From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mail-oi1-f208.google.com (mail-oi1-f208.google.com [209.85.167.208]) (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 0CCC8175A9C for ; Wed, 12 Aug 2026 05:00:40 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=209.85.167.208 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1786510842; cv=none; b=j54+xvEvjQ1mIpY4XBRPFKJl2wkl3TeFOEoGuoB99hr0uSNnwy5wAF5UkQzhgmClc9ycKvdeHtFcPiGp8rWnvyt0M2RSI8SbVRtjZmLb2PoDdzXqMjbRc8R1AMQ/MMFBTcIhbyQWFSefWGGfqXPNp09qIjigmfLFTzGVF86geko= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1786510842; c=relaxed/simple; bh=EhTxdoRY4Za9CVpw+rF0/GDu2Pavbm+8D8p+CV7k+Dk=; h=MIME-Version:Date:Message-ID:Subject:From:To:Content-Type; b=CO2rGTGpk2p/eeA1Ju1KKDxXoNSn/hpLMiRj7nEzM+KEAvikNtULAeTbBBwE4eIs+KgCXHwkO4CuEVBocGpXf7KBnuv3jEzKxc0EG7/mbJuER8SGrzKuvM/0HZywJ6r4CcHFTXMkhSJMj3zSmP/g6XqT+I08sh6aZEs2N3RqEaQ= 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=209.85.167.208 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-oi1-f208.google.com with SMTP id 5614622812f47-4b1bd8320ecso568597b6e.3 for ; Tue, 11 Aug 2026 22:00:40 -0700 (PDT) X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20251104; t=1786510840; x=1787115640; 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=whulqaPrA6Df/FKHJWt7zjRAPFi92MgfcdZDHlienVk=; b=V4gj9Qji/BGYXPvsSX26Eu/Aq/Q+7QDNRZFNIEsvLlMEahIsM4qoJPC7JgfjKEwJUC iJbC0iNnHD2tv0X4JBwoJs2l8y6p7Y5F9kq0lFZVKH/rQowKmFC2eJIrV9v36ajzAA2Z 8OuCWbZBeqR20xnZD8L2RI+/Qz+TVwVWGuujUuFxZEvze+AD6XQB9YGwgCRsQVDJztPi ALklNWF4TJ+9qF3rVXC6MLXcMHurm8i8u1vflwDSPhVioV//kY30z9fpCjib2IMTFJy4 5YlFtJcGPutqIC1bFzNAoSbjFNpGHaJnOD8ZEyOwGVia7SAVybrmP80g2g/zntAs7V8B 928g== X-Forwarded-Encrypted: i=1; AHgh+RqRCdzO/DHWACtvFSEfqnjK/orEzDB5gxVuCSl1l9D89pdTQkThP6NKPHjit25vMMFB5vlfXBQaMicxOQc=@vger.kernel.org X-Gm-Message-State: AOJu0YweaXkaYTq2mNsym5pFgUfEnff5kxvz2G9+a2mzPxCCuV1WXQTc W1lDydWtvfux4rJt3znAEZzuWyXcEXcHt+F/dqChjz3DdLX6LPgmcIzbyTyr67hncwpa5GgyaxB T5aNj2uA/jOLE/rSzFAHAHbiIKiQC6Lr4jSi+TRaSkp0xS52PPXz4bPooqFo= Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 X-Received: by 2002:a05:6808:1a0b:b0:486:8a11:6e8b with SMTP id 5614622812f47-4b21093a9f2mr2298203b6e.2.1786510839962; Tue, 11 Aug 2026 22:00:39 -0700 (PDT) Date: Tue, 11 Aug 2026 22:00:39 -0700 X-Google-Appengine-App-Id: s~syzkaller X-Google-Appengine-App-Id-Alias: syzkaller Message-ID: <6a7bfdf7.ed659fcc.23056a.007f.GAE@google.com> Subject: [syzbot] [jffs2?] KASAN: slab-use-after-free Read in jffs2_xattr_delete_inode From: syzbot To: dwmw2@infradead.org, linux-kernel@vger.kernel.org, linux-mtd@lists.infradead.org, richard@nod.at, syzkaller-bugs@googlegroups.com Content-Type: text/plain; charset="UTF-8" Hello, syzbot found the following issue on: HEAD commit: bcc44b6785f2 Merge tag 'drm-fixes-2026-08-08' of https://g.. git tree: upstream console output: https://syzkaller.appspot.com/x/log.txt?x=147d7e49580000 kernel config: https://syzkaller.appspot.com/x/.config?x=158601bb8cb292dd dashboard link: https://syzkaller.appspot.com/bug?extid=3a8099322b09d8d073d1 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: https://storage.googleapis.com/syzbot-assets/e4ca3ce763a0/disk-bcc44b67.raw.xz vmlinux: https://storage.googleapis.com/syzbot-assets/face1dc3e618/vmlinux-bcc44b67.xz kernel image: https://storage.googleapis.com/syzbot-assets/185a6a3df821/bzImage-bcc44b67.xz IMPORTANT: if you fix the issue, please add the following tag to the commit: Reported-by: syzbot+3a8099322b09d8d073d1@syzkaller.appspotmail.com RBP: 00007f5b86286090 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000001 R13: 00007f5b882b6038 R14: 00007f5b882b5fa0 R15: 00007ffe7e6b8828 ================================================================== BUG: KASAN: slab-use-after-free in jffs2_xattr_delete_inode+0x2c8/0x2d0 fs/jffs2/xattr.c:602 Read of size 4 at addr ffff888029725ee8 by task syz.8.1428/17657 CPU: 0 UID: 0 PID: 17657 Comm: syz.8.1428 Not tainted syzkaller #0 PREEMPT_{RT,(full)} Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/24/2026 Call Trace: dump_stack_lvl+0xe8/0x150 lib/dump_stack.c:120 print_address_description+0x55/0x1e0 mm/kasan/report.c:378 print_report+0x58/0x70 mm/kasan/report.c:482 kasan_report+0x117/0x150 mm/kasan/report.c:595 jffs2_xattr_delete_inode+0x2c8/0x2d0 fs/jffs2/xattr.c:602 jffs2_do_clear_inode+0x58/0x390 fs/jffs2/readinode.c:1418 evict+0x624/0xb50 fs/inode.c:825 jffs2_new_inode+0x49c/0xd00 fs/jffs2/fs.c:-1 jffs2_mkdir+0x192/0xeb0 fs/jffs2/dir.c:485 vfs_mkdir+0x402/0x620 fs/namei.c:5276 filename_mkdirat+0x289/0x520 fs/namei.c:5309 __do_sys_mkdirat fs/namei.c:5330 [inline] __se_sys_mkdirat+0x35/0x150 fs/namei.c:5327 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0x174/0x580 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f5b8802e0d9 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:00007f5b86286028 EFLAGS: 00000246 ORIG_RAX: 0000000000000102 RAX: ffffffffffffffda RBX: 00007f5b882b5fa0 RCX: 00007f5b8802e0d9 RDX: 0000000000000000 RSI: 0000200000000640 RDI: ffffffffffffff9c RBP: 00007f5b86286090 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000001 R13: 00007f5b882b6038 R14: 00007f5b882b5fa0 R15: 00007ffe7e6b8828 Allocated by task 14460: kasan_save_stack mm/kasan/common.c:57 [inline] kasan_save_track+0x3e/0x80 mm/kasan/common.c:78 unpoison_slab_object mm/kasan/common.c:340 [inline] __kasan_slab_alloc+0x6c/0x80 mm/kasan/common.c:366 kasan_slab_alloc include/linux/kasan.h:253 [inline] slab_post_alloc_hook mm/slub.c:4584 [inline] slab_alloc_node mm/slub.c:4917 [inline] kmem_cache_alloc_noprof+0x355/0x650 mm/slub.c:4931 jffs2_scan_make_ino_cache+0x89/0x1d0 fs/jffs2/scan.c:978 jffs2_scan_dirent_node fs/jffs2/scan.c:1099 [inline] jffs2_scan_eraseblock fs/jffs2/scan.c:831 [inline] jffs2_scan_medium+0x2b58/0x70c0 fs/jffs2/scan.c:151 jffs2_build_filesystem fs/jffs2/build.c:112 [inline] jffs2_do_mount_fs+0x775/0x22c0 fs/jffs2/build.c:416 jffs2_do_fill_super+0x555/0xc50 fs/jffs2/fs.c:574 mtd_get_sb+0x18a/0x410 drivers/mtd/mtdsuper.c:57 mtd_get_sb_by_nr drivers/mtd/mtdsuper.c:88 [inline] get_tree_mtd+0x4bd/0x7d0 drivers/mtd/mtdsuper.c:158 vfs_get_tree+0x92/0x2a0 fs/super.c:1700 fc_mount fs/namespace.c:1198 [inline] do_new_mount_fc fs/namespace.c:3765 [inline] do_new_mount+0x319/0xdc0 fs/namespace.c:3841 do_mount fs/namespace.c:4174 [inline] __do_sys_mount fs/namespace.c:4390 [inline] __se_sys_mount+0x31d/0x420 fs/namespace.c:4367 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0x174/0x580 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f Freed by task 7915: kasan_save_stack mm/kasan/common.c:57 [inline] kasan_save_track+0x3e/0x80 mm/kasan/common.c:78 kasan_save_free_info+0x40/0x50 mm/kasan/generic.c:584 poison_slab_object mm/kasan/common.c:253 [inline] __kasan_slab_free+0x5c/0x80 mm/kasan/common.c:285 kasan_slab_free include/linux/kasan.h:235 [inline] slab_free_hook mm/slub.c:2677 [inline] slab_free mm/slub.c:6377 [inline] kmem_cache_free+0x187/0x6c0 mm/slub.c:6504 jffs2_free_ino_caches+0xec/0x1c0 fs/jffs2/nodelist.c:497 jffs2_put_super+0x6c/0x170 fs/jffs2/super.c:335 generic_shutdown_super+0x13d/0x2d0 fs/super.c:647 kill_mtd_super+0x23/0x70 drivers/mtd/mtdsuper.c:174 jffs2_kill_sb+0x96/0xb0 fs/jffs2/super.c:350 deactivate_locked_super+0xbc/0x130 fs/super.c:477 cleanup_mnt+0x3d3/0x460 fs/namespace.c:1317 task_work_run+0x1d9/0x270 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:70 [inline] exit_to_user_mode_loop+0x1fa/0x730 kernel/entry/common.c:101 __exit_to_user_mode_prepare include/linux/irq-entry-common.h:207 [inline] syscall_exit_to_user_mode_prepare include/linux/irq-entry-common.h:230 [inline] syscall_exit_to_user_mode include/linux/entry-common.h:318 [inline] do_syscall_64+0x353/0x580 arch/x86/entry/syscall_64.c:100 entry_SYSCALL_64_after_hwframe+0x77/0x7f The buggy address belongs to the object at ffff888029725ec0 which belongs to the cache jffs2_inode_cache of size 48 The buggy address is located 40 bytes inside of freed 48-byte region [ffff888029725ec0, ffff888029725ef0) The buggy address belongs to the physical page: page: refcount:0 mapcount:0 mapping:0000000000000000 index:0xffff888029725700 pfn:0x29725 flags: 0x80000000000200(workingset|node=0|zone=1) page_type: f5(slab) raw: 0080000000000200 ffff888140435280 ffffea000085b790 ffff88801eb7ae88 raw: ffff888029725700 000000080040001c 00000000f5000000 0000000000000000 page dumped because: kasan: bad access detected page_owner tracks the page as allocated page last allocated via order 0, migratetype Unmovable, gfp_mask 0xd2cc0(GFP_KERNEL|__GFP_NOWARN|__GFP_NORETRY|__GFP_COMP|__GFP_NOMEMALLOC), pid 5878, tgid 5877 (syz.2.27), ts 110407811516, free_ts 110388090000 set_page_owner include/linux/page_owner.h:32 [inline] post_alloc_hook+0x1f9/0x250 mm/page_alloc.c:1859 prep_new_page mm/page_alloc.c:1867 [inline] get_page_from_freelist+0x262a/0x26a0 mm/page_alloc.c:3946 __alloc_frozen_pages_noprof+0x18d/0x380 mm/page_alloc.c:5304 alloc_slab_page mm/slub.c:3266 [inline] allocate_slab+0x79/0x5e0 mm/slub.c:3380 new_slab mm/slub.c:3426 [inline] refill_objects+0x2d8/0x350 mm/slub.c:7310 refill_sheaf mm/slub.c:2804 [inline] __pcs_replace_empty_main+0x330/0x690 mm/slub.c:4675 alloc_from_pcs mm/slub.c:4773 [inline] slab_alloc_node mm/slub.c:4905 [inline] kmem_cache_alloc_noprof+0x452/0x650 mm/slub.c:4931 jffs2_do_new_inode+0x27/0x500 fs/jffs2/write.c:28 jffs2_new_inode+0x46e/0xd00 fs/jffs2/fs.c:466 jffs2_create+0x87/0x320 fs/jffs2/dir.c:182 lookup_open fs/namei.c:4508 [inline] open_last_lookups fs/namei.c:4608 [inline] path_openat+0x1344/0x3850 fs/namei.c:4860 do_file_open+0x23e/0x4a0 fs/namei.c:4892 do_sys_openat2+0x115/0x200 fs/open.c:1368 do_sys_open fs/open.c:1374 [inline] __do_sys_openat fs/open.c:1390 [inline] __se_sys_openat fs/open.c:1385 [inline] __x64_sys_openat+0x138/0x170 fs/open.c:1385 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0x174/0x580 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f page last free pid 20 tgid 20 stack trace: reset_page_owner include/linux/page_owner.h:25 [inline] __free_pages_prepare mm/page_alloc.c:1406 [inline] __free_frozen_pages+0x10e7/0x11c0 mm/page_alloc.c:2950 rcu_do_batch kernel/rcu/tree.c:2645 [inline] rcu_core kernel/rcu/tree.c:2897 [inline] rcu_cpu_kthread+0x950/0x1480 kernel/rcu/tree.c:2985 smpboot_thread_fn+0x57c/0xa80 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 Memory state around the buggy address: ffff888029725d80: fa fb fb fb fb fb fc fc fa fb fb fb fb fb fc fc ffff888029725e00: fa fb fb fb fb fb fc fc fa fb fb fb fb fb fc fc >ffff888029725e80: fa fb fb fb fb fb fc fc fa fb fb fb fb fb fc fc ^ ffff888029725f00: fa fb fb fb fb fb fc fc fa fb fb fb fb fb fc fc ffff888029725f80: fa fb fb fb fb fb fc fc fa fb fb fb fb fb fc fc ================================================================== --- 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