================================================================== BUG: KASAN: use-after-free in __skb_unlink include/linux/skbuff.h:2051 [inline] BUG: KASAN: use-after-free in __skb_dequeue include/linux/skbuff.h:2070 [inline] BUG: KASAN: use-after-free in skb_dequeue+0xad/0x180 net/core/skbuff.c:3057 Read of size 8 at addr ffff8881e08bfc80 by task kworker/u5:6/408 CPU: 0 PID: 408 Comm: kworker/u5:6 Not tainted 5.4.125-syzkaller-00008-ga8f2bcabf9c5 #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Workqueue: hci4 hci_rx_work Call Trace: __dump_stack lib/dump_stack.c:77 [inline] dump_stack+0x1d8/0x24e lib/dump_stack.c:118 print_address_description+0x9b/0x650 mm/kasan/report.c:384 __kasan_report+0x182/0x260 mm/kasan/report.c:516 kasan_report+0x30/0x60 mm/kasan/common.c:653 __skb_unlink include/linux/skbuff.h:2051 [inline] __skb_dequeue include/linux/skbuff.h:2070 [inline] skb_dequeue+0xad/0x180 net/core/skbuff.c:3057 hci_rx_work+0x620/0x780 net/bluetooth/hci_core.c:4463 process_one_work+0x679/0x1030 kernel/workqueue.c:2277 worker_thread+0xa6f/0x1400 kernel/workqueue.c:2423 kthread+0x30f/0x330 kernel/kthread.c:268 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:352 Allocated by task 466: save_stack mm/kasan/common.c:70 [inline] set_track mm/kasan/common.c:78 [inline] __kasan_kmalloc+0x137/0x1e0 mm/kasan/common.c:529 slab_post_alloc_hook mm/slab.h:584 [inline] slab_alloc_node mm/slub.c:2821 [inline] slab_alloc mm/slub.c:2829 [inline] kmem_cache_alloc+0x115/0x290 mm/slub.c:2834 kmem_cache_alloc_node include/linux/slab.h:427 [inline] __alloc_skb+0x75/0x4d0 net/core/skbuff.c:198 alloc_skb include/linux/skbuff.h:1060 [inline] bt_skb_alloc include/net/bluetooth/bluetooth.h:339 [inline] h4_recv_buf+0x274/0xd00 drivers/bluetooth/hci_h4.c:182 h4_recv+0xf4/0x1b0 drivers/bluetooth/hci_h4.c:116 hci_uart_tty_receive+0x275/0x460 drivers/bluetooth/hci_ldisc.c:613 tiocsti drivers/tty/tty_io.c:2197 [inline] tty_ioctl+0xd48/0x1710 drivers/tty/tty_io.c:2573 do_vfs_ioctl+0x76a/0x1720 fs/ioctl.c:47 ksys_ioctl fs/ioctl.c:742 [inline] __do_sys_ioctl fs/ioctl.c:749 [inline] __se_sys_ioctl fs/ioctl.c:747 [inline] __x64_sys_ioctl+0xd4/0x110 fs/ioctl.c:747 do_syscall_64+0xcb/0x1e0 arch/x86/entry/common.c:290 entry_SYSCALL_64_after_hwframe+0x44/0xa9 Freed by task 408: save_stack mm/kasan/common.c:70 [inline] set_track mm/kasan/common.c:78 [inline] kasan_set_free_info mm/kasan/common.c:345 [inline] __kasan_slab_free+0x18a/0x240 mm/kasan/common.c:487 slab_free_hook mm/slub.c:1454 [inline] slab_free_freelist_hook+0x7b/0x150 mm/slub.c:1492 slab_free mm/slub.c:3072 [inline] kmem_cache_free+0xb8/0x5f0 mm/slub.c:3088 hci_event_packet+0xa284/0x22220 net/bluetooth/hci_event.c:6067 hci_rx_work+0x287/0x780 net/bluetooth/hci_core.c:4498 process_one_work+0x679/0x1030 kernel/workqueue.c:2277 worker_thread+0xa6f/0x1400 kernel/workqueue.c:2423 kthread+0x30f/0x330 kernel/kthread.c:268 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:352 The buggy address belongs to the object at ffff8881e08bfc80 which belongs to the cache skbuff_head_cache of size 240 The buggy address is located 0 bytes inside of 240-byte region [ffff8881e08bfc80, ffff8881e08bfd70) The buggy address belongs to the page: page:ffffea0007822fc0 refcount:1 mapcount:0 mapping:ffff8881f1dde280 index:0x0 flags: 0x8000000000000200(slab) raw: 8000000000000200 dead000000000100 dead000000000122 ffff8881f1dde280 raw: 0000000000000000 00000000000c000c 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 0x12a20(GFP_ATOMIC|__GFP_NOWARN|__GFP_NORETRY) set_page_owner include/linux/page_owner.h:31 [inline] post_alloc_hook mm/page_alloc.c:2165 [inline] prep_new_page+0x19a/0x380 mm/page_alloc.c:2171 get_page_from_freelist+0x550/0x8b0 mm/page_alloc.c:3794 __alloc_pages_nodemask+0x3a2/0x880 mm/page_alloc.c:4855 alloc_slab_page+0x39/0x3e0 mm/slub.c:342 allocate_slab mm/slub.c:1675 [inline] new_slab+0x97/0x460 mm/slub.c:1741 new_slab_objects mm/slub.c:2498 [inline] ___slab_alloc+0x330/0x4c0 mm/slub.c:2659 __slab_alloc mm/slub.c:2699 [inline] slab_alloc_node mm/slub.c:2784 [inline] slab_alloc mm/slub.c:2829 [inline] kmem_cache_alloc+0x18b/0x290 mm/slub.c:2834 kmem_cache_alloc_node include/linux/slab.h:427 [inline] __alloc_skb+0x75/0x4d0 net/core/skbuff.c:198 alloc_skb include/linux/skbuff.h:1060 [inline] bt_skb_alloc include/net/bluetooth/bluetooth.h:339 [inline] hci_prepare_cmd net/bluetooth/hci_request.c:296 [inline] hci_req_add_ev+0xa4/0x3c0 net/bluetooth/hci_request.c:330 bredr_init net/bluetooth/hci_core.c:200 [inline] hci_init1_req+0x134/0x270 net/bluetooth/hci_core.c:256 __hci_req_sync+0x174/0x8a0 net/bluetooth/hci_request.c:205 __hci_init net/bluetooth/hci_core.c:868 [inline] hci_dev_do_open+0xafe/0x1670 net/bluetooth/hci_core.c:1528 hci_power_on+0x155/0x580 net/bluetooth/hci_core.c:2200 process_one_work+0x679/0x1030 kernel/workqueue.c:2277 worker_thread+0xa6f/0x1400 kernel/workqueue.c:2423 kthread+0x30f/0x330 kernel/kthread.c:268 page last free stack trace: reset_page_owner include/linux/page_owner.h:24 [inline] free_pages_prepare mm/page_alloc.c:1176 [inline] free_pcp_prepare+0x1a9/0x270 mm/page_alloc.c:1233 free_unref_page_prepare mm/page_alloc.c:3085 [inline] free_unref_page mm/page_alloc.c:3134 [inline] free_the_page mm/page_alloc.c:4915 [inline] __free_pages+0x9c/0x250 mm/page_alloc.c:4923 selinux_genfs_get_sid security/selinux/hooks.c:1367 [inline] inode_doinit_with_dentry+0xb34/0x11d0 security/selinux/hooks.c:1562 security_d_instantiate+0xa5/0x100 security/security.c:1882 d_instantiate+0x51/0x90 fs/dcache.c:1954 debugfs_create_dir+0x1bc/0x3f0 fs/debugfs/inode.c:571 hci_register_dev+0x297/0x710 net/bluetooth/hci_core.c:3333 hci_uart_register_dev drivers/bluetooth/hci_ldisc.c:682 [inline] hci_uart_set_proto drivers/bluetooth/hci_ldisc.c:706 [inline] hci_uart_tty_ioctl+0x89e/0xa10 drivers/bluetooth/hci_ldisc.c:760 tty_ioctl+0xf68/0x1710 drivers/tty/tty_io.c:2666 do_vfs_ioctl+0x76a/0x1720 fs/ioctl.c:47 ksys_ioctl fs/ioctl.c:742 [inline] __do_sys_ioctl fs/ioctl.c:749 [inline] __se_sys_ioctl fs/ioctl.c:747 [inline] __x64_sys_ioctl+0xd4/0x110 fs/ioctl.c:747 do_syscall_64+0xcb/0x1e0 arch/x86/entry/common.c:290 entry_SYSCALL_64_after_hwframe+0x44/0xa9 Memory state around the buggy address: ffff8881e08bfb80: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff8881e08bfc00: fb fb fb fb fb fb fc fc fc fc fc fc fc fc fc fc >ffff8881e08bfc80: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ^ ffff8881e08bfd00: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fc fc ffff8881e08bfd80: fc fc fc fc fc fc fc fc fb fb fb fb fb fb fb fb ================================================================== kasan: CONFIG_KASAN_INLINE enabled kasan: GPF could be caused by NULL-ptr deref or user memory access general protection fault: 0000 [#1] PREEMPT SMP KASAN CPU: 0 PID: 408 Comm: kworker/u5:6 Tainted: G B 5.4.125-syzkaller-00008-ga8f2bcabf9c5 #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Workqueue: hci4 hci_rx_work RIP: 0010:__write_once_size include/linux/compiler.h:293 [inline] RIP: 0010:__skb_unlink include/linux/skbuff.h:2054 [inline] RIP: 0010:__skb_dequeue include/linux/skbuff.h:2070 [inline] RIP: 0010:skb_dequeue+0xe8/0x180 net/core/skbuff.c:3057 Code: 80 3c 38 00 74 05 e8 87 8f 1e fe 49 8b 5c 24 08 4d 8d 6e 08 ba 10 00 00 00 4c 89 e7 31 f6 e8 3f 62 1e fe 4c 89 e8 48 c1 e8 03 <42> 80 3c 38 00 74 08 4c 89 ef e8 d9 8f 1e fe 49 89 5e 08 48 89 d8 RSP: 0018:ffff8881e1adfc50 EFLAGS: 00010002 RAX: 0000000000000001 RBX: ffff8881e08bfc80 RCX: 0000000000000000 RDX: 0000000000000010 RSI: 0000000000000000 RDI: ffff8881e08bfc90 RBP: 1ffff1103bed0172 R08: dffffc0000000000 R09: ffff8881e08bfc80 R10: ffffed103c117f92 R11: 00000000000000fb R12: ffff8881e08bfc80 R13: 0000000000000008 R14: 0000000000000000 R15: dffffc0000000000 FS: 0000000000000000(0000) GS:ffff8881f6e00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00000000005198f0 CR3: 00000001e6370000 CR4: 00000000001406f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: hci_rx_work+0x620/0x780 net/bluetooth/hci_core.c:4463 process_one_work+0x679/0x1030 kernel/workqueue.c:2277 worker_thread+0xa6f/0x1400 kernel/workqueue.c:2423 kthread+0x30f/0x330 kernel/kthread.c:268 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:352 Modules linked in: ---[ end trace 29535e1e0975b2a5 ]--- RIP: 0010:__write_once_size include/linux/compiler.h:293 [inline] RIP: 0010:__skb_unlink include/linux/skbuff.h:2054 [inline] RIP: 0010:__skb_dequeue include/linux/skbuff.h:2070 [inline] RIP: 0010:skb_dequeue+0xe8/0x180 net/core/skbuff.c:3057 Code: 80 3c 38 00 74 05 e8 87 8f 1e fe 49 8b 5c 24 08 4d 8d 6e 08 ba 10 00 00 00 4c 89 e7 31 f6 e8 3f 62 1e fe 4c 89 e8 48 c1 e8 03 <42> 80 3c 38 00 74 08 4c 89 ef e8 d9 8f 1e fe 49 89 5e 08 48 89 d8 RSP: 0018:ffff8881e1adfc50 EFLAGS: 00010002 RAX: 0000000000000001 RBX: ffff8881e08bfc80 RCX: 0000000000000000 RDX: 0000000000000010 RSI: 0000000000000000 RDI: ffff8881e08bfc90 RBP: 1ffff1103bed0172 R08: dffffc0000000000 R09: ffff8881e08bfc80 R10: ffffed103c117f92 R11: 00000000000000fb R12: ffff8881e08bfc80 R13: 0000000000000008 R14: 0000000000000000 R15: dffffc0000000000 FS: 0000000000000000(0000) GS:ffff8881f6e00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00000000005198f0 CR3: 00000001e6370000 CR4: 00000000001406f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 ---------------- Code disassembly (best guess): 0: 80 3c 38 00 cmpb $0x0,(%rax,%rdi,1) 4: 74 05 je 0xb 6: e8 87 8f 1e fe callq 0xfe1e8f92 b: 49 8b 5c 24 08 mov 0x8(%r12),%rbx 10: 4d 8d 6e 08 lea 0x8(%r14),%r13 14: ba 10 00 00 00 mov $0x10,%edx 19: 4c 89 e7 mov %r12,%rdi 1c: 31 f6 xor %esi,%esi 1e: e8 3f 62 1e fe callq 0xfe1e6262 23: 4c 89 e8 mov %r13,%rax 26: 48 c1 e8 03 shr $0x3,%rax 2a: 42 80 3c 38 00 cmpb $0x0,(%rax,%r15,1) <-- trapping instruction 2f: 74 08 je 0x39 31: 4c 89 ef mov %r13,%rdi 34: e8 d9 8f 1e fe callq 0xfe1e9012 39: 49 89 5e 08 mov %rbx,0x8(%r14) 3d: 48 89 d8 mov %rbx,%rax