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-rw-r--r--kernel/bpf/btf.c7
-rw-r--r--kernel/bpf/trampoline.c8
-rw-r--r--kernel/bpf/verifier.c77
-rw-r--r--kernel/trace/bpf_trace.c55
4 files changed, 137 insertions, 10 deletions
diff --git a/kernel/bpf/btf.c b/kernel/bpf/btf.c
index 65231045a5294..a17de71abd2e6 100644
--- a/kernel/bpf/btf.c
+++ b/kernel/bpf/btf.c
@@ -4826,7 +4826,7 @@ struct btf *bpf_prog_get_target_btf(const struct bpf_prog *prog)
return prog->aux->attach_btf;
}
-static bool is_string_ptr(struct btf *btf, const struct btf_type *t)
+static bool is_int_ptr(struct btf *btf, const struct btf_type *t)
{
/* t comes in already as a pointer */
t = btf_type_by_id(btf, t->type);
@@ -4835,8 +4835,7 @@ static bool is_string_ptr(struct btf *btf, const struct btf_type *t)
if (BTF_INFO_KIND(t->info) == BTF_KIND_CONST)
t = btf_type_by_id(btf, t->type);
- /* char, signed char, unsigned char */
- return btf_type_is_int(t) && t->size == 1;
+ return btf_type_is_int(t);
}
bool btf_ctx_access(int off, int size, enum bpf_access_type type,
@@ -4957,7 +4956,7 @@ bool btf_ctx_access(int off, int size, enum bpf_access_type type,
*/
return true;
- if (is_string_ptr(btf, t))
+ if (is_int_ptr(btf, t))
return true;
/* this is a pointer to another type */
diff --git a/kernel/bpf/trampoline.c b/kernel/bpf/trampoline.c
index e98de5e73ba59..4b6974a195c13 100644
--- a/kernel/bpf/trampoline.c
+++ b/kernel/bpf/trampoline.c
@@ -27,6 +27,14 @@ static struct hlist_head trampoline_table[TRAMPOLINE_TABLE_SIZE];
/* serializes access to trampoline_table */
static DEFINE_MUTEX(trampoline_mutex);
+bool bpf_prog_has_trampoline(const struct bpf_prog *prog)
+{
+ enum bpf_attach_type eatype = prog->expected_attach_type;
+
+ return eatype == BPF_TRACE_FENTRY || eatype == BPF_TRACE_FEXIT ||
+ eatype == BPF_MODIFY_RETURN;
+}
+
void *bpf_jit_alloc_exec_page(void)
{
void *image;
diff --git a/kernel/bpf/verifier.c b/kernel/bpf/verifier.c
index b39de3ae50f57..d74e8a99412e7 100644
--- a/kernel/bpf/verifier.c
+++ b/kernel/bpf/verifier.c
@@ -6395,13 +6395,11 @@ static int check_bpf_snprintf_call(struct bpf_verifier_env *env,
static int check_get_func_ip(struct bpf_verifier_env *env)
{
- enum bpf_attach_type eatype = env->prog->expected_attach_type;
enum bpf_prog_type type = resolve_prog_type(env->prog);
int func_id = BPF_FUNC_get_func_ip;
if (type == BPF_PROG_TYPE_TRACING) {
- if (eatype != BPF_TRACE_FENTRY && eatype != BPF_TRACE_FEXIT &&
- eatype != BPF_MODIFY_RETURN) {
+ if (!bpf_prog_has_trampoline(env->prog)) {
verbose(env, "func %s#%d supported only for fentry/fexit/fmod_ret programs\n",
func_id_name(func_id), func_id);
return -ENOTSUPP;
@@ -12997,6 +12995,7 @@ static int fixup_kfunc_call(struct bpf_verifier_env *env,
static int do_misc_fixups(struct bpf_verifier_env *env)
{
struct bpf_prog *prog = env->prog;
+ enum bpf_attach_type eatype = prog->expected_attach_type;
bool expect_blinding = bpf_jit_blinding_enabled(prog);
enum bpf_prog_type prog_type = resolve_prog_type(prog);
struct bpf_insn *insn = prog->insnsi;
@@ -13367,11 +13366,79 @@ patch_map_ops_generic:
continue;
}
+ /* Implement bpf_get_func_arg inline. */
+ if (prog_type == BPF_PROG_TYPE_TRACING &&
+ insn->imm == BPF_FUNC_get_func_arg) {
+ /* Load nr_args from ctx - 8 */
+ insn_buf[0] = BPF_LDX_MEM(BPF_DW, BPF_REG_0, BPF_REG_1, -8);
+ insn_buf[1] = BPF_JMP32_REG(BPF_JGE, BPF_REG_2, BPF_REG_0, 6);
+ insn_buf[2] = BPF_ALU64_IMM(BPF_LSH, BPF_REG_2, 3);
+ insn_buf[3] = BPF_ALU64_REG(BPF_ADD, BPF_REG_2, BPF_REG_1);
+ insn_buf[4] = BPF_LDX_MEM(BPF_DW, BPF_REG_0, BPF_REG_2, 0);
+ insn_buf[5] = BPF_STX_MEM(BPF_DW, BPF_REG_3, BPF_REG_0, 0);
+ insn_buf[6] = BPF_MOV64_IMM(BPF_REG_0, 0);
+ insn_buf[7] = BPF_JMP_A(1);
+ insn_buf[8] = BPF_MOV64_IMM(BPF_REG_0, -EINVAL);
+ cnt = 9;
+
+ new_prog = bpf_patch_insn_data(env, i + delta, insn_buf, cnt);
+ if (!new_prog)
+ return -ENOMEM;
+
+ delta += cnt - 1;
+ env->prog = prog = new_prog;
+ insn = new_prog->insnsi + i + delta;
+ continue;
+ }
+
+ /* Implement bpf_get_func_ret inline. */
+ if (prog_type == BPF_PROG_TYPE_TRACING &&
+ insn->imm == BPF_FUNC_get_func_ret) {
+ if (eatype == BPF_TRACE_FEXIT ||
+ eatype == BPF_MODIFY_RETURN) {
+ /* Load nr_args from ctx - 8 */
+ insn_buf[0] = BPF_LDX_MEM(BPF_DW, BPF_REG_0, BPF_REG_1, -8);
+ insn_buf[1] = BPF_ALU64_IMM(BPF_LSH, BPF_REG_0, 3);
+ insn_buf[2] = BPF_ALU64_REG(BPF_ADD, BPF_REG_0, BPF_REG_1);
+ insn_buf[3] = BPF_LDX_MEM(BPF_DW, BPF_REG_3, BPF_REG_0, 0);
+ insn_buf[4] = BPF_STX_MEM(BPF_DW, BPF_REG_2, BPF_REG_3, 0);
+ insn_buf[5] = BPF_MOV64_IMM(BPF_REG_0, 0);
+ cnt = 6;
+ } else {
+ insn_buf[0] = BPF_MOV64_IMM(BPF_REG_0, -EOPNOTSUPP);
+ cnt = 1;
+ }
+
+ new_prog = bpf_patch_insn_data(env, i + delta, insn_buf, cnt);
+ if (!new_prog)
+ return -ENOMEM;
+
+ delta += cnt - 1;
+ env->prog = prog = new_prog;
+ insn = new_prog->insnsi + i + delta;
+ continue;
+ }
+
+ /* Implement get_func_arg_cnt inline. */
+ if (prog_type == BPF_PROG_TYPE_TRACING &&
+ insn->imm == BPF_FUNC_get_func_arg_cnt) {
+ /* Load nr_args from ctx - 8 */
+ insn_buf[0] = BPF_LDX_MEM(BPF_DW, BPF_REG_0, BPF_REG_1, -8);
+
+ new_prog = bpf_patch_insn_data(env, i + delta, insn_buf, 1);
+ if (!new_prog)
+ return -ENOMEM;
+
+ env->prog = prog = new_prog;
+ insn = new_prog->insnsi + i + delta;
+ continue;
+ }
+
/* Implement bpf_get_func_ip inline. */
if (prog_type == BPF_PROG_TYPE_TRACING &&
insn->imm == BPF_FUNC_get_func_ip) {
- /* Load IP address from ctx - 8 */
- insn_buf[0] = BPF_LDX_MEM(BPF_DW, BPF_REG_0, BPF_REG_1, -8);
+ /* Load IP address from ctx - 16 */
+ insn_buf[0] = BPF_LDX_MEM(BPF_DW, BPF_REG_0, BPF_REG_1, -16);
new_prog = bpf_patch_insn_data(env, i + delta, insn_buf, 1);
if (!new_prog)
diff --git a/kernel/trace/bpf_trace.c b/kernel/trace/bpf_trace.c
index 623dd06844290..cea2ca6df949b 100644
--- a/kernel/trace/bpf_trace.c
+++ b/kernel/trace/bpf_trace.c
@@ -1012,7 +1012,7 @@ const struct bpf_func_proto bpf_snprintf_btf_proto = {
BPF_CALL_1(bpf_get_func_ip_tracing, void *, ctx)
{
/* This helper call is inlined by verifier. */
- return ((u64 *)ctx)[-1];
+ return ((u64 *)ctx)[-2];
}
static const struct bpf_func_proto bpf_get_func_ip_proto_tracing = {
@@ -1091,6 +1091,53 @@ static const struct bpf_func_proto bpf_get_branch_snapshot_proto = {
.arg2_type = ARG_CONST_SIZE_OR_ZERO,
};
+BPF_CALL_3(get_func_arg, void *, ctx, u32, n, u64 *, value)
+{
+ /* This helper call is inlined by verifier. */
+ u64 nr_args = ((u64 *)ctx)[-1];
+
+ if ((u64) n >= nr_args)
+ return -EINVAL;
+ *value = ((u64 *)ctx)[n];
+ return 0;
+}
+
+static const struct bpf_func_proto bpf_get_func_arg_proto = {
+ .func = get_func_arg,
+ .ret_type = RET_INTEGER,
+ .arg1_type = ARG_PTR_TO_CTX,
+ .arg2_type = ARG_ANYTHING,
+ .arg3_type = ARG_PTR_TO_LONG,
+};
+
+BPF_CALL_2(get_func_ret, void *, ctx, u64 *, value)
+{
+ /* This helper call is inlined by verifier. */
+ u64 nr_args = ((u64 *)ctx)[-1];
+
+ *value = ((u64 *)ctx)[nr_args];
+ return 0;
+}
+
+static const struct bpf_func_proto bpf_get_func_ret_proto = {
+ .func = get_func_ret,
+ .ret_type = RET_INTEGER,
+ .arg1_type = ARG_PTR_TO_CTX,
+ .arg2_type = ARG_PTR_TO_LONG,
+};
+
+BPF_CALL_1(get_func_arg_cnt, void *, ctx)
+{
+ /* This helper call is inlined by verifier. */
+ return ((u64 *)ctx)[-1];
+}
+
+static const struct bpf_func_proto bpf_get_func_arg_cnt_proto = {
+ .func = get_func_arg_cnt,
+ .ret_type = RET_INTEGER,
+ .arg1_type = ARG_PTR_TO_CTX,
+};
+
static const struct bpf_func_proto *
bpf_tracing_func_proto(enum bpf_func_id func_id, const struct bpf_prog *prog)
{
@@ -1629,6 +1676,12 @@ tracing_prog_func_proto(enum bpf_func_id func_id, const struct bpf_prog *prog)
NULL;
case BPF_FUNC_d_path:
return &bpf_d_path_proto;
+ case BPF_FUNC_get_func_arg:
+ return bpf_prog_has_trampoline(prog) ? &bpf_get_func_arg_proto : NULL;
+ case BPF_FUNC_get_func_ret:
+ return bpf_prog_has_trampoline(prog) ? &bpf_get_func_ret_proto : NULL;
+ case BPF_FUNC_get_func_arg_cnt:
+ return bpf_prog_has_trampoline(prog) ? &bpf_get_func_arg_cnt_proto : NULL;
default:
fn = raw_tp_prog_func_proto(func_id, prog);
if (!fn && prog->expected_attach_type == BPF_TRACE_ITER)
generated by cgit v1.2.3 (git 2.39.1) at 2025-08-09 01:49:49 +0000