From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mail-ot1-f79.google.com (mail-ot1-f79.google.com [209.85.210.79]) (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 9154038644D for ; Mon, 11 May 2026 07:29:30 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=209.85.210.79 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1778484572; cv=none; b=Ezs8aocBEb1eXSQHmn0fKJVyXP8OGrdTUlav26mQwVen/2yWdz/QR/192PUbKNABOTVEPRk5TLTw5Dhlpmj8mGIXeVQ3mJ9Ff3rlMRuaoIFqX9H9Yp3As2KuxwyKAR8QBC5WRY8+bjc3gm0+7GvADotm1vgpC44YJ6SiyAq8O6U= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1778484572; c=relaxed/simple; bh=E5C8dAUvAF6PK3tHWEWWwVfrtsNN2sP7v+XN8di0ieY=; h=MIME-Version:Date:Message-ID:Subject:From:To:Content-Type; b=Z/bU3jA7u986EqXTRsGEJ1r346iUBdGtHRQwWrtuDEsiP8ssMvbFLZC9Sj4q3waRDV7J6SKByu3HGTZQWsj49R1RwFBDnhjGqaBe3YFyJh3ZUU1s7TKMb65SWkZlJZsAIpwpRMAOfK1AK1aZsdYHNyn3B6dQSPmT5LoVgFc8MKE= 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=209.85.210.79 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-ot1-f79.google.com with SMTP id 46e09a7af769-7dcc5fa38faso6372400a34.1 for ; Mon, 11 May 2026 00:29:30 -0700 (PDT) X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20251104; t=1778484569; x=1779089369; h=to:from:subject:message-id:date:mime-version:x-gm-message-state :from:to:cc:subject:date:message-id:reply-to; bh=vrSzxj794BQXYltWHMaeU7bNnVUTfnI0zgOGBibu8Js=; b=mRz2khDxBRBRNl/ebPZvJyePwpQWi20ekghWm/oOGb9zBuEazr4mhMaI9ydyuMvlsq hCUAwglsInXI3vl0HDmvpPHuGr6/7zupdAtO/0El0ygXo26jjR2UGVDGD5E3iyCfn+Sy mpw1WW4kgCMrICpcM5PARed2iDe0zAJn39XhBl+0UTTo5DobqwmiAc0AQ2f/JH82cZWX YV5VCpv45XP13MYF/TAdISjn4OuziCjtpaVaHtDh/weEeVKE9oB+C6nZsLs5odFFP1dF YlVo+CC2rmtFRoUC8/bllhH5vCFMvGpgBH5daDLW4oSRR5lWTDam90QvcswNPgk1vR/b gqgw== X-Forwarded-Encrypted: i=1; AFNElJ/1nO7V/2ndR1rq/FDMA6EeT5vyEnwwvAHe7kzDEsVkwyf2DLolT8Pzp+Yp3URV50wx/XETgpc0g/dAU2c=@vger.kernel.org X-Gm-Message-State: AOJu0YxpEC6rX36bNxX/iwEgUCegjUy9xf2dTcMBx78g4hGuo+RMxzuw /lbeqkmlvRXLQmAG7rVbwM82HJmVlKkOcuJJaLexImwNFYQxLrEHPT+t2AMOozwDpYumdY6sPuP nAqNVBXemVdMn4c06BymZS9mWPSCVdbr9+DNpwMxpHbbsdHGYQy/pECzAvkM= Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 X-Received: by 2002:a05:6820:7510:b0:69b:545b:a182 with SMTP id 006d021491bc7-69b545ba243mr984468eaf.32.1778484569442; Mon, 11 May 2026 00:29:29 -0700 (PDT) Date: Mon, 11 May 2026 00:29:29 -0700 X-Google-Appengine-App-Id: s~syzkaller X-Google-Appengine-App-Id-Alias: syzkaller Message-ID: <6a018559.170a0220.286ecb.0000.GAE@google.com> Subject: [syzbot] [exfat?] WARNING in fat_add_entries From: syzbot To: hirofumi@mail.parknet.co.jp, linkinjeon@kernel.org, linux-fsdevel@vger.kernel.org, linux-kernel@vger.kernel.org, sj1557.seo@samsung.com, syzkaller-bugs@googlegroups.com Content-Type: text/plain; charset="UTF-8" Hello, syzbot found the following issue on: HEAD commit: adc1e5c6203c Merge tag 'efi-fixes-for-v7.1-1' of git://git.. git tree: upstream console output: https://syzkaller.appspot.com/x/log.txt?x=14b4bb26580000 kernel config: https://syzkaller.appspot.com/x/.config?x=7f195f6be48c12ec dashboard link: https://syzkaller.appspot.com/bug?extid=872e83c344f0ae2cf617 compiler: Debian clang version 21.1.8 (++20251221033036+2078da43e25a-1~exp1~20251221153213.50), Debian LLD 21.1.8 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-adc1e5c6.raw.xz vmlinux: https://storage.googleapis.com/syzbot-assets/f67d79b10054/vmlinux-adc1e5c6.xz kernel image: https://storage.googleapis.com/syzbot-assets/f9dcdab6fabb/bzImage-adc1e5c6.xz IMPORTANT: if you fix the issue, please add the following tag to the commit: Reported-by: syzbot+872e83c344f0ae2cf617@syzkaller.appspotmail.com loop0: detected capacity change from 128 to 0 FAT-fs (loop0): Directory bread(block 40) failed FAT-fs (loop0): Directory bread(block 40) failed ------------[ cut here ]------------ !buffer_uptodate(bh) WARNING: fs/buffer.c:1087 at mark_buffer_dirty+0x299/0x410 fs/buffer.c:1087, CPU#0: syz.0.0/5323 Modules linked in: CPU: 0 UID: 0 PID: 5323 Comm: syz.0.0 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 RIP: 0010:mark_buffer_dirty+0x299/0x410 fs/buffer.c:1087 Code: 4c 89 f7 e8 89 5d da ff 49 8b 3e be 40 00 00 00 5b 41 5c 41 5e 41 5f 5d e9 b4 63 fb ff e8 ef 93 6d ff eb 8c e8 e8 93 6d ff 90 <0f> 0b 90 e9 a5 fd ff ff e8 da 93 6d ff 90 0f 0b 90 e9 cf fd ff ff RSP: 0018:ffffc900057df208 EFLAGS: 00010287 RAX: ffffffff82583af8 RBX: ffff888046d92000 RCX: 0000000000100000 RDX: ffffc90020802000 RSI: 00000000000029e1 RDI: 00000000000029e2 RBP: ffffc900057df401 R08: ffff888046d92007 R09: 1ffff11008db2400 R10: dffffc0000000000 R11: ffffed1008db2401 R12: dffffc0000000000 R13: 00000000000002a0 R14: dffffc0000000000 R15: ffff888046e3ba50 FS: 00007f247469b6c0(0000) GS:ffff88808c885000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f247469aff8 CR3: 0000000039246000 CR4: 0000000000352ef0 Call Trace: mmb_mark_buffer_dirty+0x2f/0x200 fs/buffer.c:719 fat_add_entries+0x799/0x2320 fs/fat/dir.c:1362 vfat_add_entry+0x2def/0x3580 fs/fat/namei_vfat.c:675 vfat_create+0x148/0x270 fs/fat/namei_vfat.c:769 lookup_open fs/namei.c:4511 [inline] open_last_lookups fs/namei.c:4611 [inline] path_openat+0x1395/0x3860 fs/namei.c:4855 do_file_open+0x23e/0x4a0 fs/namei.c:4887 do_sys_openat2+0x113/0x200 fs/open.c:1364 do_sys_open fs/open.c:1370 [inline] __do_sys_creat fs/open.c:1448 [inline] __se_sys_creat fs/open.c:1442 [inline] __x64_sys_creat+0x8f/0xc0 fs/open.c:1442 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0x15f/0xf80 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f247379cdd9 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:00007f247469afe8 EFLAGS: 00000246 ORIG_RAX: 0000000000000055 RAX: ffffffffffffffda RBX: 00007f2473a16090 RCX: 00007f247379cdd9 RDX: 0000000000000000 RSI: 0000000000000009 RDI: 0000200000000e00 RBP: 00007f2473832d69 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007f2473a16128 R14: 00007f2473a16090 R15: 00007ffd5e53e4e8 --- 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