syzbot has found a reproducer for the following issue on: HEAD commit: 72374d71c315 Merge tag 'pull-sysfs-annotation-fix' of git:.. git tree: upstream console output: https://syzkaller.appspot.com/x/log.txt?x=1391f7cb180000 kernel config: https://syzkaller.appspot.com/x/.config?x=2881987c7d7b722d dashboard link: https://syzkaller.appspot.com/bug?extid=83845bb93916bb30c048 compiler: arm-linux-gnueabi-gcc (Debian 12.2.0-14) 12.2.0, GNU ld (GNU Binutils for Debian) 2.40 userspace arch: arm syz repro: https://syzkaller.appspot.com/x/repro.syz?x=147d8f6d180000 C reproducer: https://syzkaller.appspot.com/x/repro.c?x=14fb0bf3180000 Downloadable assets: disk image (non-bootable): https://storage.googleapis.com/syzbot-assets/8ead8862021c/non_bootable_disk-72374d71.raw.xz vmlinux: https://storage.googleapis.com/syzbot-assets/664d9f3a4812/vmlinux-72374d71.xz kernel image: https://storage.googleapis.com/syzbot-assets/767ecc5e77ad/zImage-72374d71.xz IMPORTANT: if you fix the issue, please add the following tag to the commit: Reported-by: syzbot+83845bb93916bb30c048@xxxxxxxxxxxxxxxxxxxxxxxxx cdc_ncm 1-1:1.0 usb0: register 'cdc_ncm' at usb-dummy_hcd.0-1, CDC NCM (NO ZLP), 42:42:42:42:42:42 usb 1-1: USB disconnect, device number 10 cdc_ncm 1-1:1.0 usb0: unregister 'cdc_ncm' usb-dummy_hcd.0-1, CDC NCM (NO ZLP) ------------[ cut here ]------------ WARNING: CPU: 0 PID: 45 at lib/debugobjects.c:514 debug_print_object+0xc4/0xd8 lib/debugobjects.c:514 ODEBUG: free active (active state 0) object: 841377ac object type: work_struct hint: usbnet_deferred_kevent+0x0/0x388 drivers/net/usb/usbnet.c:630 Modules linked in: Kernel panic - not syncing: kernel: panic_on_warn set ... CPU: 0 PID: 45 Comm: kworker/0:2 Not tainted 6.9.0-rc3-syzkaller #0 Hardware name: ARM-Versatile Express Workqueue: usb_hub_wq hub_event Call trace: [<818a18bc>] (dump_backtrace) from [<818a19b8>] (show_stack+0x18/0x1c arch/arm/kernel/traps.c:256) r7:00000000 r6:82622e44 r5:00000000 r4:81fcea10 [<818a19a0>] (show_stack) from [<818bf0e0>] (__dump_stack lib/dump_stack.c:88 [inline]) [<818a19a0>] (show_stack) from [<818bf0e0>] (dump_stack_lvl+0x54/0x7c lib/dump_stack.c:114) [<818bf08c>] (dump_stack_lvl) from [<818bf120>] (dump_stack+0x18/0x1c lib/dump_stack.c:123) r5:00000000 r4:8285ad18 [<818bf108>] (dump_stack) from [<818a2460>] (panic+0x120/0x358 kernel/panic.c:348) [<818a2340>] (panic) from [<8024390c>] (check_panic_on_warn kernel/panic.c:241 [inline]) [<818a2340>] (panic) from [<8024390c>] (print_tainted+0x0/0xa0 kernel/panic.c:236) r3:8260c584 r2:00000001 r1:81fb773c r0:81fbf2e0 r7:8080a0d0 [<80243898>] (check_panic_on_warn) from [<80243b00>] (__warn+0x7c/0x180 kernel/panic.c:694) [<80243a84>] (__warn) from [<80243dec>] (warn_slowpath_fmt+0x1e8/0x1f4 kernel/panic.c:727) r8:00000009 r7:8201b320 r6:df919a7c r5:82fd3c00 r4:00000000 [<80243c08>] (warn_slowpath_fmt) from [<8080a0d0>] (debug_print_object+0xc4/0xd8 lib/debugobjects.c:514) r10:00000005 r9:84137000 r8:81a02b44 r7:82043274 r6:828be454 r5:df919b24 r4:8260ce18 [<8080a00c>] (debug_print_object) from [<8080b968>] (__debug_check_no_obj_freed lib/debugobjects.c:989 [inline]) [<8080a00c>] (debug_print_object) from [<8080b968>] (debug_check_no_obj_freed+0x254/0x2a0 lib/debugobjects.c:1019) r8:84137800 r7:841377ac r6:00000100 r5:00000003 r4:00000000 [<8080b714>] (debug_check_no_obj_freed) from [<804b2820>] (slab_free_hook mm/slub.c:2078 [inline]) [<8080b714>] (debug_check_no_obj_freed) from [<804b2820>] (slab_free mm/slub.c:4280 [inline]) [<8080b714>] (debug_check_no_obj_freed) from [<804b2820>] (kfree+0x1a0/0x334 mm/slub.c:4390) r10:82775a28 r9:84534880 r8:84137000 r7:8045a920 r6:82c023c0 r5:dde8bac0 r4:84137000 [<804b2680>] (kfree) from [<8045a920>] (kvfree+0x2c/0x30 mm/util.c:680) r10:82775a28 r9:84534880 r8:84137000 r7:00000000 r6:844b9480 r5:84652200 r4:84137000 [<8045a8f4>] (kvfree) from [<813dbb0c>] (netdev_freemem+0x1c/0x20 net/core/dev.c:10797) r5:84652200 r4:84137000 [<813dbaf0>] (netdev_freemem) from [<81416b74>] (netdev_release+0x2c/0x34 net/core/net-sysfs.c:2031) [<81416b48>] (netdev_release) from [<80a404e0>] (device_release+0x38/0xa8 drivers/base/core.c:2580) r5:84652200 r4:841373b8 [<80a404a8>] (device_release) from [<8187b820>] (kobject_cleanup lib/kobject.c:689 [inline]) [<80a404a8>] (device_release) from [<8187b820>] (kobject_release lib/kobject.c:720 [inline]) [<80a404a8>] (device_release) from [<8187b820>] (kref_put include/linux/kref.h:65 [inline]) [<80a404a8>] (device_release) from [<8187b820>] (kobject_put+0xc8/0x1f8 lib/kobject.c:737) r5:81b489c4 r4:841373b8 [<8187b758>] (kobject_put) from [<80a40768>] (put_device+0x18/0x1c drivers/base/core.c:3828) r7:84536800 r6:8413710c r5:84137000 r4:00000000 [<80a40750>] (put_device) from [<813cce58>] (free_netdev+0x108/0x188 net/core/dev.c:10993) [<813ccd50>] (free_netdev) from [<80d10be0>] (usbnet_disconnect+0xac/0xf0 drivers/net/usb/usbnet.c:1636) r6:84137774 r5:84137660 r4:00000000 [<80d10b34>] (usbnet_disconnect) from [<80d6bcc4>] (usb_unbind_interface+0x84/0x2c4 drivers/usb/core/driver.c:461) r8:00000044 r7:84536830 r6:82775a28 r5:00000000 r4:84536800 [<80d6bc40>] (usb_unbind_interface) from [<80a485bc>] (device_remove drivers/base/dd.c:568 [inline]) [<80d6bc40>] (usb_unbind_interface) from [<80a485bc>] (device_remove+0x64/0x6c drivers/base/dd.c:560) r10:84534880 r9:828eed04 r8:00000044 r7:84536874 r6:82775a28 r5:00000000 r4:84536830 [<80a48558>] (device_remove) from [<80a49ad4>] (__device_release_driver drivers/base/dd.c:1270 [inline]) [<80a48558>] (device_remove) from [<80a49ad4>] (device_release_driver_internal+0x18c/0x200 drivers/base/dd.c:1293) r5:00000000 r4:84536830 [<80a49948>] (device_release_driver_internal) from [<80a49b60>] (device_release_driver+0x18/0x1c drivers/base/dd.c:1316) r9:828eed04 r8:82f51a40 r7:82f51a38 r6:82f51a0c r5:84536830 r4:82f51a30 [<80a49b48>] (device_release_driver) from [<80a47c60>] (bus_remove_device+0xcc/0x120 drivers/base/bus.c:574) [<80a47b94>] (bus_remove_device) from [<80a41ce4>] (device_del+0x15c/0x3bc drivers/base/core.c:3909) r9:828eed04 r8:84536800 r7:82fd3c00 r6:843cc208 r5:04208060 r4:84536830 [<80a41b88>] (device_del) from [<80d69720>] (usb_disable_device+0xdc/0x1f0 drivers/usb/core/message.c:1418) r10:00000000 r9:00000000 r8:84536800 r7:84534800 r6:843cc208 r5:00000001 r4:00000038 [<80d69644>] (usb_disable_device) from [<80d5e58c>] (usb_disconnect+0xec/0x29c drivers/usb/core/hub.c:2305) r10:00000001 r9:8464e800 r8:845348c4 r7:83e1a400 r6:84534880 r5:84534800 r4:60000013 [<80d5e4a0>] (usb_disconnect) from [<80d6113c>] (hub_port_connect drivers/usb/core/hub.c:5361 [inline]) [<80d5e4a0>] (usb_disconnect) from [<80d6113c>] (hub_port_connect_change drivers/usb/core/hub.c:5661 [inline]) [<80d5e4a0>] (usb_disconnect) from [<80d6113c>] (port_event drivers/usb/core/hub.c:5821 [inline]) [<80d5e4a0>] (usb_disconnect) from [<80d6113c>] (hub_event+0xd78/0x194c drivers/usb/core/hub.c:5903) r10:00000001 r9:00000101 r8:83c48b00 r7:84534800 r6:83e19c00 r5:83e1a610 r4:00000001 [<80d603c4>] (hub_event) from [<8026660c>] (process_one_work+0x1b8/0x508 kernel/workqueue.c:3254) r10:82e65805 r9:82fd3c00 r8:00000080 r7:dddd00c0 r6:82e65800 r5:83c48b00 r4:82f57a80 [<80266454>] (process_one_work) from [<80267330>] (process_scheduled_works kernel/workqueue.c:3335 [inline]) [<80266454>] (process_one_work) from [<80267330>] (worker_thread+0x1ec/0x418 kernel/workqueue.c:3416) r10:82fd3c00 r9:82f57aac r8:61c88647 r7:dddd00e0 r6:82604d40 r5:dddd00c0 r4:82f57a80 [<80267144>] (worker_thread) from [<80270044>] (kthread+0x104/0x134 kernel/kthread.c:388) r10:00000000 r9:df839e90 r8:82f59740 r7:82f57a80 r6:80267144 r5:82fd3c00 r4:82f59540 [<8026ff40>] (kthread) from [<80200104>] (ret_from_fork+0x14/0x30 arch/arm/kernel/entry-common.S:134) Exception stack(0xdf919fb0 to 0xdf919ff8) 9fa0: 00000000 00000000 00000000 00000000 9fc0: 00000000 00000000 00000000 00000000 00000000 00000000 00000000 00000000 9fe0: 00000000 00000000 00000000 00000000 00000013 00000000 r9:00000000 r8:00000000 r7:00000000 r6:00000000 r5:8026ff40 r4:82f59540 Rebooting in 86400 seconds.. --- If you want syzbot to run the reproducer, reply with: #syz test: git://repo/address.git branch-or-commit-hash If you attach or paste a git patch, syzbot will apply it before testing.