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

From: syzbot
Date: Thu Jun 27 2019 - 22:47:09 EST

Hello,

syzbot found the following crash on:

HEAD commit: 249155c2 Merge branch 'parisc-5.2-4' of git://git.kernel.o..
git tree: upstream
console output: https://syzkaller.appspot.com/x/log.txt?x=14fabe45a00000
kernel config: https://syzkaller.appspot.com/x/.config?x=e7c31a94f66cc0aa
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=13e2738da00000

The bug was bisected to:

commit 46894a13599a977ac35411b536fb3e0b2feefa95
Author: David Howells <dhowells@xxxxxxxxxx>
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@xxxxxxxxxxxxxxxxxxxxxxxxx
Fixes: 46894a13599a ("rxrpc: Use IPv4 addresses throught the IPv6")

rxrpc: Assertion failed
------------[ cut here ]------------
kernel BUG at net/rxrpc/local_object.c:468!
invalid opcode: 0000 [#1] PREEMPT SMP KASAN
CPU: 1 PID: 16 Comm: ksoftirqd/1 Not tainted 5.2.0-rc6+ #60
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
RIP: 0010:rxrpc_local_rcu net/rxrpc/local_object.c:468 [inline]
RIP: 0010:rxrpc_local_rcu.cold+0x11/0x13 net/rxrpc/local_object.c:462
Code: 83 eb 20 e9 74 ff ff ff e8 58 aa 2d fb eb cc 4c 89 ef e8 6e aa 2d fb eb e2 e8 d7 fd f4 fa 48 c7 c7 20 8c 15 88 e8 6f 03 df fa <0f> 0b e8 c4 fd f4 fa 48 c7 c7 20 8c 15 88 e8 5c 03 df fa 0f 0b e8
RSP: 0018:ffff8880a9917c98 EFLAGS: 00010286
RAX: 0000000000000017 RBX: 0000000000000001 RCX: 0000000000000000
RDX: 0000000000000000 RSI: ffffffff815ad926 RDI: ffffed1015322f85
RBP: ffff8880a9917ca8 R08: 0000000000000017 R09: ffffed1015d260a1
R10: ffffed1015d260a0 R11: ffff8880ae930507 R12: ffff888099033b40
R13: ffff888099033b40 R14: ffffffff867b8f10 R15: ffff8880a9917d28
FS: 0000000000000000(0000) GS:ffff8880ae900000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f380ebda000 CR3: 000000007ad50000 CR4: 00000000001406e0
Call Trace:
__rcu_reclaim kernel/rcu/rcu.h:222 [inline]
rcu_do_batch kernel/rcu/tree.c:2092 [inline]
invoke_rcu_callbacks kernel/rcu/tree.c:2310 [inline]
rcu_core+0xba5/0x1500 kernel/rcu/tree.c:2291
__do_softirq+0x25c/0x94c kernel/softirq.c:292
run_ksoftirqd kernel/softirq.c:603 [inline]
run_ksoftirqd+0x8e/0x110 kernel/softirq.c:595
smpboot_thread_fn+0x6a3/0xa30 kernel/smpboot.c:165
kthread+0x354/0x420 kernel/kthread.c:255
ret_from_fork+0x24/0x30 arch/x86/entry/entry_64.S:352
Modules linked in:
---[ end trace 0e784d6285151217 ]---
RIP: 0010:rxrpc_local_rcu net/rxrpc/local_object.c:468 [inline]
RIP: 0010:rxrpc_local_rcu.cold+0x11/0x13 net/rxrpc/local_object.c:462
Code: 83 eb 20 e9 74 ff ff ff e8 58 aa 2d fb eb cc 4c 89 ef e8 6e aa 2d fb eb e2 e8 d7 fd f4 fa 48 c7 c7 20 8c 15 88 e8 6f 03 df fa <0f> 0b e8 c4 fd f4 fa 48 c7 c7 20 8c 15 88 e8 5c 03 df fa 0f 0b e8
RSP: 0018:ffff8880a9917c98 EFLAGS: 00010286
RAX: 0000000000000017 RBX: 0000000000000001 RCX: 0000000000000000
RDX: 0000000000000000 RSI: ffffffff815ad926 RDI: ffffed1015322f85
RBP: ffff8880a9917ca8 R08: 0000000000000017 R09: ffffed1015d260a1
R10: ffffed1015d260a0 R11: ffff8880ae930507 R12: ffff888099033b40
R13: ffff888099033b40 R14: ffffffff867b8f10 R15: ffff8880a9917d28
FS: 0000000000000000(0000) GS:ffff8880ae900000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f380ebda000 CR3: 000000007ad50000 CR4: 00000000001406e0


---
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