From: Leon Hwang <leon.hwang@linux.dev>
To: chenyuan_fl@163.com, martin.lau@linux.dev, ast@kernel.org,
daniel@iogearbox.net, andrii@kernel.org, eddyz87@gmail.com,
memxor@gmail.com, song@kernel.org, yonghong.song@linux.dev,
jolsa@kernel.org
Cc: bpf@vger.kernel.org, linux-kernel@vger.kernel.org,
Yuan Chen <chenyuan@kylinos.cn>
Subject: Re: [PATCH] bpf: fix btf_types_are_same for cross-BTF type comparison
Date: Tue, 7 Apr 2026 16:58:54 +0800 [thread overview]
Message-ID: <6adf726f-f51b-4a89-aadc-077a58feb311@linux.dev> (raw)
In-Reply-To: <20260407080900.551797-1-chenyuan_fl@163.com>
pls also check sashiko's review:
https://sashiko.dev/#/patchset/20260407080900.551797-1-chenyuan_fl%40163.com.
Target tree should be specified: [PATCH bpf] bpf: ...
On 7/4/26 16:09, chenyuan_fl@163.com wrote:
> From: Yuan Chen <chenyuan@kylinos.cn>
>
> When comparing types from different BTF objects (e.g., module BTF vs
> vmlinux BTF), the original btf_types_are_same() returns false because:
> - Type IDs are local to each BTF
> - Pointer comparison of btf_type_by_id results always fails
>
> This prevents kfuncs with KF_IMPLICIT_ARGS flag from modules (like
> bpf_kfunc_multi_st_ops_test_1_assoc) from properly recognizing implicit
> arguments such as 'struct bpf_prog_aux *', causing the verifier to not
> inject the aux pointer value during fixup.
Should add a selftest to verify the BUG and this fix.
Thanks,
Leon
>
> Fix by comparing actual type content (kind, size, name) when BTFs are
> different instead of comparing pointers.
>
> Signed-off-by: Yuan Chen <chenyuan@kylinos.cn>
> ---
[...]
next prev parent reply other threads:[~2026-04-07 8:59 UTC|newest]
Thread overview: 48+ messages / expand[flat|nested] mbox.gz Atom feed top
2026-04-07 8:09 chenyuan_fl
2026-04-07 8:58 ` Leon Hwang [this message]
2026-04-07 9:01 ` bot+bpf-ci
2026-04-07 11:19 ` Alan Maguire
2026-05-15 18:27 ` Ihor Solodrai
2026-06-01 6:46 ` [PATCH bpf v2 0/2] bpf: Fix kfunc implicit arg injection and add selftest chenyuan_fl
2026-06-01 6:46 ` [PATCH bpf v2 1/2] bpf: Fix kfunc implicit arg inject type detection to prevent invalid pointer deref chenyuan_fl
2026-06-01 7:42 ` bot+bpf-ci
2026-06-01 19:32 ` Eduard Zingerman
2026-06-02 8:58 ` [PATCH bpf v3 0/2] bpf: Fix kfunc implicit arg injection and add selftest chenyuan_fl
2026-06-02 8:58 ` [PATCH bpf v3 1/2] bpf: Fix kfunc implicit arg inject type detection to prevent invalid pointer deref chenyuan_fl
2026-06-02 9:44 ` bot+bpf-ci
2026-06-02 18:52 ` Ihor Solodrai
2026-06-04 9:14 ` chenyuan
2026-06-04 10:21 ` Alan Maguire
2026-06-09 0:46 ` Ihor Solodrai
2026-06-02 8:58 ` [PATCH bpf v3 2/2] selftests/bpf: Add regression test for kfunc implicit arg injection chenyuan_fl
2026-06-02 9:44 ` bot+bpf-ci
2026-06-02 9:38 ` [PATCH bpf v4 0/2] bpf: Fix kfunc implicit arg injection and add selftest chenyuan_fl
2026-06-02 9:38 ` [PATCH bpf v4 1/2] bpf: Fix kfunc implicit arg inject type detection to prevent invalid pointer deref chenyuan_fl
2026-06-02 10:42 ` bot+bpf-ci
2026-06-05 0:42 ` Eduard Zingerman
2026-06-02 9:38 ` [PATCH bpf v4 2/2] selftests/bpf: Add regression test for kfunc implicit arg injection chenyuan_fl
2026-06-02 10:27 ` bot+bpf-ci
2026-06-02 17:36 ` kernel test robot
2026-06-02 18:37 ` kernel test robot
2026-06-05 1:29 ` Eduard Zingerman
2026-06-08 14:26 ` [PATCH bpf v5 0/2] bpf: Fix kfunc implicit arg injection and add selftest chenyuan_fl
2026-06-08 14:26 ` [PATCH bpf v5 1/2] bpf: Fix kfunc implicit arg inject type detection to prevent invalid pointer deref chenyuan_fl
2026-06-08 14:52 ` bot+bpf-ci
2026-06-08 17:28 ` Eduard Zingerman
2026-06-09 0:54 ` Ihor Solodrai
2026-06-09 1:00 ` Eduard Zingerman
2026-06-09 1:18 ` Ihor Solodrai
2026-06-09 6:20 ` Eduard Zingerman
2026-06-08 14:26 ` [PATCH bpf v5 2/2] selftests/bpf: strengthen bpf_kfunc_implicit_arg to verify aux injection chenyuan_fl
2026-06-08 17:34 ` Eduard Zingerman
2026-06-09 0:59 ` Ihor Solodrai
2026-06-08 19:58 ` [PATCH bpf v5 0/2] bpf: Fix kfunc implicit arg injection and add selftest Alexei Starovoitov
2026-06-09 12:52 ` [PATCH bpf v6 " chenyuan_fl
2026-06-09 12:52 ` [PATCH bpf v6 1/2] bpf: Fix kfunc implicit arg inject type detection to prevent invalid pointer deref chenyuan_fl
2026-06-09 13:32 ` bot+bpf-ci
2026-06-09 16:39 ` Eduard Zingerman
2026-06-09 12:52 ` [PATCH bpf v6 2/2] selftests/bpf: strengthen bpf_kfunc_implicit_arg to verify aux injection chenyuan_fl
2026-06-01 17:12 ` [PATCH bpf v2 1/2] bpf: Fix kfunc implicit arg inject type detection to prevent invalid pointer deref Yonghong Song
2026-06-01 21:36 ` Eduard Zingerman
2026-06-01 6:46 ` [PATCH bpf v2 2/2] selftests/bpf: Add regression test for kfunc implicit arg injection with stale register chenyuan_fl
2026-06-01 17:17 ` Yonghong Song
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=6adf726f-f51b-4a89-aadc-077a58feb311@linux.dev \
--to=leon.hwang@linux.dev \
--cc=andrii@kernel.org \
--cc=ast@kernel.org \
--cc=bpf@vger.kernel.org \
--cc=chenyuan@kylinos.cn \
--cc=chenyuan_fl@163.com \
--cc=daniel@iogearbox.net \
--cc=eddyz87@gmail.com \
--cc=jolsa@kernel.org \
--cc=linux-kernel@vger.kernel.org \
--cc=martin.lau@linux.dev \
--cc=memxor@gmail.com \
--cc=song@kernel.org \
--cc=yonghong.song@linux.dev \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox
Powered by JetHome