user/sven/linux.git/drivers/net/vrf.c, branch v4.4.294

net: vrf: Fix dst reference counting

2020-05-10T08:26:22Z

commit 9ab179d83b4e31ea277a123492e419067c2f129a upstream. Vivek reported a kernel exception deleting a VRF with an active connection through it. The root cause is that the socket has a cached reference to a dst that is destroyed. Converting the dst_destroy to dst_release and letting proper reference counting kick in does not work as the dst has a reference to the device which needs to be released as well. I talked to Hannes about this at netdev and he pointed out the ipv4 and ipv6 dst handling has dst_ifdown for just this scenario. Rather than continuing with the reinvented dst wheel in VRF just remove it and leverage the ipv4 and ipv6 versions. Fixes: 193125dbd8eb2 ("net: Introduce VRF device driver") Fixes: 35402e3136634 ("net: Add IPv6 support to VRF device") Signed-off-by: David Ahern Signed-off-by: David S. Miller Signed-off-by: Greg Kroah-Hartman

vrf: Fix use after free and double free in vrf_finish_output

2018-04-13T17:50:27Z

commit 82dd0d2a9a76fc8fa2b18d80b987d455728bf83a upstream. Miguel reported an skb use after free / double free in vrf_finish_output when neigh_output returns an error. The vrf driver should return after the call to neigh_output as it takes over the skb on error path as well. Patch is a simplified version of Miguel's patch which was written for 4.9, and updated to top of tree. Fixes: 8f58336d3f78a ("net: Add ethernet header for pass through VRF device") Signed-off-by: Miguel Fadon Perlines Signed-off-by: David Ahern Signed-off-by: David S. Miller [ backport to 4.4 and 4.9 dropped the sock_confirm_neigh and changed neigh_output to dst_neigh_output ] Signed-off-by: Greg Kroah-Hartman

vrf: fix bug_on triggered by rx when destroying a vrf

2017-07-21T05:44:55Z

commit f630c38ef0d785101363a8992bbd4f302180f86f upstream. 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 Signed-off-by: Nikolay Aleksandrov Acked-by: David Ahern Signed-off-by: David S. Miller [backport to 4.4 - gregkh] Signed-off-by: Greg Kroah-Hartman

vrf: Fix use-after-free in vrf_xmit

2017-03-22T11:04:16Z

[ Upstream commit f7887d40e541f74402df0684a1463c0a0bb68c68 ] KASAN detected a use-after-free: [ 269.467067] BUG: KASAN: use-after-free in vrf_xmit+0x7f1/0x827 [vrf] at addr ffff8800350a21c0 [ 269.467067] Read of size 4 by task ssh/1879 [ 269.467067] CPU: 1 PID: 1879 Comm: ssh Not tainted 4.10.0+ #249 [ 269.467067] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.7.5-20140531_083030-gandalf 04/01/2014 [ 269.467067] Call Trace: [ 269.467067] dump_stack+0x81/0xb6 [ 269.467067] kasan_object_err+0x21/0x78 [ 269.467067] kasan_report+0x2f7/0x450 [ 269.467067] ? vrf_xmit+0x7f1/0x827 [vrf] [ 269.467067] ? ip_output+0xa4/0xdb [ 269.467067] __asan_load4+0x6b/0x6d [ 269.467067] vrf_xmit+0x7f1/0x827 [vrf] ... Which corresponds to the skb access after xmit handling. Fix by saving skb->len and using the saved value to update stats. Fixes: 193125dbd8eb2 ("net: Introduce VRF device driver") Signed-off-by: David Ahern Signed-off-by: David S. Miller Signed-off-by: Greg Kroah-Hartman

net: vrf: do not allow table id 0

2017-01-15T12:41:36Z

[ Upstream commit 24c63bbc18e25d5d8439422aa5fd2d66390b88eb ] Frank reported that vrf devices can be created with a table id of 0. This breaks many of the run time table id checks and should not be allowed. Detect this condition at create time and fail with EINVAL. Fixes: 193125dbd8eb ("net: Introduce VRF device driver") Reported-by: Frank Kellermann Signed-off-by: David Ahern Signed-off-by: David S. Miller Signed-off-by: Greg Kroah-Hartman

net: ipv4: Fix multipath selection with vrf

2017-01-15T12:41:36Z

[ Upstream commit 7a18c5b9fb31a999afc62b0e60978aa896fc89e9 ] fib_select_path does not call fib_select_multipath if oif is set in the flow struct. For VRF use cases oif is always set, so multipath route selection is bypassed. Use the FLOWI_FLAG_SKIP_NH_OIF to skip the oif check similar to what is done in fib_table_lookup. Add saddr and proto to the flow struct for the fib lookup done by the VRF driver to better match hash computation for a flow. Fixes: 613d09b30f8b ("net: Use VRF device index for lookups on TX") Signed-off-by: David Ahern Signed-off-by: David S. Miller Signed-off-by: Greg Kroah-Hartman

net: vrf: Drop conntrack data after pass through VRF device on Tx

2017-01-15T12:41:34Z

[ Upstream commit eb63ecc1706b3e094d0f57438b6c2067cfc299f2 ] Locally originated traffic in a VRF fails in the presence of a POSTROUTING rule. For example, $ iptables -t nat -A POSTROUTING -s 11.1.1.0/24 -j MASQUERADE $ ping -I red -c1 11.1.1.3 ping: Warning: source address might be selected on device other than red. PING 11.1.1.3 (11.1.1.3) from 11.1.1.2 red: 56(84) bytes of data. ping: sendmsg: Operation not permitted Worse, the above causes random corruption resulting in a panic in random places (I have not seen a consistent backtrace). Call nf_reset to drop the conntrack info following the pass through the VRF device. The nf_reset is needed on Tx but not Rx because of the order in which NF_HOOK's are hit: on Rx the VRF device is after the real ingress device and on Tx it is is before the real egress device. Connection tracking should be tied to the real egress device and not the VRF device. Fixes: 8f58336d3f78a ("net: Add ethernet header for pass through VRF device") Fixes: 35402e3136634 ("net: Add IPv6 support to VRF device") Signed-off-by: David Ahern Signed-off-by: David S. Miller Signed-off-by: Greg Kroah-Hartman

net: vrf: Remove direct access to skb->data

2016-04-20T06:41:57Z

[ Upstream commit 65c38aa653c14df49e19faad74bd375f36e61c57 ] Nik pointed that the VRF driver should be using skb_header_pointer instead of accessing skb->data and bits beyond directly which can be garbage. Fixes: 35402e313663 ("net: Add IPv6 support to VRF device") Cc: Nikolay Aleksandrov Signed-off-by: David Ahern Signed-off-by: Nikolay Aleksandrov Signed-off-by: David S. Miller Signed-off-by: Greg Kroah-Hartman

net: Propagate lookup failure in l3mdev_get_saddr to caller

2016-01-05T03:58:30Z

Commands run in a vrf context are not failing as expected on a route lookup: root@kenny:~# ip ro ls table vrf-red unreachable default root@kenny:~# ping -I vrf-red -c1 -w1 10.100.1.254 ping: Warning: source address might be selected on device other than vrf-red. PING 10.100.1.254 (10.100.1.254) from 0.0.0.0 vrf-red: 56(84) bytes of data. --- 10.100.1.254 ping statistics --- 2 packets transmitted, 0 received, 100% packet loss, time 999ms Since the vrf table does not have a route for 10.100.1.254 the ping should have failed. The saddr lookup causes a full VRF table lookup. Propogating a lookup failure to the user allows the command to fail as expected: root@kenny:~# ping -I vrf-red -c1 -w1 10.100.1.254 connect: No route to host Signed-off-by: David Ahern Signed-off-by: David S. Miller

vrf: fix double free and memory corruption on register_netdevice failure

2015-11-23T22:52:46Z

When vrf's ->newlink is called, if register_netdevice() fails then it does free_netdev(), but that's also done by rtnl_newlink() so a second free happens and memory gets corrupted, to reproduce execute the following line a couple of times (1 - 5 usually is enough): $ for i in `seq 1 5`; do ip link add vrf: type vrf table 1; done; This works because we fail in register_netdevice() because of the wrong name "vrf:". And here's a trace of one crash: [ 28.792157] ------------[ cut here ]------------ [ 28.792407] kernel BUG at fs/namei.c:246! [ 28.792608] invalid opcode: 0000 [#1] SMP [ 28.793240] Modules linked in: vrf nfsd auth_rpcgss oid_registry nfs_acl nfs lockd grace sunrpc crct10dif_pclmul crc32_pclmul crc32c_intel qxl drm_kms_helper ttm drm aesni_intel aes_x86_64 psmouse glue_helper lrw evdev gf128mul i2c_piix4 ablk_helper cryptd ppdev parport_pc parport serio_raw pcspkr virtio_balloon virtio_console i2c_core acpi_cpufreq button 9pnet_virtio 9p 9pnet fscache ipv6 autofs4 ext4 crc16 mbcache jbd2 virtio_blk virtio_net sg sr_mod cdrom ata_generic ehci_pci uhci_hcd ehci_hcd e1000 usbcore usb_common ata_piix libata virtio_pci virtio_ring virtio scsi_mod floppy [ 28.796016] CPU: 0 PID: 1148 Comm: ld-linux-x86-64 Not tainted 4.4.0-rc1+ #24 [ 28.796016] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.8.1-20150318_183358- 04/01/2014 [ 28.796016] task: ffff8800352561c0 ti: ffff88003592c000 task.ti: ffff88003592c000 [ 28.796016] RIP: 0010:[] [] putname+0x43/0x60 [ 28.796016] RSP: 0018:ffff88003592fe88 EFLAGS: 00010246 [ 28.796016] RAX: 0000000000000000 RBX: ffff8800352561c0 RCX: 0000000000000001 [ 28.796016] RDX: 0000000000000000 RSI: 0000000000000000 RDI: ffff88003784f000 [ 28.796016] RBP: ffff88003592ff08 R08: 0000000000000001 R09: 0000000000000000 [ 28.796016] R10: 0000000000000000 R11: 0000000000000001 R12: 0000000000000000 [ 28.796016] R13: 000000000000047c R14: ffff88003784f000 R15: ffff8800358c4a00 [ 28.796016] FS: 0000000000000000(0000) GS:ffff88003fc00000(0000) knlGS:0000000000000000 [ 28.796016] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [ 28.796016] CR2: 00007ffd583bc2d9 CR3: 0000000035a99000 CR4: 00000000000406f0 [ 28.796016] Stack: [ 28.796016] ffffffff8121045d ffffffff812102d3 ffff8800352561c0 ffff880035a91660 [ 28.796016] ffff8800008a9880 0000000000000000 ffffffff81a49940 00ffffff81218684 [ 28.796016] ffff8800352561c0 000000000000047c 0000000000000000 ffff880035b36d80 [ 28.796016] Call Trace: [ 28.796016] [] ? do_execveat_common.isra.34+0x74d/0x930 [ 28.796016] [] ? do_execveat_common.isra.34+0x5c3/0x930 [ 28.796016] [] do_execve+0x2c/0x30 [ 28.796016] [] call_usermodehelper_exec_async+0xf0/0x140 [ 28.796016] [] ? umh_complete+0x40/0x40 [ 28.796016] [] ret_from_fork+0x3f/0x70 [ 28.796016] Code: 48 8d 47 1c 48 89 e5 53 48 8b 37 48 89 fb 48 39 c6 74 1a 48 8b 3d 7e e9 8f 00 e8 49 fa fc ff 48 89 df e8 f1 01 fd ff 5b 5d f3 c3 <0f> 0b 48 89 fe 48 8b 3d 61 e9 8f 00 e8 2c fa fc ff 5b 5d eb e9 [ 28.796016] RIP [] putname+0x43/0x60 [ 28.796016] RSP Fixes: 193125dbd8eb ("net: Introduce VRF device driver") Signed-off-by: Nikolay Aleksandrov Acked-by: David Ahern Signed-off-by: David S. Miller