[moderation] [can?] general protection fault in can_rx_unregister (2)

[syzbot]

Hello,

syzbot found the following issue on:

HEAD commit: f5459048c38a Merge tag 'i2c-for-7.0-final' of git://git.ke..
git tree: upstream
console output: https://syzkaller.appspot.com/x/log.txt?x=16231036580000
kernel config: https://syzkaller.appspot.com/x/.config?x=5a3e5e8c17cc174e
dashboard link: https://syzkaller.appspot.com/bug?extid=0b0900adc47a4f6f9f9a
compiler: gcc (Debian 14.2.0-19) 14.2.0, GNU ld (GNU Binutils for Debian) 2.44
CC: [linu...@vger.kernel.org linux-...@vger.kernel.org m...@pengutronix.de sock...@hartkopp.net]

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

Downloadable assets:
disk image (non-bootable): https://storage.googleapis.com/syzbot-assets/d900f083ada3/non_bootable_disk-f5459048.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/2e8650caf6ce/vmlinux-f5459048.xz
kernel image: https://storage.googleapis.com/syzbot-assets/6cf7182d4101/bzImage-f5459048.xz

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+0b0900...@syzkaller.appspotmail.com

Oops: general protection fault, probably for non-canonical address 0xdffffc000000000b: 0000 [#1] SMP KASAN NOPTI
KASAN: null-ptr-deref in range [0x0000000000000058-0x000000000000005f]
CPU: 0 UID: 0 PID: 6472 Comm: syz.1.124 Not tainted syzkaller #0 PREEMPT(full)
Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.3-debian-1.16.3-2 04/01/2014
RIP: 0010:can_rx_unregister+0x250/0x6d0 net/can/af_can.c:537
Code: 54 24 18 48 8d 84 24 b8 00 00 00 48 8d 74 24 78 48 8d 78 b0 e8 d1 ee ff ff 48 ba 00 00 00 00 00 fc ff df 48 89 c1 48 c1 e9 03 <80> 3c 11 00 0f 85 4f 04 00 00 48 8b 18 44 8b 64 24 68 44 8b 7c 24
RSP: 0018:ffffc900037bfb80 EFLAGS: 00010202
RAX: 0000000000000058 RBX: 0000000000000000 RCX: 000000000000000b
RDX: dffffc0000000000 RSI: ffffffff8a801db9 RDI: ffff888032190000
RBP: 0000000000000000 R08: 0000000000000005 R09: 00000000c00007ff
R10: 00000000c00007ff R11: 0000000000000000 R12: ffff888022db0578
R13: ffff888028a64000 R14: 1ffff920006f7f77 R15: 00000000c00007ff
FS: 0000555577445500(0000) GS:ffff8880d6338000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007fb862b4da08 CR3: 0000000064937000 CR4: 0000000000352ef0
Call Trace:
<TASK>
isotp_release+0x899/0xaf0 net/can/isotp.c:1231
__sock_release+0xb3/0x260 net/socket.c:662
sock_close+0x1c/0x30 net/socket.c:1455
__fput+0x3ff/0xb40 fs/file_table.c:469
task_work_run+0x150/0x240 kernel/task_work.c:233
resume_user_mode_work include/linux/resume_user_mode.h:50 [inline]
__exit_to_user_mode_loop kernel/entry/common.c:67 [inline]
exit_to_user_mode_loop+0x100/0x4a0 kernel/entry/common.c:98
__exit_to_user_mode_prepare include/linux/irq-entry-common.h:226 [inline]
syscall_exit_to_user_mode_prepare include/linux/irq-entry-common.h:256 [inline]
syscall_exit_to_user_mode include/linux/entry-common.h:325 [inline]
do_syscall_64+0x67c/0xf80 arch/x86/entry/syscall_64.c:100
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7fd0f599c819
Code: ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 44 00 00 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 e8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007ffc8a8669c8 EFLAGS: 00000246 ORIG_RAX: 00000000000001b4
RAX: 0000000000000000 RBX: 00007ffc8a866ab0 RCX: 00007fd0f599c819
RDX: 0000000000000000 RSI: 000000000000001e RDI: 0000000000000003
RBP: 0000000000011d11 R08: 0000000000000001 R09: 0000000000000000
R10: 0000001b2ea20000 R11: 0000000000000246 R12: 00007ffc8a866af0
R13: 00007fd0f5c15fac R14: 0000000000011d8f R15: 00007fd0f5c15fa0
</TASK>
Modules linked in:
---[ end trace 0000000000000000 ]---
RIP: 0010:can_rx_unregister+0x250/0x6d0 net/can/af_can.c:537
Code: 54 24 18 48 8d 84 24 b8 00 00 00 48 8d 74 24 78 48 8d 78 b0 e8 d1 ee ff ff 48 ba 00 00 00 00 00 fc ff df 48 89 c1 48 c1 e9 03 <80> 3c 11 00 0f 85 4f 04 00 00 48 8b 18 44 8b 64 24 68 44 8b 7c 24
RSP: 0018:ffffc900037bfb80 EFLAGS: 00010202
RAX: 0000000000000058 RBX: 0000000000000000 RCX: 000000000000000b
RDX: dffffc0000000000 RSI: ffffffff8a801db9 RDI: ffff888032190000
RBP: 0000000000000000 R08: 0000000000000005 R09: 00000000c00007ff
R10: 00000000c00007ff R11: 0000000000000000 R12: ffff888022db0578
R13: ffff888028a64000 R14: 1ffff920006f7f77 R15: 00000000c00007ff
FS: 0000555577445500(0000) GS:ffff8880d6338000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007fb862b4da08 CR3: 0000000064937000 CR4: 0000000000352ef0
----------------
Code disassembly (best guess):
0: 54 push %rsp
1: 24 18 and $0x18,%al
3: 48 8d 84 24 b8 00 00 lea 0xb8(%rsp),%rax
a: 00
b: 48 8d 74 24 78 lea 0x78(%rsp),%rsi
10: 48 8d 78 b0 lea -0x50(%rax),%rdi
14: e8 d1 ee ff ff call 0xffffeeea
19: 48 ba 00 00 00 00 00 movabs $0xdffffc0000000000,%rdx
20: fc ff df
23: 48 89 c1 mov %rax,%rcx
26: 48 c1 e9 03 shr $0x3,%rcx
* 2a: 80 3c 11 00 cmpb $0x0,(%rcx,%rdx,1) <-- trapping instruction
2e: 0f 85 4f 04 00 00 jne 0x483
34: 48 8b 18 mov (%rax),%rbx
37: 44 8b 64 24 68 mov 0x68(%rsp),%r12d
3c: 44 rex.R
3d: 8b .byte 0x8b
3e: 7c 24 jl 0x64


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