general protection fault in udp_tunnel_notify_del_rx_port

[syzbot]

Hello,

syzbot found the following issue on:

HEAD commit: 88825726 Merge tag 'drm-fixes-2020-07-17-1' of git://anong..
git tree: upstream
console output: https://syzkaller.appspot.com/x/log.txt?x=143518bb100000
kernel config: https://syzkaller.appspot.com/x/.config?x=a160d1053fc89af5
dashboard link: https://syzkaller.appspot.com/bug?extid=a41f2e0a3a2dad7febb0
compiler: gcc (GCC) 10.1.0-syz 20200507

Unfortunately, I don't have any reproducer for this issue yet.

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+a41f2e...@syzkaller.appspotmail.com

general protection fault, probably for non-canonical address 0xdffffc000000003b: 0000 [#1] PREEMPT SMP KASAN
KASAN: null-ptr-deref in range [0x00000000000001d8-0x00000000000001df]
CPU: 0 PID: 22020 Comm: syz-executor.2 Not tainted 5.8.0-rc5-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
RIP: 0010:udp_tunnel_notify_del_rx_port+0x1e8/0x3f0 net/ipv4/udp_tunnel.c:161
Code: 01 00 00 48 89 f8 48 c1 e8 03 80 3c 28 00 0f 85 e0 01 00 00 4c 8b a3 e0 01 00 00 49 8d bc 24 d8 01 00 00 48 89 f8 48 c1 e8 03 <80> 3c 28 00 0f 85 b6 01 00 00 4d 8b a4 24 d8 01 00 00 4d 85 e4 74
RSP: 0018:ffffc900165ef810 EFLAGS: 00010202
RAX: 000000000000003b RBX: ffff888000102000 RCX: ffffc9000d7a2000
RDX: 0000000000040000 RSI: ffffffff86c7005a RDI: 00000000000001d8
RBP: dffffc0000000000 R08: 0000000000000000 R09: ffffffff8c599a27
R10: 0000000000000000 R11: 0000000000000000 R12: 0000000000000000
R13: ffff88805b9c0210 R14: ffffc900165ef838 R15: ffff88809dffa268
FS: 00007f890f5fa700(0000) GS:ffff8880ae600000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000000000000004 CR3: 00000000614b3000 CR4: 00000000001426f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
__geneve_sock_release.part.0+0x13d/0x1e0 drivers/net/geneve.c:610
__geneve_sock_release drivers/net/geneve.c:631 [inline]
geneve_sock_release+0x1bf/0x290 drivers/net/geneve.c:629
geneve_stop+0x198/0x200 drivers/net/geneve.c:720
__dev_close_many+0x1b3/0x2e0 net/core/dev.c:1599
__dev_close net/core/dev.c:1611 [inline]
__dev_change_flags+0x272/0x660 net/core/dev.c:8276
dev_change_flags+0x8a/0x160 net/core/dev.c:8349
devinet_ioctl+0x14fd/0x1ca0 net/ipv4/devinet.c:1143
inet_ioctl+0x1ea/0x330 net/ipv4/af_inet.c:964
sock_do_ioctl+0xcb/0x2d0 net/socket.c:1048
sock_ioctl+0x3b8/0x730 net/socket.c:1199
vfs_ioctl fs/ioctl.c:48 [inline]
ksys_ioctl+0x11a/0x180 fs/ioctl.c:753
__do_sys_ioctl fs/ioctl.c:762 [inline]
__se_sys_ioctl fs/ioctl.c:760 [inline]
__x64_sys_ioctl+0x6f/0xb0 fs/ioctl.c:760
do_syscall_64+0x60/0xe0 arch/x86/entry/common.c:384
entry_SYSCALL_64_after_hwframe+0x44/0xa9
RIP: 0033:0x45c1d9
Code: Bad RIP value.
RSP: 002b:00007f890f5f9c78 EFLAGS: 00000246 ORIG_RAX: 0000000000000010
RAX: ffffffffffffffda RBX: 0000000000013e00 RCX: 000000000045c1d9
RDX: 0000000020000000 RSI: 0000000000008914 RDI: 0000000000000003
RBP: 000000000078bf40 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 000000000078bf0c
R13: 0000000000c9fb6f R14: 00007f890f5fa9c0 R15: 000000000078bf0c
Modules linked in:
---[ end trace 82520c6676e9d8d2 ]---
RIP: 0010:udp_tunnel_notify_del_rx_port+0x1e8/0x3f0 net/ipv4/udp_tunnel.c:161
Code: 01 00 00 48 89 f8 48 c1 e8 03 80 3c 28 00 0f 85 e0 01 00 00 4c 8b a3 e0 01 00 00 49 8d bc 24 d8 01 00 00 48 89 f8 48 c1 e8 03 <80> 3c 28 00 0f 85 b6 01 00 00 4d 8b a4 24 d8 01 00 00 4d 85 e4 74
RSP: 0018:ffffc900165ef810 EFLAGS: 00010202
RAX: 000000000000003b RBX: ffff888000102000 RCX: ffffc9000d7a2000
RDX: 0000000000040000 RSI: ffffffff86c7005a RDI: 00000000000001d8
RBP: dffffc0000000000 R08: 0000000000000000 R09: ffffffff8c599a27
R10: 0000000000000000 R11: 0000000000000000 R12: 0000000000000000
R13: ffff88805b9c0210 R14: ffffc900165ef838 R15: ffff88809dffa268
FS: 00007f890f5fa700(0000) GS:ffff8880ae600000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f890f575db8 CR3: 00000000614b3000 CR4: 00000000001426f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400


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[Jakub Kicinski]

On Wed, 22 Jul 2020 06:27:17 -0700 syzbot wrote:
> Hello,
>
> syzbot found the following issue on:
>
> HEAD commit: 88825726 Merge tag 'drm-fixes-2020-07-17-1' of git://anong..
> git tree: upstream
> console output: https://syzkaller.appspot.com/x/log.txt?x=143518bb100000
> kernel config: https://syzkaller.appspot.com/x/.config?x=a160d1053fc89af5
> dashboard link: https://syzkaller.appspot.com/bug?extid=a41f2e0a3a2dad7febb0
> compiler: gcc (GCC) 10.1.0-syz 20200507

FWIW I had a look and it appears that this is not really related to
udp_tunnel_notify_del_rx_port() in any way. Seems a netdev or its
ops get corrupted and udp_tunnel_notify_del_rx_port() just runs into
that.

[syzbot]

Auto-closing this bug as obsolete.
Crashes did not happen for a while, no reproducer and no activity.