Re: kernel BUG at net/rxrpc/local_object.c:LINE!

syzbot
2019-08-18T18:47:08Z

syzbot has found a reproducer for the following crash on:

HEAD commit: 0c3d3d64 Add linux-next specific files for 20190816
git tree: linux-next
console output: https://syzkaller.appspot.com/x/log.txt?x=108b58f2600000
kernel config: https://syzkaller.appspot.com/x/.config?x=dffdf1e146f941f4
dashboard link: https://syzkaller.appspot.com/bug?extid=1e0edc4b8b7494c28450
compiler: gcc (GCC) 9.0.0 20181231 (experimental)
syz repro: https://syzkaller.appspot.com/x/repro.syz?x=13feb73c600000
C reproducer: https://syzkaller.appspot.com/x/repro.c?x=127088f2600000

The bug was bisected to:

commit 46894a13599a977ac35411b536fb3e0b2feefa95
Author: David Howells <dhowells@redhat.com>
Date: Thu Oct 4 08:32:28 2018 +0000

rxrpc: Use IPv4 addresses throught the IPv6

bisection log: https://syzkaller.appspot.com/x/bisect.txt?x=152fabe3a00000
final crash: https://syzkaller.appspot.com/x/report.txt?x=172fabe3a00000
console output: https://syzkaller.appspot.com/x/log.txt?x=132fabe3a00000

IMPORTANT: if you fix the bug, please add the following tag to the commit:
Reported-by: syzbot+1e0edc4b8b7494c28450@syzkaller.appspotmail.com
Fixes: 46894a13599a ("rxrpc: Use IPv4 addresses throught the IPv6")

rxrpc: Assertion failed
------------[ cut here ]------------
kernel BUG at net/rxrpc/local_object.c:433!
invalid opcode: 0000 [#1] PREEMPT SMP KASAN
CPU: 0 PID: 12 Comm: kworker/0:1 Not tainted 5.3.0-rc4-next-20190816 #67
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS
Google 01/01/2011
Workqueue: krxrpcd rxrpc_local_processor
RIP: 0010:rxrpc_local_destroyer net/rxrpc/local_object.c:433 [inline]
RIP: 0010:rxrpc_local_processor.cold+0x24/0x29 net/rxrpc/local_object.c:466
Code: df a1 bc fa 0f 0b e8 c4 2b d3 fa 48 c7 c7 e0 24 5b 88 e8 cc a1 bc fa
0f 0b e8 b1 2b d3 fa 48 c7 c7 e0 24 5b 88 e8 b9 a1 bc fa <0f> 0b 90 90 90
55 48 89 e5 41 57 49 89 ff 41 56 41 55 41 54 53 48
RSP: 0018:ffff8880a98d7ce8 EFLAGS: 00010282
RAX: 0000000000000017 RBX: ffff88808c90a978 RCX: 0000000000000000
RDX: 0000000000000000 RSI: ffffffff815bb906 RDI: ffffed101531af8f
RBP: ffff8880a98d7d30 R08: 0000000000000017 R09: ffffed1015d060d9
R10: ffffed1015d060d8 R11: ffff8880ae8306c7 R12: ffff88808c90a208
R13: ffff88808dc48648 R14: ffff88808c90a940 R15: ffff8880929faa00
FS: 0000000000000000(0000) GS:ffff8880ae800000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000000000049f2b0 CR3: 0000000008e6d000 CR4: 00000000001406f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
process_one_work+0x9af/0x1740 kernel/workqueue.c:2269
worker_thread+0x98/0xe40 kernel/workqueue.c:2415
kthread+0x361/0x430 kernel/kthread.c:255
ret_from_fork+0x24/0x30 arch/x86/entry/entry_64.S:352
Modules linked in:
---[ end trace c65e44ef4b16c854 ]---
RIP: 0010:rxrpc_local_destroyer net/rxrpc/local_object.c:433 [inline]
RIP: 0010:rxrpc_local_processor.cold+0x24/0x29 net/rxrpc/local_object.c:466
Code: df a1 bc fa 0f 0b e8 c4 2b d3 fa 48 c7 c7 e0 24 5b 88 e8 cc a1 bc fa
0f 0b e8 b1 2b d3 fa 48 c7 c7 e0 24 5b 88 e8 b9 a1 bc fa <0f> 0b 90 90 90
55 48 89 e5 41 57 49 89 ff 41 56 41 55 41 54 53 48
RSP: 0018:ffff8880a98d7ce8 EFLAGS: 00010282
RAX: 0000000000000017 RBX: ffff88808c90a978 RCX: 0000000000000000
RDX: 0000000000000000 RSI: ffffffff815bb906 RDI: ffffed101531af8f
RBP: ffff8880a98d7d30 R08: 0000000000000017 R09: ffffed1015d060d9
R10: ffffed1015d060d8 R11: ffff8880ae8306c7 R12: ffff88808c90a208
R13: ffff88808dc48648 R14: ffff88808c90a940 R15: ffff8880929faa00
FS: 0000000000000000(0000) GS:ffff8880ae800000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: ffffffffff600400 CR3: 000000009b982000 CR4: 00000000001406f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400