From nobody Fri Dec 19 20:12:30 2025 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 9BDF515099B; Wed, 13 Mar 2024 16:46:55 +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=1710348415; cv=none; b=YzpTjxh6aUMiYaFHXEWL1kEOrkHAT7yVycXENfb+RHTxYBg69BIC0dyXPxyVuQ6pA0qZazNNq6W+JSy56NLJ2KxnfnqKgXzyyX0dh36MCU84Jm9TBXNcTwjDIXzxrQ0rsqFr8OTxX+iqpt5LDnupCpMR+fhCIEyOK8ZaKYWu1xk= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1710348415; c=relaxed/simple; bh=ikYP7GgT1Knk2KrrqCDL8WCKM7IMr/UR89wnWQF8slA=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=mZmNp3sVZeArA7d+dCqlqvU9oDStx2jeiGpnqSFPvygfxZQDvpFc8iTuwZnwRMBBp081vC1mGh0kCG5lDbAYKS1XnOWOlZ8hgiSck9AbNCzGnIcQdJz04/9dOVDK7W1HYVej2oHySK7ockl06Ja3dGze2VvW67WPhrixfYPML3k= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=mIMaSn75; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="mIMaSn75" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 974B1C433C7; Wed, 13 Mar 2024 16:46:54 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1710348415; bh=ikYP7GgT1Knk2KrrqCDL8WCKM7IMr/UR89wnWQF8slA=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=mIMaSn75o885/+TsPULMGzC3DIKcRA0zyGh4pqBa+yVVsQfCftdl5Pu0nkUoT0jmR 3oDODNELKyibhfFs0JlJFqLJx9bUIUSPZHkQFK/7gJl5CPBBnCjONso1IKjFejDdaT ye9qblH7e5t1hANZpJ1hhymjCUiFDh0y31x8EeEHCcn6sw9pFCaVJGiP73/ZZcZ5Yr IdGVgFxXjxreHiF/rmQEAAJHjlgmwPehy3ef4IKePQ9ZfXY8NpBSvNPs9Qa6pjlanL 7sKUUwXdA5qqkUyeTlP6+w0rPzI1T1yTTT8McwZBcuRP4JRIQN4JIB07AXcOsbsE41 e+7q1TKZT39VA== From: Sasha Levin To: linux-kernel@vger.kernel.org, stable@vger.kernel.org Cc: Eric Dumazet , syzbot+6a1423ff3f97159aae64@syzkaller.appspotmail.com, Jiri Pirko , "David S . Miller" , Sasha Levin Subject: [PATCH 5.10 11/73] geneve: make sure to pull inner header in geneve_rx() Date: Wed, 13 Mar 2024 12:45:38 -0400 Message-ID: <20240313164640.616049-12-sashal@kernel.org> X-Mailer: git-send-email 2.43.0 In-Reply-To: <20240313164640.616049-1-sashal@kernel.org> References: <20240313164640.616049-1-sashal@kernel.org> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 X-KernelTest-Patch: http://kernel.org/pub/linux/kernel/v5.x/stable-review/patch-5.10.213-rc1.gz X-KernelTest-Tree: git://git.kernel.org/pub/scm/linux/kernel/git/stable/linux-stable-rc.git X-KernelTest-Branch: linux-5.10.y X-KernelTest-Patches: git://git.kernel.org/pub/scm/linux/kernel/git/stable/stable-queue.git X-KernelTest-Version: 5.10.213-rc1 X-KernelTest-Deadline: 2024-03-15T16:46+00:00 X-stable: review X-Patchwork-Hint: Ignore Content-Transfer-Encoding: quoted-printable Content-Type: text/plain; charset="utf-8" From: Eric Dumazet [ Upstream commit 1ca1ba465e55b9460e4e75dec9fff31e708fec74 ] syzbot triggered a bug in geneve_rx() [1] Issue is similar to the one I fixed in commit 8d975c15c0cd ("ip6_tunnel: make sure to pull inner header in __ip6_tnl_rcv()") We have to save skb->network_header in a temporary variable in order to be able to recompute the network_header pointer after a pskb_inet_may_pull() call. pskb_inet_may_pull() makes sure the needed headers are in skb->head. [1] BUG: KMSAN: uninit-value in IP_ECN_decapsulate include/net/inet_ecn.h:302 [= inline] BUG: KMSAN: uninit-value in geneve_rx drivers/net/geneve.c:279 [inline] BUG: KMSAN: uninit-value in geneve_udp_encap_recv+0x36f9/0x3c10 drivers/ne= t/geneve.c:391 IP_ECN_decapsulate include/net/inet_ecn.h:302 [inline] geneve_rx drivers/net/geneve.c:279 [inline] geneve_udp_encap_recv+0x36f9/0x3c10 drivers/net/geneve.c:391 udp_queue_rcv_one_skb+0x1d39/0x1f20 net/ipv4/udp.c:2108 udp_queue_rcv_skb+0x6ae/0x6e0 net/ipv4/udp.c:2186 udp_unicast_rcv_skb+0x184/0x4b0 net/ipv4/udp.c:2346 __udp4_lib_rcv+0x1c6b/0x3010 net/ipv4/udp.c:2422 udp_rcv+0x7d/0xa0 net/ipv4/udp.c:2604 ip_protocol_deliver_rcu+0x264/0x1300 net/ipv4/ip_input.c:205 ip_local_deliver_finish+0x2b8/0x440 net/ipv4/ip_input.c:233 NF_HOOK include/linux/netfilter.h:314 [inline] ip_local_deliver+0x21f/0x490 net/ipv4/ip_input.c:254 dst_input include/net/dst.h:461 [inline] ip_rcv_finish net/ipv4/ip_input.c:449 [inline] NF_HOOK include/linux/netfilter.h:314 [inline] ip_rcv+0x46f/0x760 net/ipv4/ip_input.c:569 __netif_receive_skb_one_core net/core/dev.c:5534 [inline] __netif_receive_skb+0x1a6/0x5a0 net/core/dev.c:5648 process_backlog+0x480/0x8b0 net/core/dev.c:5976 __napi_poll+0xe3/0x980 net/core/dev.c:6576 napi_poll net/core/dev.c:6645 [inline] net_rx_action+0x8b8/0x1870 net/core/dev.c:6778 __do_softirq+0x1b7/0x7c5 kernel/softirq.c:553 do_softirq+0x9a/0xf0 kernel/softirq.c:454 __local_bh_enable_ip+0x9b/0xa0 kernel/softirq.c:381 local_bh_enable include/linux/bottom_half.h:33 [inline] rcu_read_unlock_bh include/linux/rcupdate.h:820 [inline] __dev_queue_xmit+0x2768/0x51c0 net/core/dev.c:4378 dev_queue_xmit include/linux/netdevice.h:3171 [inline] packet_xmit+0x9c/0x6b0 net/packet/af_packet.c:276 packet_snd net/packet/af_packet.c:3081 [inline] packet_sendmsg+0x8aef/0x9f10 net/packet/af_packet.c:3113 sock_sendmsg_nosec net/socket.c:730 [inline] __sock_sendmsg net/socket.c:745 [inline] __sys_sendto+0x735/0xa10 net/socket.c:2191 __do_sys_sendto net/socket.c:2203 [inline] __se_sys_sendto net/socket.c:2199 [inline] __x64_sys_sendto+0x125/0x1c0 net/socket.c:2199 do_syscall_x64 arch/x86/entry/common.c:52 [inline] do_syscall_64+0xcf/0x1e0 arch/x86/entry/common.c:83 entry_SYSCALL_64_after_hwframe+0x63/0x6b Uninit was created at: slab_post_alloc_hook mm/slub.c:3819 [inline] slab_alloc_node mm/slub.c:3860 [inline] kmem_cache_alloc_node+0x5cb/0xbc0 mm/slub.c:3903 kmalloc_reserve+0x13d/0x4a0 net/core/skbuff.c:560 __alloc_skb+0x352/0x790 net/core/skbuff.c:651 alloc_skb include/linux/skbuff.h:1296 [inline] alloc_skb_with_frags+0xc8/0xbd0 net/core/skbuff.c:6394 sock_alloc_send_pskb+0xa80/0xbf0 net/core/sock.c:2783 packet_alloc_skb net/packet/af_packet.c:2930 [inline] packet_snd net/packet/af_packet.c:3024 [inline] packet_sendmsg+0x70c2/0x9f10 net/packet/af_packet.c:3113 sock_sendmsg_nosec net/socket.c:730 [inline] __sock_sendmsg net/socket.c:745 [inline] __sys_sendto+0x735/0xa10 net/socket.c:2191 __do_sys_sendto net/socket.c:2203 [inline] __se_sys_sendto net/socket.c:2199 [inline] __x64_sys_sendto+0x125/0x1c0 net/socket.c:2199 do_syscall_x64 arch/x86/entry/common.c:52 [inline] do_syscall_64+0xcf/0x1e0 arch/x86/entry/common.c:83 entry_SYSCALL_64_after_hwframe+0x63/0x6b Fixes: 2d07dc79fe04 ("geneve: add initial netdev driver for GENEVE tunnels") Reported-and-tested-by: syzbot+6a1423ff3f97159aae64@syzkaller.appspotmail.c= om Signed-off-by: Eric Dumazet Reviewed-by: Jiri Pirko Signed-off-by: David S. Miller Signed-off-by: Sasha Levin --- drivers/net/geneve.c | 18 ++++++++++++++++-- 1 file changed, 16 insertions(+), 2 deletions(-) diff --git a/drivers/net/geneve.c b/drivers/net/geneve.c index 081939cb420b0..2bb9820c66641 100644 --- a/drivers/net/geneve.c +++ b/drivers/net/geneve.c @@ -218,7 +218,7 @@ static void geneve_rx(struct geneve_dev *geneve, struct= geneve_sock *gs, struct genevehdr *gnvh =3D geneve_hdr(skb); struct metadata_dst *tun_dst =3D NULL; unsigned int len; - int err =3D 0; + int nh, err =3D 0; void *oiph; =20 if (ip_tunnel_collect_metadata() || gs->collect_md) { @@ -262,9 +262,23 @@ static void geneve_rx(struct geneve_dev *geneve, struc= t geneve_sock *gs, goto drop; } =20 - oiph =3D skb_network_header(skb); + /* Save offset of outer header relative to skb->head, + * because we are going to reset the network header to the inner header + * and might change skb->head. + */ + nh =3D skb_network_header(skb) - skb->head; + skb_reset_network_header(skb); =20 + if (!pskb_inet_may_pull(skb)) { + DEV_STATS_INC(geneve->dev, rx_length_errors); + DEV_STATS_INC(geneve->dev, rx_errors); + goto drop; + } + + /* Get the outer header. */ + oiph =3D skb->head + nh; + if (geneve_get_sk_family(gs) =3D=3D AF_INET) err =3D IP_ECN_decapsulate(oiph, skb); #if IS_ENABLED(CONFIG_IPV6) --=20 2.43.0