[moderation] [net?] general protection fault in arp_create

[syzbot]

Hello,

syzbot found the following issue on:

HEAD commit: 3cdb45594619 Merge tag 's390-6.9-4' of git://git.kernel.or..
git tree: upstream
console output: https://syzkaller.appspot.com/x/log.txt?x=1606f4bb180000
kernel config: https://syzkaller.appspot.com/x/.config?x=f47e5e015c177e57
dashboard link: https://syzkaller.appspot.com/bug?extid=e853a4ab28f206e63cad
compiler: Debian clang version 15.0.6, GNU ld (GNU Binutils for Debian) 2.40
CC: [da...@davemloft.net dsa...@kernel.org edum...@google.com ku...@kernel.org linux-...@vger.kernel.org net...@vger.kernel.org pab...@redhat.com]

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

Downloadable assets:
disk image: https://storage.googleapis.com/syzbot-assets/4befd8e98bed/disk-3cdb4559.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/efc09f95602f/vmlinux-3cdb4559.xz
kernel image: https://storage.googleapis.com/syzbot-assets/29a54be03694/bzImage-3cdb4559.xz

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+e853a4...@syzkaller.appspotmail.com

general protection fault, probably for non-canonical address 0xdffffc0000000016: 0000 [#1] PREEMPT SMP KASAN PTI
KASAN: null-ptr-deref in range [0x00000000000000b0-0x00000000000000b7]
CPU: 0 PID: 50 Comm: kworker/u8:3 Not tainted 6.9.0-rc4-syzkaller-00173-g3cdb45594619 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 03/27/2024
Workqueue: bat_events batadv_bla_periodic_work
RIP: 0010:arp_create+0x46/0x920 net/ipv4/arp.c:553
Code: 49 89 ce 89 54 24 3c 89 74 24 30 89 fb 49 bd 00 00 00 00 00 fc ff df e8 a8 5e ab f7 49 8d be b4 00 00 00 48 89 f8 48 c1 e8 03 <42> 0f b6 04 28 84 c0 0f 85 ef 05 00 00 45 0f b7 a6 b4 00 00 00 49
RSP: 0018:ffffc90000ba7910 EFLAGS: 00010203
RAX: 0000000000000016 RBX: 0000000000000002 RCX: ffff888017eada00
RDX: 0000000000000000 RSI: 0000000000000806 RDI: 00000000000000b4
RBP: ffffc90000ba7a90 R08: 0000000000000000 R09: 0000000000000000
R10: dffffc0000000000 R11: fffff52000174f44 R12: ffff88802f92c018
R13: dffffc0000000000 R14: 0000000000000000 R15: 0000000000000002
FS: 0000000000000000(0000) GS:ffff8880b9400000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f03f3081440 CR3: 000000001ed00000 CR4: 00000000003506f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
<TASK>
batadv_bla_send_claim+0x16f/0xe80 net/batman-adv/bridge_loop_avoidance.c:361
batadv_bla_send_announce net/batman-adv/bridge_loop_avoidance.c:675 [inline]
batadv_bla_periodic_work+0x5dc/0xaf0 net/batman-adv/bridge_loop_avoidance.c:1481
process_one_work kernel/workqueue.c:3254 [inline]
process_scheduled_works+0xa10/0x17c0 kernel/workqueue.c:3335
worker_thread+0x86d/0xd70 kernel/workqueue.c:3416
kthread+0x2f0/0x390 kernel/kthread.c:388
ret_from_fork+0x4b/0x80 arch/x86/kernel/process.c:147
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244
</TASK>
Modules linked in:
---[ end trace 0000000000000000 ]---
RIP: 0010:arp_create+0x46/0x920 net/ipv4/arp.c:553
Code: 49 89 ce 89 54 24 3c 89 74 24 30 89 fb 49 bd 00 00 00 00 00 fc ff df e8 a8 5e ab f7 49 8d be b4 00 00 00 48 89 f8 48 c1 e8 03 <42> 0f b6 04 28 84 c0 0f 85 ef 05 00 00 45 0f b7 a6 b4 00 00 00 49
RSP: 0018:ffffc90000ba7910 EFLAGS: 00010203
RAX: 0000000000000016 RBX: 0000000000000002 RCX: ffff888017eada00
RDX: 0000000000000000 RSI: 0000000000000806 RDI: 00000000000000b4
RBP: ffffc90000ba7a90 R08: 0000000000000000 R09: 0000000000000000
R10: dffffc0000000000 R11: fffff52000174f44 R12: ffff88802f92c018
R13: dffffc0000000000 R14: 0000000000000000 R15: 0000000000000002
FS: 0000000000000000(0000) GS:ffff8880b9400000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f03f3081440 CR3: 000000001ed00000 CR4: 00000000003506f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
----------------
Code disassembly (best guess):
0: 49 89 ce mov %rcx,%r14
3: 89 54 24 3c mov %edx,0x3c(%rsp)
7: 89 74 24 30 mov %esi,0x30(%rsp)
b: 89 fb mov %edi,%ebx
d: 49 bd 00 00 00 00 00 movabs $0xdffffc0000000000,%r13
14: fc ff df
17: e8 a8 5e ab f7 call 0xf7ab5ec4
1c: 49 8d be b4 00 00 00 lea 0xb4(%r14),%rdi
23: 48 89 f8 mov %rdi,%rax
26: 48 c1 e8 03 shr $0x3,%rax
* 2a: 42 0f b6 04 28 movzbl (%rax,%r13,1),%eax <-- trapping instruction
2f: 84 c0 test %al,%al
31: 0f 85 ef 05 00 00 jne 0x626
37: 45 0f b7 a6 b4 00 00 movzwl 0xb4(%r14),%r12d
3e: 00
3f: 49 rex.WB


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