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path: root/arch/x86/net/bpf_jit_comp.c
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Diffstat (limited to 'arch/x86/net/bpf_jit_comp.c')
-rw-r--r--arch/x86/net/bpf_jit_comp.c98
1 files changed, 67 insertions, 31 deletions
diff --git a/arch/x86/net/bpf_jit_comp.c b/arch/x86/net/bpf_jit_comp.c
index c1f6c1c51d99..5b6230779cf3 100644
--- a/arch/x86/net/bpf_jit_comp.c
+++ b/arch/x86/net/bpf_jit_comp.c
@@ -662,7 +662,7 @@ static void emit_mov_imm64(u8 **pprog, u32 dst_reg,
*/
emit_mov_imm32(&prog, false, dst_reg, imm32_lo);
} else {
- /* movabsq %rax, imm64 */
+ /* movabsq rax, imm64 */
EMIT2(add_1mod(0x48, dst_reg), add_1reg(0xB8, dst_reg));
EMIT(imm32_lo, 4);
EMIT(imm32_hi, 4);
@@ -1751,34 +1751,60 @@ emit_jmp:
static void save_regs(const struct btf_func_model *m, u8 **prog, int nr_args,
int stack_size)
{
- int i;
+ int i, j, arg_size, nr_regs;
/* Store function arguments to stack.
* For a function that accepts two pointers the sequence will be:
* mov QWORD PTR [rbp-0x10],rdi
* mov QWORD PTR [rbp-0x8],rsi
*/
- for (i = 0; i < min(nr_args, 6); i++)
- emit_stx(prog, bytes_to_bpf_size(m->arg_size[i]),
- BPF_REG_FP,
- i == 5 ? X86_REG_R9 : BPF_REG_1 + i,
- -(stack_size - i * 8));
+ for (i = 0, j = 0; i < min(nr_args, 6); i++) {
+ if (m->arg_flags[i] & BTF_FMODEL_STRUCT_ARG) {
+ nr_regs = (m->arg_size[i] + 7) / 8;
+ arg_size = 8;
+ } else {
+ nr_regs = 1;
+ arg_size = m->arg_size[i];
+ }
+
+ while (nr_regs) {
+ emit_stx(prog, bytes_to_bpf_size(arg_size),
+ BPF_REG_FP,
+ j == 5 ? X86_REG_R9 : BPF_REG_1 + j,
+ -(stack_size - j * 8));
+ nr_regs--;
+ j++;
+ }
+ }
}
static void restore_regs(const struct btf_func_model *m, u8 **prog, int nr_args,
int stack_size)
{
- int i;
+ int i, j, arg_size, nr_regs;
/* Restore function arguments from stack.
* For a function that accepts two pointers the sequence will be:
* EMIT4(0x48, 0x8B, 0x7D, 0xF0); mov rdi,QWORD PTR [rbp-0x10]
* EMIT4(0x48, 0x8B, 0x75, 0xF8); mov rsi,QWORD PTR [rbp-0x8]
*/
- for (i = 0; i < min(nr_args, 6); i++)
- emit_ldx(prog, bytes_to_bpf_size(m->arg_size[i]),
- i == 5 ? X86_REG_R9 : BPF_REG_1 + i,
- BPF_REG_FP,
- -(stack_size - i * 8));
+ for (i = 0, j = 0; i < min(nr_args, 6); i++) {
+ if (m->arg_flags[i] & BTF_FMODEL_STRUCT_ARG) {
+ nr_regs = (m->arg_size[i] + 7) / 8;
+ arg_size = 8;
+ } else {
+ nr_regs = 1;
+ arg_size = m->arg_size[i];
+ }
+
+ while (nr_regs) {
+ emit_ldx(prog, bytes_to_bpf_size(arg_size),
+ j == 5 ? X86_REG_R9 : BPF_REG_1 + j,
+ BPF_REG_FP,
+ -(stack_size - j * 8));
+ nr_regs--;
+ j++;
+ }
+ }
}
static int invoke_bpf_prog(const struct btf_func_model *m, u8 **pprog,
@@ -1810,6 +1836,9 @@ static int invoke_bpf_prog(const struct btf_func_model *m, u8 **pprog,
if (p->aux->sleepable) {
enter = __bpf_prog_enter_sleepable;
exit = __bpf_prog_exit_sleepable;
+ } else if (p->type == BPF_PROG_TYPE_STRUCT_OPS) {
+ enter = __bpf_prog_enter_struct_ops;
+ exit = __bpf_prog_exit_struct_ops;
} else if (p->expected_attach_type == BPF_LSM_CGROUP) {
enter = __bpf_prog_enter_lsm_cgroup;
exit = __bpf_prog_exit_lsm_cgroup;
@@ -2013,13 +2042,14 @@ static int invoke_bpf_mod_ret(const struct btf_func_model *m, u8 **pprog,
int arch_prepare_bpf_trampoline(struct bpf_tramp_image *im, void *image, void *image_end,
const struct btf_func_model *m, u32 flags,
struct bpf_tramp_links *tlinks,
- void *orig_call)
+ void *func_addr)
{
- int ret, i, nr_args = m->nr_args;
+ int ret, i, nr_args = m->nr_args, extra_nregs = 0;
int regs_off, ip_off, args_off, stack_size = nr_args * 8, run_ctx_off;
struct bpf_tramp_links *fentry = &tlinks[BPF_TRAMP_FENTRY];
struct bpf_tramp_links *fexit = &tlinks[BPF_TRAMP_FEXIT];
struct bpf_tramp_links *fmod_ret = &tlinks[BPF_TRAMP_MODIFY_RETURN];
+ void *orig_call = func_addr;
u8 **branches = NULL;
u8 *prog;
bool save_ret;
@@ -2028,6 +2058,14 @@ int arch_prepare_bpf_trampoline(struct bpf_tramp_image *im, void *image, void *i
if (nr_args > 6)
return -ENOTSUPP;
+ for (i = 0; i < MAX_BPF_FUNC_ARGS; i++) {
+ if (m->arg_flags[i] & BTF_FMODEL_STRUCT_ARG)
+ extra_nregs += (m->arg_size[i] + 7) / 8 - 1;
+ }
+ if (nr_args + extra_nregs > 6)
+ return -ENOTSUPP;
+ stack_size += extra_nregs * 8;
+
/* Generated trampoline stack layout:
*
* RBP + 8 [ return address ]
@@ -2040,7 +2078,7 @@ int arch_prepare_bpf_trampoline(struct bpf_tramp_image *im, void *image, void *i
* [ ... ]
* RBP - regs_off [ reg_arg1 ] program's ctx pointer
*
- * RBP - args_off [ args count ] always
+ * RBP - args_off [ arg regs count ] always
*
* RBP - ip_off [ traced function ] BPF_TRAMP_F_IP_ARG flag
*
@@ -2083,21 +2121,19 @@ int arch_prepare_bpf_trampoline(struct bpf_tramp_image *im, void *image, void *i
EMIT4(0x48, 0x83, 0xEC, stack_size); /* sub rsp, stack_size */
EMIT1(0x53); /* push rbx */
- /* Store number of arguments of the traced function:
- * mov rax, nr_args
+ /* Store number of argument registers of the traced function:
+ * mov rax, nr_args + extra_nregs
* mov QWORD PTR [rbp - args_off], rax
*/
- emit_mov_imm64(&prog, BPF_REG_0, 0, (u32) nr_args);
+ emit_mov_imm64(&prog, BPF_REG_0, 0, (u32) nr_args + extra_nregs);
emit_stx(&prog, BPF_DW, BPF_REG_FP, BPF_REG_0, -args_off);
if (flags & BPF_TRAMP_F_IP_ARG) {
/* Store IP address of the traced function:
- * mov rax, QWORD PTR [rbp + 8]
- * sub rax, X86_PATCH_SIZE
+ * movabsq rax, func_addr
* mov QWORD PTR [rbp - ip_off], rax
*/
- emit_ldx(&prog, BPF_DW, BPF_REG_0, BPF_REG_FP, 8);
- EMIT4(0x48, 0x83, 0xe8, X86_PATCH_SIZE);
+ emit_mov_imm64(&prog, BPF_REG_0, (long) func_addr >> 32, (u32) (long) func_addr);
emit_stx(&prog, BPF_DW, BPF_REG_FP, BPF_REG_0, -ip_off);
}
@@ -2209,7 +2245,7 @@ cleanup:
return ret;
}
-static int emit_bpf_dispatcher(u8 **pprog, int a, int b, s64 *progs)
+static int emit_bpf_dispatcher(u8 **pprog, int a, int b, s64 *progs, u8 *image, u8 *buf)
{
u8 *jg_reloc, *prog = *pprog;
int pivot, err, jg_bytes = 1;
@@ -2225,12 +2261,12 @@ static int emit_bpf_dispatcher(u8 **pprog, int a, int b, s64 *progs)
EMIT2_off32(0x81, add_1reg(0xF8, BPF_REG_3),
progs[a]);
err = emit_cond_near_jump(&prog, /* je func */
- (void *)progs[a], prog,
+ (void *)progs[a], image + (prog - buf),
X86_JE);
if (err)
return err;
- emit_indirect_jump(&prog, 2 /* rdx */, prog);
+ emit_indirect_jump(&prog, 2 /* rdx */, image + (prog - buf));
*pprog = prog;
return 0;
@@ -2255,7 +2291,7 @@ static int emit_bpf_dispatcher(u8 **pprog, int a, int b, s64 *progs)
jg_reloc = prog;
err = emit_bpf_dispatcher(&prog, a, a + pivot, /* emit lower_part */
- progs);
+ progs, image, buf);
if (err)
return err;
@@ -2269,7 +2305,7 @@ static int emit_bpf_dispatcher(u8 **pprog, int a, int b, s64 *progs)
emit_code(jg_reloc - jg_bytes, jg_offset, jg_bytes);
err = emit_bpf_dispatcher(&prog, a + pivot + 1, /* emit upper_part */
- b, progs);
+ b, progs, image, buf);
if (err)
return err;
@@ -2289,12 +2325,12 @@ static int cmp_ips(const void *a, const void *b)
return 0;
}
-int arch_prepare_bpf_dispatcher(void *image, s64 *funcs, int num_funcs)
+int arch_prepare_bpf_dispatcher(void *image, void *buf, s64 *funcs, int num_funcs)
{
- u8 *prog = image;
+ u8 *prog = buf;
sort(funcs, num_funcs, sizeof(funcs[0]), cmp_ips, NULL);
- return emit_bpf_dispatcher(&prog, 0, num_funcs - 1, funcs);
+ return emit_bpf_dispatcher(&prog, 0, num_funcs - 1, funcs, image, buf);
}
struct x64_jit_data {