================================================================== BUG: KASAN: use-after-free in __lock_acquire+0x3d86/0x54a0 kernel/locking/lockdep.c:4885 Read of size 8 at addr ffff8881498f4da8 by task kworker/1:6/7052 CPU: 1 PID: 7052 Comm: kworker/1:6 Not tainted 5.14.0-rc3-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Workqueue: usb_hub_wq hub_event Call Trace: __dump_stack lib/dump_stack.c:88 [inline] dump_stack_lvl+0xcd/0x134 lib/dump_stack.c:105 print_address_description.constprop.0.cold+0x6c/0x309 mm/kasan/report.c:233 __kasan_report mm/kasan/report.c:419 [inline] kasan_report.cold+0x83/0xdf mm/kasan/report.c:436 __lock_acquire+0x3d86/0x54a0 kernel/locking/lockdep.c:4885 lock_acquire kernel/locking/lockdep.c:5625 [inline] lock_acquire+0x19d/0x4d0 kernel/locking/lockdep.c:5590 __raw_spin_lock_irq include/linux/spinlock_api_smp.h:128 [inline] _raw_spin_lock_irq+0x2f/0x40 kernel/locking/spinlock.c:167 do_wait_for_common kernel/sched/completion.c:86 [inline] __wait_for_common kernel/sched/completion.c:106 [inline] wait_for_common kernel/sched/completion.c:117 [inline] wait_for_completion+0x181/0x280 kernel/sched/completion.c:138 r871xu_dev_remove+0x80/0x320 drivers/staging/rtl8712/usb_intf.c:599 usb_unbind_interface+0x1d8/0x8d0 drivers/usb/core/driver.c:458 __device_release_driver+0x3bd/0x6f0 drivers/base/dd.c:1201 device_release_driver_internal drivers/base/dd.c:1232 [inline] device_release_driver+0x26/0x40 drivers/base/dd.c:1255 bus_remove_device+0x2eb/0x5a0 drivers/base/bus.c:529 device_del+0x502/0xd40 drivers/base/core.c:3542 usb_disable_device+0x35b/0x7b0 drivers/usb/core/message.c:1419 usb_disconnect.cold+0x27a/0x78e drivers/usb/core/hub.c:2225 hub_port_connect drivers/usb/core/hub.c:5199 [inline] hub_port_connect_change drivers/usb/core/hub.c:5488 [inline] port_event drivers/usb/core/hub.c:5634 [inline] hub_event+0x1c9c/0x4330 drivers/usb/core/hub.c:5716 process_one_work+0x98d/0x15b0 kernel/workqueue.c:2276 worker_thread+0x658/0x11f0 kernel/workqueue.c:2422 kthread+0x3c0/0x4a0 kernel/kthread.c:319 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:295 Allocated by task 2657: kasan_save_stack+0x1b/0x40 mm/kasan/common.c:38 kasan_set_track mm/kasan/common.c:46 [inline] set_alloc_info mm/kasan/common.c:434 [inline] ____kasan_kmalloc mm/kasan/common.c:513 [inline] __kasan_kmalloc+0x7c/0x90 mm/kasan/common.c:522 kmalloc include/linux/slab.h:596 [inline] tomoyo_realpath_from_path+0xc3/0x620 security/tomoyo/realpath.c:254 tomoyo_get_realpath security/tomoyo/file.c:151 [inline] tomoyo_path_perm+0x21b/0x400 security/tomoyo/file.c:822 security_inode_getattr+0xcf/0x140 security/security.c:1332 vfs_getattr fs/stat.c:139 [inline] vfs_statx+0x164/0x390 fs/stat.c:207 vfs_fstatat fs/stat.c:225 [inline] vfs_lstat include/linux/fs.h:3386 [inline] __do_sys_newlstat+0x91/0x110 fs/stat.c:380 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x35/0xb0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x44/0xae Freed by task 2657: kasan_save_stack+0x1b/0x40 mm/kasan/common.c:38 kasan_set_track+0x1c/0x30 mm/kasan/common.c:46 kasan_set_free_info+0x20/0x30 mm/kasan/generic.c:360 ____kasan_slab_free mm/kasan/common.c:366 [inline] ____kasan_slab_free mm/kasan/common.c:328 [inline] __kasan_slab_free+0xe0/0x110 mm/kasan/common.c:374 kasan_slab_free include/linux/kasan.h:230 [inline] slab_free_hook mm/slub.c:1625 [inline] slab_free_freelist_hook+0xb4/0x1b0 mm/slub.c:1650 slab_free mm/slub.c:3210 [inline] kfree+0xdb/0x3b0 mm/slub.c:4262 tomoyo_realpath_from_path+0x191/0x620 security/tomoyo/realpath.c:291 tomoyo_get_realpath security/tomoyo/file.c:151 [inline] tomoyo_path_perm+0x21b/0x400 security/tomoyo/file.c:822 security_inode_getattr+0xcf/0x140 security/security.c:1332 vfs_getattr fs/stat.c:139 [inline] vfs_statx+0x164/0x390 fs/stat.c:207 vfs_fstatat fs/stat.c:225 [inline] vfs_lstat include/linux/fs.h:3386 [inline] __do_sys_newlstat+0x91/0x110 fs/stat.c:380 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x35/0xb0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x44/0xae The buggy address belongs to the object at ffff8881498f4000 which belongs to the cache kmalloc-4k of size 4096 The buggy address is located 3496 bytes inside of 4096-byte region [ffff8881498f4000, ffff8881498f5000) The buggy address belongs to the page: page:ffffea0005263c00 refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x1498f0 head:ffffea0005263c00 order:3 compound_mapcount:0 compound_pincount:0 flags: 0x200000000010200(slab|head|node=0|zone=2) raw: 0200000000010200 0000000000000000 dead000000000122 ffff888100042140 raw: 0000000000000000 0000000000040004 00000001ffffffff 0000000000000000 page dumped because: kasan: bad access detected page_owner tracks the page as allocated page last allocated via order 3, migratetype Unmovable, gfp_mask 0xd2040(__GFP_IO|__GFP_NOWARN|__GFP_NORETRY|__GFP_COMP|__GFP_NOMEMALLOC), pid 2657, ts 155916608541, free_ts 155904714748 prep_new_page mm/page_alloc.c:2436 [inline] get_page_from_freelist+0x11d2/0x28b0 mm/page_alloc.c:4169 __alloc_pages+0x1b2/0x4e0 mm/page_alloc.c:5391 alloc_pages+0x18c/0x2a0 mm/mempolicy.c:2244 alloc_slab_page mm/slub.c:1688 [inline] allocate_slab+0x32e/0x4b0 mm/slub.c:1828 new_slab mm/slub.c:1891 [inline] new_slab_objects mm/slub.c:2637 [inline] ___slab_alloc+0x4ba/0x820 mm/slub.c:2800 __slab_alloc+0x68/0x80 mm/slub.c:2840 slab_alloc_node mm/slub.c:2922 [inline] slab_alloc mm/slub.c:2964 [inline] __kmalloc+0x2f1/0x310 mm/slub.c:4100 kmalloc include/linux/slab.h:596 [inline] tomoyo_realpath_from_path+0xc3/0x620 security/tomoyo/realpath.c:254 tomoyo_get_realpath security/tomoyo/file.c:151 [inline] tomoyo_check_open_permission+0x272/0x380 security/tomoyo/file.c:771 tomoyo_file_open security/tomoyo/tomoyo.c:311 [inline] tomoyo_file_open+0xa3/0xd0 security/tomoyo/tomoyo.c:306 security_file_open+0x52/0x4f0 security/security.c:1633 do_dentry_open+0x34e/0x1110 fs/open.c:813 do_open fs/namei.c:3374 [inline] path_openat+0x1c23/0x27f0 fs/namei.c:3507 do_filp_open+0x1aa/0x400 fs/namei.c:3534 do_sys_openat2+0x16d/0x420 fs/open.c:1204 do_sys_open fs/open.c:1220 [inline] __do_sys_open fs/open.c:1228 [inline] __se_sys_open fs/open.c:1224 [inline] __x64_sys_open+0x119/0x1c0 fs/open.c:1224 page last free stack trace: reset_page_owner include/linux/page_owner.h:24 [inline] free_pages_prepare mm/page_alloc.c:1346 [inline] free_pcp_prepare+0x2b3/0x670 mm/page_alloc.c:1397 free_unref_page_prepare mm/page_alloc.c:3332 [inline] free_unref_page+0x19/0x490 mm/page_alloc.c:3411 kvfree+0x42/0x50 mm/util.c:616 netdev_freemem net/core/dev.c:10798 [inline] free_netdev+0x494/0x5b0 net/core/dev.c:10976 rtl871x_load_fw_cb drivers/staging/rtl8712/hal_init.c:46 [inline] rtl871x_load_fw_cb.cold+0xf7/0x117 drivers/staging/rtl8712/hal_init.c:32 request_firmware_work_func+0x12c/0x230 drivers/base/firmware_loader/main.c:1081 process_one_work+0x98d/0x15b0 kernel/workqueue.c:2276 worker_thread+0x658/0x11f0 kernel/workqueue.c:2422 kthread+0x3c0/0x4a0 kernel/kthread.c:319 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:295 Memory state around the buggy address: ffff8881498f4c80: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff8881498f4d00: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb >ffff8881498f4d80: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ^ ffff8881498f4e00: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff8881498f4e80: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ==================================================================