================================================================== BUG: KASAN: use-after-free in hci_cmd_timeout+0x24b/0x250 net/bluetooth/hci_core.c:1474 Read of size 2 at addr ffff88807b23e008 by task kworker/0:0/6 CPU: 0 PID: 6 Comm: kworker/0:0 Not tainted 5.18.0-syzkaller-13842-g952923ddc011 #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Workqueue: events hci_cmd_timeout 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/0x495 mm/kasan/report.c:313 print_report mm/kasan/report.c:429 [inline] kasan_report.cold+0xf4/0x1c6 mm/kasan/report.c:491 hci_cmd_timeout+0x24b/0x250 net/bluetooth/hci_core.c:1474 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:302 Allocated by task 2978: 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_kmalloc mm/kasan/common.c:515 [inline] ____kasan_kmalloc mm/kasan/common.c:474 [inline] __kasan_kmalloc+0xa9/0xd0 mm/kasan/common.c:524 kmalloc include/linux/slab.h:600 [inline] kzalloc include/linux/slab.h:733 [inline] kernfs_fop_open+0x317/0xda0 fs/kernfs/file.c:621 do_dentry_open+0x4a1/0x11f0 fs/open.c:848 do_open fs/namei.c:3520 [inline] path_openat+0x1c71/0x2910 fs/namei.c:3653 do_filp_open+0x1aa/0x400 fs/namei.c:3680 do_sys_openat2+0x16d/0x4c0 fs/open.c:1278 do_sys_open fs/open.c:1294 [inline] __do_sys_openat fs/open.c:1310 [inline] __se_sys_openat fs/open.c:1305 [inline] __x64_sys_openat+0x13f/0x1f0 fs/open.c:1305 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+0x46/0xb0 Freed by task 3655: 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+0x166/0x1a0 mm/kasan/common.c:328 kasan_slab_free include/linux/kasan.h:200 [inline] slab_free_hook mm/slub.c:1727 [inline] slab_free_freelist_hook+0x8b/0x1c0 mm/slub.c:1753 slab_free mm/slub.c:3507 [inline] kfree+0xd6/0x4d0 mm/slub.c:4555 skb_free_head+0xac/0x110 net/core/skbuff.c:655 skb_release_data+0x67a/0x810 net/core/skbuff.c:677 skb_release_all net/core/skbuff.c:742 [inline] __kfree_skb net/core/skbuff.c:756 [inline] kfree_skb_reason.part.0+0xe2/0x320 net/core/skbuff.c:778 kfree_skb_reason+0x85/0x110 include/linux/refcount.h:279 kfree_skb include/linux/skbuff.h:1375 [inline] hci_dev_open_sync+0xb8c/0x2160 net/bluetooth/hci_sync.c:4052 hci_dev_do_open+0x32/0x70 net/bluetooth/hci_core.c:482 hci_power_on+0x133/0x630 net/bluetooth/hci_core.c:963 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:302 The buggy address belongs to the object at ffff88807b23e000 which belongs to the cache kmalloc-512 of size 512 The buggy address is located 8 bytes inside of 512-byte region [ffff88807b23e000, ffff88807b23e200) The buggy address belongs to the physical page: page:ffffea0001ec8f00 refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x7b23c head:ffffea0001ec8f00 order:2 compound_mapcount:0 compound_pincount:0 flags: 0xfff00000010200(slab|head|node=0|zone=1|lastcpupid=0x7ff) raw: 00fff00000010200 ffffea0001fca200 dead000000000003 ffff888011841c80 raw: 0000000000000000 0000000000100010 00000001ffffffff 0000000000000000 page dumped because: kasan: bad access detected page_owner tracks the page as allocated page last allocated via order 2, migratetype Unmovable, gfp_mask 0xd20c0(__GFP_IO|__GFP_FS|__GFP_NOWARN|__GFP_NORETRY|__GFP_COMP|__GFP_NOMEMALLOC), pid 2979, tgid 2979 (udevadm), ts 14350472624, free_ts 12026527112 prep_new_page mm/page_alloc.c:2456 [inline] get_page_from_freelist+0x1290/0x3b70 mm/page_alloc.c:4198 __alloc_pages+0x1c7/0x510 mm/page_alloc.c:5426 alloc_pages+0x1aa/0x310 mm/mempolicy.c:2272 alloc_slab_page mm/slub.c:1797 [inline] allocate_slab+0x26c/0x3c0 mm/slub.c:1942 new_slab mm/slub.c:2002 [inline] ___slab_alloc+0x985/0xd90 mm/slub.c:3002 __slab_alloc.constprop.0+0x4d/0xa0 mm/slub.c:3089 slab_alloc_node mm/slub.c:3180 [inline] __kmalloc_node_track_caller+0x2cb/0x360 mm/slub.c:4950 kmalloc_reserve net/core/skbuff.c:354 [inline] __alloc_skb+0xde/0x340 net/core/skbuff.c:426 alloc_skb include/linux/skbuff.h:1426 [inline] alloc_uevent_skb+0x7b/0x210 lib/kobject_uevent.c:290 uevent_net_broadcast_untagged lib/kobject_uevent.c:326 [inline] kobject_uevent_net_broadcast lib/kobject_uevent.c:409 [inline] kobject_uevent_env+0xc42/0x1660 lib/kobject_uevent.c:593 kobject_synth_uevent+0x701/0x850 lib/kobject_uevent.c:208 uevent_store+0x42/0x90 drivers/base/bus.c:581 drv_attr_store+0x6d/0xa0 drivers/base/bus.c:77 sysfs_kf_write+0x110/0x160 fs/sysfs/file.c:136 kernfs_fop_write_iter+0x3f8/0x610 fs/kernfs/file.c:290 call_write_iter include/linux/fs.h:2058 [inline] new_sync_write+0x38a/0x560 fs/read_write.c:504 page last free stack trace: reset_page_owner include/linux/page_owner.h:24 [inline] free_pages_prepare mm/page_alloc.c:1371 [inline] free_pcp_prepare+0x549/0xd20 mm/page_alloc.c:1421 free_unref_page_prepare mm/page_alloc.c:3343 [inline] free_unref_page+0x19/0x6a0 mm/page_alloc.c:3438 free_contig_range+0xb1/0x180 mm/page_alloc.c:9314 destroy_args+0xa8/0x646 mm/debug_vm_pgtable.c:1031 debug_vm_pgtable+0x2a14/0x2aa5 mm/debug_vm_pgtable.c:1354 do_one_initcall+0x103/0x650 init/main.c:1295 do_initcall_level init/main.c:1368 [inline] do_initcalls init/main.c:1384 [inline] do_basic_setup init/main.c:1403 [inline] kernel_init_freeable+0x6b1/0x73a init/main.c:1610 kernel_init+0x1a/0x1d0 init/main.c:1499 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:302 Memory state around the buggy address: ffff88807b23df00: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ffff88807b23df80: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc >ffff88807b23e000: fa fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ^ ffff88807b23e080: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff88807b23e100: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ==================================================================