From f8af75f3517a24838a36eb5797a1a3e60bf9e276 Mon Sep 17 00:00:00 2001 From: Eric Dumazet Date: Wed, 6 Mar 2013 11:02:37 +0000 Subject: [PATCH] tun: add a missing nf_reset() in tun_net_xmit() Dave reported following crash : general protection fault: 0000 [#1] SMP CPU 2 Pid: 25407, comm: qemu-kvm Not tainted 3.7.9-205.fc18.x86_64 #1 Hewlett-Packard HP Z400 Workstation/0B4Ch RIP: 0010:[] [] destroy_conntrack+0x35/0x120 [nf_conntrack] RSP: 0018:ffff880276913d78 EFLAGS: 00010206 RAX: 50626b6b7876376c RBX: ffff88026e530d68 RCX: ffff88028d158e00 RDX: ffff88026d0d5470 RSI: 0000000000000011 RDI: 0000000000000002 RBP: ffff880276913d88 R08: 0000000000000000 R09: ffff880295002900 R10: 0000000000000000 R11: 0000000000000003 R12: ffffffff81ca3b40 R13: ffffffff8151a8e0 R14: ffff880270875000 R15: 0000000000000002 FS: 00007ff3bce38a00(0000) GS:ffff88029fc40000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 000000008005003b CR2: 00007fd1430bd000 CR3: 000000027042b000 CR4: 00000000000027e0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000ffff0ff0 DR7: 0000000000000400 Process qemu-kvm (pid: 25407, threadinfo ffff880276912000, task ffff88028c369720) Stack: ffff880156f59100 ffff880156f59100 ffff880276913d98 ffffffff815534f7 ffff880276913db8 ffffffff8151a74b ffff880270875000 ffff880156f59100 ffff880276913dd8 ffffffff8151a5a6 ffff880276913dd8 ffff88026d0d5470 Call Trace: [] nf_conntrack_destroy+0x17/0x20 [] skb_release_head_state+0x7b/0x100 [] __kfree_skb+0x16/0xa0 [] kfree_skb+0x36/0xa0 [] skb_queue_purge+0x20/0x40 [] __tun_detach+0x117/0x140 [tun] [] tun_chr_close+0x3c/0xd0 [tun] [] __fput+0xec/0x240 [] ____fput+0xe/0x10 [] task_work_run+0xa7/0xe0 [] do_notify_resume+0x71/0xb0 [] int_signal+0x12/0x17 Code: 00 00 04 48 89 e5 41 54 53 48 89 fb 4c 8b a7 e8 00 00 00 0f 85 de 00 00 00 0f b6 73 3e 0f b7 7b 2a e8 10 40 00 00 48 85 c0 74 0e <48> 8b 40 28 48 85 c0 74 05 48 89 df ff d0 48 c7 c7 08 6a 3a a0 RIP [] destroy_conntrack+0x35/0x120 [nf_conntrack] RSP This is because tun_net_xmit() needs to call nf_reset() before queuing skb into receive_queue Reported-by: Dave Jones Signed-off-by: Eric Dumazet Signed-off-by: David S. Miller --- drivers/net/tun.c | 2 ++ 1 file changed, 2 insertions(+) diff --git a/drivers/net/tun.c b/drivers/net/tun.c index 2c6a22e278ea15..b7c457adc0dc74 100644 --- a/drivers/net/tun.c +++ b/drivers/net/tun.c @@ -747,6 +747,8 @@ static netdev_tx_t tun_net_xmit(struct sk_buff *skb, struct net_device *dev) goto drop; skb_orphan(skb); + nf_reset(skb); + /* Enqueue packet */ skb_queue_tail(&tfile->socket.sk->sk_receive_queue, skb);