| Message ID | c59f4adcdd1296ee37cc6bca4d927b8c79158909.1668727939.git.pabeni@redhat.com (mailing list archive) |
|---|---|
| State | Changes Requested |
| Delegated to: | Netdev Maintainers |
| Headers | show |
| Series | veth: a couple of fixes | expand |
diff --git a/drivers/net/veth.c b/drivers/net/veth.c index 2a4592780141..1384134f7100 100644 --- a/drivers/net/veth.c +++ b/drivers/net/veth.c @@ -1381,7 +1381,8 @@ static int veth_close(struct net_device *dev) if (!veth_gro_requested(peer) && !peer_priv->_xdp_prog) veth_napi_del(peer); } - } else if (veth_gro_requested(dev) || (peer && peer_priv->_xdp_prog)) { + } else if ((veth_gro_requested(dev) || (peer && peer_priv->_xdp_prog)) && + rtnl_dereference(priv->rq[0].napi)) { veth_napi_del(dev); }
syzkaller reports a list corruption at veth close time: kernel BUG at lib/list_debug.c:56! invalid opcode: 0000 [#1] PREEMPT SMP KASAN CPU: 1 PID: 4247 Comm: syz-executor.4 Not tainted 6.1.0-rc4-syzkaller-01115-g68d268d08931 #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/26/2022 RIP: 0010:__list_del_entry_valid.cold+0x37/0x72 lib/list_debug.c:56 Code: e8 d2 62 f0 ff 0f 0b 48 89 ee 48 c7 c7 80 10 a8 8a e8 c1 62 f0 ff 0f 0b 4c 89 e2 48 89 ee 48 c7 c7 40 11 a8 8a e8 ad 62 f0 ff <0f> 0b 48 89 ee 48 c7 c7 20 10 a8 8a e8 9c 62 f0 ff 0f 0b 4c 89 ea RSP: 0018:ffffc9000a116ed0 EFLAGS: 00010282 RAX: 000000000000004e RBX: 0000000000000000 RCX: 0000000000000000 RDX: 0000000000040000 RSI: ffffffff8165772c RDI: fffff52001422dcc RBP: ffff88804eace160 R08: 000000000000004e R09: 0000000000000000 R10: 0000000080000000 R11: 0000000000000000 R12: dead000000000122 R13: ffff88804eab6050 R14: ffff88804eace000 R15: ffff88804eace000 FS: 00007fa8ab74e700(0000) GS:ffff8880b9b00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 000000002040f030 CR3: 000000007efb8000 CR4: 00000000003506e0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: <TASK> __list_del_entry include/linux/list.h:134 [inline] list_del_rcu include/linux/rculist.h:157 [inline] __netif_napi_del.part.0+0x118/0x530 net/core/dev.c:6458 __netif_napi_del+0x40/0x50 net/core/dev.c:6454 veth_napi_del_range+0xcd/0x560 drivers/net/veth.c:1041 veth_napi_del drivers/net/veth.c:1055 [inline] veth_close+0x164/0x500 drivers/net/veth.c:1385 __dev_close_many+0x1b6/0x2e0 net/core/dev.c:1501 __dev_close net/core/dev.c:1513 [inline] __dev_change_flags+0x2ce/0x750 net/core/dev.c:8528 dev_change_flags+0x97/0x170 net/core/dev.c:8602 do_setlink+0x9f1/0x3bb0 net/core/rtnetlink.c:2827 rtnl_group_changelink net/core/rtnetlink.c:3344 [inline] __rtnl_newlink+0xb90/0x1840 net/core/rtnetlink.c:3600 rtnl_newlink+0x68/0xa0 net/core/rtnetlink.c:3637 rtnetlink_rcv_msg+0x43e/0xca0 net/core/rtnetlink.c:6141 netlink_rcv_skb+0x165/0x440 net/netlink/af_netlink.c:2564 netlink_unicast_kernel net/netlink/af_netlink.c:1330 [inline] netlink_unicast+0x547/0x7f0 net/netlink/af_netlink.c:1356 netlink_sendmsg+0x91b/0xe10 net/netlink/af_netlink.c:1932 sock_sendmsg_nosec net/socket.c:714 [inline] sock_sendmsg+0xd3/0x120 net/socket.c:734 ____sys_sendmsg+0x712/0x8c0 net/socket.c:2476 ___sys_sendmsg+0x110/0x1b0 net/socket.c:2530 __sys_sendmsg+0xf7/0x1c0 net/socket.c:2559 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x39/0xb0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x63/0xcd RIP: 0033:0x7fa8aaa8b639 Code: ff ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 00 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 b8 ff ff ff f7 d8 64 89 01 48 RSP: 002b:00007fa8ab74e168 EFLAGS: 00000246 ORIG_RAX: 000000000000002e RAX: ffffffffffffffda RBX: 00007fa8aababf80 RCX: 00007fa8aaa8b639 RDX: 0000000000000000 RSI: 0000000020000140 RDI: 0000000000000003 RBP: 00007fa8aaae6ae9 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007ffe720d839f R14: 00007fa8ab74e300 R15: 0000000000022000 </TASK> The issue can actually reproduced with: ip link add type veth ip link set dev veth0 up ip link set dev veth1 up ip link set dev veth0 xdp object <obj> ip link set dev veth0 down ip link set dev veth1 down The veth1 napi instances are deleted first when veth0 goes down, and when veth1 is shut down, veth_close() tries again to delete them, causing the oops. This patch addresses the issue explicitly checking that the napi instances are enabled before deleting them. Fixes: 2e0de6366ac1 ("veth: Avoid drop packets when xdp_redirect performs") Reported-by: syzbot+0cffe54ffe58ab9c059b@syzkaller.appspotmail.com Signed-off-by: Paolo Abeni <pabeni@redhat.com> --- drivers/net/veth.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-)