From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mail-oi1-f205.google.com (mail-oi1-f205.google.com [209.85.167.205]) (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 E3692175A91 for ; Tue, 16 Jun 2026 00:12:24 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=209.85.167.205 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1781568747; cv=none; b=d6xWobbuAvSWiUh9GupfHnhI6++y8UXUuyzNKjIV660TxcDrPf8zaH46+gw8VZYK6yzLhp6WULaJldkMCiEEZOxLFKjI4QLf16vFz4ryZjHwoFuOKq5EJZMmB9kZjrlfFP3Aa28pxFOOEFffkJpB+Bg7G3IywrDPVN0q1e1ZekQ= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1781568747; c=relaxed/simple; bh=Q7/mRFxy0q8T21qT1e99U8/wb/jMv4L428XKzb/1++A=; h=MIME-Version:Date:Message-ID:Subject:From:To:Content-Type; b=no+34LCEmHk0B3PA7n/U2N+lBBY5nhHX0Z7AIgvEdwhs0tXBiHECjCPZiK04Ps5aQsHTugpxpE76111z2+XdxBiVxh6I6yI5M4XrmcHxbqytlX9Eyt9jrQmkz5HSzGToDtYQQ8jFC+OIQqQxl1a5L2bxNixftAt0ZzNnRX8qmzE= 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=209.85.167.205 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-f205.google.com with SMTP id 5614622812f47-4863a0c3105so6581266b6e.3 for ; Mon, 15 Jun 2026 17:12:24 -0700 (PDT) X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20251104; t=1781568744; x=1782173544; h=to:from:subject:message-id:date:mime-version:x-gm-message-state :from:to:cc:subject:date:message-id:reply-to; bh=6fFvbAhvGTJqgNXDel7BChR7iY0CTU5FL9l+rJRxn8A=; b=nZLI5SudKPhnf0nH5/ThtOj3xsWDQVoJ/3heMSsBpsPZ7JKfgjv0PY4zW7p1X4J0IW l5MrObdIxoLZFZ7n72Nf6rTCTeokwGSMYwZGE+jlgqKm/WIPeEGf0LLHJybhnPP45v1g ODjX+JjXKcD/jni2Z/3GYtkM9IQusUeyIAwx5FamhKaDOL5lOk/Bw8N7LGV9amAK+Qxr pB8RK8hrR5ic0C1PXipzLPERF/UbZJ6XNn/kCByktZ8/W3S3lWJ/MKavclxAI2wS9OAK U9sk7ng29/1/C7wthz0iSaRUQfZYixrF8vTGk+uASneaFjyNQqp1yueTwU9enb3n80ay OuPg== X-Gm-Message-State: AOJu0YwAAxUtiGtX/F/OfkzA4bj9oB8CkvIkAi2PLv17zQYvLQCR2dHm xtQO9isZ1+YuRBPfslJWUqwtH3l6bFo8MyG8Fk2xCEMT75kAocW6MvsQhdSJIvGAC2kXgH23S0I /KqRWm714nhHmWOotfu7ybC/gtOFObEQarcrOLQM87bkJUxzJZ6ECP/veMM0c4Q== Precedence: bulk X-Mailing-List: linux-fsdevel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 X-Received: by 2002:a05:6808:3023:b0:467:1f38:bc1a with SMTP id 5614622812f47-4884c0b95f7mr1032047b6e.7.1781568743905; Mon, 15 Jun 2026 17:12:23 -0700 (PDT) Date: Mon, 15 Jun 2026 17:12:23 -0700 X-Google-Appengine-App-Id: s~syzkaller X-Google-Appengine-App-Id-Alias: syzkaller Message-ID: <6a3094e7.428ffe26.258b27.0171.GAE@google.com> Subject: [syzbot] [fs?] KASAN: slab-use-after-free Read in dentry_kill From: syzbot To: linux-fsdevel@vger.kernel.org, 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: c425609d6ac4 Add linux-next specific files for 20260612 git tree: linux-next console output: https://syzkaller.appspot.com/x/log.txt?x=16f6f8ae580000 kernel config: https://syzkaller.appspot.com/x/.config?x=d7a56b1e89b63439 dashboard link: https://syzkaller.appspot.com/bug?extid=e514d3879b0ce2a189f1 compiler: Debian clang version 22.1.6 (++20260514074242+fc4aad7b5db3-1~exp1~20260514074407.73), Debian LLD 22.1.6 Unfortunately, I don't have any reproducer for this issue yet. Downloadable assets: disk image: https://storage.googleapis.com/syzbot-assets/7fab9a8df61a/disk-c425609d.raw.xz vmlinux: https://storage.googleapis.com/syzbot-assets/c2577196651b/vmlinux-c425609d.xz kernel image: https://storage.googleapis.com/syzbot-assets/053557a7471e/bzImage-c425609d.xz IMPORTANT: if you fix the issue, please add the following tag to the commit: Reported-by: syzbot+e514d3879b0ce2a189f1@syzkaller.appspotmail.com ================================================================== BUG: KASAN: slab-use-after-free in __raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:132 [inline] BUG: KASAN: slab-use-after-free in _raw_spin_lock_irqsave+0x40/0x60 kernel/locking/spinlock.c:166 Read of size 1 at addr ffff888029bc58e0 by task syz-executor/13794 CPU: 1 UID: 0 PID: 13794 Comm: syz-executor Tainted: G L syzkaller #0 PREEMPT_{RT,(full)} Tainted: [L]=SOFTLOCKUP Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/09/2026 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 __kasan_check_byte+0x2a/0x40 mm/kasan/common.c:574 kasan_check_byte include/linux/kasan.h:402 [inline] lock_acquire+0x84/0x350 kernel/locking/lockdep.c:5844 __raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:132 [inline] _raw_spin_lock_irqsave+0x40/0x60 kernel/locking/spinlock.c:166 rt_mutex_slowunlock+0xbf/0xa20 kernel/locking/rtmutex.c:1430 dentry_kill+0x520/0x880 fs/dcache.c:-1 shrink_kill fs/dcache.c:1275 [inline] shrink_dentry_list+0x20c/0x320 fs/dcache.c:1292 shrink_dcache_tree+0xe7/0x410 fs/dcache.c:1725 shrink_dcache_parent fs/dcache.c:1767 [inline] d_invalidate+0xde/0x260 fs/dcache.c:1870 proc_invalidate_siblings_dcache+0x3d3/0x6c0 fs/proc/inode.c:142 release_task+0x11c8/0x16c0 kernel/exit.c:291 wait_task_zombie kernel/exit.c:1309 [inline] wait_consider_task+0x197d/0x2df0 kernel/exit.c:1536 do_wait_thread kernel/exit.c:1599 [inline] __do_wait+0x14b/0x720 kernel/exit.c:1717 do_wait+0x1e7/0x510 kernel/exit.c:1751 kernel_wait4+0x232/0x2b0 kernel/exit.c:1910 __do_sys_wait4 kernel/exit.c:1938 [inline] __se_sys_wait4 kernel/exit.c:1934 [inline] __x64_sys_wait4+0x166/0x240 kernel/exit.c:1934 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: 0033:0x7ff38ee8d68e Code: 08 0f 85 a5 a8 ff ff 49 89 fb 48 89 f0 48 89 d7 48 89 ce 4c 89 c2 4d 89 ca 4c 8b 44 24 08 4c 8b 4c 24 10 4c 89 5c 24 08 0f 05 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 80 00 00 00 00 48 83 ec 08 RSP: 002b:00007fff40829ad8 EFLAGS: 00000246 ORIG_RAX: 000000000000003d RAX: ffffffffffffffda RBX: 0000555593968500 RCX: 00007ff38ee8d68e RDX: 0000000040000001 RSI: 00007fff40829b7c RDI: ffffffffffffffff RBP: 00007fff40829b7c R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000001388 R13: 00000000000927c0 R14: 0000000000193c5e R15: 00007fff40829bd0 Allocated by task 23590: 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:4610 [inline] slab_alloc_node mm/slub.c:4943 [inline] kmem_cache_alloc_lru_noprof+0x347/0x6a0 mm/slub.c:4976 __d_alloc+0x37/0x6f0 fs/dcache.c:1902 d_alloc_parallel+0xde/0x16c0 fs/dcache.c:2761 __lookup_slow+0x82/0x2f0 fs/namei.c:1904 lookup_slow+0x53/0x70 fs/namei.c:1936 walk_component fs/namei.c:2282 [inline] link_path_walk+0x12a5/0x1910 fs/namei.c:2653 path_openat+0x23c/0x3850 fs/namei.c:4855 do_file_open+0x23e/0x4a0 fs/namei.c:4888 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 Freed by task 29: 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:2703 [inline] slab_free mm/slub.c:6402 [inline] kmem_cache_free+0x187/0x6c0 mm/slub.c:6529 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 Last potentially related work creation: kasan_save_stack+0x3e/0x60 mm/kasan/common.c:57 kasan_record_aux_stack+0xbd/0xd0 mm/kasan/generic.c:556 __call_rcu_common kernel/rcu/tree.c:3159 [inline] call_rcu+0xee/0x8b0 kernel/rcu/tree.c:3279 dentry_kill+0x4d3/0x880 fs/dcache.c:845 finish_dput+0x1a/0x260 fs/dcache.c:1001 proc_invalidate_siblings_dcache+0x3db/0x6c0 fs/proc/inode.c:143 release_task+0x11c8/0x16c0 kernel/exit.c:291 exit_notify kernel/exit.c:805 [inline] do_exit+0x168c/0x2360 kernel/exit.c:1016 do_group_exit+0x22d/0x2f0 kernel/exit.c:1147 get_signal+0x121b/0x12c0 kernel/signal.c:3038 arch_do_signal_or_restart+0xbb/0x860 arch/x86/kernel/signal.c:337 __exit_to_user_mode_loop kernel/entry/common.c:66 [inline] exit_to_user_mode_loop+0x104/0x730 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 ffff888029bc5810 which belongs to the cache dentry of size 376 The buggy address is located 208 bytes inside of freed 376-byte region [ffff888029bc5810, ffff888029bc5988) The buggy address belongs to the physical page: page: refcount:0 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x29bc4 head: order:1 mapcount:0 entire_mapcount:0 nr_pages_mapped:0 pincount:0 memcg:ffff88802c443d01 flags: 0x80000000000040(head|node=0|zone=1) page_type: f5(slab) raw: 0080000000000040 ffff88801be88500 dead000000000100 dead000000000122 raw: 0000000000000000 0000000800120012 00000000f5000000 ffff88802c443d01 head: 0080000000000040 ffff88801be88500 dead000000000100 dead000000000122 head: 0000000000000000 0000000800120012 00000000f5000000 ffff88802c443d01 head: 0080000000000001 ffffffffffffff81 00000000ffffffff 00000000ffffffff head: 0000000000000000 0000000000000000 00000000ffffffff 0000000000000002 page dumped because: kasan: bad access detected page_owner tracks the page as allocated page last allocated via order 1, migratetype Reclaimable, gfp_mask 0xd20d0(__GFP_RECLAIMABLE|__GFP_IO|__GFP_FS|__GFP_NOWARN|__GFP_NORETRY|__GFP_COMP|__GFP_NOMEMALLOC), pid 4974, tgid 4974 (udevd), ts 43549004452, free_ts 31788091603 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+0x2639/0x26b0 mm/page_alloc.c:3946 __alloc_frozen_pages_noprof+0x18d/0x380 mm/page_alloc.c:5304 alloc_slab_page mm/slub.c:3292 [inline] allocate_slab+0x79/0x5e0 mm/slub.c:3406 new_slab mm/slub.c:3452 [inline] refill_objects+0x2d8/0x350 mm/slub.c:7335 refill_sheaf mm/slub.c:2830 [inline] __pcs_replace_empty_main+0x330/0x690 mm/slub.c:4701 alloc_from_pcs mm/slub.c:4799 [inline] slab_alloc_node mm/slub.c:4931 [inline] kmem_cache_alloc_lru_noprof+0x45e/0x6a0 mm/slub.c:4976 __d_alloc+0x37/0x6f0 fs/dcache.c:1902 d_alloc_parallel+0xde/0x16c0 fs/dcache.c:2761 __lookup_slow+0x82/0x2f0 fs/namei.c:1904 lookup_slow+0x53/0x70 fs/namei.c:1936 walk_component fs/namei.c:2282 [inline] lookup_last fs/namei.c:2789 [inline] path_lookupat+0x3f5/0x8c0 fs/namei.c:2813 filename_lookup+0x265/0x5d0 fs/namei.c:2842 do_faccessat+0x632/0xdc0 fs/open.c:488 __do_sys_faccessat2 fs/open.c:542 [inline] __se_sys_faccessat2 fs/open.c:539 [inline] __x64_sys_faccessat2+0x9a/0xb0 fs/open.c:539 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0x174/0x580 arch/x86/entry/syscall_64.c:94 page last free pid 4977 tgid 4977 stack trace: reset_page_owner include/linux/page_owner.h:25 [inline] __free_pages_prepare mm/page_alloc.c:1406 [inline] __free_frozen_pages+0x10de/0x11c0 mm/page_alloc.c:2950 __slab_free+0x252/0x2a0 mm/slub.c:5764 qlink_free mm/kasan/quarantine.c:163 [inline] qlist_free_all+0x99/0x100 mm/kasan/quarantine.c:179 kasan_quarantine_reduce+0x148/0x160 mm/kasan/quarantine.c:286 __kasan_slab_alloc+0x22/0x80 mm/kasan/common.c:350 kasan_slab_alloc include/linux/kasan.h:253 [inline] slab_post_alloc_hook mm/slub.c:4610 [inline] slab_alloc_node mm/slub.c:4943 [inline] kmem_cache_alloc_noprof+0x348/0x6b0 mm/slub.c:4957 alloc_filename fs/namei.c:147 [inline] do_getname+0x2e/0x250 fs/namei.c:187 class_filename_flags_constructor include/linux/fs.h:2561 [inline] do_sys_openat2+0xcc/0x200 fs/open.c:1367 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 Memory state around the buggy address: ffff888029bc5780: 00 00 00 00 00 00 00 00 00 00 fc fc fc fc fc fc ffff888029bc5800: fc fc fa fb fb fb fb fb fb fb fb fb fb fb fb fb >ffff888029bc5880: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ^ ffff888029bc5900: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff888029bc5980: fb fc fc fc fc fc fc fc fc 00 00 00 00 00 00 00 ================================================================== --- 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