general protection fault in batadv_iv_send_outstanding_bat_ogm_packet

[syzbot]

Hello,

syzbot found the following issue on:

HEAD commit: 13af6c74 Linux 4.19.136
git tree: linux-4.19.y
console output: https://syzkaller.appspot.com/x/log.txt?x=1293540a900000
kernel config: https://syzkaller.appspot.com/x/.config?x=5b7578d3b5457a49
dashboard link: https://syzkaller.appspot.com/bug?extid=67c47b15450f54413571
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+67c47b...@syzkaller.appspotmail.com

IPVS: ftp: loaded support on port[0] = 21
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: 0 PID: 23 Comm: kworker/u4:1 Not tainted 4.19.136-syzkaller #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_aggr_packet net/batman-adv/bat_iv_ogm.c:511 [inline]
RIP: 0010:batadv_iv_ogm_send_to_if net/batman-adv/bat_iv_ogm.c:538 [inline]
RIP: 0010:batadv_iv_ogm_emit net/batman-adv/bat_iv_ogm.c:604 [inline]
RIP: 0010:batadv_iv_send_outstanding_bat_ogm_packet+0x408/0x7a0 net/batman-adv/bat_iv_ogm.c:1857
Code: 24 3b 00 48 89 44 24 30 48 89 cd 4c 89 74 24 20 e8 4d 4f 4c fa 48 8d 7d 16 48 b9 00 00 00 00 00 fc ff df 48 89 f8 48 c1 e8 03 <0f> b6 14 08 48 89 f8 83 e0 07 83 c0 01 38 d0 7c 08 84 d2 0f 85 4d
RSP: 0018:ffff8880a9507cc8 EFLAGS: 00010203
RAX: 0000000000000002 RBX: ffff8880529dc0c8 RCX: dffffc0000000000
RDX: 0000000000000000 RSI: ffffffff871d5ff3 RDI: 0000000000000016
RBP: 0000000000000000 R08: 0000000000000000 R09: 0000000000000017
R10: 0000000000000005 R11: 0000000000000000 R12: 0000000000000018
R13: 0000000000000000 R14: ffff8880529dc080 R15: 000000000000003c
FS: 0000000000000000(0000) GS:ffff8880ae600000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007ffd31140e37 CR3: 00000001feed9000 CR4: 00000000001426f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
process_one_work+0x864/0x1570 kernel/workqueue.c:2155
worker_thread+0x64c/0x1130 kernel/workqueue.c:2298
kthread+0x30b/0x410 kernel/kthread.c:246
ret_from_fork+0x24/0x30 arch/x86/entry/entry_64.S:415
Modules linked in:
---[ end trace ffb0647477651b7c ]---
RIP: 0010:batadv_iv_ogm_aggr_packet net/batman-adv/bat_iv_ogm.c:511 [inline]
RIP: 0010:batadv_iv_ogm_send_to_if net/batman-adv/bat_iv_ogm.c:538 [inline]
RIP: 0010:batadv_iv_ogm_emit net/batman-adv/bat_iv_ogm.c:604 [inline]
RIP: 0010:batadv_iv_send_outstanding_bat_ogm_packet+0x408/0x7a0 net/batman-adv/bat_iv_ogm.c:1857
Code: 24 3b 00 48 89 44 24 30 48 89 cd 4c 89 74 24 20 e8 4d 4f 4c fa 48 8d 7d 16 48 b9 00 00 00 00 00 fc ff df 48 89 f8 48 c1 e8 03 <0f> b6 14 08 48 89 f8 83 e0 07 83 c0 01 38 d0 7c 08 84 d2 0f 85 4d
RSP: 0018:ffff8880a9507cc8 EFLAGS: 00010203
RAX: 0000000000000002 RBX: ffff8880529dc0c8 RCX: dffffc0000000000
RDX: 0000000000000000 RSI: ffffffff871d5ff3 RDI: 0000000000000016
RBP: 0000000000000000 R08: 0000000000000000 R09: 0000000000000017
R10: 0000000000000005 R11: 0000000000000000 R12: 0000000000000018
R13: 0000000000000000 R14: ffff8880529dc080 R15: 000000000000003c
FS: 0000000000000000(0000) GS:ffff8880ae600000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007ffd31140e37 CR3: 00000001feed9000 CR4: 00000000001426f0
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.