From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mail-oi1-f199.google.com (mail-oi1-f199.google.com [209.85.167.199]) (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 B77A113CF82 for ; Tue, 6 Oct 2026 02:52:29 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=209.85.167.199 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1791255151; cv=none; b=qj5ajgPEvvKi62gXs9c5Zb6tU0SYzDeRceP4mOk8sE6EP4LC9Y+KWhNrzoVr5Jlk0kbgEgJXj6iL1NWb4sRtHV5rA83fQ+vktcHwQC+c76yoim8gJrqqNzXPalf0g4teXeahkfSDwsi1j1o3p3uOj0ApFVpk87H5GiULjY4fTK0= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1791255151; c=relaxed/simple; bh=PoOjC/dVjJSZWceSOaILIVvLCUiBqOOKOkYm21GURMg=; h=MIME-Version:Date:Message-ID:Subject:From:To:Content-Type; b=OGbti/D5ERNcTu+auc9tlPa39yEqauolrbrPjYp/2uTx2gbZPajpG0ZkzEazGX/ITuhu5INBsTDU996FRmD/tJkSUY1UvG/9txfMyyzo4cMBUPWCPYLM9U4q9vSgDr2guiZxGPH+ZptQXnITVHP/3H8HEpOfb1IyP9OC2cUDV1I= 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=209.85.167.199 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-f199.google.com with SMTP id 5614622812f47-4f9e7ea8bfcso468564b6e.0 for ; Mon, 05 Oct 2026 19:52:29 -0700 (PDT) X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20260707; t=1791255148; x=1791859948; 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=eKlcSjcpN68aZ4kTMBBPFgNsti4k+DS+dshMdqWyVBY=; b=0ZR6nmYgkw1UC8whBLuILg0jJus30dQPupttJ9clKFkk7xFVAdwCtXQWmRPx7wQyBy t6eX/C5PmkeIRlBkKyF2ibdFCta4VvvfpcFzO6OSVQzzFTAqlpcoyxZXtRyyVaVuutD8 cWuDXHHQHRVOrElLM4csy71jOsR8iQzpMxTNPhkD4aJrAwI7ah/owB4fwFkHy15MHwpK VhjaxvPsgcKMB6rfkcjZs0xEeL8mfAKmS0FgQm1xDouFI4X70HKdgbnqjdGFRcCfxH1a hf3EV0ZIuNvE5KEeT2FtdDcC9rSmDwGmjGSb/64LX2P+xZbsL2f9PCxOQ86ign4uo/cB H8QA== X-Forwarded-Encrypted: i=1; AKwUvBxEPwfKotvsLsT6NbbGqZBmSw+bCnNBoUvXPyBdrTAc1MTssmZYhnmpLr0jcAro32mJNWfLkFcmPnx+t7g=@vger.kernel.org X-Gm-Message-State: AFuF++n3eYDAOYGphSnFNh6eTDnR2/SscRn/kcjR8xCbMkRfYFa0tX5p oQmc5mlHsh4XnEQbM3A0fDOd+XIUuAWVl+spjqpf8K3hwm6vyf2wzu/yATMVLLeIKeIC/Fk83J2 IkqIr5fx2UacR5MtEbuVX9Zc8qc8spNIfxV9ONOcp5fTMDWWOfb7xOLuCKoM= Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 X-Received: by 2002:a05:6808:191f:b0:4f9:e0b0:37af with SMTP id 5614622812f47-4fb40c97e56mr178464b6e.27.1791255148695; Mon, 05 Oct 2026 19:52:28 -0700 (PDT) Date: Mon, 05 Oct 2026 19:52:28 -0700 X-Google-Appengine-App-Id: s~syzkaller X-Google-Appengine-App-Id-Alias: syzkaller Message-ID: <6ac4626c.9ad129c8.3858c0.0043.GAE@google.com> Subject: [syzbot] [usb?] KASAN: slab-use-after-free Write in ffs_data_clear From: syzbot To: gregkh@linuxfoundation.org, linux-kernel@vger.kernel.org, linux-usb@vger.kernel.org, syzkaller-bugs@googlegroups.com Content-Type: text/plain; charset="UTF-8" Hello, syzbot found the following issue on: HEAD commit: 9f24d789f03b Add linux-next specific files for 20261001 git tree: linux-next console output: https://syzkaller.appspot.com/x/log.txt?x=150cd3f5580000 kernel config: https://syzkaller.appspot.com/x/.config?x=c999b3b0b3b9da44 dashboard link: https://syzkaller.appspot.com/bug?extid=6227549bd2c8a1ec8ba0 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/dd8482e32335/disk-9f24d789.raw.xz vmlinux: https://storage.googleapis.com/syzbot-assets/c0d5a36cf052/vmlinux-9f24d789.xz kernel image: https://storage.googleapis.com/syzbot-assets/e5992c4e2fd4/bzImage-9f24d789.xz IMPORTANT: if you fix the issue, please add the following tag to the commit: Reported-by: syzbot+6227549bd2c8a1ec8ba0@syzkaller.appspotmail.com ================================================================== BUG: KASAN: slab-use-after-free in ffs_closed drivers/usb/gadget/function/f_fs.c:4427 [inline] BUG: KASAN: slab-use-after-free in ffs_data_clear+0x543/0x5b0 drivers/usb/gadget/function/f_fs.c:2305 Write of size 1 at addr ffff8880237b1e4a by task syz-executor/11910 CPU: 0 UID: 0 PID: 11910 Comm: syz-executor Tainted: G L Y syzkaller #0 PREEMPT(full) Tainted: [L]=SOFTLOCKUP, [Y]=FORCED_BIND 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 ffs_closed drivers/usb/gadget/function/f_fs.c:4427 [inline] ffs_data_clear+0x543/0x5b0 drivers/usb/gadget/function/f_fs.c:2305 ffs_data_reset drivers/usb/gadget/function/f_fs.c:2336 [inline] ffs_fs_kill_sb+0x84/0x370 drivers/usb/gadget/function/f_fs.c:2180 deactivate_locked_super+0xbe/0x110 fs/super.c:586 cleanup_mnt+0x3d3/0x460 fs/namespace.c:1329 task_work_run+0x1d9/0x260 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+0x204/0x770 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:343 [inline] do_syscall_64+0x328/0x520 arch/x86/entry/syscall_64.c:89 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f0c0c99f397 Code: a2 c7 05 5c 43 25 00 00 00 00 00 eb 96 e8 e1 12 00 00 90 31 f6 e9 09 00 00 00 66 0f 1f 84 00 00 00 00 00 b8 a6 00 00 00 0f 05 <48> 3d 00 f0 ff ff 77 01 c3 48 c7 c2 e8 ff ff ff f7 d8 64 89 02 b8 RSP: 002b:00007ffcc71a0748 EFLAGS: 00000246 ORIG_RAX: 00000000000000a6 RAX: 0000000000000000 RBX: 0000000000000000 RCX: 00007f0c0c99f397 RDX: 0000000000000000 RSI: 0000000000000009 RDI: 00007ffcc71a0800 RBP: 00007ffcc71a0800 R08: 00007ffcc71a1800 R09: 00000000ffffffff R10: 0000000000000000 R11: 0000000000000246 R12: 00007ffcc71a1890 R13: 00007f0c0ca344bb R14: 00000000000ca529 R15: 00007ffcc71a18d0 Allocated by task 17405: kasan_save_stack mm/kasan/common.c:57 [inline] kasan_save_track+0x3e/0x80 mm/kasan/common.c:78 poison_kmalloc_redzone mm/kasan/common.c:409 [inline] __kasan_kmalloc+0x93/0xb0 mm/kasan/common.c:426 kasan_kmalloc include/linux/kasan.h:263 [inline] __kmalloc_cache_noprof+0x31c/0x600 mm/slub.c:5680 _kmalloc_noprof include/linux/slab.h:991 [inline] _kzalloc_noprof include/linux/slab.h:1312 [inline] _ffs_alloc_dev drivers/usb/gadget/function/f_fs.c:4276 [inline] ffs_alloc_inst+0x152/0x310 drivers/usb/gadget/function/f_fs.c:4176 try_get_usb_function_instance drivers/usb/gadget/functions.c:28 [inline] usb_get_function_instance+0xe3/0x2f0 drivers/usb/gadget/functions.c:44 function_make+0x127/0x360 drivers/usb/gadget/configfs.c:626 configfs_mkdir+0x4f6/0x9e0 fs/configfs/dir.c:1369 vfs_mkdir+0x40e/0x630 fs/namei.c:5423 filename_mkdirat+0x285/0x510 fs/namei.c:5456 __do_sys_mkdirat fs/namei.c:5477 [inline] __se_sys_mkdirat+0x35/0x150 fs/namei.c:5474 do_syscall_x64 arch/x86/entry/syscall_64.c:61 [inline] do_syscall_64+0x166/0x520 arch/x86/entry/syscall_64.c:84 entry_SYSCALL_64_after_hwframe+0x77/0x7f Freed by task 17408: 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:264 [inline] __kasan_slab_free+0x5c/0x80 mm/kasan/common.c:296 kasan_slab_free include/linux/kasan.h:235 [inline] slab_free_hook mm/slub.c:2780 [inline] slab_free mm/slub.c:6630 [inline] kfree+0x1c5/0x650 mm/slub.c:6923 _ffs_free_dev drivers/usb/gadget/function/f_fs.c:4336 [inline] ffs_free_inst+0x233/0x2c0 drivers/usb/gadget/function/f_fs.c:4152 usb_put_function_instance+0x95/0xc0 drivers/usb/gadget/functions.c:77 config_item_cleanup fs/configfs/item.c:128 [inline] config_item_release+0x13a/0x2d0 fs/configfs/item.c:137 configfs_rmdir+0x885/0x950 fs/configfs/dir.c:1580 vfs_rmdir+0x3e6/0x6a0 fs/namei.c:5528 filename_rmdir+0x292/0x520 fs/namei.c:5585 __do_sys_rmdir fs/namei.c:5608 [inline] __se_sys_rmdir+0x2e/0x140 fs/namei.c:5605 do_syscall_x64 arch/x86/entry/syscall_64.c:61 [inline] do_syscall_64+0x166/0x520 arch/x86/entry/syscall_64.c:84 entry_SYSCALL_64_after_hwframe+0x77/0x7f The buggy address belongs to the object at ffff8880237b1e00 which belongs to the cache kmalloc-128 of size 128 The buggy address is located 74 bytes inside of freed 128-byte region [ffff8880237b1e00, ffff8880237b1e80) The buggy address belongs to the physical page: page: refcount:0 mapcount:0 mapping:0000000000000000 index:0xffff8880237b1d00 pfn:0x237b1 flags: 0xfff00000000200(workingset|node=0|zone=1|lastcpupid=0x7ff) page_type: f5(slab) raw: 00fff00000000200 ffff88801b041a00 ffffea0001dd3110 ffffea0001eb1c10 raw: ffff8880237b1d00 000000000010000f 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 5624, tgid 5624 (syz-executor), ts 199870517782 set_page_owner include/linux/page_owner.h:33 [inline] post_alloc_hook+0x1f9/0x250 mm/page_alloc.c:1854 prep_new_page mm/page_alloc.c:1862 [inline] get_page_from_freelist+0x220f/0x2280 mm/page_alloc.c:3933 __alloc_frozen_pages_noprof+0x1fc/0x400 mm/page_alloc.c:5468 alloc_slab_page mm/slub.c:3384 [inline] allocate_slab+0x7d/0x5e0 mm/slub.c:3499 new_slab mm/slub.c:3550 [inline] refill_objects+0x2d5/0x350 mm/slub.c:7539 refill_sheaf mm/slub.c:2917 [inline] __pcs_replace_empty_main+0x2c8/0x6c0 mm/slub.c:4811 alloc_from_pcs mm/slub.c:4887 [inline] slab_alloc_node mm/slub.c:5021 [inline] __kmalloc_cache_noprof+0x396/0x600 mm/slub.c:5676 _kmalloc_noprof include/linux/slab.h:991 [inline] _kzalloc_noprof include/linux/slab.h:1312 [inline] mm_init_sched+0x56/0x350 kernel/sched/fair.c:1660 mm_alloc_sched_noprof include/linux/mm_types.h:1675 [inline] mm_init+0x8e3/0xcb0 kernel/fork.c:1143 dup_mm kernel/fork.c:1538 [inline] copy_mm+0xfc/0x470 kernel/fork.c:1594 copy_process+0x1ea2/0x4430 kernel/fork.c:2310 kernel_clone+0x2d7/0x940 kernel/fork.c:2774 __do_sys_clone kernel/fork.c:2916 [inline] __se_sys_clone kernel/fork.c:2900 [inline] __x64_sys_clone+0x1b6/0x230 kernel/fork.c:2900 do_syscall_x64 arch/x86/entry/syscall_64.c:61 [inline] do_syscall_64+0x166/0x520 arch/x86/entry/syscall_64.c:84 entry_SYSCALL_64_after_hwframe+0x77/0x7f page last free pid 5624 tgid 5624 ts 199869898357 stack trace: reset_page_owner include/linux/page_owner.h:26 [inline] __free_pages_prepare mm/page_alloc.c:1401 [inline] free_pages_prepare+0x9eb/0xaf0 mm/page_alloc.c:1446 __free_contig_range_common+0x174/0x340 mm/page_alloc.c:7090 __free_contig_range mm/page_alloc.c:7135 [inline] free_pages_bulk+0x48/0x120 mm/page_alloc.c:5354 vm_area_free_pages mm/vmalloc.c:3505 [inline] vfree+0x22c/0x490 mm/vmalloc.c:3554 __do_replace+0x850/0x9a0 net/ipv6/netfilter/ip6_tables.c:1110 do_replace net/ipv6/netfilter/ip6_tables.c:1161 [inline] do_ip6t_set_ctl+0xb45/0xe30 net/ipv6/netfilter/ip6_tables.c:1648 nf_setsockopt+0x26f/0x290 net/netfilter/nf_sockopt.c:101 do_sock_setsockopt+0x17c/0x1b0 net/socket.c:2399 __sys_setsockopt net/socket.c:2424 [inline] __do_sys_setsockopt net/socket.c:2430 [inline] __se_sys_setsockopt net/socket.c:2427 [inline] __x64_sys_setsockopt+0x13d/0x1b0 net/socket.c:2427 do_syscall_x64 arch/x86/entry/syscall_64.c:61 [inline] do_syscall_64+0x166/0x520 arch/x86/entry/syscall_64.c:84 entry_SYSCALL_64_after_hwframe+0x77/0x7f Memory state around the buggy address: ffff8880237b1d00: fa fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff8880237b1d80: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc >ffff8880237b1e00: fa fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ^ ffff8880237b1e80: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ffff8880237b1f00: 00 00 00 00 00 00 00 00 00 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