This is a note to let you know that I've just added the patch titled vrf: fix bug_on triggered by rx when destroying a vrf to the 4.11-stable tree which can be found at: http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary The filename of the patch is: vrf-fix-bug_on-triggered-by-rx-when-destroying-a-vrf.patch and it can be found in the queue-4.11 subdirectory. If you, or anyone else, feels it should not be added to the stable tree, please let <stable@xxxxxxxxxxxxxxx> know about it. >From foo@baz Mon Jul 17 18:47:09 CEST 2017 From: Nikolay Aleksandrov <nikolay@xxxxxxxxxxxxxxxxxxx> Date: Thu, 6 Jul 2017 15:24:40 +0300 Subject: vrf: fix bug_on triggered by rx when destroying a vrf From: Nikolay Aleksandrov <nikolay@xxxxxxxxxxxxxxxxxxx> [ Upstream commit f630c38ef0d785101363a8992bbd4f302180f86f ] When destroying a VRF device we cleanup the slaves in its ndo_uninit() function, but that causes packets to be switched (skb->dev == vrf being destroyed) even though we're pass the point where the VRF should be receiving any packets while it is being dismantled. This causes a BUG_ON to trigger if we have raw sockets (trace below). The reason is that the inetdev of the VRF has been destroyed but we're still sending packets up the stack with it, so let's free the slaves in the dellink callback as David Ahern suggested. Note that this fix doesn't prevent packets from going up when the VRF device is admin down. [ 35.631371] ------------[ cut here ]------------ [ 35.631603] kernel BUG at net/ipv4/fib_frontend.c:285! [ 35.631854] invalid opcode: 0000 [#1] SMP [ 35.631977] Modules linked in: [ 35.632081] CPU: 2 PID: 22 Comm: ksoftirqd/2 Not tainted 4.12.0-rc7+ #45 [ 35.632247] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.7.5-20140531_083030-gandalf 04/01/2014 [ 35.632477] task: ffff88005ad68000 task.stack: ffff88005ad64000 [ 35.632632] RIP: 0010:fib_compute_spec_dst+0xfc/0x1ee [ 35.632769] RSP: 0018:ffff88005ad67978 EFLAGS: 00010202 [ 35.632910] RAX: 0000000000000001 RBX: ffff880059a7f200 RCX: 0000000000000000 [ 35.633084] RDX: 0000000000000000 RSI: 0000000000000001 RDI: ffffffff82274af0 [ 35.633256] RBP: ffff88005ad679f8 R08: 000000000001ef70 R09: 0000000000000046 [ 35.633430] R10: ffff88005ad679f8 R11: ffff880037731cb0 R12: 0000000000000001 [ 35.633603] R13: ffff8800599e3000 R14: 0000000000000000 R15: ffff8800599cb852 [ 35.634114] FS: 0000000000000000(0000) GS:ffff88005d900000(0000) knlGS:0000000000000000 [ 35.634306] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [ 35.634456] CR2: 00007f3563227095 CR3: 000000000201d000 CR4: 00000000000406e0 [ 35.634632] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 [ 35.634865] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 [ 35.635055] Call Trace: [ 35.635271] ? __lock_acquire+0xf0d/0x1117 [ 35.635522] ipv4_pktinfo_prepare+0x82/0x151 [ 35.635831] raw_rcv_skb+0x17/0x3c [ 35.636062] raw_rcv+0xe5/0xf7 [ 35.636287] raw_local_deliver+0x169/0x1d9 [ 35.636534] ip_local_deliver_finish+0x87/0x1c4 [ 35.636820] ip_local_deliver+0x63/0x7f [ 35.637058] ip_rcv_finish+0x340/0x3a1 [ 35.637295] ip_rcv+0x314/0x34a [ 35.637525] __netif_receive_skb_core+0x49f/0x7c5 [ 35.637780] ? lock_acquire+0x13f/0x1d7 [ 35.638018] ? lock_acquire+0x15e/0x1d7 [ 35.638259] __netif_receive_skb+0x1e/0x94 [ 35.638502] ? __netif_receive_skb+0x1e/0x94 [ 35.638748] netif_receive_skb_internal+0x74/0x300 [ 35.639002] ? dev_gro_receive+0x2ed/0x411 [ 35.639246] ? lock_is_held_type+0xc4/0xd2 [ 35.639491] napi_gro_receive+0x105/0x1a0 [ 35.639736] receive_buf+0xc32/0xc74 [ 35.639965] ? detach_buf+0x67/0x153 [ 35.640201] ? virtqueue_get_buf_ctx+0x120/0x176 [ 35.640453] virtnet_poll+0x128/0x1c5 [ 35.640690] net_rx_action+0x103/0x343 [ 35.640932] __do_softirq+0x1c7/0x4b7 [ 35.641171] run_ksoftirqd+0x23/0x5c [ 35.641403] smpboot_thread_fn+0x24f/0x26d [ 35.641646] ? sort_range+0x22/0x22 [ 35.641878] kthread+0x129/0x131 [ 35.642104] ? __list_add+0x31/0x31 [ 35.642335] ? __list_add+0x31/0x31 [ 35.642568] ret_from_fork+0x2a/0x40 [ 35.642804] Code: 05 bd 87 a3 00 01 e8 1f ef 98 ff 4d 85 f6 48 c7 c7 f0 4a 27 82 41 0f 94 c4 31 c9 31 d2 41 0f b6 f4 e8 04 71 a1 ff 45 84 e4 74 02 <0f> 0b 0f b7 93 c4 00 00 00 4d 8b a5 80 05 00 00 48 03 93 d0 00 [ 35.644342] RIP: fib_compute_spec_dst+0xfc/0x1ee RSP: ffff88005ad67978 Fixes: 193125dbd8eb ("net: Introduce VRF device driver") Reported-by: Chris Cormier <chriscormier@xxxxxxxxxxxxxxxxxxx> Signed-off-by: Nikolay Aleksandrov <nikolay@xxxxxxxxxxxxxxxxxxx> Acked-by: David Ahern <dsahern@xxxxxxxxx> Signed-off-by: David S. Miller <davem@xxxxxxxxxxxxx> Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> --- drivers/net/vrf.c | 11 ++++++----- 1 file changed, 6 insertions(+), 5 deletions(-) --- a/drivers/net/vrf.c +++ b/drivers/net/vrf.c @@ -788,15 +788,10 @@ static int vrf_del_slave(struct net_devi static void vrf_dev_uninit(struct net_device *dev) { struct net_vrf *vrf = netdev_priv(dev); - struct net_device *port_dev; - struct list_head *iter; vrf_rtable_release(dev, vrf); vrf_rt6_release(dev, vrf); - netdev_for_each_lower_dev(dev, port_dev, iter) - vrf_del_slave(dev, port_dev); - free_percpu(dev->dstats); dev->dstats = NULL; } @@ -1247,6 +1242,12 @@ static int vrf_validate(struct nlattr *t static void vrf_dellink(struct net_device *dev, struct list_head *head) { + struct net_device *port_dev; + struct list_head *iter; + + netdev_for_each_lower_dev(dev, port_dev, iter) + vrf_del_slave(dev, port_dev); + unregister_netdevice_queue(dev, head); } Patches currently in stable-queue which might be from nikolay@xxxxxxxxxxxxxxxxxxx are queue-4.11/vrf-fix-bug_on-triggered-by-rx-when-destroying-a-vrf.patch