diff options
| author | Yonghong Song <yhs@fb.com> | 2022-11-23 21:32:11 -0800 |
|---|---|---|
| committer | Alexei Starovoitov <ast@kernel.org> | 2022-11-24 12:27:13 -0800 |
| commit | 01685c5bddaa6df3d662c8afed5e5289fcc68e5a (patch) | |
| tree | 449b395cbda9dc78cb39ae8cd1bfe15ee0e1aa16 /kernel | |
| parent | 5a0f663f0189cf9e031e444f97c029717a99548d (diff) | |
| download | linux-01685c5bddaa6df3d662c8afed5e5289fcc68e5a.tar.bz2 | |
bpf: Introduce might_sleep field in bpf_func_proto
Introduce bpf_func_proto->might_sleep to indicate a particular helper
might sleep. This will make later check whether a helper might be
sleepable or not easier.
Acked-by: Martin KaFai Lau <martin.lau@kernel.org>
Signed-off-by: Yonghong Song <yhs@fb.com>
Link: https://lore.kernel.org/r/20221124053211.2373553-1-yhs@fb.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Diffstat (limited to 'kernel')
| -rw-r--r-- | kernel/bpf/bpf_lsm.c | 6 | ||||
| -rw-r--r-- | kernel/bpf/helpers.c | 2 | ||||
| -rw-r--r-- | kernel/bpf/verifier.c | 5 | ||||
| -rw-r--r-- | kernel/trace/bpf_trace.c | 4 |
4 files changed, 13 insertions, 4 deletions
diff --git a/kernel/bpf/bpf_lsm.c b/kernel/bpf/bpf_lsm.c index d6c9b3705f24..ae0267f150b5 100644 --- a/kernel/bpf/bpf_lsm.c +++ b/kernel/bpf/bpf_lsm.c @@ -151,6 +151,7 @@ BTF_ID_LIST_SINGLE(bpf_ima_inode_hash_btf_ids, struct, inode) static const struct bpf_func_proto bpf_ima_inode_hash_proto = { .func = bpf_ima_inode_hash, .gpl_only = false, + .might_sleep = true, .ret_type = RET_INTEGER, .arg1_type = ARG_PTR_TO_BTF_ID, .arg1_btf_id = &bpf_ima_inode_hash_btf_ids[0], @@ -169,6 +170,7 @@ BTF_ID_LIST_SINGLE(bpf_ima_file_hash_btf_ids, struct, file) static const struct bpf_func_proto bpf_ima_file_hash_proto = { .func = bpf_ima_file_hash, .gpl_only = false, + .might_sleep = true, .ret_type = RET_INTEGER, .arg1_type = ARG_PTR_TO_BTF_ID, .arg1_btf_id = &bpf_ima_file_hash_btf_ids[0], @@ -221,9 +223,9 @@ bpf_lsm_func_proto(enum bpf_func_id func_id, const struct bpf_prog *prog) case BPF_FUNC_bprm_opts_set: return &bpf_bprm_opts_set_proto; case BPF_FUNC_ima_inode_hash: - return prog->aux->sleepable ? &bpf_ima_inode_hash_proto : NULL; + return &bpf_ima_inode_hash_proto; case BPF_FUNC_ima_file_hash: - return prog->aux->sleepable ? &bpf_ima_file_hash_proto : NULL; + return &bpf_ima_file_hash_proto; case BPF_FUNC_get_attach_cookie: return bpf_prog_has_trampoline(prog) ? &bpf_get_attach_cookie_proto : NULL; #ifdef CONFIG_NET diff --git a/kernel/bpf/helpers.c b/kernel/bpf/helpers.c index 2299bb0d89e5..9296b654dbd7 100644 --- a/kernel/bpf/helpers.c +++ b/kernel/bpf/helpers.c @@ -661,6 +661,7 @@ BPF_CALL_3(bpf_copy_from_user, void *, dst, u32, size, const struct bpf_func_proto bpf_copy_from_user_proto = { .func = bpf_copy_from_user, .gpl_only = false, + .might_sleep = true, .ret_type = RET_INTEGER, .arg1_type = ARG_PTR_TO_UNINIT_MEM, .arg2_type = ARG_CONST_SIZE_OR_ZERO, @@ -691,6 +692,7 @@ BPF_CALL_5(bpf_copy_from_user_task, void *, dst, u32, size, const struct bpf_func_proto bpf_copy_from_user_task_proto = { .func = bpf_copy_from_user_task, .gpl_only = true, + .might_sleep = true, .ret_type = RET_INTEGER, .arg1_type = ARG_PTR_TO_UNINIT_MEM, .arg2_type = ARG_CONST_SIZE_OR_ZERO, diff --git a/kernel/bpf/verifier.c b/kernel/bpf/verifier.c index 9528a066cfa5..068cc885903c 100644 --- a/kernel/bpf/verifier.c +++ b/kernel/bpf/verifier.c @@ -7516,6 +7516,11 @@ static int check_helper_call(struct bpf_verifier_env *env, struct bpf_insn *insn return -EINVAL; } + if (!env->prog->aux->sleepable && fn->might_sleep) { + verbose(env, "helper call might sleep in a non-sleepable prog\n"); + return -EINVAL; + } + /* With LD_ABS/IND some JITs save/restore skb from r1. */ changes_data = bpf_helper_changes_pkt_data(fn->func); if (changes_data && fn->arg1_type != ARG_PTR_TO_CTX) { diff --git a/kernel/trace/bpf_trace.c b/kernel/trace/bpf_trace.c index 5b9008bc597b..3bbd3f0c810c 100644 --- a/kernel/trace/bpf_trace.c +++ b/kernel/trace/bpf_trace.c @@ -1485,9 +1485,9 @@ bpf_tracing_func_proto(enum bpf_func_id func_id, const struct bpf_prog *prog) case BPF_FUNC_get_task_stack: return &bpf_get_task_stack_proto; case BPF_FUNC_copy_from_user: - return prog->aux->sleepable ? &bpf_copy_from_user_proto : NULL; + return &bpf_copy_from_user_proto; case BPF_FUNC_copy_from_user_task: - return prog->aux->sleepable ? &bpf_copy_from_user_task_proto : NULL; + return &bpf_copy_from_user_task_proto; case BPF_FUNC_snprintf_btf: return &bpf_snprintf_btf_proto; case BPF_FUNC_per_cpu_ptr: |