From: Jakub Kicinski <kuba@kernel.org>
To: Jiayuan Chen <jiayuan.chen@linux.dev>
Cc: bpf@vger.kernel.org, netdev@vger.kernel.org,
syzbot+237bbeed8dfe0699b7f5@syzkaller.appspotmail.com,
"Andrew Lunn" <andrew+netdev@lunn.ch>,
"David S. Miller" <davem@davemloft.net>,
"Eric Dumazet" <edumazet@google.com>,
"Paolo Abeni" <pabeni@redhat.com>,
"Alexei Starovoitov" <ast@kernel.org>,
"Daniel Borkmann" <daniel@iogearbox.net>,
"Jesper Dangaard Brouer" <hawk@kernel.org>,
"John Fastabend" <john.fastabend@gmail.com>,
"Stanislav Fomichev" <sdf@fomichev.me>,
"Simon Horman" <horms@kernel.org>,
"Martin KaFai Lau" <martin.lau@linux.dev>,
"Andrii Nakryiko" <andrii@kernel.org>,
"Eduard Zingerman" <eddyz87@gmail.com>,
"Kumar Kartikeya Dwivedi" <memxor@gmail.com>,
"Song Liu" <song@kernel.org>,
"Yonghong Song" <yonghong.song@linux.dev>,
"Jiri Olsa" <jolsa@kernel.org>,
"Emil Tsalapatis" <emil@etsalapatis.com>,
"Ihor Solodrai" <ihor.solodrai@linux.dev>,
"Shuah Khan" <shuah@kernel.org>,
"Kuniyuki Iwashima" <kuniyu@google.com>,
"Hangbin Liu" <liuhangbin@gmail.com>,
"Krishna Kumar" <krikku@gmail.com>,
"Martin Karsten" <mkarsten@uwaterloo.ca>,
"Toke Høiland-Jørgensen" <toke@redhat.com>,
"Lorenzo Bianconi" <lorenzo.bianconi@oss.qualcomm.com>,
linux-kernel@vger.kernel.org, linux-kselftest@vger.kernel.org
Subject: Re: [PATCH bpf v2 1/2] bpf, veth: xdp: fix page_pool page leak on skb-backed XDP
Date: Thu, 27 Aug 2026 12:20:14 -0700 [thread overview]
Message-ID: <20260827122014.79ac1694@kernel.org> (raw)
In-Reply-To: <20260824030705.266049-1-jiayuan.chen@linux.dev>
On Mon, 24 Aug 2026 11:06:43 +0800 Jiayuan Chen wrote:
> bpf_xdp_shrink_data() frees a released frag via __xdp_return() using
> xdp->rxq->mem.type, but that type is wrong for skb-backed XDP: the skb is
> cow'd into page_pool memory while the rxq still says MEM_TYPE_PAGE_SHARED,
> so the page_pool page is freed with page_frag_free() and we hit
> "Bad page state ... page_pool leak".
FWIW I like the idea if it can be made to work fully correctly.
prev parent reply other threads:[~2026-08-27 19:20 UTC|newest]
Thread overview: 12+ messages / expand[flat|nested] mbox.gz Atom feed top
2026-08-24 3:02 [PATCH bpf v2 0/2] net: xdp: fix bpf_xdp_shrink_data() page handling on generic XDP and veth Jiayuan Chen
2026-08-24 3:06 ` [PATCH bpf v2 1/2] bpf, veth: xdp: fix page_pool page leak on skb-backed XDP Jiayuan Chen
2026-08-24 3:06 ` [PATCH bpf v2 2/2] selftests/bpf: add xdp_shrink_frags Jiayuan Chen
2026-08-24 3:58 ` bot+bpf-ci
2026-08-24 4:53 ` Jiayuan Chen
2026-08-27 19:19 ` Jakub Kicinski
2026-08-24 10:31 ` [PATCH bpf v2 1/2] bpf, veth: xdp: fix page_pool page leak on skb-backed XDP Lorenzo Bianconi
2026-08-24 12:19 ` Jiayuan Chen
2026-08-24 14:50 ` Lorenzo Bianconi
2026-08-25 12:06 ` Jiayuan Chen
2026-08-27 19:19 ` Jakub Kicinski
2026-08-27 19:20 ` Jakub Kicinski [this message]
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