BPF_JSGT:
if (reg->s32_min_value > sval)
return 1;
- else if (reg->s32_max_value < sval)
+ else if (reg->s32_max_value <= sval)
return 0;
break;
case BPF_JLT:
@@ -6950,7 +7430,7 @@ static int is_branch64_taken(struct bpf_reg_state *reg, u64 val, u8 opcode)
case BPF_JSGT:
if (reg->smin_value > sval)
return 1;
- else if (reg->smax_value < sval)
+ else if (reg->smax_value <= sval)
return 0;
break;
case BPF_JLT:
@@ -7326,43 +7806,19 @@ static void mark_ptr_or_null_reg(struct bpf_func_state *state,
}
if (is_null) {
reg->type = SCALAR_VALUE;
- } else if (reg->type == PTR_TO_MAP_VALUE_OR_NULL) {
- const struct bpf_map *map = reg->map_ptr;
-
- if (map->inner_map_meta) {
- reg->type = CONST_PTR_TO_MAP;
- reg->map_ptr = map->inner_map_meta;
- } else if (map->map_type == BPF_MAP_TYPE_XSKMAP) {
- reg->type = PTR_TO_XDP_SOCK;
- } else if (map->map_type == BPF_MAP_TYPE_SOCKMAP ||
- map->map_type == BPF_MAP_TYPE_SOCKHASH) {
- reg->type = PTR_TO_SOCKET;
- } else {
- reg->type = PTR_TO_MAP_VALUE;
- }
- } else if (reg->type == PTR_TO_SOCKET_OR_NULL) {
- reg->type = PTR_TO_SOCKET;
- } else if (reg->type == PTR_TO_SOCK_COMMON_OR_NULL) {
- reg->type = PTR_TO_SOCK_COMMON;
- } else if (reg->type == PTR_TO_TCP_SOCK_OR_NULL) {
- reg->type = PTR_TO_TCP_SOCK;
- } else if (reg->type == PTR_TO_BTF_ID_OR_NULL) {
- reg->type = PTR_TO_BTF_ID;
- } else if (reg->type == PTR_TO_MEM_OR_NULL) {
- reg->type = PTR_TO_MEM;
- } else if (reg->type == PTR_TO_RDONLY_BUF_OR_NULL) {
- reg->type = PTR_TO_RDONLY_BUF;
- } else if (reg->type == PTR_TO_RDWR_BUF_OR_NULL) {
- reg->type = PTR_TO_RDWR_BUF;
- }
- if (is_null) {
/* We don't need id and ref_obj_id from this point
* onwards anymore, thus we should better reset it,
* so that state pruning has chances to take effect.
*/
reg->id = 0;
reg->ref_obj_id = 0;
- } else if (!reg_may_point_to_spin_lock(reg)) {
+
+ return;
+ }
+
+ mark_ptr_not_null_reg(reg);
+
+ if (!reg_may_point_to_spin_lock(reg)) {
/* For not-NULL ptr, reg->ref_obj_id will be reset
* in release_reg_references().
*
@@ -7945,6 +8401,9 @@ static int check_return_code(struct bpf_verifier_env *env)
env->prog->expected_attach_type == BPF_CGROUP_INET4_GETSOCKNAME ||
env->prog->expected_attach_type == BPF_CGROUP_INET6_GETSOCKNAME)
range = tnum_range(1, 1);
+ if (env->prog->expected_attach_type == BPF_CGROUP_INET4_BIND ||
+ env->prog->expected_attach_type == BPF_CGROUP_INET6_BIND)
+ range = tnum_range(0, 3);
break;
case BPF_PROG_TYPE_CGROUP_SKB:
if (env->prog->expected_attach_type == BPF_CGROUP_INET_EGRESS) {
@@ -8590,7 +9049,11 @@ static bool range_within(struct bpf_reg_state *old,
return old->umin_value <= cur->umin_value &&
old->umax_value >= cur->umax_value &&
old->smin_value <= cur->smin_value &&
- old->smax_value >= cur->smax_value;
+ old->smax_value >= cur->smax_value &&
+ old->u32_min_value <= cur->u32_min_value &&
+ old->u32_max_value >= cur->u32_max_value &&
+ old->s32_min_value <= cur->s32_min_value &&
+ old->s32_max_value >= cur->s32_max_value;
}
/* Maximum number of register states that can exist at once */
@@ -9526,14 +9989,19 @@ static int do_check(struct bpf_verifier_env *env)
} else if (class == BPF_STX) {
enum bpf_reg_type *prev_dst_type, dst_reg_type;
- if (BPF_MODE(insn->code) == BPF_XADD) {
- err = check_xadd(env, env->insn_idx, insn);
+ if (BPF_MODE(insn->code) == BPF_ATOMIC) {
+ err = check_atomic(env, env->insn_idx, insn);
if (err)
return err;
env->insn_idx++;
continue;
}
+ if (BPF_MODE(insn->code) != BPF_MEM || insn->imm != 0) {
+ verbose(env, "BPF_STX uses reserved fields\n");
+ return -EINVAL;
+ }
+
/* check src1 operand */
err = check_reg_arg(env, insn->src_reg, SRC_OP);
if (err)
@@ -9705,6 +10173,36 @@ process_bpf_exit:
return 0;
}
+static int find_btf_percpu_datasec(struct btf *btf)
+{
+ const struct btf_type *t;
+ const char *tname;
+ int i, n;
+
+ /*
+ * Both vmlinux and module each have their own ".data..percpu"
+ * DATASECs in BTF. So for module's case, we need to skip vmlinux BTF
+ * types to look at only module's own BTF types.
+ */
+ n = btf_nr_types(btf);
+ if (btf_is_module(btf))
+ i = btf_nr_types(btf_vmlinux);
+ else
+ i = 1;
+
+ for(; i < n; i++) {
+ t = btf_type_by_id(btf, i);
+ if (BTF_INFO_KIND(t->info) != BTF_KIND_DATASEC)
+ continue;
+
+ tname = btf_name_by_offset(btf, t->name_off);
+ if (!strcmp(tname, ".data..percpu"))
+ return i;
+ }
+
+ return -ENOENT;
+}
+
/* replace pseudo btf_id with kernel symbol address */
static int check_pseudo_btf_id(struct bpf_verifier_env *env,
struct bpf_insn *insn,
@@ -9712,48 +10210,57 @@ static int check_pseudo_btf_id(struct bpf_verifier_env *env,
{
const struct btf_var_secinfo *vsi;
const struct btf_type *datasec;
+ struct btf_mod_pair *btf_mod;
const struct btf_type *t;
const char *sym_name;
bool percpu = false;
u32 type, id = insn->imm;
+ struct btf *btf;
s32 datasec_id;
u64 addr;
- int i;
+ int i, btf_fd, err;
- if (!btf_vmlinux) {
- verbose(env, "kernel is missing BTF, make sure CONFIG_DEBUG_INFO_BTF=y is specified in Kconfig.\n");
- return -EINVAL;
- }
-
- if (insn[1].imm != 0) {
- verbose(env, "reserved field (insn[1].imm) is used in pseudo_btf_id ldimm64 insn.\n");
- return -EINVAL;
+ btf_fd = insn[1].imm;
+ if (btf_fd) {
+ btf = btf_get_by_fd(btf_fd);
+ if (IS_ERR(btf)) {
+ verbose(env, "invalid module BTF object FD specified.\n");
+ return -EINVAL;
+ }
+ } else {
+ if (!btf_vmlinux) {
+ verbose(env, "kernel is missing BTF, make sure CONFIG_DEBUG_INFO_BTF=y is specified in Kconfig.\n");
+ return -EINVAL;
+ }
+ btf = btf_vmlinux;
+ btf_get(btf);
}
- t = btf_type_by_id(btf_vmlinux, id);
+ t = btf_type_by_id(btf, id);
if (!t) {
verbose(env, "ldimm64 insn specifies invalid btf_id %d.\n", id);
- return -ENOENT;
+ err = -ENOENT;
+ goto err_put;
}
if (!btf_type_is_var(t)) {
- verbose(env, "pseudo btf_id %d in ldimm64 isn't KIND_VAR.\n",
- id);
- return -EINVAL;
+ verbose(env, "pseudo btf_id %d in ldimm64 isn't KIND_VAR.\n", id);
+ err = -EINVAL;
+ goto err_put;
}
- sym_name = btf_name_by_offset(btf_vmlinux, t->name_off);
+ sym_name = btf_name_by_offset(btf, t->name_off);
addr = kallsyms_lookup_name(sym_name);
if (!addr) {
verbose(env, "ldimm64 failed to find the address for kernel symbol '%s'.\n",
sym_name);
- return -ENOENT;
+ err = -ENOENT;
+ goto err_put;
}
- datasec_id = btf_find_by_name_kind(btf_vmlinux, ".data..percpu",
- BTF_KIND_DATASEC);
+ datasec_id = find_btf_percpu_datasec(btf);
if (datasec_id > 0) {
- datasec = btf_type_by_id(btf_vmlinux, datasec_id);
+ datasec = btf_type_by_id(btf, datasec_id);
for_each_vsi(i, datasec, vsi) {
if (vsi->type == id) {
percpu = true;
@@ -9766,10 +10273,10 @@ static int check_pseudo_btf_id(struct bpf_verifier_env *env,
insn[1].imm = addr >> 32;
type = t->type;
- t = btf_type_skip_modifiers(btf_vmlinux, type, NULL);
+ t = btf_type_skip_modifiers(btf, type, NULL);
if (percpu) {
aux->btf_var.reg_type = PTR_TO_PERCPU_BTF_ID;
- aux->btf_var.btf = btf_vmlinux;
+ aux->btf_var.btf = btf;
aux->btf_var.btf_id = type;
} else if (!btf_type_is_struct(t)) {
const struct btf_type *ret;
@@ -9777,21 +10284,54 @@ static int check_pseudo_btf_id(struct bpf_verifier_env *env,
u32 tsize;
/* resolve the type size of ksym. */
- ret = btf_resolve_size(btf_vmlinux, t, &tsize);
+ ret = btf_resolve_size(btf, t, &tsize);
if (IS_ERR(ret)) {
- tname = btf_name_by_offset(btf_vmlinux, t->name_off);
+ tname = btf_name_by_offset(btf, t->name_off);
verbose(env, "ldimm64 unable to resolve the size of type '%s': %ld\n",
tname, PTR_ERR(ret));
- return -EINVAL;
+ err = -EINVAL;
+ goto err_put;
}
aux->btf_var.reg_type = PTR_TO_MEM;
aux->btf_var.mem_size = tsize;
} else {
aux->btf_var.reg_type = PTR_TO_BTF_ID;
- aux->btf_var.btf = btf_vmlinux;
+ aux->btf_var.btf = btf;
aux->btf_var.btf_id = type;
}
+
+ /* check whether we recorded this BTF (and maybe module) already */
+ for (i = 0; i < env->used_btf_cnt; i++) {
+ if (env->used_btfs[i].btf == btf) {
+ btf_put(btf);
+ return 0;
+ }
+ }
+
+ if (env->used_btf_cnt >= MAX_USED_BTFS) {
+ err = -E2BIG;
+ goto err_put;
+ }
+
+ btf_mod = &env->used_btfs[env->used_btf_cnt];
+ btf_mod->btf = btf;
+ btf_mod->module = NULL;
+
+ /* if we reference variables from kernel module, bump its refcount */
+ if (btf_is_module(btf)) {
+ btf_mod->module = btf_try_get_module(btf);
+ if (!btf_mod->module) {
+ err = -ENXIO;
+ goto err_put;
+ }
+ }
+
+ env->used_btf_cnt++;
+
return 0;
+err_put:
+ btf_put(btf);
+ return err;
}
static int check_map_prealloc(struct bpf_map *map)
@@ -9893,15 +10433,22 @@ static int check_map_prog_compatibility(struct bpf_verifier_env *env,
case BPF_MAP_TYPE_HASH:
case BPF_MAP_TYPE_LRU_HASH:
case BPF_MAP_TYPE_ARRAY:
+ case BPF_MAP_TYPE_PERCPU_HASH:
+ case BPF_MAP_TYPE_PERCPU_ARRAY:
+ case BPF_MAP_TYPE_LRU_PERCPU_HASH:
+ case BPF_MAP_TYPE_ARRAY_OF_MAPS:
+ case BPF_MAP_TYPE_HASH_OF_MAPS:
if (!is_preallocated_map(map)) {
verbose(env,
- "Sleepable programs can only use preallocated hash maps\n");
+ "Sleepable programs can only use preallocated maps\n");
return -EINVAL;
}
break;
+ case BPF_MAP_TYPE_RINGBUF:
+ break;
default:
verbose(env,
- "Sleepable programs can only use array and hash maps\n");
+ "Sleepable programs can only use array, hash, and ringbuf maps\n");
return -EINVAL;
}
@@ -9938,13 +10485,6 @@ static int resolve_pseudo_ldimm64(struct bpf_verifier_env *env)
return -EINVAL;
}
- if (BPF_CLASS(insn->code) == BPF_STX &&
- ((BPF_MODE(insn->code) != BPF_MEM &&
- BPF_MODE(insn->code) != BPF_XADD) || insn->imm != 0)) {
- verbose(env, "BPF_STX uses reserved fields\n");
- return -EINVAL;
- }
-
if (insn[0].code == (BPF_LD | BPF_IMM | BPF_DW)) {
struct bpf_insn_aux_data *aux;
struct bpf_map *map;
@@ -10088,6 +10628,13 @@ static void release_maps(struct bpf_verifier_env *env)
env->used_map_cnt);
}
+/* drop refcnt of maps used by the rejected program */
+static void release_btfs(struct bpf_verifier_env *env)
+{
+ __bpf_free_used_btfs(env->prog->aux, env->used_btfs,
+ env->used_btf_cnt);
+}
+
/* convert pseudo BPF_LD_IMM64 into generic BPF_LD_IMM64 */
static void convert_pseudo_ld_imm64(struct bpf_verifier_env *env)
{
@@ -10459,6 +11006,7 @@ static int opt_subreg_zext_lo32_rnd_hi32(struct bpf_verifier_env *env,
for (i = 0; i < len; i++) {
int adj_idx = i + delta;
struct bpf_insn insn;
+ u8 load_reg;
insn = insns[adj_idx];
if (!aux[adj_idx].zext_dst) {
@@ -10501,9 +11049,27 @@ static int opt_subreg_zext_lo32_rnd_hi32(struct bpf_verifier_env *env,
if (!bpf_jit_needs_zext())
continue;
+ /* zext_dst means that we want to zero-extend whatever register
+ * the insn defines, which is dst_reg most of the time, with
+ * the notable exception of BPF_STX + BPF_ATOMIC + BPF_FETCH.
+ */
+ if (BPF_CLASS(insn.code) == BPF_STX &&
+ BPF_MODE(insn.code) == BPF_ATOMIC) {
+ /* BPF_STX + BPF_ATOMIC insns without BPF_FETCH do not
+ * define any registers, therefore zext_dst cannot be
+ * set.
+ */
+ if (WARN_ON(!(insn.imm & BPF_FETCH)))
+ return -EINVAL;
+ load_reg = insn.imm == BPF_CMPXCHG ? BPF_REG_0
+ : insn.src_reg;
+ } else {
+ load_reg = insn.dst_reg;
+ }
+
zext_patch[0] = insn;
- zext_patch[1].dst_reg = insn.dst_reg;
- zext_patch[1].src_reg = insn.dst_reg;
+ zext_patch[1].dst_reg = load_reg;
+ zext_patch[1].src_reg = load_reg;
patch = zext_patch;
patch_len = 2;
apply_patch_buffer:
@@ -10719,8 +11285,7 @@ static int jit_subprogs(struct bpf_verifier_env *env)
return 0;
for (i = 0, insn = prog->insnsi; i < prog->len; i++, insn++) {
- if (insn->code != (BPF_JMP | BPF_CALL) ||
- insn->src_reg != BPF_PSEUDO_CALL)
+ if (!bpf_pseudo_call(insn))
continue;
/* Upon error here we cannot fall back to interpreter but
* need a hard reject of the program. Thus -EFAULT is
@@ -10761,7 +11326,7 @@ static int jit_subprogs(struct bpf_verifier_env *env)
/* BPF_PROG_RUN doesn't call subprogs directly,
* hence main prog stats include the runtime of subprogs.
* subprogs don't have IDs and not reachable via prog_get_next_id
- * func[i]->aux->stats will never be accessed and stays NULL
+ * func[i]->stats will never be accessed and stays NULL
*/
func[i] = bpf_prog_alloc_no_stats(bpf_prog_size(len), GFP_USER);
if (!func[i])
@@ -10849,8 +11414,7 @@ static int jit_subprogs(struct bpf_verifier_env *env)
for (i = 0; i < env->subprog_cnt; i++) {
insn = func[i]->insnsi;
for (j = 0; j < func[i]->len; j++, insn++) {
- if (insn->code != (BPF_JMP | BPF_CALL) ||
- insn->src_reg != BPF_PSEUDO_CALL)
+ if (!bpf_pseudo_call(insn))
continue;
subprog = insn->off;
insn->imm = BPF_CAST_CALL(func[subprog]->bpf_func) -
@@ -10895,8 +11459,7 @@ static int jit_subprogs(struct bpf_verifier_env *env)
* later look the same as if they were interpreted only.
*/
for (i = 0, insn = prog->insnsi; i < prog->len; i++, insn++) {
- if (insn->code != (BPF_JMP | BPF_CALL) ||
- insn->src_reg != BPF_PSEUDO_CALL)
+ if (!bpf_pseudo_call(insn))
continue;
insn->off = env->insn_aux_data[i].call_imm;
subprog = find_subprog(env, i + insn->off + 1);
@@ -10925,8 +11488,7 @@ out_undo_insn:
/* cleanup main prog to be interpreted */
prog->jit_requested = 0;
for (i = 0, insn = prog->insnsi; i < prog->len; i++, insn++) {
- if (insn->code != (BPF_JMP | BPF_CALL) ||
- insn->src_reg != BPF_PSEUDO_CALL)
+ if (!bpf_pseudo_call(insn))
continue;
insn->off = 0;
insn->imm = env->insn_aux_data[i].call_imm;
@@ -10961,8 +11523,7 @@ static int fixup_call_args(struct bpf_verifier_env *env)
return -EINVAL;
}
for (i = 0; i < prog->len; i++, insn++) {
- if (insn->code != (BPF_JMP | BPF_CALL) ||
- insn->src_reg != BPF_PSEUDO_CALL)
+ if (!bpf_pseudo_call(insn))
continue;
depth = get_callee_stack_depth(env, insn, i);
if (depth < 0)
@@ -10999,30 +11560,30 @@ static int fixup_bpf_calls(struct bpf_verifier_env *env)
insn->code == (BPF_ALU | BPF_MOD | BPF_X) ||
insn->code == (BPF_ALU | BPF_DIV | BPF_X)) {
bool is64 = BPF_CLASS(insn->code) == BPF_ALU64;
- struct bpf_insn mask_and_div[] = {
- BPF_MOV32_REG(insn->src_reg, insn->src_reg),
- /* Rx div 0 -> 0 */
- BPF_JMP_IMM(BPF_JNE, insn->src_reg, 0, 2),
+ bool isdiv = BPF_OP(insn->code) == BPF_DIV;
+ struct bpf_insn *patchlet;
+ struct bpf_insn chk_and_div[] = {
+ /* [R,W]x div 0 -> 0 */
+ BPF_RAW_INSN((is64 ? BPF_JMP : BPF_JMP32) |
+ BPF_JNE | BPF_K, insn->src_reg,
+ 0, 2, 0),
BPF_ALU32_REG(BPF_XOR, insn->dst_reg, insn->dst_reg),
BPF_JMP_IMM(BPF_JA, 0, 0, 1),
*insn,
};
- struct bpf_insn mask_and_mod[] = {
- BPF_MOV32_REG(insn->src_reg, insn->src_reg),
- /* Rx mod 0 -> Rx */
- BPF_JMP_IMM(BPF_JEQ, insn->src_reg, 0, 1),
+ struct bpf_insn chk_and_mod[] = {
+ /* [R,W]x mod 0 -> [R,W]x */
+ BPF_RAW_INSN((is64 ? BPF_JMP : BPF_JMP32) |
+ BPF_JEQ | BPF_K, insn->src_reg,
+ 0, 1 + (is64 ? 0 : 1), 0),
*insn,
+ BPF_JMP_IMM(BPF_JA, 0, 0, 1),
+ BPF_MOV32_REG(insn->dst_reg, insn->dst_reg),
};
- struct bpf_insn *patchlet;
- if (insn->code == (BPF_ALU64 | BPF_DIV | BPF_X) ||
- insn->code == (BPF_ALU | BPF_DIV | BPF_X)) {
- patchlet = mask_and_div + (is64 ? 1 : 0);
- cnt = ARRAY_SIZE(mask_and_div) - (is64 ? 1 : 0);
- } else {
- patchlet = mask_and_mod + (is64 ? 1 : 0);
- cnt = ARRAY_SIZE(mask_and_mod) - (is64 ? 1 : 0);
- }
+ patchlet = isdiv ? chk_and_div : chk_and_mod;
+ cnt = isdiv ? ARRAY_SIZE(chk_and_div) :
+ ARRAY_SIZE(chk_and_mod) - (is64 ? 2 : 0);
new_prog = bpf_patch_insn_data(env, i + delta, patchlet, cnt);
if (!new_prog)
@@ -11427,6 +11988,13 @@ static int do_check_common(struct bpf_verifier_env *env, int subprog)
mark_reg_known_zero(env, regs, i);
else if (regs[i].type == SCALAR_VALUE)
mark_reg_unknown(env, regs, i);
+ else if (regs[i].type == PTR_TO_MEM_OR_NULL) {
+ const u32 mem_size = regs[i].mem_size;
+
+ mark_reg_known_zero(env, regs, i);
+ regs[i].mem_size = mem_size;
+ regs[i].id = ++env->id_gen;
+ }
}
} else {
/* 1st arg to a function */
@@ -12005,6 +12573,7 @@ int bpf_check(struct bpf_prog **prog, union bpf_attr *attr,
env->strict_alignment = false;
env->allow_ptr_leaks = bpf_allow_ptr_leaks();
+ env->allow_uninit_stack = bpf_allow_uninit_stack();
env->allow_ptr_to_map_access = bpf_allow_ptr_to_map_access();
env->bypass_spec_v1 = bpf_bypass_spec_v1();
env->bypass_spec_v4 = bpf_bypass_spec_v4();
@@ -12100,7 +12669,10 @@ skip_full_check:
goto err_release_maps;
}
- if (ret == 0 && env->used_map_cnt) {
+ if (ret)
+ goto err_release_maps;
+
+ if (env->used_map_cnt) {
/* if program passed verifier, update used_maps in bpf_prog_info */
env->prog->aux->used_maps = kmalloc_array(env->used_map_cnt,
sizeof(env->used_maps[0]),
@@ -12114,15 +12686,29 @@ skip_full_check:
memcpy(env->prog->aux->used_maps, env->used_maps,
sizeof(env->used_maps[0]) * env->used_map_cnt);
env->prog->aux->used_map_cnt = env->used_map_cnt;
+ }
+ if (env->used_btf_cnt) {
+ /* if program passed verifier, update used_btfs in bpf_prog_aux */
+ env->prog->aux->used_btfs = kmalloc_array(env->used_btf_cnt,
+ sizeof(env->used_btfs[0]),
+ GFP_KERNEL);
+ if (!env->prog->aux->used_btfs) {
+ ret = -ENOMEM;
+ goto err_release_maps;
+ }
+ memcpy(env->prog->aux->used_btfs, env->used_btfs,
+ sizeof(env->used_btfs[0]) * env->used_btf_cnt);
+ env->prog->aux->used_btf_cnt = env->used_btf_cnt;
+ }
+ if (env->used_map_cnt || env->used_btf_cnt) {
/* program is valid. Convert pseudo bpf_ld_imm64 into generic
* bpf_ld_imm64 instructions
*/
convert_pseudo_ld_imm64(env);
}
- if (ret == 0)
- adjust_btf_func(env);
+ adjust_btf_func(env);
err_release_maps:
if (!env->prog->aux->used_maps)
@@ -12130,6 +12716,8 @@ err_release_maps:
* them now. Otherwise free_used_maps() will release them.
*/
release_maps(env);
+ if (!env->prog->aux->used_btfs)
+ release_btfs(env);
/* extension progs temporarily inherit the attach_type of their targets
for verification purposes, so set it back to zero before returning
generated by cgit v1.2.3 (git 2.39.1) at 2024-11-14 07:42:50 +0000