From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mail-oa1-f78.google.com (mail-oa1-f78.google.com [209.85.160.78]) (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 1C8AC3E5591 for ; Tue, 14 Apr 2026 13:58:30 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=209.85.160.78 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1776175112; cv=none; b=CCOZXuOTGwSMF+bjz9jI6ofFP66mXJ4GSmUyPM0uXr4FGeyC3H/goAttMR+iHTbbi9ZUizEeMQZ2g1XQ83GCysXk+bxkIUSjAW5Q6LFkYuLOmAiWCgIVnRZVrAZ1BgPab281paOlPW/GU0i5RLAhdIUuvHr9niYyMQBX2XaQyxg= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1776175112; c=relaxed/simple; bh=J4D67UWjuFui1G+Wxv//O7qqWMvG1YuiXR7YExP6Rlk=; h=MIME-Version:Date:Message-ID:Subject:From:To:Content-Type; b=GyX2KAuSrXYF7gd6bJj+AcpAaQWfClxylHTeY5Ji5H0iGfjLwILfAQaiSSPoCeS9g2RIHk/pcWOLHo+l0JDcUSElUW3N4ZlDa2ivNnxRaMlMYvmyC+EqLWk4bj547nuMylqSJRHYwOqqoN5s6PPVwEnK1hvdmoN8TYhevJEMxUc= 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=209.85.160.78 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-oa1-f78.google.com with SMTP id 586e51a60fabf-415e1ea16b4so10591798fac.1 for ; Tue, 14 Apr 2026 06:58:30 -0700 (PDT) X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20251104; t=1776175110; x=1776779910; h=to:from:subject:message-id:date:mime-version:x-gm-message-state :from:to:cc:subject:date:message-id:reply-to; bh=hBgdAsL//GQnTapAXF/VlCVSr0qK85PQANpDue0Mnv0=; b=g3LD+wxQ/ErTZNV5GDClZpDhhDoppzTM6ZEcmKg7VaysAk0SgNeVc/Ug1eojV41Dmw 69JsMtl4vQ/9pA/8l1Q+9Ee2g5JYuf4eKrxBPbRXZNTL000gSvBFkMjocTBDXD6reAzB mSdTSWekZxudRVKHSH6/3ZG9jTshyEqiPMtgIn+n5+8tBNuDpElK8aBggUqsQskCmcEx VO0S1KdFq0C0v2ISieEv4hGwjbN4FAevIyuEvfVlZwFewIhiT2nYU7OjFCjUze3WVYxo y8KfqmmNZnYN8iz+NzUft4ig1Vgs1e7MOlAFk78AnuzHv95a4EQ6q81HEp1gtkTnqKXi 6o4g== X-Forwarded-Encrypted: i=1; AFNElJ/HRegkdrVPVyuq8X+n26/TVnxgo5YVjGAmiM0fLo7QLZorKxdAR5CUTUqq0BE0HPmKxVhNikuYihY2h3c=@vger.kernel.org X-Gm-Message-State: AOJu0YxOLPACc3tb3B7iuqbCuSHEQQEnJqMCfXAHkxgDs94WLX2KjF9z QhOD2dmbsLu3m/5lU/m4It+bWOeC4bYyiJdR0gWl1oLDEHdHRt+kFqZUSd4J0t5jgrYSjRAgE8n x7AFRDCdtqOsv5br4bVNuYXyLIW0rnoJp/3KpLPh0VdXo5ukyl7u4zHCDrxk= Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 X-Received: by 2002:a4a:ef03:0:b0:67b:b0bd:8bd2 with SMTP id 006d021491bc7-68be89e6708mr5870736eaf.59.1776175110028; Tue, 14 Apr 2026 06:58:30 -0700 (PDT) Date: Tue, 14 Apr 2026 06:58:30 -0700 X-Google-Appengine-App-Id: s~syzkaller X-Google-Appengine-App-Id-Alias: syzkaller Message-ID: <69de4806.a00a0220.475f0.0043.GAE@google.com> Subject: [syzbot] [netfs?] general protection fault in netfs_put_subrequest From: syzbot To: dhowells@redhat.com, linux-fsdevel@vger.kernel.org, linux-kernel@vger.kernel.org, netfs@lists.linux.dev, pc@manguebit.org, syzkaller-bugs@googlegroups.com Content-Type: text/plain; charset="UTF-8" Hello, syzbot found the following issue on: HEAD commit: 9a9c8ce300cd Merge tag 'kbuild-fixes-7.0-4' of git://git.k.. git tree: upstream console output: https://syzkaller.appspot.com/x/log.txt?x=142de106580000 kernel config: https://syzkaller.appspot.com/x/.config?x=5a3e5e8c17cc174e dashboard link: https://syzkaller.appspot.com/bug?extid=a0788ffdca16ee21c493 compiler: gcc (Debian 14.2.0-19) 14.2.0, GNU ld (GNU Binutils for Debian) 2.44 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-9a9c8ce3.raw.xz vmlinux: https://storage.googleapis.com/syzbot-assets/073107a6c46a/vmlinux-9a9c8ce3.xz kernel image: https://storage.googleapis.com/syzbot-assets/f6457493483c/bzImage-9a9c8ce3.xz IMPORTANT: if you fix the issue, please add the following tag to the commit: Reported-by: syzbot+a0788ffdca16ee21c493@syzkaller.appspotmail.com Oops: general protection fault, probably for non-canonical address 0xdffffc0000000055: 0000 [#1] SMP KASAN NOPTI KASAN: null-ptr-deref in range [0x00000000000002a8-0x00000000000002af] CPU: 1 UID: 0 PID: 1247 Comm: kworker/u32:10 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: events_unbound netfs_unbuffered_write_async RIP: 0010:netfs_put_subrequest+0x88/0x4e0 fs/netfs/objects.c:248 Code: df 48 c1 ea 03 80 3c 02 00 0f 85 fa 03 00 00 48 b8 00 00 00 00 00 fc ff df 48 8b 2b 48 8d bd ac 02 00 00 48 89 fa 48 c1 ea 03 <0f> b6 14 02 48 89 f8 83 e0 07 83 c0 03 38 d0 7c 08 84 d2 0f 85 96 RSP: 0018:ffffc9000619fa48 EFLAGS: 00010207 RAX: dffffc0000000000 RBX: ffff88804679adc0 RCX: 0000000000000000 RDX: 0000000000000055 RSI: 0000000000000008 RDI: 00000000000002ac RBP: 0000000000000000 R08: 1ffff110055b509b R09: 0000000000000000 R10: 0000000000000001 R11: 0000000000000000 R12: 0000000000000007 R13: 0000000000000001 R14: 0000000000000002 R15: ffff88804679ae10 FS: 0000000000000000(0000) GS:ffff8880d6438000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000000000000000 CR3: 000000002b072000 CR4: 0000000000352ef0 Call Trace: netfs_clear_subrequests+0x158/0x260 fs/netfs/objects.c:106 netfs_unbuffered_write_done fs/netfs/direct_write.c:59 [inline] netfs_unbuffered_write+0x13ac/0x2260 fs/netfs/direct_write.c:202 netfs_unbuffered_write_async+0x19/0x30 fs/netfs/direct_write.c:211 process_one_work+0xa23/0x19a0 kernel/workqueue.c:3276 process_scheduled_works kernel/workqueue.c:3359 [inline] worker_thread+0x5ef/0xe50 kernel/workqueue.c:3440 kthread+0x370/0x450 kernel/kthread.c:436 ret_from_fork+0x754/0xd80 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:netfs_put_subrequest+0x88/0x4e0 fs/netfs/objects.c:248 Code: df 48 c1 ea 03 80 3c 02 00 0f 85 fa 03 00 00 48 b8 00 00 00 00 00 fc ff df 48 8b 2b 48 8d bd ac 02 00 00 48 89 fa 48 c1 ea 03 <0f> b6 14 02 48 89 f8 83 e0 07 83 c0 03 38 d0 7c 08 84 d2 0f 85 96 RSP: 0018:ffffc9000619fa48 EFLAGS: 00010207 RAX: dffffc0000000000 RBX: ffff88804679adc0 RCX: 0000000000000000 RDX: 0000000000000055 RSI: 0000000000000008 RDI: 00000000000002ac RBP: 0000000000000000 R08: 1ffff110055b509b R09: 0000000000000000 R10: 0000000000000001 R11: 0000000000000000 R12: 0000000000000007 R13: 0000000000000001 R14: 0000000000000002 R15: ffff88804679ae10 FS: 0000000000000000(0000) GS:ffff8880d6438000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000000000000000 CR3: 0000000031877000 CR4: 0000000000352ef0 ---------------- Code disassembly (best guess), 1 bytes skipped: 0: 48 c1 ea 03 shr $0x3,%rdx 4: 80 3c 02 00 cmpb $0x0,(%rdx,%rax,1) 8: 0f 85 fa 03 00 00 jne 0x408 e: 48 b8 00 00 00 00 00 movabs $0xdffffc0000000000,%rax 15: fc ff df 18: 48 8b 2b mov (%rbx),%rbp 1b: 48 8d bd ac 02 00 00 lea 0x2ac(%rbp),%rdi 22: 48 89 fa mov %rdi,%rdx 25: 48 c1 ea 03 shr $0x3,%rdx * 29: 0f b6 14 02 movzbl (%rdx,%rax,1),%edx <-- trapping instruction 2d: 48 89 f8 mov %rdi,%rax 30: 83 e0 07 and $0x7,%eax 33: 83 c0 03 add $0x3,%eax 36: 38 d0 cmp %dl,%al 38: 7c 08 jl 0x42 3a: 84 d2 test %dl,%dl 3c: 0f .byte 0xf 3d: 85 .byte 0x85 3e: 96 xchg %eax,%esi --- 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