From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mail-oo2-f9.google.com (mail-oo2-f9.google.com [74.125.231.137]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 9FCEB274B4A for ; Wed, 2 Sep 2026 03:41:42 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=74.125.231.137 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1788320504; cv=none; b=NoCmNHlTbhu9x721G6lE0f7I2aElq/AStgPL5a502NgXau+WjxhfXfz3UYgviMfsHgmjhlSWj1EVOPaeahXxc/+19IVWGXV1Hc57QL7vsehgTv1bm5AVXT1b8ib+m4PqXFKBBDj8N7uKp/pu+PfitWjrz9nsC75vJPZRV4FHP7I= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1788320504; c=relaxed/simple; bh=pjoTA2Nr2VnrZDfw8norahjrz+TaPFTdXgMCkoIIWMQ=; h=MIME-Version:Date:Message-ID:Subject:From:To:Content-Type; b=JirgO3kBqBxzIWnTmJHDaiEEpKnhx+LdKf8PPxRGSauIFoCaKxrZyaCY8lLYJfxyzKllamQfnOJdiZ717swqzvYG7ERUV61S1P+EN9lWFtXnbwfXlGyppQXFd3by1ioCl0+JE537ghkQEO8J/Glsox0wMfdLoKE+uTIZs6CFZlQ= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=fail (p=none dis=none) header.from=syzkaller.appspotmail.com; spf=pass smtp.mailfrom=M3KW2WVRGUFZ5GODRSRYTGD7.apphosting.bounces.google.com; arc=none smtp.client-ip=74.125.231.137 Authentication-Results: smtp.subspace.kernel.org; dmarc=fail (p=none dis=none) header.from=syzkaller.appspotmail.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=M3KW2WVRGUFZ5GODRSRYTGD7.apphosting.bounces.google.com Received: by mail-oo2-f9.google.com with SMTP id 006d021491bc7-6b136fad4b3so155935eaf.0 for ; Tue, 01 Sep 2026 20:41:42 -0700 (PDT) X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20251104; t=1788320501; x=1788925301; h=content-type:to:from:subject:message-id:date:mime-version :x-gm-message-state:from:to:cc:subject:date:message-id:reply-to :content-type; bh=WknVe6YbEwHTjQ8SnS3LNO11L5BkxkkKwGa2maUHawk=; b=FcPeR5a3IqLIZZXM4hjWFEJk3JA+s5ol/QjY/9pyPV7NJLIcjUe0ah8EzMd/3mC3r1 BHB5y5EI3bAUKtUf6J7XLx88HmlI8uZCrK9gRxfgWIanxSPs0SsYHokPatcYL0n7fY/q BO9ii410zlH/vTpdLiB5nPDITHav9/zfIVlgR/7qMalq9PlShljfW6oHJnmpotnjA42j Rew0rR9J3CySgpUVie2i+vAyqy38cc65QWb4MV84Bya0ygOt6fFB3SUJ2JBcjTJfk94x kZ5IkeldlfqdgwH/le7y06l8mxtcLGndndZueiroamh6UAHD7B0eHviOmRfvuxncK2T6 NsYg== X-Forwarded-Encrypted: i=1; AHgh+RodpUAYI5kU7bUTv+7DC/DeLNZnHVMyDMvjC9RfHa80s8nckcfLioEgbGXFf9kZ9F/8eN3C9jX1ISaLNXQ=@vger.kernel.org X-Gm-Message-State: AFuF++n/4JO8PPgW138HrHJ+U6Z4aWuqqBXxdqgq3Me/CQ0wCkaEO5TV 8tec0QjCemewGKQMTLVYUuaCuw7/sDcKExkkEznuTHxFUnCn+K0ngVTuNuMkJHfn1EGTahIPjSO r6twQOemCvtSnaemh26htJJZ+j3y2eG3VCkRLSIMI5+nbMyRriFKJVu2VMko= Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 X-Received: by 2002:a05:6820:c84:b0:6b1:6136:956a with SMTP id 006d021491bc7-6b47fc2dfa3mr1688847eaf.15.1788320501447; Tue, 01 Sep 2026 20:41:41 -0700 (PDT) Date: Tue, 01 Sep 2026 20:41:41 -0700 X-Google-Appengine-App-Id: s~syzkaller X-Google-Appengine-App-Id-Alias: syzkaller Message-ID: <6a979af5.e163c37b.143a1.0004.GAE@google.com> Subject: [syzbot] [f2fs?] general protection fault in new_curseg From: syzbot To: chao@kernel.org, jaegeuk@kernel.org, linux-f2fs-devel@lists.sourceforge.net, linux-kernel@vger.kernel.org, syzkaller-bugs@googlegroups.com Content-Type: text/plain; charset="UTF-8" Hello, syzbot found the following issue on: HEAD commit: 89a312991dc6 Merge tag 'cifs-fixes-7.3-rc2' of https://git.. git tree: upstream console output: https://syzkaller.appspot.com/x/log.txt?x=1075e779580000 kernel config: https://syzkaller.appspot.com/x/.config?x=e909ffe6b35dddb7 dashboard link: https://syzkaller.appspot.com/bug?extid=ae5b8eb92ed40411ce16 compiler: Debian clang version 22.1.8 (++20260613092233+e80beda6e255-1~exp1~20260613092250.77), Debian LLD 22.1.8 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-89a31299.raw.xz vmlinux: https://storage.googleapis.com/syzbot-assets/114a4744ab8e/vmlinux-89a31299.xz kernel image: https://storage.googleapis.com/syzbot-assets/c65021627f2c/bzImage-89a31299.xz IMPORTANT: if you fix the issue, please add the following tag to the commit: Reported-by: syzbot+ae5b8eb92ed40411ce16@syzkaller.appspotmail.com Oops: general protection fault, probably for non-canonical address 0xdffffc000000000c: 0000 [#1] SMP KASAN NOPTI KASAN: null-ptr-deref in range [0x0000000000000060-0x0000000000000067] CPU: 0 UID: 0 PID: 12 Comm: kworker/u4:0 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 Workqueue: writeback wb_workfn (flush-7:0) RIP: 0010:f2fs_dev_is_alloc_blocked fs/f2fs/segment.h:956 [inline] RIP: 0010:get_new_segment fs/f2fs/segment.c:2964 [inline] RIP: 0010:new_curseg+0x1134/0x3580 fs/f2fs/segment.c:3110 Code: e8 21 ab ce fd 48 8b 7c 24 30 48 8b 07 49 6b cf 70 4c 8d 34 08 49 83 c6 61 4c 89 f0 48 c1 e8 03 48 b9 00 00 00 00 00 fc ff df <0f> b6 04 08 84 c0 0f 85 73 11 00 00 41 80 3e 00 0f 84 e6 00 00 00 RSP: 0018:ffffc9000025e628 EFLAGS: 00010206 RAX: 000000000000000c RBX: 0000000000008000 RCX: dffffc0000000000 RDX: 0000000000000000 RSI: 0000000000008000 RDI: ffff888012125a88 RBP: 0000000000000000 R08: 0000000000000003 R09: 0000000000000004 R10: dffffc0000000000 R11: fffff5200004bcb4 R12: ffff888052be0000 R13: 0000000000000004 R14: 0000000000000061 R15: 0000000000000000 FS: 0000000000000000(0000) GS:ffff88808c2cf000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000200001000000 CR3: 000000004fe72000 CR4: 0000000000352ef0 Call Trace: f2fs_allocate_data_block+0x229c/0x43c0 fs/f2fs/segment.c:3979 do_write_page+0x13f/0x880 fs/f2fs/segment.c:4099 f2fs_outplace_write_data+0x11a/0x220 fs/f2fs/segment.c:4175 f2fs_write_compressed_pages fs/f2fs/compress.c:1403 [inline] f2fs_write_multi_pages+0x43bb/0x6370 fs/f2fs/compress.c:1602 f2fs_write_cache_pages fs/f2fs/data.c:3351 [inline] __f2fs_write_data_pages fs/f2fs/data.c:3603 [inline] f2fs_write_data_pages+0x19bb/0x36f0 fs/f2fs/data.c:3641 do_writepages+0x338/0x560 mm/page-writeback.c:2560 __writeback_single_inode+0x136/0x1220 fs/fs-writeback.c:1788 writeback_sb_inodes+0x9de/0x1b00 fs/fs-writeback.c:2099 __writeback_inodes_wb+0x114/0x240 fs/fs-writeback.c:2175 wb_writeback+0x42f/0xad0 fs/fs-writeback.c:2286 wb_check_start_all fs/fs-writeback.c:2412 [inline] wb_do_writeback fs/fs-writeback.c:2459 [inline] wb_workfn+0x980/0x10f0 fs/fs-writeback.c:2497 process_one_work kernel/workqueue.c:3396 [inline] process_scheduled_works+0xc3d/0x1630 kernel/workqueue.c:3479 worker_thread+0xa47/0xfb0 kernel/workqueue.c:3560 kthread+0x38b/0x480 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 Modules linked in: ---[ end trace 0000000000000000 ]--- RIP: 0010:f2fs_dev_is_alloc_blocked fs/f2fs/segment.h:956 [inline] RIP: 0010:get_new_segment fs/f2fs/segment.c:2964 [inline] RIP: 0010:new_curseg+0x1134/0x3580 fs/f2fs/segment.c:3110 Code: e8 21 ab ce fd 48 8b 7c 24 30 48 8b 07 49 6b cf 70 4c 8d 34 08 49 83 c6 61 4c 89 f0 48 c1 e8 03 48 b9 00 00 00 00 00 fc ff df <0f> b6 04 08 84 c0 0f 85 73 11 00 00 41 80 3e 00 0f 84 e6 00 00 00 RSP: 0018:ffffc9000025e628 EFLAGS: 00010206 RAX: 000000000000000c RBX: 0000000000008000 RCX: dffffc0000000000 RDX: 0000000000000000 RSI: 0000000000008000 RDI: ffff888012125a88 RBP: 0000000000000000 R08: 0000000000000003 R09: 0000000000000004 R10: dffffc0000000000 R11: fffff5200004bcb4 R12: ffff888052be0000 R13: 0000000000000004 R14: 0000000000000061 R15: 0000000000000000 FS: 0000000000000000(0000) GS:ffff88808c2cf000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000200001000000 CR3: 000000004fe72000 CR4: 0000000000352ef0 ---------------- Code disassembly (best guess): 0: e8 21 ab ce fd call 0xfdceab26 5: 48 8b 7c 24 30 mov 0x30(%rsp),%rdi a: 48 8b 07 mov (%rdi),%rax d: 49 6b cf 70 imul $0x70,%r15,%rcx 11: 4c 8d 34 08 lea (%rax,%rcx,1),%r14 15: 49 83 c6 61 add $0x61,%r14 19: 4c 89 f0 mov %r14,%rax 1c: 48 c1 e8 03 shr $0x3,%rax 20: 48 b9 00 00 00 00 00 movabs $0xdffffc0000000000,%rcx 27: fc ff df * 2a: 0f b6 04 08 movzbl (%rax,%rcx,1),%eax <-- trapping instruction 2e: 84 c0 test %al,%al 30: 0f 85 73 11 00 00 jne 0x11a9 36: 41 80 3e 00 cmpb $0x0,(%r14) 3a: 0f 84 e6 00 00 00 je 0x126 --- This report is generated by a bot. It may contain errors. See https://goo.gl/tpsmEJ for more information about syzbot. syzbot engineers can be reached at syzkaller@googlegroups.com. syzbot will keep track of this issue. See: https://goo.gl/tpsmEJ#status for how to communicate with syzbot. If the report is already addressed, let syzbot know by replying with: #syz fix: exact-commit-title If you want to overwrite report's subsystems, reply with: #syz set subsystems: new-subsystem (See the list of subsystem names on the web dashboard) If the report is a duplicate of another one, reply with: #syz dup: exact-subject-of-another-report If you want to undo deduplication, reply with: #syz undup