2.6.32-longterm review patch. If anyone has any objections, please let me know. ------------------ AF_INET pending data From: Hannes Frederic Sowa <hannes@xxxxxxxxxxxxxxxxxxx> CVE-2013-4162 BugLink: http://bugs.launchpad.net/bugs/1205070 We accidentally call down to ip6_push_pending_frames when uncorking pending AF_INET data on a ipv6 socket. This results in the following splat (from Dave Jones): skbuff: skb_under_panic: text:ffffffff816765f6 len:48 put:40 head:ffff88013deb6df0 data:ffff88013deb6dec tail:0x2c end:0xc0 dev:<NULL> ------------[ cut here ]------------ kernel BUG at net/core/skbuff.c:126! invalid opcode: 0000 [#1] PREEMPT SMP DEBUG_PAGEALLOC Modules linked in: dccp_ipv4 dccp 8021q garp bridge stp dlci mpoa snd_seq_dummy sctp fuse hidp tun bnep nfnetlink scsi_transport_iscsi rfcomm can_raw can_bcm af_802154 appletalk caif_socket can caif ipt_ULOG x25 rose af_key pppoe pppox ipx phonet irda llc2 ppp_generic slhc p8023 psnap p8022 llc crc_ccitt atm bluetooth +netrom ax25 nfc rfkill rds af_rxrpc coretemp hwmon kvm_intel kvm crc32c_intel snd_hda_codec_realtek ghash_clmulni_intel microcode pcspkr snd_hda_codec_hdmi snd_hda_intel snd_hda_codec snd_hwdep usb_debug snd_seq snd_seq_device snd_pcm e1000e snd_page_alloc snd_timer ptp snd pps_core soundcore xfs libcrc32c CPU: 2 PID: 8095 Comm: trinity-child2 Not tainted 3.10.0-rc7+ #37 task: ffff8801f52c2520 ti: ffff8801e6430000 task.ti: ffff8801e6430000 RIP: 0010:[<ffffffff816e759c>] [<ffffffff816e759c>] skb_panic+0x63/0x65 RSP: 0018:ffff8801e6431de8 EFLAGS: 00010282 RAX: 0000000000000086 RBX: ffff8802353d3cc0 RCX: 0000000000000006 RDX: 0000000000003b90 RSI: ffff8801f52c2ca0 RDI: ffff8801f52c2520 RBP: ffff8801e6431e08 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000001 R11: 0000000000000001 R12: ffff88022ea0c800 R13: ffff88022ea0cdf8 R14: ffff8802353ecb40 R15: ffffffff81cc7800 FS: 00007f5720a10740(0000) GS:ffff880244c00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000000005862000 CR3: 000000022843c000 CR4: 00000000001407e0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000600 Stack: ffff88013deb6dec 000000000000002c 00000000000000c0 ffffffff81a3f6e4 ffff8801e6431e18 ffffffff8159a9aa ffff8801e6431e90 ffffffff816765f6 ffffffff810b756b 0000000700000002 ffff8801e6431e40 0000fea9292aa8c0 Call Trace: [<ffffffff8159a9aa>] skb_push+0x3a/0x40 [<ffffffff816765f6>] ip6_push_pending_frames+0x1f6/0x4d0 [<ffffffff810b756b>] ? mark_held_locks+0xbb/0x140 [<ffffffff81694919>] udp_v6_push_pending_frames+0x2b9/0x3d0 [<ffffffff81694660>] ? udplite_getfrag+0x20/0x20 [<ffffffff8162092a>] udp_lib_setsockopt+0x1aa/0x1f0 [<ffffffff811cc5e7>] ? fget_light+0x387/0x4f0 [<ffffffff816958a4>] udpv6_setsockopt+0x34/0x40 [<ffffffff815949f4>] sock_common_setsockopt+0x14/0x20 [<ffffffff81593c31>] SyS_setsockopt+0x71/0xd0 [<ffffffff816f5d54>] tracesys+0xdd/0xe2 Code: 00 00 48 89 44 24 10 8b 87 d8 00 00 00 48 89 44 24 08 48 8b 87 e8 00 00 00 48 c7 c7 c0 04 aa 81 48 89 04 24 31 c0 e8 e1 7e ff ff <0f> 0b 55 48 89 e5 0f 0b 55 48 89 e5 0f 0b 55 48 89 e5 0f 0b 55 RIP [<ffffffff816e759c>] skb_panic+0x63/0x65 RSP <ffff8801e6431de8> This patch adds a check if the pending data is of address family AF_INET and directly calls udp_push_ending_frames from udp_v6_push_pending_frames if that is the case. This bug was found by Dave Jones with trinity. (Also move the initialization of fl6 below the AF_INET check, even if not strictly necessary.) Cc: Dave Jones <davej@xxxxxxxxxx> Cc: YOSHIFUJI Hideaki <yoshfuji@xxxxxxxxxxxxxx> Signed-off-by: Hannes Frederic Sowa <hannes@xxxxxxxxxxxxxxxxxxx> Signed-off-by: David S. Miller <davem@xxxxxxxxxxxxx> (back ported from commit 8822b64a0fa64a5dd1dfcf837c5b0be83f8c05d1) Signed-off-by: Luis Henriques <luis.henriques@xxxxxxxxxxxxx> Acked-by: Brad Figg <brad.figg@xxxxxxxxxxxxx> Signed-off-by: Tim Gardner <tim.gardner@xxxxxxxxxxxxx> Signed-off-by: Willy Tarreau <w@xxxxxx> --- include/net/udp.h | 1 + net/ipv4/udp.c | 3 ++- net/ipv6/udp.c | 7 ++++++- 3 files changed, 9 insertions(+), 2 deletions(-) diff --git a/include/net/udp.h b/include/net/udp.h index f98abd2..702bea0 100644 --- a/include/net/udp.h +++ b/include/net/udp.h @@ -134,6 +134,7 @@ extern void udp_err(struct sk_buff *, u32); extern int udp_sendmsg(struct kiocb *iocb, struct sock *sk, struct msghdr *msg, size_t len); +extern int udp_push_pending_frames(struct sock *sk); extern void udp_flush_pending_frames(struct sock *sk); extern int udp_rcv(struct sk_buff *skb); diff --git a/net/ipv4/udp.c b/net/ipv4/udp.c index dba3c01..0b2e07f 100644 --- a/net/ipv4/udp.c +++ b/net/ipv4/udp.c @@ -513,7 +513,7 @@ static void udp4_hwcsum_outgoing(struct sock *sk, struct sk_buff *skb, /* * Push out all pending data as one UDP datagram. Socket is locked. */ -static int udp_push_pending_frames(struct sock *sk) +int udp_push_pending_frames(struct sock *sk) { struct udp_sock *up = udp_sk(sk); struct inet_sock *inet = inet_sk(sk); @@ -575,6 +575,7 @@ out: up->pending = 0; return err; } +EXPORT_SYMBOL(udp_push_pending_frames); int udp_sendmsg(struct kiocb *iocb, struct sock *sk, struct msghdr *msg, size_t len) diff --git a/net/ipv6/udp.c b/net/ipv6/udp.c index 3a91859..d0367eb 100644 --- a/net/ipv6/udp.c +++ b/net/ipv6/udp.c @@ -687,11 +687,16 @@ static int udp_v6_push_pending_frames(struct sock *sk) struct udphdr *uh; struct udp_sock *up = udp_sk(sk); struct inet_sock *inet = inet_sk(sk); - struct flowi *fl = &inet->cork.fl; + struct flowi *fl; int err = 0; int is_udplite = IS_UDPLITE(sk); __wsum csum = 0; + if (up->pending == AF_INET) + return udp_push_pending_frames(sk); + + fl = &inet->cork.fl; + /* Grab the skbuff where UDP header space exists. */ if ((skb = skb_peek(&sk->sk_write_queue)) == NULL) goto out; -- 1.7.12.2.21.g234cd45.dirty -- To unsubscribe from this list: send the line "unsubscribe stable" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html