================================================================== BUG: KASAN: use-after-free in hci_cmd_timeout+0x239/0x250 net/bluetooth/hci_core.c:1494 Read of size 8 at addr ffff888063854998 by task kworker/u5:5/3664 CPU: 0 PID: 3664 Comm: kworker/u5:5 Not tainted 6.0.0-rc6-next-20220923-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/22/2022 Workqueue: hci6 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 mm/kasan/report.c:284 [inline] print_report+0x15e/0x45d mm/kasan/report.c:395 kasan_report+0xbb/0x1f0 mm/kasan/report.c:495 hci_cmd_timeout+0x239/0x250 net/bluetooth/hci_core.c:1494 process_one_work+0x9bf/0x1710 kernel/workqueue.c:2289 worker_thread+0x665/0x1080 kernel/workqueue.c:2436 kthread+0x2e4/0x3a0 kernel/kthread.c:376 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:306 Allocated by task 3664: kasan_save_stack+0x1e/0x40 mm/kasan/common.c:45 kasan_set_track+0x21/0x30 mm/kasan/common.c:52 __kasan_slab_alloc+0x7e/0x80 mm/kasan/common.c:325 kasan_slab_alloc include/linux/kasan.h:201 [inline] slab_post_alloc_hook mm/slab.h:754 [inline] slab_alloc_node mm/slub.c:3336 [inline] slab_alloc mm/slub.c:3344 [inline] __kmem_cache_alloc_lru mm/slub.c:3351 [inline] kmem_cache_alloc+0x2b7/0x3d0 mm/slub.c:3360 skb_clone+0x16e/0x3c0 net/core/skbuff.c:1548 hci_cmd_work+0x191/0x570 net/bluetooth/hci_core.c:4064 process_one_work+0x9bf/0x1710 kernel/workqueue.c:2289 worker_thread+0x665/0x1080 kernel/workqueue.c:2436 kthread+0x2e4/0x3a0 kernel/kthread.c:376 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:306 Freed by task 3662: kasan_save_stack+0x1e/0x40 mm/kasan/common.c:45 kasan_set_track+0x21/0x30 mm/kasan/common.c:52 kasan_save_free_info+0x2a/0x40 mm/kasan/generic.c:511 ____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:1669 [inline] slab_free_freelist_hook+0x8b/0x1c0 mm/slub.c:1695 slab_free mm/slub.c:3599 [inline] kmem_cache_free+0xea/0x5b0 mm/slub.c:3621 kfree_skbmem+0xef/0x1b0 net/core/skbuff.c:714 __kfree_skb net/core/skbuff.c:771 [inline] kfree_skb_reason+0x193/0x4b0 net/core/skbuff.c:793 kfree_skb include/linux/skbuff.h:1207 [inline] hci_dev_open_sync+0xbe2/0x2190 net/bluetooth/hci_sync.c:4698 hci_dev_do_open+0x2d/0x70 net/bluetooth/hci_core.c:483 hci_power_on+0xda/0x620 net/bluetooth/hci_core.c:984 process_one_work+0x9bf/0x1710 kernel/workqueue.c:2289 worker_thread+0x665/0x1080 kernel/workqueue.c:2436 kthread+0x2e4/0x3a0 kernel/kthread.c:376 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:306 The buggy address belongs to the object at ffff8880638548c0 which belongs to the cache skbuff_head_cache of size 240 The buggy address is located 216 bytes inside of 240-byte region [ffff8880638548c0, ffff8880638549b0) The buggy address belongs to the physical page: page:ffffea00018e1500 refcount:1 mapcount:0 mapping:0000000000000000 index:0xffffea0000742480 pfn:0x63854 flags: 0xfff00000000200(slab|node=0|zone=1|lastcpupid=0x7ff) raw: 00fff00000000200 ffff8880126c0500 dead0000000c000c 0000000000000000 raw: ffffea0000742480 dead000000000005 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 0x12820(GFP_ATOMIC|__GFP_NOWARN|__GFP_NORETRY), pid 22, tgid 22 (ksoftirqd/1), ts 73843462153, free_ts 12309476464 prep_new_page mm/page_alloc.c:2538 [inline] get_page_from_freelist+0x1092/0x2d20 mm/page_alloc.c:4287 __alloc_pages+0x1c7/0x5a0 mm/page_alloc.c:5546 alloc_pages+0x1a6/0x270 mm/mempolicy.c:2280 alloc_slab_page mm/slub.c:1739 [inline] allocate_slab+0x213/0x300 mm/slub.c:1884 new_slab mm/slub.c:1937 [inline] ___slab_alloc+0xac1/0x1430 mm/slub.c:3119 kmem_cache_alloc_bulk+0x291/0x860 mm/slub.c:3768 napi_skb_cache_get+0xeb/0x170 net/core/skbuff.c:183 __alloc_skb+0x96/0x2f0 net/core/skbuff.c:420 __napi_alloc_skb+0x93/0x340 net/core/skbuff.c:575 napi_alloc_skb include/linux/skbuff.h:3208 [inline] page_to_skb+0x17d/0xc80 drivers/net/virtio_net.c:496 receive_mergeable drivers/net/virtio_net.c:1119 [inline] receive_buf+0xe0a/0x5560 drivers/net/virtio_net.c:1258 virtnet_receive drivers/net/virtio_net.c:1553 [inline] virtnet_poll+0x708/0x1310 drivers/net/virtio_net.c:1671 __napi_poll+0xb8/0x770 net/core/dev.c:6511 napi_poll net/core/dev.c:6578 [inline] net_rx_action+0x9fc/0xde0 net/core/dev.c:6689 __do_softirq+0x1f7/0xad8 kernel/softirq.c:571 page last free stack trace: reset_page_owner include/linux/page_owner.h:24 [inline] free_pages_prepare mm/page_alloc.c:1458 [inline] free_pcp_prepare+0x65c/0xd90 mm/page_alloc.c:1508 free_unref_page_prepare mm/page_alloc.c:3386 [inline] free_unref_page+0x19/0x4d0 mm/page_alloc.c:3482 free_contig_range+0xb1/0x180 mm/page_alloc.c:9468 destroy_args+0xa8/0x64c mm/debug_vm_pgtable.c:1031 debug_vm_pgtable+0x2954/0x29e5 mm/debug_vm_pgtable.c:1354 do_one_initcall+0x13d/0x780 init/main.c:1307 do_initcall_level init/main.c:1382 [inline] do_initcalls init/main.c:1398 [inline] do_basic_setup init/main.c:1417 [inline] kernel_init_freeable+0x6ff/0x788 init/main.c:1637 kernel_init+0x1a/0x1d0 init/main.c:1525 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:306 Memory state around the buggy address: ffff888063854880: fc fc fc fc fc fc fc fc fa fb fb fb fb fb fb fb ffff888063854900: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb >ffff888063854980: fb fb fb fb fb fb fc fc fc fc fc fc fc fc fc fc ^ ffff888063854a00: fa fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff888063854a80: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fc fc ==================================================================