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general protection fault in ovs_vport_add

Status: fixed on 2019/12/13 00:31
Subsystems: openvswitch
[Documentation on labels]
Fix commit: 9077f052abd5 net: propagate errors correctly in register_netdevice()
First crash: 1722d, last: 1713d
Cause bisection: introduced by (bisect log) :
commit b401170f6d9cd4270e0159d9b016f4ccb06caa85
Author: J. Bruce Fields <bfields@redhat.com>
Date: Thu May 16 18:24:40 2019 +0000

  nfsd: don't call nfsd_reply_cache_shutdown twice

Crash: KASAN: use-after-free Read in internal_dev_create (log)
Repro: C syz .config
  

Sample crash report:
RBP: 0000000000000000 R08: 0000000000000002 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: ffffffffffffffff
R13: 0000000000000004 R14: 0000000000000000 R15: 0000000000000000
kasan: CONFIG_KASAN_INLINE enabled
kasan: GPF could be caused by NULL-ptr deref or user memory access
general protection fault: 0000 [#1] PREEMPT SMP KASAN
CPU: 1 PID: 8760 Comm: syz-executor839 Not tainted 5.3.0+ #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
RIP: 0010:ovs_vport_add+0x185/0x500 net/openvswitch/vport.c:205
Code: 89 c6 e8 3e b6 3a fa 49 81 fc 00 f0 ff ff 0f 87 6d 02 00 00 e8 8c b4 3a fa 4c 89 e2 48 b8 00 00 00 00 00 fc ff df 48 c1 ea 03 <80> 3c 02 00 0f 85 d3 02 00 00 49 8d 7c 24 08 49 8b 34 24 48 b8 00
RSP: 0018:ffff88808fe5f4e0 EFLAGS: 00010247
RAX: dffffc0000000000 RBX: ffffffff89be8820 RCX: ffffffff87385162
RDX: 0000000000000000 RSI: ffffffff87385174 RDI: 0000000000000007
RBP: ffff88808fe5f510 R08: ffff8880933c6600 R09: fffffbfff14ee13c
R10: fffffbfff14ee13b R11: ffffffff8a7709df R12: 0000000000000004
R13: ffffffff89be8850 R14: ffff88808fe5f5e0 R15: 0000000000000002
FS:  0000000001d71880(0000) GS:ffff8880ae900000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000000020000280 CR3: 0000000096e4c000 CR4: 00000000001406e0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 new_vport+0x1b/0x1d0 net/openvswitch/datapath.c:194
 ovs_dp_cmd_new+0x5e5/0xe30 net/openvswitch/datapath.c:1644
 genl_family_rcv_msg+0x74b/0xf90 net/netlink/genetlink.c:629
 genl_rcv_msg+0xca/0x170 net/netlink/genetlink.c:654
 netlink_rcv_skb+0x177/0x450 net/netlink/af_netlink.c:2477
 genl_rcv+0x29/0x40 net/netlink/genetlink.c:665
 netlink_unicast_kernel net/netlink/af_netlink.c:1302 [inline]
 netlink_unicast+0x531/0x710 net/netlink/af_netlink.c:1328
 netlink_sendmsg+0x8a5/0xd60 net/netlink/af_netlink.c:1917
 sock_sendmsg_nosec net/socket.c:637 [inline]
 sock_sendmsg+0xd7/0x130 net/socket.c:657
 ___sys_sendmsg+0x803/0x920 net/socket.c:2311
 __sys_sendmsg+0x105/0x1d0 net/socket.c:2356
 __do_sys_sendmsg net/socket.c:2365 [inline]
 __se_sys_sendmsg net/socket.c:2363 [inline]
 __x64_sys_sendmsg+0x78/0xb0 net/socket.c:2363
 do_syscall_64+0xfa/0x760 arch/x86/entry/common.c:290
 entry_SYSCALL_64_after_hwframe+0x49/0xbe
RIP: 0033:0x442359
Code: e8 9c 07 03 00 48 83 c4 18 c3 0f 1f 80 00 00 00 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 0f 83 3b 0a fc ff c3 66 2e 0f 1f 84 00 00 00 00
RSP: 002b:00007ffea3f13d58 EFLAGS: 00000246 ORIG_RAX: 000000000000002e
RAX: ffffffffffffffda RBX: 0000000000000003 RCX: 0000000000442359
RDX: 0000000000000000 RSI: 0000000020000280 RDI: 0000000000000003
RBP: 0000000000000000 R08: 0000000000000002 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: ffffffffffffffff
R13: 0000000000000004 R14: 0000000000000000 R15: 0000000000000000
Modules linked in:
---[ end trace 0a1a5ab3bc5eebe1 ]---
RIP: 0010:ovs_vport_add+0x185/0x500 net/openvswitch/vport.c:205
Code: 89 c6 e8 3e b6 3a fa 49 81 fc 00 f0 ff ff 0f 87 6d 02 00 00 e8 8c b4 3a fa 4c 89 e2 48 b8 00 00 00 00 00 fc ff df 48 c1 ea 03 <80> 3c 02 00 0f 85 d3 02 00 00 49 8d 7c 24 08 49 8b 34 24 48 b8 00
RSP: 0018:ffff88808fe5f4e0 EFLAGS: 00010247
RAX: dffffc0000000000 RBX: ffffffff89be8820 RCX: ffffffff87385162
RDX: 0000000000000000 RSI: ffffffff87385174 RDI: 0000000000000007
RBP: ffff88808fe5f510 R08: ffff8880933c6600 R09: fffffbfff14ee13c
R10: fffffbfff14ee13b R11: ffffffff8a7709df R12: 0000000000000004
R13: ffffffff89be8850 R14: ffff88808fe5f5e0 R15: 0000000000000002
FS:  0000000001d71880(0000) GS:ffff8880ae900000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000000020000280 CR3: 0000000096e4c000 CR4: 00000000001406e0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400

Crashes (5):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2019/10/03 13:21 bpf-next 03bd4773d898 fc17ba49 .config console log report syz C ci-upstream-bpf-next-kasan-gce
2019/10/12 06:25 bpf-next 409017847d20 426631dd .config console log report ci-upstream-bpf-next-kasan-gce
2019/10/09 13:45 bpf-next f05c2001ecc9 312c6a5a .config console log report ci-upstream-bpf-next-kasan-gce
2019/10/04 23:30 bpf-next 4bbbf164f1a5 f3f7d9c8 .config console log report ci-upstream-bpf-next-kasan-gce
2019/10/03 12:43 bpf-next 03bd4773d898 fc17ba49 .config console log report ci-upstream-bpf-next-kasan-gce
* Struck through repros no longer work on HEAD.