==================================================================
BUG: KASAN: use-after-free in atomic_read include/asm-generic/atomic-instrumented.h:26 [inline]
BUG: KASAN: use-after-free in refcount_read include/linux/refcount.h:43 [inline]
BUG: KASAN: use-after-free in skb_unref include/linux/skbuff.h:1010 [inline]
BUG: KASAN: use-after-free in kfree_skb+0x38/0x3c0 net/core/skbuff.c:693
Read of size 4 at addr ffff88809a906f14 by task syz-executor.4/8947
CPU: 0 PID: 8947 Comm: syz-executor.4 Not tainted 5.4.0-rc5+ #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Call Trace:
__dump_stack lib/dump_stack.c:77 [inline]
dump_stack+0x172/0x1f0 lib/dump_stack.c:113
print_address_description.constprop.0.cold+0xd4/0x30b mm/kasan/report.c:374
__kasan_report.cold+0x1b/0x41 mm/kasan/report.c:506
kasan_report+0x12/0x20 mm/kasan/common.c:634
check_memory_region_inline mm/kasan/generic.c:185 [inline]
check_memory_region+0x134/0x1a0 mm/kasan/generic.c:192
__kasan_check_read+0x11/0x20 mm/kasan/common.c:92
atomic_read include/asm-generic/atomic-instrumented.h:26 [inline]
refcount_read include/linux/refcount.h:43 [inline]
skb_unref include/linux/skbuff.h:1010 [inline]
kfree_skb+0x38/0x3c0 net/core/skbuff.c:693
bcsp_close+0xc7/0x130 drivers/bluetooth/hci_bcsp.c:748
hci_uart_tty_close+0x21e/0x280 drivers/bluetooth/hci_ldisc.c:548
tty_ldisc_close.isra.0+0x119/0x1a0 drivers/tty/tty_ldisc.c:494
tty_ldisc_kill+0x9c/0x160 drivers/tty/tty_ldisc.c:642
tty_ldisc_release+0xe9/0x2b0 drivers/tty/tty_ldisc.c:814
tty_release_struct+0x1b/0x50 drivers/tty/tty_io.c:1612
tty_release+0xbcb/0xe90 drivers/tty/tty_io.c:1785
__fput+0x2ff/0x890 fs/file_table.c:280
____fput+0x16/0x20 fs/file_table.c:313
task_work_run+0x145/0x1c0 kernel/task_work.c:113
tracehook_notify_resume include/linux/tracehook.h:188 [inline]
exit_to_usermode_loop+0x316/0x380 arch/x86/entry/common.c:163
prepare_exit_to_usermode arch/x86/entry/common.c:194 [inline]
syscall_return_slowpath arch/x86/entry/common.c:274 [inline]
do_syscall_64+0x65f/0x760 arch/x86/entry/common.c:300
entry_SYSCALL_64_after_hwframe+0x49/0xbe
RIP: 0033:0x413ad1
Code: 75 14 b8 03 00 00 00 0f 05 48 3d 01 f0 ff ff 0f 83 04 1b 00 00 c3 48 83 ec 08 e8 0a fc ff ff 48 89 04 24 b8 03 00 00 00 0f 05 <48> 8b 3c 24 48 89 c2 e8 53 fc ff ff 48 89 d0 48 83 c4 08 48 3d 01
RSP: 002b:0000000000a6fbf0 EFLAGS: 00000293 ORIG_RAX: 0000000000000003
RAX: 0000000000000000 RBX: 000000000000000a RCX: 0000000000413ad1
RDX: 0000000000000000 RSI: 0000000000001f51 RDI: 0000000000000009
RBP: 0000000000000001 R08: 00000000a4be7f51 R09: 00000000a4be7f55
R10: 0000000000a6fcd0 R11: 0000000000000293 R12: 000000000075c9a0
R13: 000000000075c9a0 R14: 0000000000761ce0 R15: 000000000075bfd4
Allocated by task 53:
save_stack+0x23/0x90 mm/kasan/common.c:69
set_track mm/kasan/common.c:77 [inline]
__kasan_kmalloc mm/kasan/common.c:510 [inline]
__kasan_kmalloc.constprop.0+0xcf/0xe0 mm/kasan/common.c:483
kasan_slab_alloc+0xf/0x20 mm/kasan/common.c:518
slab_post_alloc_hook mm/slab.h:584 [inline]
slab_alloc_node mm/slab.c:3262 [inline]
kmem_cache_alloc_node+0x138/0x740 mm/slab.c:3574
__alloc_skb+0xd5/0x5e0 net/core/skbuff.c:197
alloc_skb include/linux/skbuff.h:1049 [inline]
bt_skb_alloc include/net/bluetooth/bluetooth.h:339 [inline]
bcsp_recv+0x8c1/0x13a0 drivers/bluetooth/hci_bcsp.c:670
hci_uart_tty_receive+0x279/0x6e0 drivers/bluetooth/hci_ldisc.c:613
tty_ldisc_receive_buf+0x15f/0x1c0 drivers/tty/tty_buffer.c:465
tty_port_default_receive_buf+0x7d/0xb0 drivers/tty/tty_port.c:38
receive_buf drivers/tty/tty_buffer.c:481 [inline]
flush_to_ldisc+0x222/0x390 drivers/tty/tty_buffer.c:533
process_one_work+0x9af/0x1740 kernel/workqueue.c:2269
worker_thread+0x98/0xe40 kernel/workqueue.c:2415
kthread+0x361/0x430 kernel/kthread.c:255
ret_from_fork+0x24/0x30 arch/x86/entry/entry_64.S:352
Freed by task 53:
save_stack+0x23/0x90 mm/kasan/common.c:69
set_track mm/kasan/common.c:77 [inline]
kasan_set_free_info mm/kasan/common.c:332 [inline]
__kasan_slab_free+0x102/0x150 mm/kasan/common.c:471
kasan_slab_free+0xe/0x10 mm/kasan/common.c:480
__cache_free mm/slab.c:3425 [inline]
kmem_cache_free+0x86/0x320 mm/slab.c:3693
kfree_skbmem net/core/skbuff.c:623 [inline]
kfree_skbmem+0xc5/0x150 net/core/skbuff.c:617
__kfree_skb net/core/skbuff.c:680 [inline]
kfree_skb net/core/skbuff.c:697 [inline]
kfree_skb+0x109/0x3c0 net/core/skbuff.c:691
bcsp_recv+0x2d8/0x13a0 drivers/bluetooth/hci_bcsp.c:608
hci_uart_tty_receive+0x279/0x6e0 drivers/bluetooth/hci_ldisc.c:613
tty_ldisc_receive_buf+0x15f/0x1c0 drivers/tty/tty_buffer.c:465
tty_port_default_receive_buf+0x7d/0xb0 drivers/tty/tty_port.c:38
receive_buf drivers/tty/tty_buffer.c:481 [inline]
flush_to_ldisc+0x222/0x390 drivers/tty/tty_buffer.c:533
process_one_work+0x9af/0x1740 kernel/workqueue.c:2269
worker_thread+0x98/0xe40 kernel/workqueue.c:2415
kthread+0x361/0x430 kernel/kthread.c:255
ret_from_fork+0x24/0x30 arch/x86/entry/entry_64.S:352
The buggy address belongs to the object at ffff88809a906e40
which belongs to the cache skbuff_head_cache of size 224
The buggy address is located 212 bytes inside of
224-byte region [ffff88809a906e40, ffff88809a906f20)
The buggy address belongs to the page:
page:ffffea00026a4180 refcount:1 mapcount:0 mapping:ffff8880a99db8c0 index:0x0
flags: 0x1fffc0000000200(slab)
raw: 01fffc0000000200 ffffea000296d4c8 ffffea00025b8308 ffff8880a99db8c0
raw: 0000000000000000 ffff88809a906080 000000010000000c 0000000000000000
page dumped because: kasan: bad access detected
Memory state around the buggy address:
ffff88809a906e00: fc fc fc fc fc fc fc fc fb fb fb fb fb fb fb fb
ffff88809a906e80: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
>ffff88809a906f00: fb fb fb fb fc fc fc fc fc fc fc fc fc fc fc fc
^
ffff88809a906f80: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
ffff88809a907000: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
==================================================================