==================================================================
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+0x7c/0x280 lib/refcount.c:123
Read of size 4 at addr ffff88808b522680 by task syz-executor.5/6992
CPU: 0 PID: 6992 Comm: syz-executor.5 Not tainted 5.3.0-rc1+ #49
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+0x1d8/0x2f8 lib/dump_stack.c:113
print_address_description+0x75/0x5b0 mm/kasan/report.c:351
__kasan_report+0x14b/0x1c0 mm/kasan/report.c:482
kasan_report+0x26/0x50 mm/kasan/common.c:612
check_memory_region_inline mm/kasan/generic.c:182 [inline]
check_memory_region+0x2cf/0x2e0 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+0x7c/0x280 lib/refcount.c:123
refcount_inc_checked+0x15/0x50 lib/refcount.c:156
sock_hold include/net/sock.h:649 [inline]
sk_add_node include/net/sock.h:701 [inline]
nr_insert_socket net/netrom/af_netrom.c:137 [inline]
nr_rx_frame+0x17bc/0x1e40 net/netrom/af_netrom.c:1023
nr_loopback_timer+0x6a/0x140 net/netrom/nr_loopback.c:59
call_timer_fn+0xec/0x200 kernel/time/timer.c:1322
expire_timers kernel/time/timer.c:1366 [inline]
__run_timers+0x7cd/0x9c0 kernel/time/timer.c:1685
run_timer_softirq+0x4a/0x90 kernel/time/timer.c:1698
__do_softirq+0x333/0x7c4 arch/x86/include/asm/paravirt.h:778
invoke_softirq kernel/softirq.c:373 [inline]
irq_exit+0x227/0x230 kernel/softirq.c:413
exiting_irq arch/x86/include/asm/apic.h:537 [inline]
smp_apic_timer_interrupt+0x113/0x280 arch/x86/kernel/apic/apic.c:1095
apic_timer_interrupt+0xf/0x20 arch/x86/entry/entry_64.S:828
RIP: 0010:check_kcov_mode kernel/kcov.c:79 [inline]
RIP: 0010:write_comp_data kernel/kcov.c:123 [inline]
RIP: 0010:__sanitizer_cov_trace_const_cmp8+0x21/0x80 kernel/kcov.c:196
Code: 2e 0f 1f 84 00 00 00 00 00 4c 8b 04 24 65 48 8b 14 25 40 fd 01 00 65 8b 05 a8 1e 8a 7e a9 00 01 1f 00 75 61 8b 82 f0 12 00 00 <83> f8 03 75 56 48 8b 8a f8 12 00 00 44 8b 8a f4 12 00 00 49 c1 e1
RSP: 0018:ffff8880891072b0 EFLAGS: 00000246 ORIG_RAX: ffffffffffffff13
RAX: 0000000000000000 RBX: ffffea000199dec8 RCX: ffff88805aefc580
RDX: ffff88805aefc580 RSI: 0000000000000000 RDI: 0000000000000000
RBP: ffff8880891072f0 R08: ffffffff81a86ba6 R09: fffff94000333bd9
R10: fffff94000333bd9 R11: 0000000000000000 R12: 0000000000000000
R13: dead000000000100 R14: 1ffffd4000333bd9 R15: ffffea000199dec0
zap_pte_range mm/memory.c:1059 [inline]
zap_pmd_range mm/memory.c:1161 [inline]
zap_pud_range mm/memory.c:1190 [inline]
zap_p4d_range mm/memory.c:1211 [inline]
unmap_page_range+0x17e0/0x24e0 mm/memory.c:1232
unmap_single_vma+0x1d4/0x2e0 mm/memory.c:1277
unmap_vmas+0x245/0x380 mm/memory.c:1309
exit_mmap+0x2b7/0x5a0 mm/mmap.c:3145
__mmput+0x120/0x3a0 kernel/fork.c:1064
mmput+0x5d/0x70 kernel/fork.c:1085
exit_mm+0x585/0x640 kernel/exit.c:547
do_exit+0x5d0/0x2340 kernel/exit.c:865
do_group_exit+0x15c/0x2b0 kernel/exit.c:982
get_signal+0x51c/0x1dd0 kernel/signal.c:2728
do_signal+0x7b/0x720 arch/x86/kernel/signal.c:815
exit_to_usermode_loop arch/x86/entry/common.c:159 [inline]
prepare_exit_to_usermode+0x303/0x580 arch/x86/entry/common.c:194
syscall_return_slowpath+0x113/0x4a0 arch/x86/entry/common.c:274
do_syscall_64+0x126/0x140 arch/x86/entry/common.c:299
entry_SYSCALL_64_after_hwframe+0x49/0xbe
RIP: 0033:0x459829
Code: fd b7 fb ff c3 66 2e 0f 1f 84 00 00 00 00 00 66 90 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 0f 83 cb b7 fb ff c3 66 2e 0f 1f 84 00 00 00 00
RSP: 002b:00007fc8550edc78 EFLAGS: 00000246 ORIG_RAX: 0000000000000001
RAX: ffffffffffffffe0 RBX: 0000000000000003 RCX: 0000000000459829
RDX: 000000000000000a RSI: 0000000020000080 RDI: 0000000000000004
RBP: 000000000075bf20 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 00007fc8550ee6d4
R13: 00000000004c9657 R14: 00000000004e09f0 R15: 00000000ffffffff
Allocated by task 6992:
save_stack mm/kasan/common.c:69 [inline]
set_track mm/kasan/common.c:77 [inline]
__kasan_kmalloc+0x11c/0x1b0 mm/kasan/common.c:487
kasan_kmalloc+0x9/0x10 mm/kasan/common.c:501
__do_kmalloc mm/slab.c:3655 [inline]
__kmalloc+0x254/0x340 mm/slab.c:3664
kmalloc include/linux/slab.h:557 [inline]
sk_prot_alloc+0xb0/0x290 net/core/sock.c:1603
sk_alloc+0x38/0x950 net/core/sock.c:1657
nr_make_new net/netrom/af_netrom.c:476 [inline]
nr_rx_frame+0xabc/0x1e40 net/netrom/af_netrom.c:959
nr_loopback_timer+0x6a/0x140 net/netrom/nr_loopback.c:59
call_timer_fn+0xec/0x200 kernel/time/timer.c:1322
expire_timers kernel/time/timer.c:1366 [inline]
__run_timers+0x7cd/0x9c0 kernel/time/timer.c:1685
run_timer_softirq+0x4a/0x90 kernel/time/timer.c:1698
__do_softirq+0x333/0x7c4 arch/x86/include/asm/paravirt.h:778
Freed by task 7009:
save_stack mm/kasan/common.c:69 [inline]
set_track mm/kasan/common.c:77 [inline]
__kasan_slab_free+0x12a/0x1e0 mm/kasan/common.c:449
kasan_slab_free+0xe/0x10 mm/kasan/common.c:457
__cache_free mm/slab.c:3425 [inline]
kfree+0x115/0x200 mm/slab.c:3756
sk_prot_free net/core/sock.c:1640 [inline]
__sk_destruct+0x567/0x660 net/core/sock.c:1726
sk_destruct net/core/sock.c:1734 [inline]
__sk_free+0x317/0x3e0 net/core/sock.c:1745
sk_free net/core/sock.c:1756 [inline]
sock_put include/net/sock.h:1725 [inline]
sock_efree+0x60/0x80 net/core/sock.c:2042
skb_release_head_state+0x100/0x220 net/core/skbuff.c:652
skb_release_all net/core/skbuff.c:663 [inline]
__kfree_skb+0x25/0x170 net/core/skbuff.c:679
kfree_skb+0x6f/0xb0 net/core/skbuff.c:697
nr_accept+0x4ef/0x650 net/netrom/af_netrom.c:819
__sys_accept4+0x5bc/0x9a0 net/socket.c:1754
__do_sys_accept net/socket.c:1795 [inline]
__se_sys_accept net/socket.c:1792 [inline]
__x64_sys_accept+0x7d/0x90 net/socket.c:1792
do_syscall_64+0xfe/0x140 arch/x86/entry/common.c:296
entry_SYSCALL_64_after_hwframe+0x49/0xbe
The buggy address belongs to the object at ffff88808b522600
which belongs to the cache kmalloc-2k of size 2048
The buggy address is located 128 bytes inside of
2048-byte region [ffff88808b522600, ffff88808b522e00)
The buggy address belongs to the page:
page:ffffea00022d4880 refcount:1 mapcount:0 mapping:ffff8880aa400e00 index:0x0 compound_mapcount: 0
flags: 0x1fffc0000010200(slab|head)
raw: 01fffc0000010200 ffffea00017d5608 ffffea000183fb88 ffff8880aa400e00
raw: 0000000000000000 ffff88808b522600 0000000100000003 0000000000000000
page dumped because: kasan: bad access detected
Memory state around the buggy address:
ffff88808b522580: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
ffff88808b522600: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
>ffff88808b522680: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
^
ffff88808b522700: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
ffff88808b522780: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
==================================================================
------------[ cut here ]------------
ODEBUG: activate not available (active state 0) object type: timer_list hint: nr_heartbeat_expiry+0x0/0x420 net/netrom/nr_timer.c:193
WARNING: CPU: 0 PID: 6992 at lib/debugobjects.c:484 debug_print_object lib/debugobjects.c:481 [inline]
WARNING: CPU: 0 PID: 6992 at lib/debugobjects.c:484 debug_object_activate+0x33d/0x6f0 lib/debugobjects.c:680
Modules linked in:
CPU: 0 PID: 6992 Comm: syz-executor.5 Tainted: G B 5.3.0-rc1+ #49
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
RIP: 0010:debug_print_object lib/debugobjects.c:481 [inline]
RIP: 0010:debug_object_activate+0x33d/0x6f0 lib/debugobjects.c:680
Code: f7 e8 97 1e 4a fe 4d 8b 06 48 c7 c7 fa 25 88 88 48 c7 c6 80 e5 a0 88 48 c7 c2 23 39 81 88 31 c9 49 89 d9 31 c0 e8 e3 8b e0 fd <0f> 0b 48 ba 00 00 00 00 00 fc ff df ff 05 65 9d 95 05 49 83 c6 20
RSP: 0018:ffff8880aea09928 EFLAGS: 00010046
RAX: d373ee79891ca100 RBX: ffffffff86d74f30 RCX: ffff88805aefc580
RDX: 0000000000000102 RSI: 0000000000000102 RDI: 0000000000000000
RBP: ffff8880aea09970 R08: ffffffff81606214 R09: fffffbfff11fba45
R10: fffffbfff11fba45 R11: 0000000000000000 R12: ffffffff88cd9fc0
R13: ffff88808b5228c8 R14: ffffffff88cd9fc0 R15: ffff88808b5228c8
FS: 00007fc8550ee700(0000) GS:ffff8880aea00000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000000000070f158 CR3: 0000000091af9000 CR4: 00000000001406f0
Call Trace:
debug_timer_activate kernel/time/timer.c:710 [inline]
__mod_timer+0x960/0x16e0 kernel/time/timer.c:1035
mod_timer+0x1f/0x30 kernel/time/timer.c:1096
sk_reset_timer+0x22/0x50 net/core/sock.c:2821
nr_start_heartbeat+0x54/0x60 net/netrom/nr_timer.c:79
nr_rx_frame+0x184c/0x1e40 net/netrom/af_netrom.c:1025
nr_loopback_timer+0x6a/0x140 net/netrom/nr_loopback.c:59
call_timer_fn+0xec/0x200 kernel/time/timer.c:1322
expire_timers kernel/time/timer.c:1366 [inline]
__run_timers+0x7cd/0x9c0 kernel/time/timer.c:1685
run_timer_softirq+0x4a/0x90 kernel/time/timer.c:1698
__do_softirq+0x333/0x7c4 arch/x86/include/asm/paravirt.h:778
invoke_softirq kernel/softirq.c:373 [inline]
irq_exit+0x227/0x230 kernel/softirq.c:413
exiting_irq arch/x86/include/asm/apic.h:537 [inline]
smp_apic_timer_interrupt+0x113/0x280 arch/x86/kernel/apic/apic.c:1095
apic_timer_interrupt+0xf/0x20 arch/x86/entry/entry_64.S:828
RIP: 0010:check_kcov_mode kernel/kcov.c:79 [inline]
RIP: 0010:write_comp_data kernel/kcov.c:123 [inline]
RIP: 0010:__sanitizer_cov_trace_const_cmp8+0x21/0x80 kernel/kcov.c:196
Code: 2e 0f 1f 84 00 00 00 00 00 4c 8b 04 24 65 48 8b 14 25 40 fd 01 00 65 8b 05 a8 1e 8a 7e a9 00 01 1f 00 75 61 8b 82 f0 12 00 00 <83> f8 03 75 56 48 8b 8a f8 12 00 00 44 8b 8a f4 12 00 00 49 c1 e1
RSP: 0018:ffff8880891072b0 EFLAGS: 00000246 ORIG_RAX: ffffffffffffff13
RAX: 0000000000000000 RBX: ffffea000199dec8 RCX: ffff88805aefc580
RDX: ffff88805aefc580 RSI: 0000000000000000 RDI: 0000000000000000
RBP: ffff8880891072f0 R08: ffffffff81a86ba6 R09: fffff94000333bd9
R10: fffff94000333bd9 R11: 0000000000000000 R12: 0000000000000000
R13: dead000000000100 R14: 1ffffd4000333bd9 R15: ffffea000199dec0
zap_pte_range mm/memory.c:1059 [inline]
zap_pmd_range mm/memory.c:1161 [inline]
zap_pud_range mm/memory.c:1190 [inline]
zap_p4d_range mm/memory.c:1211 [inline]
unmap_page_range+0x17e0/0x24e0 mm/memory.c:1232
unmap_single_vma+0x1d4/0x2e0 mm/memory.c:1277
unmap_vmas+0x245/0x380 mm/memory.c:1309
exit_mmap+0x2b7/0x5a0 mm/mmap.c:3145
__mmput+0x120/0x3a0 kernel/fork.c:1064
mmput+0x5d/0x70 kernel/fork.c:1085
exit_mm+0x585/0x640 kernel/exit.c:547
do_exit+0x5d0/0x2340 kernel/exit.c:865
do_group_exit+0x15c/0x2b0 kernel/exit.c:982
get_signal+0x51c/0x1dd0 kernel/signal.c:2728
do_signal+0x7b/0x720 arch/x86/kernel/signal.c:815
exit_to_usermode_loop arch/x86/entry/common.c:159 [inline]
prepare_exit_to_usermode+0x303/0x580 arch/x86/entry/common.c:194
syscall_return_slowpath+0x113/0x4a0 arch/x86/entry/common.c:274
do_syscall_64+0x126/0x140 arch/x86/entry/common.c:299
entry_SYSCALL_64_after_hwframe+0x49/0xbe
RIP: 0033:0x459829
Code: fd b7 fb ff c3 66 2e 0f 1f 84 00 00 00 00 00 66 90 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 0f 83 cb b7 fb ff c3 66 2e 0f 1f 84 00 00 00 00
RSP: 002b:00007fc8550edc78 EFLAGS: 00000246 ORIG_RAX: 0000000000000001
RAX: ffffffffffffffe0 RBX: 0000000000000003 RCX: 0000000000459829
RDX: 000000000000000a RSI: 0000000020000080 RDI: 0000000000000004
RBP: 000000000075bf20 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 00007fc8550ee6d4
R13: 00000000004c9657 R14: 00000000004e09f0 R15: 00000000ffffffff
irq event stamp: 21055
hardirqs last enabled at (21054): [] trace_hardirqs_on_thunk+0x1a/0x20 arch/x86/entry/thunk_64.S:41
hardirqs last disabled at (21055): [] __raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:108 [inline]
hardirqs last disabled at (21055): [] _raw_spin_lock_irqsave+0x7c/0xc0 kernel/locking/spinlock.c:159
softirqs last enabled at (20132): [] invoke_softirq kernel/softirq.c:373 [inline]
softirqs last enabled at (20132): [] irq_exit+0x227/0x230 kernel/softirq.c:413
softirqs last disabled at (20717): [] invoke_softirq kernel/softirq.c:373 [inline]
softirqs last disabled at (20717): [] irq_exit+0x227/0x230 kernel/softirq.c:413
---[ end trace 36bf7fa2113e1649 ]---