From: Lorenz Bauer <lmb@cloudflare.com>
To: ast@kernel.org, yhs@fb.com, daniel@iogearbox.net, kafai@fb.com
Cc: bpf@vger.kernel.org, kernel-team@cloudflare.com,
Lorenz Bauer <lmb@cloudflare.com>
Subject: [PATCH bpf-next 06/11] bpf: make reference tracking in check_func_arg generic
Date: Fri, 4 Sep 2020 12:23:56 +0100 [thread overview]
Message-ID: <20200904112401.667645-7-lmb@cloudflare.com> (raw)
In-Reply-To: <20200904112401.667645-1-lmb@cloudflare.com>
Instead of dealing with reg->ref_obj_id individually for every arg type that
needs it, rely on the fact that ref_obj_id is zero if the register is not
reference tracked.
Signed-off-by: Lorenz Bauer <lmb@cloudflare.com>
---
kernel/bpf/verifier.c | 26 ++++++++++----------------
1 file changed, 10 insertions(+), 16 deletions(-)
diff --git a/kernel/bpf/verifier.c b/kernel/bpf/verifier.c
index 45759638e1b8..c7df4ccad8e2 100644
--- a/kernel/bpf/verifier.c
+++ b/kernel/bpf/verifier.c
@@ -3988,15 +3988,6 @@ static int check_func_arg(struct bpf_verifier_env *env, u32 arg,
/* Any sk pointer can be ARG_PTR_TO_SOCK_COMMON */
if (!type_is_sk_pointer(type))
goto err_type;
- if (reg->ref_obj_id) {
- if (meta->ref_obj_id) {
- verbose(env, "verifier internal error: more than one arg with ref_obj_id R%d %u %u\n",
- regno, reg->ref_obj_id,
- meta->ref_obj_id);
- return -EFAULT;
- }
- meta->ref_obj_id = reg->ref_obj_id;
- }
} else if (arg_type == ARG_PTR_TO_SOCKET ||
arg_type == ARG_PTR_TO_SOCKET_OR_NULL) {
expected_type = PTR_TO_SOCKET;
@@ -4047,13 +4038,6 @@ static int check_func_arg(struct bpf_verifier_env *env, u32 arg,
/* final test in check_stack_boundary() */;
else if (type != expected_type)
goto err_type;
- if (meta->ref_obj_id) {
- verbose(env, "verifier internal error: more than one arg with ref_obj_id R%d %u %u\n",
- regno, reg->ref_obj_id,
- meta->ref_obj_id);
- return -EFAULT;
- }
- meta->ref_obj_id = reg->ref_obj_id;
} else if (arg_type_is_int_ptr(arg_type)) {
expected_type = PTR_TO_STACK;
if (!type_is_pkt_pointer(type) &&
@@ -4087,6 +4071,16 @@ static int check_func_arg(struct bpf_verifier_env *env, u32 arg,
}
}
+ if (reg->ref_obj_id) {
+ if (meta->ref_obj_id) {
+ verbose(env, "verifier internal error: more than one arg with ref_obj_id R%d %u %u\n",
+ regno, reg->ref_obj_id,
+ meta->ref_obj_id);
+ return -EFAULT;
+ }
+ meta->ref_obj_id = reg->ref_obj_id;
+ }
+
if (arg_type == ARG_CONST_MAP_PTR) {
/* bpf_map_xxx(map_ptr) call: remember that map_ptr */
meta->map_ptr = reg->map_ptr;
--
2.25.1
next prev parent reply other threads:[~2020-09-04 11:29 UTC|newest]
Thread overview: 28+ messages / expand[flat|nested] mbox.gz Atom feed top
2020-09-04 11:23 [PATCH bpf-next 00/11] RFC: Make check_func_arg table driven Lorenz Bauer
2020-09-04 11:23 ` [PATCH bpf-next 01/11] btf: Fix BTF_SET_START_GLOBAL macro Lorenz Bauer
2020-09-09 4:04 ` Andrii Nakryiko
2020-09-09 9:51 ` Lorenz Bauer
2020-09-04 11:23 ` [PATCH bpf-next 02/11] btf: add a global set of valid BTF socket ids Lorenz Bauer
2020-09-09 4:12 ` Andrii Nakryiko
2020-09-04 11:23 ` [PATCH bpf-next 03/11] btf: make btf_set_contains take a const pointer Lorenz Bauer
2020-09-09 4:13 ` Andrii Nakryiko
2020-09-04 11:23 ` [PATCH bpf-next 04/11] bpf: check scalar or invalid register in check_helper_mem_access Lorenz Bauer
2020-09-09 4:22 ` Andrii Nakryiko
2020-09-09 10:02 ` Lorenz Bauer
2020-09-04 11:23 ` [PATCH bpf-next 05/11] bpf: allow specifying a set of BTF IDs for helper arguments Lorenz Bauer
2020-09-06 23:04 ` Martin KaFai Lau
2020-09-07 9:15 ` Lorenz Bauer
2020-09-09 4:47 ` Andrii Nakryiko
2020-09-09 5:56 ` Martin KaFai Lau
2020-09-09 10:06 ` Lorenz Bauer
2020-09-09 10:11 ` Lorenz Bauer
2020-09-04 11:23 ` Lorenz Bauer [this message]
2020-09-09 4:50 ` [PATCH bpf-next 06/11] bpf: make reference tracking in check_func_arg generic Andrii Nakryiko
2020-09-04 11:23 ` [PATCH bpf-next 07/11] bpf: always check access to PTR_TO_CTX regardless of arg_type Lorenz Bauer
2020-09-04 11:23 ` [PATCH bpf-next 08/11] bpf: set meta->raw_mode for pointers to memory closer to it's use Lorenz Bauer
2020-09-04 11:23 ` [PATCH bpf-next 09/11] bpf: check ARG_PTR_TO_SPINLOCK register type in check_func_arg Lorenz Bauer
2020-09-04 11:24 ` [PATCH bpf-next 10/11] bpf: hoist type checking for nullable arg types Lorenz Bauer
2020-09-09 5:07 ` Andrii Nakryiko
2020-09-04 11:24 ` [PATCH bpf-next 11/11] bpf: use a table to drive helper arg type checks Lorenz Bauer
2020-09-09 6:17 ` [PATCH bpf-next 00/11] RFC: Make check_func_arg table driven Martin KaFai Lau
2020-09-09 10:15 ` Lorenz Bauer
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