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-rw-r--r--kernel/bpf/Kconfig1
-rw-r--r--kernel/bpf/bpf_lsm.c2
-rw-r--r--kernel/bpf/helpers.c12
-rw-r--r--kernel/bpf/verifier.c58
4 files changed, 44 insertions, 29 deletions
diff --git a/kernel/bpf/Kconfig b/kernel/bpf/Kconfig
index 26b591e23f16..bd04f4a44c01 100644
--- a/kernel/bpf/Kconfig
+++ b/kernel/bpf/Kconfig
@@ -37,6 +37,7 @@ config BPF_SYSCALL
config BPF_JIT
bool "Enable BPF Just In Time compiler"
+ depends on BPF
depends on HAVE_CBPF_JIT || HAVE_EBPF_JIT
depends on MODULES
help
diff --git a/kernel/bpf/bpf_lsm.c b/kernel/bpf/bpf_lsm.c
index 5efb2b24012c..da471bf01b97 100644
--- a/kernel/bpf/bpf_lsm.c
+++ b/kernel/bpf/bpf_lsm.c
@@ -107,10 +107,12 @@ bpf_lsm_func_proto(enum bpf_func_id func_id, const struct bpf_prog *prog)
return &bpf_inode_storage_get_proto;
case BPF_FUNC_inode_storage_delete:
return &bpf_inode_storage_delete_proto;
+#ifdef CONFIG_NET
case BPF_FUNC_sk_storage_get:
return &bpf_sk_storage_get_proto;
case BPF_FUNC_sk_storage_delete:
return &bpf_sk_storage_delete_proto;
+#endif /* CONFIG_NET */
case BPF_FUNC_spin_lock:
return &bpf_spin_lock_proto;
case BPF_FUNC_spin_unlock:
diff --git a/kernel/bpf/helpers.c b/kernel/bpf/helpers.c
index ef658a9ea5c9..73443498d88f 100644
--- a/kernel/bpf/helpers.c
+++ b/kernel/bpf/helpers.c
@@ -692,13 +692,15 @@ static int bpf_trace_copy_string(char *buf, void *unsafe_ptr, char fmt_ptype,
return -EINVAL;
}
-/* Per-cpu temp buffers which can be used by printf-like helpers for %s or %p
+/* Per-cpu temp buffers used by printf-like helpers to store the bprintf binary
+ * arguments representation.
*/
-#define MAX_PRINTF_BUF_LEN 512
+#define MAX_BPRINTF_BUF_LEN 512
/* Support executing three nested bprintf helper calls on a given CPU */
+#define MAX_BPRINTF_NEST_LEVEL 3
struct bpf_bprintf_buffers {
- char tmp_bufs[3][MAX_PRINTF_BUF_LEN];
+ char tmp_bufs[MAX_BPRINTF_NEST_LEVEL][MAX_BPRINTF_BUF_LEN];
};
static DEFINE_PER_CPU(struct bpf_bprintf_buffers, bpf_bprintf_bufs);
static DEFINE_PER_CPU(int, bpf_bprintf_nest_level);
@@ -710,7 +712,7 @@ static int try_get_fmt_tmp_buf(char **tmp_buf)
preempt_disable();
nest_level = this_cpu_inc_return(bpf_bprintf_nest_level);
- if (WARN_ON_ONCE(nest_level > ARRAY_SIZE(bufs->tmp_bufs))) {
+ if (WARN_ON_ONCE(nest_level > MAX_BPRINTF_NEST_LEVEL)) {
this_cpu_dec(bpf_bprintf_nest_level);
preempt_enable();
return -EBUSY;
@@ -761,7 +763,7 @@ int bpf_bprintf_prepare(char *fmt, u32 fmt_size, const u64 *raw_args,
if (num_args && try_get_fmt_tmp_buf(&tmp_buf))
return -EBUSY;
- tmp_buf_end = tmp_buf + MAX_PRINTF_BUF_LEN;
+ tmp_buf_end = tmp_buf + MAX_BPRINTF_BUF_LEN;
*bin_args = (u32 *)tmp_buf;
}
diff --git a/kernel/bpf/verifier.c b/kernel/bpf/verifier.c
index c58598ef4b5b..94ba5163d4c5 100644
--- a/kernel/bpf/verifier.c
+++ b/kernel/bpf/verifier.c
@@ -6409,18 +6409,10 @@ enum {
};
static int retrieve_ptr_limit(const struct bpf_reg_state *ptr_reg,
- const struct bpf_reg_state *off_reg,
- u32 *alu_limit, u8 opcode)
+ u32 *alu_limit, bool mask_to_left)
{
- bool off_is_neg = off_reg->smin_value < 0;
- bool mask_to_left = (opcode == BPF_ADD && off_is_neg) ||
- (opcode == BPF_SUB && !off_is_neg);
u32 max = 0, ptr_limit = 0;
- if (!tnum_is_const(off_reg->var_off) &&
- (off_reg->smin_value < 0) != (off_reg->smax_value < 0))
- return REASON_BOUNDS;
-
switch (ptr_reg->type) {
case PTR_TO_STACK:
/* Offset 0 is out-of-bounds, but acceptable start for the
@@ -6486,15 +6478,20 @@ static bool sanitize_needed(u8 opcode)
return opcode == BPF_ADD || opcode == BPF_SUB;
}
+struct bpf_sanitize_info {
+ struct bpf_insn_aux_data aux;
+ bool mask_to_left;
+};
+
static int sanitize_ptr_alu(struct bpf_verifier_env *env,
struct bpf_insn *insn,
const struct bpf_reg_state *ptr_reg,
const struct bpf_reg_state *off_reg,
struct bpf_reg_state *dst_reg,
- struct bpf_insn_aux_data *tmp_aux,
+ struct bpf_sanitize_info *info,
const bool commit_window)
{
- struct bpf_insn_aux_data *aux = commit_window ? cur_aux(env) : tmp_aux;
+ struct bpf_insn_aux_data *aux = commit_window ? cur_aux(env) : &info->aux;
struct bpf_verifier_state *vstate = env->cur_state;
bool off_is_imm = tnum_is_const(off_reg->var_off);
bool off_is_neg = off_reg->smin_value < 0;
@@ -6515,7 +6512,16 @@ static int sanitize_ptr_alu(struct bpf_verifier_env *env,
if (vstate->speculative)
goto do_sim;
- err = retrieve_ptr_limit(ptr_reg, off_reg, &alu_limit, opcode);
+ if (!commit_window) {
+ if (!tnum_is_const(off_reg->var_off) &&
+ (off_reg->smin_value < 0) != (off_reg->smax_value < 0))
+ return REASON_BOUNDS;
+
+ info->mask_to_left = (opcode == BPF_ADD && off_is_neg) ||
+ (opcode == BPF_SUB && !off_is_neg);
+ }
+
+ err = retrieve_ptr_limit(ptr_reg, &alu_limit, info->mask_to_left);
if (err < 0)
return err;
@@ -6523,8 +6529,8 @@ static int sanitize_ptr_alu(struct bpf_verifier_env *env,
/* In commit phase we narrow the masking window based on
* the observed pointer move after the simulated operation.
*/
- alu_state = tmp_aux->alu_state;
- alu_limit = abs(tmp_aux->alu_limit - alu_limit);
+ alu_state = info->aux.alu_state;
+ alu_limit = abs(info->aux.alu_limit - alu_limit);
} else {
alu_state = off_is_neg ? BPF_ALU_NEG_VALUE : 0;
alu_state |= off_is_imm ? BPF_ALU_IMMEDIATE : 0;
@@ -6539,8 +6545,12 @@ do_sim:
/* If we're in commit phase, we're done here given we already
* pushed the truncated dst_reg into the speculative verification
* stack.
+ *
+ * Also, when register is a known constant, we rewrite register-based
+ * operation to immediate-based, and thus do not need masking (and as
+ * a consequence, do not need to simulate the zero-truncation either).
*/
- if (commit_window)
+ if (commit_window || off_is_imm)
return 0;
/* Simulate and find potential out-of-bounds access under
@@ -6685,7 +6695,7 @@ static int adjust_ptr_min_max_vals(struct bpf_verifier_env *env,
smin_ptr = ptr_reg->smin_value, smax_ptr = ptr_reg->smax_value;
u64 umin_val = off_reg->umin_value, umax_val = off_reg->umax_value,
umin_ptr = ptr_reg->umin_value, umax_ptr = ptr_reg->umax_value;
- struct bpf_insn_aux_data tmp_aux = {};
+ struct bpf_sanitize_info info = {};
u8 opcode = BPF_OP(insn->code);
u32 dst = insn->dst_reg;
int ret;
@@ -6754,7 +6764,7 @@ static int adjust_ptr_min_max_vals(struct bpf_verifier_env *env,
if (sanitize_needed(opcode)) {
ret = sanitize_ptr_alu(env, insn, ptr_reg, off_reg, dst_reg,
- &tmp_aux, false);
+ &info, false);
if (ret < 0)
return sanitize_err(env, insn, ret, off_reg, dst_reg);
}
@@ -6895,7 +6905,7 @@ static int adjust_ptr_min_max_vals(struct bpf_verifier_env *env,
return -EACCES;
if (sanitize_needed(opcode)) {
ret = sanitize_ptr_alu(env, insn, dst_reg, off_reg, dst_reg,
- &tmp_aux, true);
+ &info, true);
if (ret < 0)
return sanitize_err(env, insn, ret, off_reg, dst_reg);
}
@@ -13368,12 +13378,6 @@ int bpf_check(struct bpf_prog **prog, union bpf_attr *attr,
if (is_priv)
env->test_state_freq = attr->prog_flags & BPF_F_TEST_STATE_FREQ;
- if (bpf_prog_is_dev_bound(env->prog->aux)) {
- ret = bpf_prog_offload_verifier_prep(env->prog);
- if (ret)
- goto skip_full_check;
- }
-
env->explored_states = kvcalloc(state_htab_size(env),
sizeof(struct bpf_verifier_state_list *),
GFP_USER);
@@ -13401,6 +13405,12 @@ int bpf_check(struct bpf_prog **prog, union bpf_attr *attr,
if (ret < 0)
goto skip_full_check;
+ if (bpf_prog_is_dev_bound(env->prog->aux)) {
+ ret = bpf_prog_offload_verifier_prep(env->prog);
+ if (ret)
+ goto skip_full_check;
+ }
+
ret = check_cfg(env);
if (ret < 0)
goto skip_full_check;
generated by cgit v1.2.3 (git 2.39.1) at 2024-10-13 07:18:29 +0000