Forwarded: Re: [syzbot] [f2fs?] kernel BUG in f2fs_write_end_io (2)

[syzbot <syzbot+4af46ee83100e99bce09@syzkaller.appspotmail.com>]

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Subject: Re: [syzbot] [f2fs?] kernel BUG in f2fs_write_end_io (2)
Author: chao@kernel.org

#syz test: https://git.kernel.org/pub/scm/linux/kernel/git/chao/linux.git bugfix/syzbot

On 5/14/26 20:19, syzbot wrote:
> Hello,
> 
> syzbot found the following issue on:
> 
> HEAD commit:    aa54b1d27fe0 rxrpc: Also unshare DATA/RESPONSE packets whe..
> git tree:       upstream
> console output: https://syzkaller.appspot.com/x/log.txt?x=14adabce580000
> kernel config:  https://syzkaller.appspot.com/x/.config?x=f2e8ebfec4636d32
> dashboard link: https://syzkaller.appspot.com/bug?extid=4af46ee83100e99bce09
> compiler:       Debian clang version 21.1.8 (++20251221033036+2078da43e25a-1~exp1~20251221153213.50), Debian LLD 21.1.8
> syz repro:      https://syzkaller.appspot.com/x/repro.syz?x=1643c3ce580000
> C reproducer:   https://syzkaller.appspot.com/x/repro.c?x=12adabce580000
> 
> Downloadable assets:
> disk image: https://storage.googleapis.com/syzbot-assets/418e3ed628cf/disk-aa54b1d2.raw.xz
> vmlinux: https://storage.googleapis.com/syzbot-assets/a35b53d0ab2f/vmlinux-aa54b1d2.xz
> kernel image: https://storage.googleapis.com/syzbot-assets/03c3fa0081b4/bzImage-aa54b1d2.xz
> mounted in repro #1: https://storage.googleapis.com/syzbot-assets/13e397c7f935/mount_0.gz
>    fsck result: failed (log: https://syzkaller.appspot.com/x/fsck.log?x=158fad06580000)
> mounted in repro #2: https://storage.googleapis.com/syzbot-assets/2f91edde40dc/mount_8.gz
> 
> IMPORTANT: if you fix the issue, please add the following tag to the commit:
> Reported-by: syzbot+4af46ee83100e99bce09@syzkaller.appspotmail.com
> 
> ------------[ cut here ]------------
> kernel BUG at fs/f2fs/data.c:388!
> Oops: invalid opcode: 0000 [#1] SMP KASAN PTI
> CPU: 1 UID: 0 PID: 31 Comm: ksoftirqd/1 Not tainted syzkaller #0 PREEMPT_{RT,(full)}
> Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 04/18/2026
> RIP: 0010:f2fs_write_end_io+0x16df/0x1740 fs/f2fs/data.c:388
> Code: 20 3c 9b 8b e8 12 0a f7 fc 90 0f 0b e8 0a cc 93 fd 48 8b 3c 24 48 c7 c6 20 3c 9b 8b e8 fa 09 f7 fc 90 0f 0b e8 f2 cb 93 fd 90 <0f> 0b e8 ea cb 93 fd 48 8b 3c 24 48 c7 c6 20 3c 9b 8b e8 da 09 f7
> RSP: 0018:ffffc90000a5fb18 EFLAGS: 00010246
> RAX: ffffffff8430aade RBX: ffffea0000d91c40 RCX: ffff88801d6b0000
> RDX: 0000000000000100 RSI: 0000000000000000 RDI: 0000000000000100
> RBP: dffffc0000000000 R08: 0000000000000000 R09: 0000000000000100
> R10: dffffc0000000000 R11: fffffbfff1f11dff R12: 0000000036471000
> R13: ffffea0000d91c80 R14: 000000000000000b R15: 0000000000000000
> FS:  0000000000000000(0000) GS:ffff888126276000(0000) knlGS:0000000000000000
> CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
> CR2: 00007eff6352cff8 CR3: 000000002caa2000 CR4: 00000000003526f0
> Call Trace:
>   <TASK>
>   blk_update_request+0x57e/0xe60 block/blk-mq.c:1016
>   blk_mq_end_request+0x3e/0x70 block/blk-mq.c:1178
>   blk_complete_reqs block/blk-mq.c:1253 [inline]
>   blk_done_softirq+0x10a/0x160 block/blk-mq.c:1258
>   handle_softirqs+0x1de/0x6d0 kernel/softirq.c:622
>   run_ksoftirqd+0x52/0x180 kernel/softirq.c:1076
>   smpboot_thread_fn+0x541/0xa50 kernel/smpboot.c:160
>   kthread+0x388/0x470 kernel/kthread.c:436
>   ret_from_fork+0x514/0xb70 arch/x86/kernel/process.c:158
>   ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245
>   </TASK>
> Modules linked in:
> ---[ end trace 0000000000000000 ]---
> RIP: 0010:f2fs_write_end_io+0x16df/0x1740 fs/f2fs/data.c:388
> Code: 20 3c 9b 8b e8 12 0a f7 fc 90 0f 0b e8 0a cc 93 fd 48 8b 3c 24 48 c7 c6 20 3c 9b 8b e8 fa 09 f7 fc 90 0f 0b e8 f2 cb 93 fd 90 <0f> 0b e8 ea cb 93 fd 48 8b 3c 24 48 c7 c6 20 3c 9b 8b e8 da 09 f7
> RSP: 0018:ffffc90000a5fb18 EFLAGS: 00010246
> RAX: ffffffff8430aade RBX: ffffea0000d91c40 RCX: ffff88801d6b0000
> RDX: 0000000000000100 RSI: 0000000000000000 RDI: 0000000000000100
> RBP: dffffc0000000000 R08: 0000000000000000 R09: 0000000000000100
> R10: dffffc0000000000 R11: fffffbfff1f11dff R12: 0000000036471000
> R13: ffffea0000d91c80 R14: 000000000000000b R15: 0000000000000000
> FS:  0000000000000000(0000) GS:ffff888126276000(0000) knlGS:0000000000000000
> CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
> CR2: 00007eff6352cff8 CR3: 000000002caa2000 CR4: 00000000003526f0
> 
> 
> ---
> This report is generated by a bot. It may contain errors.
> See https://goo.gl/tpsmEJ for more information about syzbot.
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> 
> syzbot will keep track of this issue. See:
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> 
> If the report is already addressed, let syzbot know by replying with:
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> 
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> 
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> 
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> 
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