================================================================== BUG: KASAN: use-after-free in kernfs_root fs/kernfs/kernfs-internal.h:66 [inline] BUG: KASAN: use-after-free in kernfs_next_descendant_post+0x2cd/0x2f0 fs/kernfs/dir.c:1281 Read of size 8 at addr ffff8880224a4898 by task kworker/2:15/5504 CPU: 2 PID: 5504 Comm: kworker/2:15 Not tainted 5.18.0-rc4-syzkaller-00083-g259b897e5a79 #0 Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.14.0-2 04/01/2014 Workqueue: events request_firmware_work_func Call Trace: __dump_stack lib/dump_stack.c:88 [inline] dump_stack_lvl+0xcd/0x134 lib/dump_stack.c:106 print_address_description.constprop.0.cold+0xeb/0x467 mm/kasan/report.c:313 print_report mm/kasan/report.c:429 [inline] kasan_report.cold+0xf4/0x1c6 mm/kasan/report.c:491 kernfs_root fs/kernfs/kernfs-internal.h:66 [inline] kernfs_next_descendant_post+0x2cd/0x2f0 fs/kernfs/dir.c:1281 kernfs_activate+0x97/0x240 fs/kernfs/dir.c:1321 kernfs_add_one+0x3c6/0x550 fs/kernfs/dir.c:767 kernfs_create_dir_ns+0x18b/0x220 fs/kernfs/dir.c:1013 sysfs_create_dir_ns+0x127/0x290 fs/sysfs/dir.c:59 create_dir lib/kobject.c:63 [inline] kobject_add_internal+0x2ce/0x900 lib/kobject.c:223 kobject_add_varg lib/kobject.c:358 [inline] kobject_add+0x150/0x1c0 lib/kobject.c:410 class_dir_create_and_add drivers/base/core.c:2942 [inline] get_device_parent+0x3d7/0x590 drivers/base/core.c:2997 device_add+0x2a8/0x1e20 drivers/base/core.c:3326 fw_load_sysfs_fallback drivers/base/firmware_loader/fallback.c:512 [inline] fw_load_from_user_helper drivers/base/firmware_loader/fallback.c:588 [inline] firmware_fallback_sysfs+0x402/0xe70 drivers/base/firmware_loader/fallback.c:664 _request_firmware+0xb97/0xfe0 drivers/base/firmware_loader/main.c:774 request_firmware_work_func+0xdd/0x230 drivers/base/firmware_loader/main.c:1020 process_one_work+0x996/0x1610 kernel/workqueue.c:2289 worker_thread+0x665/0x1080 kernel/workqueue.c:2436 kthread+0x2e9/0x3a0 kernel/kthread.c:376 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:298 Allocated by task 5504: kasan_save_stack+0x1e/0x40 mm/kasan/common.c:38 kasan_set_track mm/kasan/common.c:45 [inline] set_alloc_info mm/kasan/common.c:436 [inline] __kasan_slab_alloc+0x85/0xb0 mm/kasan/common.c:469 kasan_slab_alloc include/linux/kasan.h:224 [inline] slab_post_alloc_hook mm/slab.h:749 [inline] slab_alloc mm/slab.c:3316 [inline] __kmem_cache_alloc_lru mm/slab.c:3493 [inline] kmem_cache_alloc+0x265/0x560 mm/slab.c:3513 kmem_cache_zalloc include/linux/slab.h:704 [inline] __kernfs_new_node+0xd4/0x8b0 fs/kernfs/dir.c:585 kernfs_new_node fs/kernfs/dir.c:647 [inline] kernfs_create_dir_ns+0x9c/0x220 fs/kernfs/dir.c:1003 sysfs_create_dir_ns+0x127/0x290 fs/sysfs/dir.c:59 create_dir lib/kobject.c:63 [inline] kobject_add_internal+0x2ce/0x900 lib/kobject.c:223 kobject_add_varg lib/kobject.c:358 [inline] kobject_add+0x150/0x1c0 lib/kobject.c:410 class_dir_create_and_add drivers/base/core.c:2942 [inline] get_device_parent+0x3d7/0x590 drivers/base/core.c:2997 device_add+0x2a8/0x1e20 drivers/base/core.c:3326 fw_load_sysfs_fallback drivers/base/firmware_loader/fallback.c:512 [inline] fw_load_from_user_helper drivers/base/firmware_loader/fallback.c:588 [inline] firmware_fallback_sysfs+0x402/0xe70 drivers/base/firmware_loader/fallback.c:664 _request_firmware+0xb97/0xfe0 drivers/base/firmware_loader/main.c:774 request_firmware_work_func+0xdd/0x230 drivers/base/firmware_loader/main.c:1020 process_one_work+0x996/0x1610 kernel/workqueue.c:2289 worker_thread+0x665/0x1080 kernel/workqueue.c:2436 kthread+0x2e9/0x3a0 kernel/kthread.c:376 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:298 Freed by task 5503: kasan_save_stack+0x1e/0x40 mm/kasan/common.c:38 kasan_set_track+0x21/0x30 mm/kasan/common.c:45 kasan_set_free_info+0x20/0x30 mm/kasan/generic.c:370 ____kasan_slab_free mm/kasan/common.c:366 [inline] ____kasan_slab_free+0x13d/0x180 mm/kasan/common.c:328 kasan_slab_free include/linux/kasan.h:200 [inline] __cache_free mm/slab.c:3439 [inline] kmem_cache_free.part.0+0xa9/0x240 mm/slab.c:3749 kernfs_put.part.0+0x2c4/0x540 fs/kernfs/dir.c:539 kernfs_put+0x42/0x50 fs/kernfs/dir.c:513 __kernfs_remove+0x7a3/0xb20 fs/kernfs/dir.c:1397 kernfs_remove+0x6d/0x90 fs/kernfs/dir.c:1412 sysfs_remove_dir+0xc1/0x100 fs/sysfs/dir.c:101 __kobject_del+0xe2/0x200 lib/kobject.c:588 kobject_del lib/kobject.c:611 [inline] kobject_del+0x3c/0x60 lib/kobject.c:603 device_del+0x81c/0xc80 drivers/base/core.c:3603 usb_disconnect.cold+0x4ba/0x6ec drivers/usb/core/hub.c:2254 hub_port_connect drivers/usb/core/hub.c:5207 [inline] hub_port_connect_change drivers/usb/core/hub.c:5507 [inline] port_event drivers/usb/core/hub.c:5665 [inline] hub_event+0x1e74/0x4680 drivers/usb/core/hub.c:5747 process_one_work+0x996/0x1610 kernel/workqueue.c:2289 process_scheduled_works kernel/workqueue.c:2352 [inline] worker_thread+0x854/0x1080 kernel/workqueue.c:2438 kthread+0x2e9/0x3a0 kernel/kthread.c:376 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:298 The buggy address belongs to the object at ffff8880224a4868 which belongs to the cache kernfs_node_cache of size 168 The buggy address is located 48 bytes inside of 168-byte region [ffff8880224a4868, ffff8880224a4910) The buggy address belongs to the physical page: page:ffffea0000892900 refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x224a4 flags: 0xfff00000000200(slab|node=0|zone=1|lastcpupid=0x7ff) raw: 00fff00000000200 ffffea000059be88 ffffea0000969f88 ffff888011613000 raw: 0000000000000000 ffff8880224a4040 0000000100000011 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 0x2420c0(__GFP_IO|__GFP_FS|__GFP_NOWARN|__GFP_COMP|__GFP_THISNODE), pid 5537, tgid 5535 (syz-executor.3), ts 286916199515, free_ts 251346193508 prep_new_page mm/page_alloc.c:2441 [inline] get_page_from_freelist+0xba2/0x3e00 mm/page_alloc.c:4182 __alloc_pages_slowpath.constprop.0+0x2eb/0x20e0 mm/page_alloc.c:4953 __alloc_pages+0x412/0x500 mm/page_alloc.c:5421 __alloc_pages_node include/linux/gfp.h:587 [inline] kmem_getpages mm/slab.c:1378 [inline] cache_grow_begin+0x75/0x350 mm/slab.c:2584 cache_alloc_refill+0x27f/0x380 mm/slab.c:2957 ____cache_alloc mm/slab.c:3040 [inline] ____cache_alloc mm/slab.c:3023 [inline] __do_cache_alloc mm/slab.c:3267 [inline] slab_alloc mm/slab.c:3309 [inline] __kmem_cache_alloc_lru mm/slab.c:3493 [inline] kmem_cache_alloc+0x450/0x560 mm/slab.c:3513 kmem_cache_zalloc include/linux/slab.h:704 [inline] __kernfs_new_node+0xd4/0x8b0 fs/kernfs/dir.c:585 kernfs_new_node+0x93/0x120 fs/kernfs/dir.c:647 __kernfs_create_file+0x51/0x350 fs/kernfs/file.c:982 sysfs_add_file_mode_ns+0x20f/0x3f0 fs/sysfs/file.c:294 create_files fs/sysfs/group.c:64 [inline] internal_create_group+0x322/0xb10 fs/sysfs/group.c:148 internal_create_groups.part.0+0x90/0x140 fs/sysfs/group.c:188 internal_create_groups fs/sysfs/group.c:184 [inline] sysfs_create_groups+0x25/0x50 fs/sysfs/group.c:214 device_add_groups drivers/base/core.c:2471 [inline] device_add_attrs drivers/base/core.c:2630 [inline] device_add+0x1426/0x1e20 drivers/base/core.c:3356 netdev_register_kobject+0x181/0x430 net/core/net-sysfs.c:2008 register_netdevice+0xd9d/0x15b0 net/core/dev.c:9961 page last free stack trace: reset_page_owner include/linux/page_owner.h:24 [inline] free_pages_prepare mm/page_alloc.c:1356 [inline] free_pcp_prepare+0x549/0xd20 mm/page_alloc.c:1406 free_unref_page_prepare mm/page_alloc.c:3328 [inline] free_unref_page+0x19/0x6a0 mm/page_alloc.c:3423 slab_destroy mm/slab.c:1630 [inline] slabs_destroy+0x89/0xc0 mm/slab.c:1650 drain_array+0x93/0xa0 mm/slab.c:3985 cache_reap+0x188/0x290 mm/slab.c:4034 process_one_work+0x996/0x1610 kernel/workqueue.c:2289 worker_thread+0x665/0x1080 kernel/workqueue.c:2436 kthread+0x2e9/0x3a0 kernel/kthread.c:376 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:298 Memory state around the buggy address: ffff8880224a4780: fa fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff8880224a4800: fb fb fb fb fb fc fc fc fc fc fc fc fc fa fb fb >ffff8880224a4880: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ^ ffff8880224a4900: fb fb fc fc fc fc fc fc fc fc 00 00 00 00 00 00 ffff8880224a4980: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 fc ==================================================================