From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mail-ot1-f80.google.com (mail-ot1-f80.google.com [209.85.210.80]) (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 F42011EA65 for ; Wed, 8 Jul 2026 00:07:21 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=209.85.210.80 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1783469249; cv=none; b=kKQp2q4GaCzZT5vk6bw7KHnyH7SOP7uCf4Surq5HgerG4STOflSgi+FMPGrWYlMJj5to219RYCOE7IqNDKegoH9cMBWv39d902+6+TE5eKKoyV20KvT2qGZcK0RpFemTesi4usp5sP64q/QxTHORakWeyQKazPbFsXA9RRjdkiA= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1783469249; c=relaxed/simple; bh=hRVTaqV7IFkG8iYkyaLF1pb3XueR/oVFJP+zP4x0Go0=; h=MIME-Version:Date:Message-ID:Subject:From:To:Content-Type; b=VO4NmBjAdARZX5K1DQ1HB7QHlqGzxWLo6rqBZnUWHjS0dUW2d/pl1xctvRTBC3tp2r3Jyrz0cg33vlHNNRt147nPScLaMvNo54TIV+KXJGsjr7idqmO/tCsJ+N64NF/IpjKuoRLX7QEODaG6DXIXWMTLSLXQRdvpTxZQn8zX4vY= 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=209.85.210.80 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-f80.google.com with SMTP id 46e09a7af769-7e9fbcd3a0eso161616a34.1 for ; Tue, 07 Jul 2026 17:07:21 -0700 (PDT) X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20251104; t=1783469241; x=1784074041; 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=SGGxjstucQLMLosSH6c+Jj3dXhkAS/EZBfAWGxs2VBQ=; b=bfi9gXzxPbZYxzTic9ovee+faf7uPp5HybcrHhqB9UnDRIr6hTVSrScjvAq/hNTEwh hl9HZh+/7BsLRaZkBpZm8VYT8QzmQcnQi9nQmom9mS7PXwLeTedaEob9v1QrEi4dEcFv 0/Pl/mxqS3dz+P6pqvWPwy9ltox0LCsxxCpuuNT3+8eu1hjnWhwQv5K0xz+1faombcaN K7qWkMxj9tUxCY+4wNR48SdeQ1ngUiDUz3YdRcuYUyaF3hogz3e4kyCONuscvVBpKAAH zDFkxLoWzI6yb2YjgdF7bd1VCXwDROZ5GP9TRKcXWqBzWzbVJxQoaUqaSJ+tho16QW8N c9oA== X-Forwarded-Encrypted: i=1; AFNElJ+xic9P9Z6rrmco/3mTYllQOjue8dyJAbL/Uf2EHaRj+a2Waaq/KP6RNXimrCpGb9SeKN99rsNsdaip5hc=@vger.kernel.org X-Gm-Message-State: AOJu0YxZdiPOsyCCjEcpkkWbufEfrJr3OZd6NVcKE6olUeKh1d7lSRGp yFFXWFzLtyPL91y+dOuYm+AFG8FSPDX3cDpKoQejZn/41My2lKN+dtroQiuXnNra3AcgBPfaReU UcGO8LU6Ixc+sx+F6WCgXLRQlcQoVfk4JEm7QkgckO2OgQC1pGJemublmLX8= Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 X-Received: by 2002:a05:6808:4706:b0:49e:d43f:1b93 with SMTP id 5614622812f47-4a2021fa2e1mr121247b6e.13.1783469240942; Tue, 07 Jul 2026 17:07:20 -0700 (PDT) Date: Tue, 07 Jul 2026 17:07:20 -0700 X-Google-Appengine-App-Id: s~syzkaller X-Google-Appengine-App-Id-Alias: syzkaller Message-ID: <6a4d94b8.c76b52dc.34afef.0015.GAE@google.com> Subject: [syzbot] [kernfs?] KASAN: slab-use-after-free Read in kernfs_get (4) From: syzbot To: driver-core@lists.linux.dev, gregkh@linuxfoundation.org, linux-kernel@vger.kernel.org, syzkaller-bugs@googlegroups.com, tj@kernel.org Content-Type: text/plain; charset="UTF-8" Hello, syzbot found the following issue on: HEAD commit: d2c9a99135da Merge tag 'device-id-rework' of git://git.ker.. git tree: upstream console output: https://syzkaller.appspot.com/x/log.txt?x=16dd80d6580000 kernel config: https://syzkaller.appspot.com/x/.config?x=5c4196ba0e33631d dashboard link: https://syzkaller.appspot.com/bug?extid=61d22228f1d777d4a5c1 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/cb55a636c1b2/disk-d2c9a991.raw.xz vmlinux: https://storage.googleapis.com/syzbot-assets/e4bdf13aafbf/vmlinux-d2c9a991.xz kernel image: https://storage.googleapis.com/syzbot-assets/8388280f1b6e/bzImage-d2c9a991.xz IMPORTANT: if you fix the issue, please add the following tag to the commit: Reported-by: syzbot+61d22228f1d777d4a5c1@syzkaller.appspotmail.com usb 4-1: Direct firmware load for ueagle-atm/eagleI.fw failed with error -2 usb 4-1: Falling back to sysfs fallback for: ueagle-atm/eagleI.fw ================================================================== BUG: KASAN: slab-use-after-free in instrument_atomic_read include/linux/instrumented.h:82 [inline] BUG: KASAN: slab-use-after-free in atomic_read include/linux/atomic/atomic-instrumented.h:32 [inline] BUG: KASAN: slab-use-after-free in kernfs_get+0x20/0x90 fs/kernfs/dir.c:560 Read of size 4 at addr ffff8880338825a0 by task kworker/0:0/9 CPU: 0 UID: 0 PID: 9 Comm: kworker/0:0 Tainted: G L syzkaller #0 PREEMPT(full) Tainted: [L]=SOFTLOCKUP Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/09/2026 Workqueue: events request_firmware_work_func 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 check_region_inline mm/kasan/generic.c:-1 [inline] kasan_check_range+0x264/0x2c0 mm/kasan/generic.c:200 instrument_atomic_read include/linux/instrumented.h:82 [inline] atomic_read include/linux/atomic/atomic-instrumented.h:32 [inline] kernfs_get+0x20/0x90 fs/kernfs/dir.c:560 sysfs_get include/linux/sysfs.h:802 [inline] create_dir lib/kobject.c:89 [inline] kobject_add_internal+0x6b9/0xcd0 lib/kobject.c:240 kobject_add_varg lib/kobject.c:374 [inline] kobject_add+0x163/0x240 lib/kobject.c:426 class_dir_create_and_add drivers/base/core.c:3300 [inline] get_device_parent+0x316/0x3a0 drivers/base/core.c:3351 device_add+0x2d4/0xb80 drivers/base/core.c:3681 fw_load_sysfs_fallback drivers/base/firmware_loader/fallback.c:86 [inline] fw_load_from_user_helper drivers/base/firmware_loader/fallback.c:162 [inline] firmware_fallback_sysfs+0x2dd/0xa40 drivers/base/firmware_loader/fallback.c:238 _request_firmware+0x1049/0x1780 drivers/base/firmware_loader/main.c:898 request_firmware_work_func+0xac/0x2d0 drivers/base/firmware_loader/main.c:1162 process_one_work kernel/workqueue.c:3322 [inline] process_scheduled_works+0xa8e/0x14e0 kernel/workqueue.c:3405 worker_thread+0xa47/0xfb0 kernel/workqueue.c:3486 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 Allocated by task 9: 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:4612 [inline] slab_alloc_node mm/slub.c:4945 [inline] kmem_cache_alloc_noprof+0x2a0/0x5f0 mm/slub.c:4959 __kernfs_new_node+0xe6/0x980 fs/kernfs/dir.c:665 kernfs_new_node fs/kernfs/dir.c:751 [inline] kernfs_create_dir_ns+0xfe/0x230 fs/kernfs/dir.c:1120 sysfs_create_dir_ns+0x12f/0x2a0 fs/sysfs/dir.c:59 create_dir lib/kobject.c:73 [inline] kobject_add_internal+0x622/0xcd0 lib/kobject.c:240 kobject_add_varg lib/kobject.c:374 [inline] kobject_add+0x163/0x240 lib/kobject.c:426 class_dir_create_and_add drivers/base/core.c:3300 [inline] get_device_parent+0x316/0x3a0 drivers/base/core.c:3351 device_add+0x2d4/0xb80 drivers/base/core.c:3681 fw_load_sysfs_fallback drivers/base/firmware_loader/fallback.c:86 [inline] fw_load_from_user_helper drivers/base/firmware_loader/fallback.c:162 [inline] firmware_fallback_sysfs+0x2dd/0xa40 drivers/base/firmware_loader/fallback.c:238 _request_firmware+0x1049/0x1780 drivers/base/firmware_loader/main.c:898 request_firmware_work_func+0xac/0x2d0 drivers/base/firmware_loader/main.c:1162 process_one_work kernel/workqueue.c:3322 [inline] process_scheduled_works+0xa8e/0x14e0 kernel/workqueue.c:3405 worker_thread+0xa47/0xfb0 kernel/workqueue.c:3486 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 Freed by task 15: 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:2705 [inline] slab_free mm/slub.c:6405 [inline] kmem_cache_free+0x182/0x650 mm/slub.c:6532 rcu_do_batch kernel/rcu/tree.c:2645 [inline] rcu_core+0x78b/0x10a0 kernel/rcu/tree.c:2897 handle_softirqs+0x225/0x840 kernel/softirq.c:622 run_ksoftirqd+0x36/0x60 kernel/softirq.c:1076 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 kernfs_put+0x622/0x820 fs/kernfs/dir.c:618 __kernfs_remove+0x69a/0x8e0 fs/kernfs/dir.c:1603 kernfs_remove+0x4c/0x80 fs/kernfs/dir.c:1624 __kobject_del+0xe0/0x310 lib/kobject.c:604 kobject_del+0x45/0x60 lib/kobject.c:627 device_del+0x772/0x8f0 drivers/base/core.c:3981 usb_disconnect+0x630/0x9a0 drivers/usb/core/hub.c:2376 hub_port_connect drivers/usb/core/hub.c:5407 [inline] hub_port_connect_change drivers/usb/core/hub.c:5707 [inline] port_event drivers/usb/core/hub.c:5871 [inline] hub_event+0x1bbb/0x4d30 drivers/usb/core/hub.c:5953 process_one_work kernel/workqueue.c:3322 [inline] process_scheduled_works+0xa8e/0x14e0 kernel/workqueue.c:3405 worker_thread+0xa47/0xfb0 kernel/workqueue.c:3486 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 The buggy address belongs to the object at ffff8880338825a0 which belongs to the cache kernfs_node_cache of size 176 The buggy address is located 0 bytes inside of freed 176-byte region [ffff8880338825a0, ffff888033882650) The buggy address belongs to the physical page: page: refcount:0 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x33882 flags: 0xfff00000000000(node=0|zone=1|lastcpupid=0x7ff) page_type: f5(slab) raw: 00fff00000000000 ffff888140415280 dead000000000100 dead000000000122 raw: 0000000000000000 0000000800110011 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 8130, tgid 8129 (syz.0.763), ts 244206391995, free_ts 244188026758 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+0x21fa/0x2270 mm/page_alloc.c:3946 __alloc_frozen_pages_noprof+0x18d/0x380 mm/page_alloc.c:5304 alloc_slab_page mm/slub.c:3294 [inline] allocate_slab+0x79/0x5e0 mm/slub.c:3408 new_slab mm/slub.c:3454 [inline] refill_objects+0x2d5/0x350 mm/slub.c:7338 refill_sheaf mm/slub.c:2832 [inline] __pcs_replace_empty_main+0x2bf/0x6b0 mm/slub.c:4703 alloc_from_pcs mm/slub.c:4801 [inline] slab_alloc_node mm/slub.c:4933 [inline] kmem_cache_alloc_noprof+0x382/0x5f0 mm/slub.c:4959 __kernfs_new_node+0xe6/0x980 fs/kernfs/dir.c:665 kernfs_new_node fs/kernfs/dir.c:751 [inline] kernfs_create_dir_ns+0xfe/0x230 fs/kernfs/dir.c:1120 sysfs_create_dir_ns+0x12f/0x2a0 fs/sysfs/dir.c:59 create_dir lib/kobject.c:73 [inline] kobject_add_internal+0x622/0xcd0 lib/kobject.c:240 kobject_add_varg lib/kobject.c:374 [inline] kobject_init_and_add+0x12b/0x1a0 lib/kobject.c:457 rx_queue_add_kobject net/core/net-sysfs.c:1239 [inline] net_rx_queue_update_kobjects+0x247/0x780 net/core/net-sysfs.c:1301 register_queue_kobjects net/core/net-sysfs.c:2093 [inline] netdev_register_kobject+0x21f/0x310 net/core/net-sysfs.c:2341 register_netdevice+0x1433/0x1eb0 net/core/dev.c:11440 register_netdev+0x40/0x60 net/core/dev.c:11556 page last free pid 23 tgid 23 stack trace: reset_page_owner include/linux/page_owner.h:25 [inline] __free_pages_prepare mm/page_alloc.c:1406 [inline] __free_frozen_pages+0xc1e/0xd10 mm/page_alloc.c:2950 __tlb_remove_table_free mm/mmu_gather.c:228 [inline] tlb_remove_table_rcu+0x85/0x100 mm/mmu_gather.c:291 rcu_do_batch kernel/rcu/tree.c:2645 [inline] rcu_core+0x78b/0x10a0 kernel/rcu/tree.c:2897 handle_softirqs+0x225/0x840 kernel/softirq.c:622 run_ksoftirqd+0x36/0x60 kernel/softirq.c:1076 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: ffff888033882480: fc fc fc fc fc fc fa fb fb fb fb fb fb fb fb fb ffff888033882500: fb fb fb fb fb fb fb fb fb fb fb fb fc fc fc fc >ffff888033882580: fc fc fc fc fa fb fb fb fb fb fb fb fb fb fb fb ^ ffff888033882600: fb fb fb fb fb fb fb fb fb fb fc fc fc fc fc fc ffff888033882680: fc fc fa fb fb fb fb fb fb fb fb fb fb fb fb fb ================================================================== --- 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