From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mail-oi2-f3.google.com (mail-oi2-f3.google.com [74.125.231.195]) (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 1A04E2868B4 for ; Tue, 25 Aug 2026 00:39:34 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=74.125.231.195 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1787618376; cv=none; b=Gfc5iHQ2WJLuy22Tsnxwck2L0cCylU04aX5OYl3VBN11jZHgIc2eLh83zGmERk5J+RDWjwR6nwe37T4OpGcl7Pb2WNujwMFW4jB4dXYimd3FW2zcVvMhaP22tohc51fuVHSxz4iBokftJjnv6wVhXOsYKwAXHvTte5aFXLVTwjw= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1787618376; c=relaxed/simple; bh=f6BShjRzUODr2OSYJ6bjkxrER6HZQDu6Z9nSxvcwFnM=; h=MIME-Version:Date:Message-ID:Subject:From:To:Content-Type; b=pQk6C4ZXcKyTGyiUSN2yBGDboADA1dIdb3jSAIGSPFjrlB/oBS7+rfu8qOZVLh43SpaM0822K/YbNOI5v6qXlf+t7v9gs0x/nkHTDNf+mv1rE6DjfLHQVTijDamVRlFCsG/kFU7KS+/UR2usIp3NT+eiodkIZ0F6upf4ZYRKULE= 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=74.125.231.195 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-oi2-f3.google.com with SMTP id 46e09a7af769-7e9f7e652a5so967458a34.1 for ; Mon, 24 Aug 2026 17:39:34 -0700 (PDT) X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20251104; t=1787618374; x=1788223174; 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=u7cSS0MNLQbYVyzUM0whexANhXuqlkBlix9eUHfZ4bQ=; b=YvsA4jfQrOmPOKk3Md2mM+6XGP1rDfVi+Mfu+liWI08AVfziIoLDriPYaRbdLT+CJs NEAjEu1Fkrq7tqostvBjtct7Er58ai+WcnlzITmqidOdyRBITpqHAZI68ORONIxGrxmW YRu8LqKQC0duSzQgjWP9syXyhR2wGCVdCTWTnouKnxJPPSJw0VYMMB1iuSJDstZ5uEGg n/PEs1IGLcV4/3bS37TjBr0MnBWWEAgDf2V5jRrOn5ZPO9R//WzXn4AOkLnFSep920Gp vTwZweKRfAGZapSDa5jYTLugQ0Xt1VphNN+dd1vW9j5sb6N+LLrVIHsFf0xyRnzfgDG0 YIrw== X-Forwarded-Encrypted: i=1; AHgh+RpWHYAarHxN37TczyvC2LxlWYNFG3VUa7iR56HAWH3bXpREgV6XVcFrOJ+wyt++7WIr12nZCgcLRb1Z6a0Q@vger.kernel.org X-Gm-Message-State: AFuF++kWLfLeqQ2C54go1cU8GUsAHUrtClfonk+FlJ9nmUgcHy1qM3ws KaUK7tWYH9wNRMY/YoXlhCOHB2XSzA5QS9+eGvnvfiSBg4/4+14T58kLSpPJmDzfXm6JD5n9zEP sNt4vplrUkO8gpEbd9L7LqTaVCdm+XkJ1euOkzyuF9qzDt5tL8WrrwGyycYU= Precedence: bulk X-Mailing-List: linux-fsdevel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 X-Received: by 2002:a05:6808:1826:b0:4b2:e95f:37cf with SMTP id 5614622812f47-4b309a6198emr23302597b6e.8.1787618373984; Mon, 24 Aug 2026 17:39:33 -0700 (PDT) Date: Mon, 24 Aug 2026 17:39:33 -0700 X-Google-Appengine-App-Id: s~syzkaller X-Google-Appengine-App-Id-Alias: syzkaller Message-ID: <6a8ce445.dbb3a75c.7844.0016.GAE@google.com> Subject: [syzbot] [fs?] KASAN: slab-use-after-free Write in do_bad_area From: syzbot To: brauner@kernel.org, jack@suse.cz, linux-fsdevel@vger.kernel.org, linux-kernel@vger.kernel.org, syzkaller-bugs@googlegroups.com, viro@zeniv.linux.org.uk Content-Type: text/plain; charset="UTF-8" Hello, syzbot found the following issue on: HEAD commit: a4ff2be345d0 Merge tag 'v7.3-p1' of git://git.kernel.org/p.. git tree: https://kernel.googlesource.com/pub/scm/linux/kernel/git/torvalds/linux master console output: https://syzkaller.appspot.com/x/log.txt?x=17a7119e580000 kernel config: https://syzkaller.appspot.com/x/.config?x=6f93b08316c84592 dashboard link: https://syzkaller.appspot.com/bug?extid=7bf725ed337e37307001 compiler: aarch64-linux-gnu-gcc (Debian 14.2.0-19) 14.2.0, GNU ld (GNU Binutils for Debian) 2.44 userspace arch: arm64 Unfortunately, I don't have any reproducer for this issue yet. Downloadable assets: disk image (non-bootable): https://storage.googleapis.com/syzbot-assets/fa3fbcfdac58/non_bootable_disk-a4ff2be3.raw.xz vmlinux: https://storage.googleapis.com/syzbot-assets/46529dd0eb0a/vmlinux-a4ff2be3.xz kernel image: https://storage.googleapis.com/syzbot-assets/d5f867ea2263/Image-a4ff2be3.gz.xz IMPORTANT: if you fix the issue, please add the following tag to the commit: Reported-by: syzbot+7bf725ed337e37307001@syzkaller.appspotmail.com ================================================================== BUG: KASAN: slab-use-after-free in __lse__cmpxchg_case_acq_64 arch/arm64/include/asm/atomic_lse.h:272 [inline] BUG: KASAN: slab-use-after-free in __cmpxchg_case_acq_64 arch/arm64/include/asm/cmpxchg.h:122 [inline] BUG: KASAN: slab-use-after-free in __cmpxchg_acq arch/arm64/include/asm/cmpxchg.h:170 [inline] BUG: KASAN: slab-use-after-free in raw_atomic64_cmpxchg_acquire include/linux/atomic/atomic-arch-fallback.h:4181 [inline] BUG: KASAN: slab-use-after-free in raw_atomic64_try_cmpxchg_acquire include/linux/atomic/atomic-arch-fallback.h:4299 [inline] BUG: KASAN: slab-use-after-free in raw_atomic_long_try_cmpxchg_acquire include/linux/atomic/atomic-long.h:1482 [inline] BUG: KASAN: slab-use-after-free in atomic_long_try_cmpxchg_acquire include/linux/atomic/atomic-instrumented.h:4458 [inline] BUG: KASAN: slab-use-after-free in __mutex_trylock_fast kernel/locking/mutex.c:161 [inline] BUG: KASAN: slab-use-after-free in mutex_lock_interruptible+0x10/0x70 kernel/locking/mutex.c:1109 Write at addr faf00000079e3f00 by task syz-executor/3375 Pointer tag: [fa], memory tag: [fe] CPU: 0 UID: 0 PID: 3375 Comm: syz-executor Tainted: G L syzkaller #0 PREEMPT Tainted: [L]=SOFTLOCKUP Hardware name: linux,dummy-virt (DT) Call trace: dump_backtrace arch/arm64/kernel/stacktrace.c:498 [inline] (C) show_stack+0x18/0x24 arch/arm64/kernel/stacktrace.c:499 (C) __dump_stack lib/dump_stack.c:94 [inline] dump_stack_lvl+0x60/0x80 lib/dump_stack.c:120 print_address_description mm/kasan/report.c:378 [inline] print_report+0x1c4/0x4b0 mm/kasan/report.c:482 kasan_report+0x84/0xac mm/kasan/report.c:595 report_tag_fault arch/arm64/mm/fault.c:368 [inline] do_tag_recovery arch/arm64/mm/fault.c:380 [inline] __do_kernel_fault+0x1b4/0x220 arch/arm64/mm/fault.c:424 do_bad_area+0x68/0x80 arch/arm64/mm/fault.c:529 do_tag_check_fault+0x34/0x44 arch/arm64/mm/fault.c:909 do_mem_abort+0x40/0x90 arch/arm64/mm/fault.c:985 el1_abort+0x44/0x64 arch/arm64/kernel/entry-common.c:342 el1h_64_sync_handler+0x50/0xac arch/arm64/kernel/entry-common.c:469 el1h_64_sync+0x6c/0x70 arch/arm64/kernel/entry.S:585 __lse__cmpxchg_case_acq_64 arch/arm64/include/asm/atomic_lse.h:272 [inline] (P) __cmpxchg_case_acq_64 arch/arm64/include/asm/cmpxchg.h:122 [inline] (P) __cmpxchg_acq arch/arm64/include/asm/cmpxchg.h:170 [inline] (P) raw_atomic64_cmpxchg_acquire include/linux/atomic/atomic-arch-fallback.h:4181 [inline] (P) raw_atomic64_try_cmpxchg_acquire include/linux/atomic/atomic-arch-fallback.h:4299 [inline] (P) raw_atomic_long_try_cmpxchg_acquire include/linux/atomic/atomic-long.h:1482 [inline] (P) atomic_long_try_cmpxchg_acquire include/linux/atomic/atomic-instrumented.h:4458 [inline] (P) __mutex_trylock_fast kernel/locking/mutex.c:161 [inline] (P) mutex_lock_interruptible+0x10/0x70 kernel/locking/mutex.c:1109 (P) do_dentry_open+0x128/0x4fc fs/open.c:996 vfs_open+0x2c/0xe8 fs/open.c:1101 do_open fs/namei.c:4837 [inline] path_openat+0x5b4/0x960 fs/namei.c:5000 do_file_open+0xb0/0x168 fs/namei.c:5029 do_sys_openat2+0x84/0x104 fs/open.c:1417 do_sys_open fs/open.c:1423 [inline] __do_sys_openat fs/open.c:1439 [inline] __se_sys_openat fs/open.c:1434 [inline] __arm64_sys_openat+0x64/0xc0 fs/open.c:1434 __invoke_syscall arch/arm64/kernel/syscall.c:35 [inline] invoke_syscall+0x54/0x10c arch/arm64/kernel/syscall.c:49 el0_svc_common.constprop.0+0x40/0xe0 arch/arm64/kernel/syscall.c:121 do_el0_svc+0x1c/0x34 arch/arm64/kernel/syscall.c:140 el0_svc+0x38/0x1fc arch/arm64/kernel/entry-common.c:758 el0t_64_sync_handler+0xa0/0xe4 arch/arm64/kernel/entry-common.c:777 el0t_64_sync+0x1a4/0x1a8 arch/arm64/kernel/entry.S:590 Allocated by task 4267: kasan_save_stack+0x3c/0x64 mm/kasan/common.c:57 save_stack_info+0x40/0x160 mm/kasan/tags.c:106 kasan_save_alloc_info+0x14/0x20 mm/kasan/tags.c:142 poison_kmalloc_redzone mm/kasan/common.c:398 [inline] poison_kmalloc_redzone mm/kasan/common.c:371 [inline] __kasan_kmalloc+0xf8/0x120 mm/kasan/common.c:415 kasan_kmalloc include/linux/kasan.h:263 [inline] __kmalloc_cache_noprof+0x1c0/0x460 mm/slub.c:5489 _kmalloc_noprof include/linux/slab.h:988 [inline] _kzalloc_noprof include/linux/slab.h:1309 [inline] activate_ep_files drivers/usb/gadget/legacy/inode.c:1601 [inline] gadgetfs_bind+0xd0/0x3c0 drivers/usb/gadget/legacy/inode.c:1692 gadget_bind_driver+0x90/0x284 drivers/usb/gadget/udc/core.c:1662 call_driver_probe drivers/base/dd.c:628 [inline] really_probe+0xbc/0x2bc drivers/base/dd.c:706 __driver_probe_device+0x11c/0x184 drivers/base/dd.c:868 driver_probe_device+0x3c/0x114 drivers/base/dd.c:898 __driver_attach+0x90/0x180 drivers/base/dd.c:1292 bus_for_each_dev+0x7c/0xdc drivers/base/bus.c:383 driver_attach+0x24/0x30 drivers/base/dd.c:1310 bus_add_driver+0xe4/0x208 drivers/base/bus.c:763 driver_register+0x68/0x130 drivers/base/driver.c:174 usb_gadget_register_driver_owner+0x54/0xfc drivers/usb/gadget/udc/core.c:1752 dev_config+0x214/0x484 drivers/usb/gadget/legacy/inode.c:1883 vfs_write+0xd4/0x36c fs/read_write.c:685 ksys_write+0x70/0x108 fs/read_write.c:739 __do_sys_write fs/read_write.c:750 [inline] __se_sys_write fs/read_write.c:747 [inline] __arm64_sys_write+0x18/0x24 fs/read_write.c:747 __invoke_syscall arch/arm64/kernel/syscall.c:35 [inline] invoke_syscall+0x54/0x10c arch/arm64/kernel/syscall.c:49 el0_svc_common.constprop.0+0x40/0xe0 arch/arm64/kernel/syscall.c:121 do_el0_svc+0x1c/0x34 arch/arm64/kernel/syscall.c:140 el0_svc+0x38/0x1fc arch/arm64/kernel/entry-common.c:758 el0t_64_sync_handler+0xa0/0xe4 arch/arm64/kernel/entry-common.c:777 el0t_64_sync+0x1a4/0x1a8 arch/arm64/kernel/entry.S:590 Freed by task 3478: kasan_save_stack+0x3c/0x64 mm/kasan/common.c:57 save_stack_info+0x40/0x160 mm/kasan/tags.c:106 kasan_save_free_info+0x18/0x40 mm/kasan/tags.c:147 poison_slab_object mm/kasan/common.c:253 [inline] __kasan_slab_free+0xe8/0x160 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] kfree+0x150/0x41c mm/slub.c:6692 put_ep.part.0+0x44/0x60 drivers/usb/gadget/legacy/inode.c:225 put_ep include/linux/refcount.h:396 [inline] destroy_ep_files+0x104/0x170 drivers/usb/gadget/legacy/inode.c:1582 gadgetfs_unbind+0x7c/0xc0 drivers/usb/gadget/legacy/inode.c:1655 gadget_unbind_driver+0x7c/0x118 drivers/usb/gadget/udc/core.c:1724 device_remove+0x4c/0x80 drivers/base/dd.c:616 __device_release_driver drivers/base/dd.c:1349 [inline] device_release_driver_internal+0x1cc/0x224 drivers/base/dd.c:1372 driver_detach+0x4c/0xb0 drivers/base/dd.c:1435 bus_remove_driver+0x6c/0xbc drivers/base/bus.c:832 driver_unregister+0x30/0x60 drivers/base/driver.c:202 usb_gadget_unregister_driver+0x20/0x40 drivers/usb/gadget/udc/core.c:1784 dev_release+0x68/0x80 drivers/usb/gadget/legacy/inode.c:1198 __fput+0xcc/0x2f8 fs/file_table.c:512 delayed_fput+0x50/0x6c fs/file_table.c:535 process_one_work+0x180/0x2d0 kernel/workqueue.c:3322 process_scheduled_works kernel/workqueue.c:3405 [inline] worker_thread+0x18c/0x300 kernel/workqueue.c:3486 kthread+0x118/0x130 kernel/kthread.c:436 ret_from_fork+0x10/0x20 arch/arm64/kernel/entry.S:854 The buggy address belongs to the object at fff00000079e3f00 which belongs to the cache kmalloc-192 of size 192 The buggy address is located 0 bytes inside of 192-byte region [fff00000079e3f00, fff00000079e3fc0) The buggy address belongs to the physical page: page: refcount:0 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x479e3 flags: 0x1ffc00000000000(node=0|zone=0|lastcpupid=0x7ff|kasantag=0x0) page_type: f5(slab) raw: 01ffc00000000000 f9f0000003401300 dead000000000122 0000000000000000 raw: 0000000000000000 0000000800150015 00000000f5000000 0000000000000000 page dumped because: kasan: bad access detected Memory state around the buggy address: fff00000079e3d00: f9 f9 f9 f9 f9 f9 f9 f9 fb fb fb fb fb fb fb fb fff00000079e3e00: fb fb fb fb fe fe fe fe fe fe fe fe fe fe fe fe >fff00000079e3f00: fe fe fe fe fe fe fe fe fe fe fe fe fe fe fe fe ^ fff00000079e4000: fe fe fe fe fe fe fe fe fe fe fe fe fe fe fe fe fff00000079e4100: fe fe fe fe fe fe fe fe fe fe fe fe fe fe fe fe ================================================================== --- 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