From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-alma10-1.taild15c8.ts.net [100.103.45.18]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 02D073D6673; Wed, 20 May 2026 17:24:17 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=100.103.45.18 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1779297858; cv=none; b=Ukl50wRHSFZ+31KC/RrI8aQ/iL5SSv8rM1wmWQcmdCxNS7pktFQltWHEVpyb1NucTkHDE2QJK+SAheVvBIEHZQ6ZKUw6WonKrbWwvbrKhn4j0XE/j2fXFM8wjscNygRHf1HLADGqwaxyCoV5aTDgVVfCcvhUU7iZPOu8OLAgQoM= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1779297858; c=relaxed/simple; bh=7XpovQe+dD3ZBJ2oOeSo+Q+jUkyeiGcSnopPU8SKgp4=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=Zk4bo80lxbgjkwwlDAJl+iqzl79wFlrqbNAIY9IXbFGF9+4DsjbKokOi9Cykpz49XZpCK+Pe9DvbQPemTUYModcN4aDyOmeLoHJu2p3nEM3DSG7Du/LE/8TXwVaX9Dfg8X6NUTiTwxQnhI84KAufiHTcOJMmcXFT2HcqW5Soi+k= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b=1Um0jtsa; arc=none smtp.client-ip=100.103.45.18 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b="1Um0jtsa" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 695B21F000E9; Wed, 20 May 2026 17:24:16 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linuxfoundation.org; s=korg; t=1779297856; bh=Ib4CzhFkPyAkC+0pZkL0v46Ty63HOLBWdPPyuyFsuX4=; h=From:To:Cc:Subject:Date:In-Reply-To:References; b=1Um0jtsay4ZGO8SPOj5v46ZQ8dgMywsGCkaXFaVvPI/6kt4nszwBquZNSX+lo6aSZ mx7mpBMuczFFi/1roHPv8OgWLhIHVEulCrn0blE5xT8SzJNmQ6Q4Wwp1nQ8tpPd6jf btYwjrSqjE00Dl2Z0CqTRlm/T8A/b6I3hKx/xEpo= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, syzbot+619b9ef527f510a57cfc@syzkaller.appspotmail.com, Sun Jian , Alexei Starovoitov , Sasha Levin Subject: [PATCH 6.18 173/957] bpf: reject short IPv4/IPv6 inputs in bpf_prog_test_run_skb Date: Wed, 20 May 2026 18:10:56 +0200 Message-ID: <20260520162138.306507736@linuxfoundation.org> X-Mailer: git-send-email 2.54.0 In-Reply-To: <20260520162134.554764788@linuxfoundation.org> References: <20260520162134.554764788@linuxfoundation.org> User-Agent: quilt/0.69 X-stable: review X-Patchwork-Hint: ignore Precedence: bulk X-Mailing-List: patches@lists.linux.dev List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit 6.18-stable review patch. If anyone has any objections, please let me know. ------------------ From: Sun Jian [ Upstream commit 12bec2bd4b76d81c5d3996bd14ec1b7f4d983747 ] bpf_prog_test_run_skb() calls eth_type_trans() first and then uses skb->protocol to initialize sk family and address fields for the test run. For IPv4 and IPv6 packets, it may access ip_hdr(skb) or ipv6_hdr(skb) even when the provided test input only contains an Ethernet header. Reject the input earlier if the Ethernet frame carries IPv4/IPv6 EtherType but the L3 header is too short. Fold the IPv4/IPv6 header length checks into the existing protocol switch and return -EINVAL before accessing the network headers. Fixes: fa5cb548ced6 ("bpf: Setup socket family and addresses in bpf_prog_test_run_skb") Reported-by: syzbot+619b9ef527f510a57cfc@syzkaller.appspotmail.com Closes: https://syzkaller.appspot.com/bug?extid=619b9ef527f510a57cfc Signed-off-by: Sun Jian Link: https://lore.kernel.org/r/20260408034623.180320-2-sun.jian.kdev@gmail.com Signed-off-by: Alexei Starovoitov Signed-off-by: Sasha Levin --- net/bpf/test_run.c | 20 ++++++++++++-------- 1 file changed, 12 insertions(+), 8 deletions(-) diff --git a/net/bpf/test_run.c b/net/bpf/test_run.c index 65d7f8d51823e..963fee5d01e24 100644 --- a/net/bpf/test_run.c +++ b/net/bpf/test_run.c @@ -1057,19 +1057,23 @@ int bpf_prog_test_run_skb(struct bpf_prog *prog, const union bpf_attr *kattr, switch (skb->protocol) { case htons(ETH_P_IP): - sk->sk_family = AF_INET; - if (sizeof(struct iphdr) <= skb_headlen(skb)) { - sk->sk_rcv_saddr = ip_hdr(skb)->saddr; - sk->sk_daddr = ip_hdr(skb)->daddr; + if (skb_headlen(skb) < sizeof(struct iphdr)) { + ret = -EINVAL; + goto out; } + sk->sk_family = AF_INET; + sk->sk_rcv_saddr = ip_hdr(skb)->saddr; + sk->sk_daddr = ip_hdr(skb)->daddr; break; #if IS_ENABLED(CONFIG_IPV6) case htons(ETH_P_IPV6): - sk->sk_family = AF_INET6; - if (sizeof(struct ipv6hdr) <= skb_headlen(skb)) { - sk->sk_v6_rcv_saddr = ipv6_hdr(skb)->saddr; - sk->sk_v6_daddr = ipv6_hdr(skb)->daddr; + if (skb_headlen(skb) < sizeof(struct ipv6hdr)) { + ret = -EINVAL; + goto out; } + sk->sk_family = AF_INET6; + sk->sk_v6_rcv_saddr = ipv6_hdr(skb)->saddr; + sk->sk_v6_daddr = ipv6_hdr(skb)->daddr; break; #endif default: -- 2.53.0