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BUG: KASAN: use-after-free in atomic_read include/asm-generic/atomic-instrumented.h:26 [inline]
BUG: KASAN: use-after-free in refcount_inc_not_zero_checked+0x81/0x200 lib/refcount.c:123
Read of size 4 at addr ffff888096d71340 by task kworker/0:3/8930
CPU: 0 PID: 8930 Comm: kworker/0:3 Not tainted 5.2.0+ #97
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Workqueue: rcu_gp process_srcu
Call Trace:
__dump_stack lib/dump_stack.c:77 [inline]
dump_stack+0x172/0x1f0 lib/dump_stack.c:113
print_address_description.cold+0xd4/0x306 mm/kasan/report.c:351
__kasan_report.cold+0x1b/0x36 mm/kasan/report.c:482
kasan_report+0x12/0x17 mm/kasan/common.c:612
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_inc_not_zero_checked+0x81/0x200 lib/refcount.c:123
refcount_inc_checked+0x17/0x70 lib/refcount.c:156
sock_hold include/net/sock.h:649 [inline]
sk_add_node include/net/sock.h:701 [inline]
nr_insert_socket+0x2d/0xe0 net/netrom/af_netrom.c:137
nr_rx_frame+0x1605/0x1e73 net/netrom/af_netrom.c:1023
nr_loopback_timer+0x7b/0x170 net/netrom/nr_loopback.c:59
call_timer_fn+0x1ac/0x780 kernel/time/timer.c:1322
expire_timers kernel/time/timer.c:1366 [inline]
__run_timers kernel/time/timer.c:1685 [inline]
__run_timers kernel/time/timer.c:1653 [inline]
run_timer_softirq+0x697/0x17a0 kernel/time/timer.c:1698
__do_softirq+0x262/0x98c kernel/softirq.c:292
invoke_softirq kernel/softirq.c:373 [inline]
irq_exit+0x19b/0x1e0 kernel/softirq.c:413
exiting_irq arch/x86/include/asm/apic.h:537 [inline]
smp_apic_timer_interrupt+0x1a3/0x610 arch/x86/kernel/apic/apic.c:1095
apic_timer_interrupt+0xf/0x20 arch/x86/entry/entry_64.S:828
RIP: 0010:delay_tsc+0x33/0xc0 arch/x86/lib/delay.c:68
Code: bf 01 00 00 00 41 55 41 54 53 e8 08 17 18 fa e8 53 3a 07 fc 41 89 c5 0f 01 f9 66 90 48 c1 e2 20 48 09 c2 49 89 d4 eb 16 f3 90 01 00 00 00 e8 e3 16 18 fa e8 2e 3a 07 fc 44 39 e8 75 36 0f 01
RSP: 0018:ffff88806dd8fbb0 EFLAGS: 00000286 ORIG_RAX: ffffffffffffff13
RAX: 0000000080000000 RBX: 0000021597856060 RCX: 0000000000000000
RDX: 0000000000000001 RSI: ffffffff833de7bc RDI: 0000000000000001
RBP: ffff88806dd8fbd0 R08: ffff88806dd841c0 R09: 0000000000000040
R10: 0000000000000040 R11: ffffffff8a8c89a7 R12: 00000215978549b3
R13: 0000000000000000 R14: 0000000000002ced R15: 000000000002c047
__delay arch/x86/lib/delay.c:161 [inline]
__const_udelay+0x59/0x80 arch/x86/lib/delay.c:175
try_check_zero+0x201/0x330 kernel/rcu/srcutree.c:705
srcu_advance_state kernel/rcu/srcutree.c:1142 [inline]
process_srcu+0x329/0xe20 kernel/rcu/srcutree.c:1237
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
Allocated by task 8930:
save_stack+0x23/0x90 mm/kasan/common.c:69
set_track mm/kasan/common.c:77 [inline]
__kasan_kmalloc mm/kasan/common.c:487 [inline]
__kasan_kmalloc.constprop.0+0xcf/0xe0 mm/kasan/common.c:460
kasan_kmalloc+0x9/0x10 mm/kasan/common.c:501
__do_kmalloc mm/slab.c:3655 [inline]
__kmalloc+0x163/0x770 mm/slab.c:3664
kmalloc include/linux/slab.h:557 [inline]
sk_prot_alloc+0x23a/0x310 net/core/sock.c:1603
sk_alloc+0x39/0xf70 net/core/sock.c:1657
nr_make_new net/netrom/af_netrom.c:476 [inline]
nr_rx_frame+0x733/0x1e73 net/netrom/af_netrom.c:959
nr_loopback_timer+0x7b/0x170 net/netrom/nr_loopback.c:59
call_timer_fn+0x1ac/0x780 kernel/time/timer.c:1322
expire_timers kernel/time/timer.c:1366 [inline]
__run_timers kernel/time/timer.c:1685 [inline]
__run_timers kernel/time/timer.c:1653 [inline]
run_timer_softirq+0x697/0x17a0 kernel/time/timer.c:1698
__do_softirq+0x262/0x98c kernel/softirq.c:292
Freed by task 20918:
save_stack+0x23/0x90 mm/kasan/common.c:69
set_track mm/kasan/common.c:77 [inline]
__kasan_slab_free+0x102/0x150 mm/kasan/common.c:449
kasan_slab_free+0xe/0x10 mm/kasan/common.c:457
__cache_free mm/slab.c:3425 [inline]
kfree+0x10a/0x2c0 mm/slab.c:3756
sk_prot_free net/core/sock.c:1640 [inline]
__sk_destruct+0x4f7/0x6e0 net/core/sock.c:1726
sk_destruct+0x86/0xa0 net/core/sock.c:1734
__sk_free+0xfb/0x360 net/core/sock.c:1745
sk_free+0x42/0x50 net/core/sock.c:1756
sock_put include/net/sock.h:1725 [inline]
sock_efree+0x61/0x80 net/core/sock.c:2042
skb_release_head_state+0xeb/0x250 net/core/skbuff.c:652
skb_release_all+0x16/0x60 net/core/skbuff.c:663
__kfree_skb net/core/skbuff.c:679 [inline]
kfree_skb net/core/skbuff.c:697 [inline]
kfree_skb+0x101/0x3c0 net/core/skbuff.c:691
nr_accept+0x56e/0x700 net/netrom/af_netrom.c:819
__sys_accept4+0x34e/0x6a0 net/socket.c:1754
__do_sys_accept4 net/socket.c:1789 [inline]
__se_sys_accept4 net/socket.c:1786 [inline]
__x64_sys_accept4+0x97/0xf0 net/socket.c:1786
do_syscall_64+0xfd/0x6a0 arch/x86/entry/common.c:296
entry_SYSCALL_64_after_hwframe+0x49/0xbe
The buggy address belongs to the object at ffff888096d712c0
which belongs to the cache kmalloc-2k of size 2048
The buggy address is located 128 bytes inside of
2048-byte region [ffff888096d712c0, ffff888096d71ac0)
The buggy address belongs to the page:
page:ffffea00025b5c00 refcount:1 mapcount:0 mapping:ffff8880aa400e00 index:0x0 compound_mapcount: 0
flags: 0x1fffc0000010200(slab|head)
raw: 01fffc0000010200 ffffea0001a8ca88 ffffea0001776c88 ffff8880aa400e00
raw: 0000000000000000 ffff888096d701c0 0000000100000003 0000000000000000
page dumped because: kasan: bad access detected
Memory state around the buggy address:
ffff888096d71200: fb fb fb fb fb fb fb fb fc fc fc fc fc fc fc fc
ffff888096d71280: fc fc fc fc fc fc fc fc fb fb fb fb fb fb fb fb
>ffff888096d71300: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
^
ffff888096d71380: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
ffff888096d71400: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
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