================================================================== BUG: KASAN: use-after-free in kernfs_root fs/kernfs/kernfs-internal.h:66 [inline] BUG: KASAN: use-after-free in kernfs_add_one+0x4b4/0x4f0 fs/kernfs/dir.c:791 Read of size 8 at addr ffff888038c83eb0 by task kworker/0:6/2569 CPU: 0 PID: 2569 Comm: kworker/0:6 Not tainted 6.2.0-rc7-syzkaller-00135-g38c1e0c65865 #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/21/2023 Workqueue: events request_firmware_work_func Call Trace: __dump_stack lib/dump_stack.c:88 [inline] dump_stack_lvl+0xd1/0x138 lib/dump_stack.c:106 print_address_description mm/kasan/report.c:306 [inline] print_report+0x15e/0x45d mm/kasan/report.c:417 kasan_report+0xbf/0x1f0 mm/kasan/report.c:517 kernfs_root fs/kernfs/kernfs-internal.h:66 [inline] kernfs_add_one+0x4b4/0x4f0 fs/kernfs/dir.c:791 kernfs_create_dir_ns+0x18f/0x230 fs/kernfs/dir.c:1042 sysfs_create_dir_ns+0x12b/0x290 fs/sysfs/dir.c:59 create_dir lib/kobject.c:63 [inline] kobject_add_internal+0x2c9/0x8f0 lib/kobject.c:223 kobject_add_varg lib/kobject.c:358 [inline] kobject_add+0x154/0x1c0 lib/kobject.c:410 class_dir_create_and_add drivers/base/core.c:3016 [inline] get_device_parent+0x3d7/0x590 drivers/base/core.c:3071 device_add+0x2ae/0x1e90 drivers/base/core.c:3400 fw_load_sysfs_fallback drivers/base/firmware_loader/fallback.c:82 [inline] fw_load_from_user_helper drivers/base/firmware_loader/fallback.c:158 [inline] firmware_fallback_sysfs+0x2d9/0xba0 drivers/base/firmware_loader/fallback.c:234 _request_firmware+0xbcf/0x1190 drivers/base/firmware_loader/main.c:856 request_firmware_work_func+0xe1/0x240 drivers/base/firmware_loader/main.c:1105 process_one_work+0x9bf/0x1710 kernel/workqueue.c:2289 worker_thread+0x669/0x1090 kernel/workqueue.c:2436 kthread+0x2e8/0x3a0 kernel/kthread.c:376 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:308 Allocated by task 2569: kasan_save_stack+0x22/0x40 mm/kasan/common.c:45 kasan_set_track+0x25/0x30 mm/kasan/common.c:52 __kasan_slab_alloc+0x82/0x90 mm/kasan/common.c:325 kasan_slab_alloc include/linux/kasan.h:201 [inline] slab_post_alloc_hook mm/slab.h:761 [inline] slab_alloc_node mm/slub.c:3452 [inline] slab_alloc mm/slub.c:3460 [inline] __kmem_cache_alloc_lru mm/slub.c:3467 [inline] kmem_cache_alloc+0x1e4/0x430 mm/slub.c:3476 kmem_cache_zalloc include/linux/slab.h:710 [inline] __kernfs_new_node+0xd4/0x8b0 fs/kernfs/dir.c:614 kernfs_new_node fs/kernfs/dir.c:676 [inline] kernfs_create_dir_ns+0xa0/0x230 fs/kernfs/dir.c:1032 sysfs_create_dir_ns+0x12b/0x290 fs/sysfs/dir.c:59 create_dir lib/kobject.c:63 [inline] kobject_add_internal+0x2c9/0x8f0 lib/kobject.c:223 kobject_add_varg lib/kobject.c:358 [inline] kobject_add+0x154/0x1c0 lib/kobject.c:410 class_dir_create_and_add drivers/base/core.c:3016 [inline] get_device_parent+0x3d7/0x590 drivers/base/core.c:3071 device_add+0x2ae/0x1e90 drivers/base/core.c:3400 fw_load_sysfs_fallback drivers/base/firmware_loader/fallback.c:82 [inline] fw_load_from_user_helper drivers/base/firmware_loader/fallback.c:158 [inline] firmware_fallback_sysfs+0x2d9/0xba0 drivers/base/firmware_loader/fallback.c:234 _request_firmware+0xbcf/0x1190 drivers/base/firmware_loader/main.c:856 request_firmware_work_func+0xe1/0x240 drivers/base/firmware_loader/main.c:1105 process_one_work+0x9bf/0x1710 kernel/workqueue.c:2289 worker_thread+0x669/0x1090 kernel/workqueue.c:2436 kthread+0x2e8/0x3a0 kernel/kthread.c:376 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:308 Freed by task 5176: kasan_save_stack+0x22/0x40 mm/kasan/common.c:45 kasan_set_track+0x25/0x30 mm/kasan/common.c:52 kasan_save_free_info+0x2e/0x40 mm/kasan/generic.c:518 ____kasan_slab_free mm/kasan/common.c:236 [inline] ____kasan_slab_free+0x160/0x1c0 mm/kasan/common.c:200 kasan_slab_free include/linux/kasan.h:177 [inline] slab_free_hook mm/slub.c:1781 [inline] slab_free_freelist_hook+0x8b/0x1c0 mm/slub.c:1807 slab_free mm/slub.c:3787 [inline] kmem_cache_free+0xee/0x5c0 mm/slub.c:3809 kernfs_put.part.0+0x228/0x470 fs/kernfs/dir.c:568 kernfs_put+0x46/0x50 fs/kernfs/dir.c:542 __kernfs_remove+0x463/0x600 fs/kernfs/dir.c:1476 kernfs_remove+0x7b/0xa0 fs/kernfs/dir.c:1496 sysfs_remove_dir+0xc5/0x100 fs/sysfs/dir.c:101 __kobject_del+0xe2/0x1f0 lib/kobject.c:588 kobject_del lib/kobject.c:611 [inline] kobject_del+0x40/0x60 lib/kobject.c:603 device_del+0x820/0xc80 drivers/base/core.c:3677 usb_disconnect.cold+0x49b/0x6ed drivers/usb/core/hub.c:2264 hub_port_connect drivers/usb/core/hub.c:5247 [inline] hub_port_connect_change drivers/usb/core/hub.c:5552 [inline] port_event drivers/usb/core/hub.c:5712 [inline] hub_event+0x1fb5/0x4810 drivers/usb/core/hub.c:5794 process_one_work+0x9bf/0x1710 kernel/workqueue.c:2289 process_scheduled_works kernel/workqueue.c:2352 [inline] worker_thread+0x858/0x1090 kernel/workqueue.c:2438 kthread+0x2e8/0x3a0 kernel/kthread.c:376 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:308 The buggy address belongs to the object at ffff888038c83e80 which belongs to the cache kernfs_node_cache of size 168 The buggy address is located 48 bytes inside of 168-byte region [ffff888038c83e80, ffff888038c83f28) The buggy address belongs to the physical page: page:ffffea0000e320c0 refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x38c83 flags: 0xfff00000000200(slab|node=0|zone=1|lastcpupid=0x7ff) raw: 00fff00000000200 ffff8880125edc80 ffffea0000761e80 dead000000000002 raw: 0000000000000000 0000000080110011 00000001ffffffff 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 0x112cc0(GFP_USER|__GFP_NOWARN|__GFP_NORETRY), pid 31532, tgid 31532 (kworker/0:4), ts 1658070449727, free_ts 1657190019284 prep_new_page mm/page_alloc.c:2531 [inline] get_page_from_freelist+0x119c/0x2ce0 mm/page_alloc.c:4283 __alloc_pages+0x1cb/0x5b0 mm/page_alloc.c:5549 alloc_pages+0x1aa/0x270 mm/mempolicy.c:2287 alloc_slab_page mm/slub.c:1851 [inline] allocate_slab+0x25f/0x350 mm/slub.c:1998 new_slab mm/slub.c:2051 [inline] ___slab_alloc+0xa91/0x1400 mm/slub.c:3193 __slab_alloc.constprop.0+0x56/0xa0 mm/slub.c:3292 __slab_alloc_node mm/slub.c:3345 [inline] slab_alloc_node mm/slub.c:3442 [inline] slab_alloc mm/slub.c:3460 [inline] __kmem_cache_alloc_lru mm/slub.c:3467 [inline] kmem_cache_alloc+0x379/0x430 mm/slub.c:3476 kmem_cache_zalloc include/linux/slab.h:710 [inline] __kernfs_new_node+0xd4/0x8b0 fs/kernfs/dir.c:614 kernfs_new_node+0x97/0x120 fs/kernfs/dir.c:676 __kernfs_create_file+0x55/0x350 fs/kernfs/file.c:1047 sysfs_add_file_mode_ns+0x213/0x3f0 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+0x29/0x50 fs/sysfs/group.c:214 device_add_groups drivers/base/core.c:2573 [inline] device_add_attrs drivers/base/core.c:2693 [inline] device_add+0x842/0x1e90 drivers/base/core.c:3430 usb_new_device.cold+0x685/0x10ad drivers/usb/core/hub.c:2576 page last free stack trace: reset_page_owner include/linux/page_owner.h:24 [inline] free_pages_prepare mm/page_alloc.c:1446 [inline] free_pcp_prepare+0x65c/0xc00 mm/page_alloc.c:1496 free_unref_page_prepare mm/page_alloc.c:3369 [inline] free_unref_page+0x1d/0x490 mm/page_alloc.c:3464 __vunmap+0x85d/0xd30 mm/vmalloc.c:2727 free_work+0x5c/0x80 mm/vmalloc.c:100 process_one_work+0x9bf/0x1710 kernel/workqueue.c:2289 worker_thread+0x669/0x1090 kernel/workqueue.c:2436 kthread+0x2e8/0x3a0 kernel/kthread.c:376 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:308 Memory state around the buggy address: ffff888038c83d80: fc fc fc fa fb fb fb fb fb fb fb fb fb fb fb fb ffff888038c83e00: fb fb fb fb fb fb fb fb fc fc fc fc fc fc fc fc >ffff888038c83e80: fa fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ^ ffff888038c83f00: fb fb fb fb fb fc fc fc fc fc fc fc fc fc fc fc ffff888038c83f80: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ==================================================================