From: Martin KaFai Lau <martin.lau@linux.dev>
To: Nick Hudson <nhudson@akamai.com>, sashiko@lists.linux.dev
Cc: bpf@vger.kernel.org
Subject: Re: [PATCH bpf-next v4 6/6] selftests/bpf: tc_tunnel validate decap GSO state
Date: Thu, 16 Apr 2026 12:46:53 -0700 [thread overview]
Message-ID: <2026416193859.IJ9_.martin.lau@linux.dev> (raw)
In-Reply-To: <20260416124324.B0CE6C2BCAF@smtp.kernel.org>
On Thu, Apr 16, 2026 at 12:43:24PM +0000, sashiko-bot@kernel.org wrote:
> Sashiko AI review found 3 potential issue(s):
> - [Low] Invalid pointer arithmetic (`kskb->head + kskb->end`) causes a compilation failure on 32-bit architectures.
> > @@ -655,6 +684,35 @@ static int decap_internal(struct __sk_buff *skb, int off, int len, char proto)
> > if (bpf_skb_adjust_room(skb, -olen, BPF_ADJ_ROOM_MAC, flags))
> > return TC_ACT_SHOT;
> >
> > + kskb = bpf_cast_to_kern_ctx(skb);
> > + shinfo = bpf_core_cast(kskb->head + kskb->end, struct skb_shared_info);
>
> Will this cause a compilation failure on 32-bit architectures?
>
> On 32-bit architectures without NET_SKBUFF_DATA_USES_OFFSET, sk_buff::end
> is defined as a pointer (unsigned char *) rather than an offset. Adding two
> pointers is an invalid operation in C and will result in a build error.
Other tests have been using it to get shinfo already. I would leave it as is.
If it really would be needed to run and compile on 32-bit in the future,
it could use bpf_core_field_size(kskb->end) and then do things differently.
parent reply other threads:[~2026-04-16 19:47 UTC|newest]
Thread overview: expand[flat|nested] mbox.gz Atom feed
[parent not found: <20260416124324.B0CE6C2BCAF@smtp.kernel.org>]
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=2026416193859.IJ9_.martin.lau@linux.dev \
--to=martin.lau@linux.dev \
--cc=bpf@vger.kernel.org \
--cc=nhudson@akamai.com \
--cc=sashiko@lists.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