general protection fault in batadv_iv_ogm_queue_add

[syzbot]

Hello,

syzbot found the following crash on:

HEAD commit: dafd6344 Linux 4.19.79
git tree: linux-4.19.y
console output: https://syzkaller.appspot.com/x/log.txt?x=17ca13c7600000
kernel config: https://syzkaller.appspot.com/x/.config?x=f825f73d8fea6b52
dashboard link: https://syzkaller.appspot.com/bug?extid=59b7dd207667c81b9481
compiler: gcc (GCC) 9.0.0 20181231 (experimental)

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

IMPORTANT: if you fix the bug, please add the following tag to the commit:
Reported-by: syzbot+59b7dd...@syzkaller.appspotmail.com

batman_adv: batadv0: Removing interface: veth11
batman_adv: batadv0: Removing interface: veth13
batman_adv: batadv0: Removing interface: veth15
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: 23 Comm: kworker/u4:1 Not tainted 4.19.79 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS
Google 01/01/2011
Workqueue: bat_events batadv_iv_send_outstanding_bat_ogm_packet
RIP: 0010:batadv_iv_ogm_queue_add+0x49/0x1120
net/batman-adv/bat_iv_ogm.c:791
Code: 48 89 75 b8 48 89 4d c0 4c 89 45 b0 44 89 4d d0 e8 cc 14 96 fa 48 8d
7b 03 48 b8 00 00 00 00 00 fc ff df 48 89 fa 48 c1 ea 03 <0f> b6 04 02 48
89 fa 83 e2 07 38 d0 7f 08 84 c0 0f 85 18 0d 00 00
RSP: 0018:ffff8880aa3a7b68 EFLAGS: 00010246
RAX: dffffc0000000000 RBX: 0000000000000000 RCX: ffff8880a4829780
RDX: 0000000000000000 RSI: ffffffff86d565b4 RDI: 0000000000000003
RBP: ffff8880aa3a7c00 R08: ffff8880a4829780 R09: 0000000000000001
R10: ffffed100b1414f7 R11: ffff888058a0a7bb R12: ffff888058a0a7b8
R13: 0000000100002128 R14: ffff8880a4829780 R15: 000000010000218e
FS: 0000000000000000(0000) GS:ffff8880ae900000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00000000010fd000 CR3: 00000000874ac000 CR4: 00000000001406e0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
batadv_iv_ogm_schedule+0x7dd/0xf10 net/batman-adv/bat_iv_ogm.c:979
batadv_iv_send_outstanding_bat_ogm_packet+0x590/0x740
net/batman-adv/bat_iv_ogm.c:1823
process_one_work+0x989/0x1750 kernel/workqueue.c:2153
worker_thread+0x98/0xe40 kernel/workqueue.c:2296
kthread+0x354/0x420 kernel/kthread.c:246
ret_from_fork+0x24/0x30 arch/x86/entry/entry_64.S:415
Modules linked in:
---[ end trace 4d7e6fdc23baff27 ]---
RIP: 0010:batadv_iv_ogm_queue_add+0x49/0x1120
net/batman-adv/bat_iv_ogm.c:791
Code: 48 89 75 b8 48 89 4d c0 4c 89 45 b0 44 89 4d d0 e8 cc 14 96 fa 48 8d
7b 03 48 b8 00 00 00 00 00 fc ff df 48 89 fa 48 c1 ea 03 <0f> b6 04 02 48
89 fa 83 e2 07 38 d0 7f 08 84 c0 0f 85 18 0d 00 00
RSP: 0018:ffff8880aa3a7b68 EFLAGS: 00010246
RAX: dffffc0000000000 RBX: 0000000000000000 RCX: ffff8880a4829780
RDX: 0000000000000000 RSI: ffffffff86d565b4 RDI: 0000000000000003
RBP: ffff8880aa3a7c00 R08: ffff8880a4829780 R09: 0000000000000001
R10: ffffed100b1414f7 R11: ffff888058a0a7bb R12: ffff888058a0a7b8
R13: 0000000100002128 R14: ffff8880a4829780 R15: 000000010000218e
FS: 0000000000000000(0000) GS:ffff8880ae800000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f8a028e8028 CR3: 00000000874ac000 CR4: 00000000001406f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400


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[syzbot]

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