From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (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 D11C62E62D1; Tue, 15 Jul 2025 13:26:25 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1752585985; cv=none; b=JwOc9rKaE6uWGQZ4BuPdxrKOZO4IOcZKYAQf5Zuz43OQq4nnm4JlJ1li53d1cgO3DIFLi/QD5+YBp8EYKdbGogOMPqwaHargmuiyJNe0btkcWc8uMq61/iZWozw367WRCqGH8Q4ltD3CSZfBpUWi2/Z8tUFKckbhG8JUywTqVv0= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1752585985; c=relaxed/simple; bh=5W2aCr8nEkOJ2UMam1uw7Wn9RBSbZyfKlyvHbWDGq2k=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=Tn5ybwmL27dP7yuq01M6rTJUliMrsA7Kbl1O9TIUj1R2VlvM4apNAcqjHVPg433egeaYycaaCEL7h8BKZbhD3SuWKoXGPHzCHs5fHg+ukAYlnuVUQQ0g78l+PpTCzdah+RzpnLsIVI+EkE0/4zVkwzRPHquJ91pYkvT+ucCDk+s= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b=nUMDnmnE; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b="nUMDnmnE" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 61CA1C4CEE3; Tue, 15 Jul 2025 13:26:25 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1752585985; bh=5W2aCr8nEkOJ2UMam1uw7Wn9RBSbZyfKlyvHbWDGq2k=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=nUMDnmnEUpEc0/f2/JaoYwn9wTVSy1/TQw5KoYv1BZ1JOjvSE4cCVmfeBE0onfNHe yo6CevEe9s3rcZpt7YGXGv60sMYiwSMcWXJ9370N8gDhlKRLOjKVGOkEYf61hj1UZJ 5UQIe0i23/VgJVlsZCrY768S09iy7ZD9ZJpv83mg= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, syzbot+bf6ed459397e307c3ad2@syzkaller.appspotmail.com, Eric Dumazet , Pablo Neira Ayuso , Jakub Kicinski , Sasha Levin Subject: [PATCH 6.6 083/109] netfilter: flowtable: account for Ethernet header in nf_flow_pppoe_proto() Date: Tue, 15 Jul 2025 15:13:39 +0200 Message-ID: <20250715130802.203864312@linuxfoundation.org> X-Mailer: git-send-email 2.50.1 In-Reply-To: <20250715130758.864940641@linuxfoundation.org> References: <20250715130758.864940641@linuxfoundation.org> User-Agent: quilt/0.68 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 6.6-stable review patch. If anyone has any objections, please let me know. ------------------ From: Eric Dumazet [ Upstream commit 18cdb3d982da8976b28d57691eb256ec5688fad2 ] syzbot found a potential access to uninit-value in nf_flow_pppoe_proto() Blamed commit forgot the Ethernet header. BUG: KMSAN: uninit-value in nf_flow_offload_inet_hook+0x7e4/0x940 net/netfilter/nf_flow_table_inet.c:27 nf_flow_offload_inet_hook+0x7e4/0x940 net/netfilter/nf_flow_table_inet.c:27 nf_hook_entry_hookfn include/linux/netfilter.h:157 [inline] nf_hook_slow+0xe1/0x3d0 net/netfilter/core.c:623 nf_hook_ingress include/linux/netfilter_netdev.h:34 [inline] nf_ingress net/core/dev.c:5742 [inline] __netif_receive_skb_core+0x4aff/0x70c0 net/core/dev.c:5837 __netif_receive_skb_one_core net/core/dev.c:5975 [inline] __netif_receive_skb+0xcc/0xac0 net/core/dev.c:6090 netif_receive_skb_internal net/core/dev.c:6176 [inline] netif_receive_skb+0x57/0x630 net/core/dev.c:6235 tun_rx_batched+0x1df/0x980 drivers/net/tun.c:1485 tun_get_user+0x4ee0/0x6b40 drivers/net/tun.c:1938 tun_chr_write_iter+0x3e9/0x5c0 drivers/net/tun.c:1984 new_sync_write fs/read_write.c:593 [inline] vfs_write+0xb4b/0x1580 fs/read_write.c:686 ksys_write fs/read_write.c:738 [inline] __do_sys_write fs/read_write.c:749 [inline] Reported-by: syzbot+bf6ed459397e307c3ad2@syzkaller.appspotmail.com Closes: https://lore.kernel.org/netdev/686bc073.a00a0220.c7b3.0086.GAE@google.com/T/#u Fixes: 87b3593bed18 ("netfilter: flowtable: validate pppoe header") Signed-off-by: Eric Dumazet Reviewed-by: Pablo Neira Ayuso Link: https://patch.msgid.link/20250707124517.614489-1-edumazet@google.com Signed-off-by: Jakub Kicinski Signed-off-by: Sasha Levin --- include/net/netfilter/nf_flow_table.h | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/include/net/netfilter/nf_flow_table.h b/include/net/netfilter/nf_flow_table.h index df7775afb92b9..0097791e1eede 100644 --- a/include/net/netfilter/nf_flow_table.h +++ b/include/net/netfilter/nf_flow_table.h @@ -353,7 +353,7 @@ static inline __be16 __nf_flow_pppoe_proto(const struct sk_buff *skb) static inline bool nf_flow_pppoe_proto(struct sk_buff *skb, __be16 *inner_proto) { - if (!pskb_may_pull(skb, PPPOE_SES_HLEN)) + if (!pskb_may_pull(skb, ETH_HLEN + PPPOE_SES_HLEN)) return false; *inner_proto = __nf_flow_pppoe_proto(skb); -- 2.39.5