================================================================== 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 ffff888095650b00 by task syz-executor.1/18793 CPU: 0 PID: 18793 Comm: syz-executor.1 Not tainted 5.2.0+ #64 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+0x16f/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] nr_release+0x62/0x3e0 /net/netrom/af_netrom.c:520 __sock_release+0xce/0x280 /net/socket.c:590 sock_close+0x1e/0x30 /net/socket.c:1268 __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+0x5a9/0x6a0 /arch/x86/entry/common.c:299 entry_SYSCALL_64_after_hwframe+0x49/0xbe RIP: 0033:0x459819 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:00007f60a3575c78 EFLAGS: 00000246 ORIG_RAX: 0000000000000021 RAX: 0000000000000004 RBX: 0000000000000002 RCX: 0000000000459819 RDX: 0000000000000000 RSI: 0000000000000004 RDI: 0000000000000003 RBP: 000000000075bf20 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 00007f60a35766d4 R13: 00000000004bfe9c R14: 00000000004d1b28 R15: 00000000ffffffff Allocated by task 18787: 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+0x163/0x760 /mm/slab.c:3664 kmalloc /./include/linux/slab.h:557 [inline] sk_prot_alloc+0x23a/0x310 /net/core/sock.c:1603 sk_alloc+0x39/0xf60 /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/0x700 /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+0x66c/0x16a0 /kernel/time/timer.c:1698 __do_softirq+0x30d/0x970 /kernel/softirq.c:292 Freed by task 18795: 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/0x2a0 /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+0x101/0x380 /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_accept /net/socket.c:1795 [inline] __se_sys_accept /net/socket.c:1792 [inline] __x64_sys_accept+0x75/0xb0 /net/socket.c:1792 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 ffff888095650a80 which belongs to the cache kmalloc-2k of size 2048 The buggy address is located 128 bytes inside of 2048-byte region [ffff888095650a80, ffff888095651280) The buggy address belongs to the page: page:ffffea0002559400 refcount:1 mapcount:0 mapping:ffff8880aa400e00 index:0x0 compound_mapcount: 0 flags: 0x1fffc0000010200(slab|head) raw: 01fffc0000010200 ffffea00012c5688 ffff8880aa401948 ffff8880aa400e00 raw: 0000000000000000 ffff888095650200 0000000100000003 0000000000000000 page dumped because: kasan: bad access detected Memory state around the buggy address: ffff888095650a00: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ffff888095650a80: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb >ffff888095650b00: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ^ ffff888095650b80: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff888095650c00: 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_t1timer_expiry+0x0/0x340 /net/netrom/nr_timer.c:157 WARNING: CPU: 0 PID: 18793 at lib/debugobjects.c:481 debug_print_object+0x168/0x250 /lib/debugobjects.c:481 Modules linked in: CPU: 0 PID: 18793 Comm: syz-executor.1 Tainted: G B 5.2.0+ #64 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 RIP: 0010:debug_print_object+0x168/0x250 /lib/debugobjects.c:481 Code: dd 80 02 c6 87 48 89 fa 48 c1 ea 03 80 3c 02 00 0f 85 b5 00 00 00 48 8b 14 dd 80 02 c6 87 48 c7 c7 80 f7 c5 87 e8 60 0d 09 fe <0f> 0b 83 05 e3 68 6a 06 01 48 83 c4 20 5b 41 5c 41 5d 41 5e 5d c3 RSP: 0018:ffff88804a10faf0 EFLAGS: 00010082 RAX: 0000000000000000 RBX: 0000000000000005 RCX: 0000000000000000 RDX: 0000000000040000 RSI: ffffffff815b9de2 RDI: ffffed1009421f50 RBP: ffff88804a10fb30 R08: ffff88805cf34080 R09: fffffbfff13494e8 R10: fffffbfff13494e7 R11: ffffffff89a4a73f R12: 0000000000000001 R13: ffffffff88db3f40 R14: ffffffff8160d430 R15: 1ffff11009421f6c FS: 00007f60a3576700(0000) GS:ffff8880ae800000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000000001a5b668 CR3: 000000005b09a000 CR4: 00000000001426f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000ffff0ff0 DR7: 0000000000000600 Call Trace: debug_object_activate+0x2e5/0x470 /lib/debugobjects.c:680 debug_timer_activate /kernel/time/timer.c:710 [inline] __mod_timer /kernel/time/timer.c:1035 [inline] mod_timer+0x415/0xb90 /kernel/time/timer.c:1096 sk_reset_timer+0x24/0x60 /net/core/sock.c:2821 nr_start_t1timer+0x6e/0xa0 /net/netrom/nr_timer.c:52 nr_release+0x1de/0x3e0 /net/netrom/af_netrom.c:537 __sock_release+0xce/0x280 /net/socket.c:590 sock_close+0x1e/0x30 /net/socket.c:1268 __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+0x5a9/0x6a0 /arch/x86/entry/common.c:299 entry_SYSCALL_64_after_hwframe+0x49/0xbe RIP: 0033:0x459819 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:00007f60a3575c78 EFLAGS: 00000246 ORIG_RAX: 0000000000000021 RAX: 0000000000000004 RBX: 0000000000000002 RCX: 0000000000459819 RDX: 0000000000000000 RSI: 0000000000000004 RDI: 0000000000000003 RBP: 000000000075bf20 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 00007f60a35766d4 R13: 00000000004bfe9c R14: 00000000004d1b28 R15: 00000000ffffffff irq event stamp: 458 hardirqs last enabled at (457): [] __raw_spin_unlock_irq /./include/linux/spinlock_api_smp.h:168 [inline] hardirqs last enabled at (457): [] _raw_spin_unlock_irq+0x28/0x70 /kernel/locking/spinlock.c:199 hardirqs last disabled at (458): [] __raw_spin_lock_irqsave /./include/linux/spinlock_api_smp.h:108 [inline] hardirqs last disabled at (458): [] _raw_spin_lock_irqsave+0x6f/0xd0 /kernel/locking/spinlock.c:159 softirqs last enabled at (426): [] spin_unlock_bh /./include/linux/spinlock.h:383 [inline] softirqs last enabled at (426): [] release_sock+0x156/0x1c0 /net/core/sock.c:2945 softirqs last disabled at (424): [] spin_lock_bh /./include/linux/spinlock.h:343 [inline] softirqs last disabled at (424): [] release_sock+0x20/0x1c0 /net/core/sock.c:2932 ---[ end trace b40b12e836c72ce1 ]--- ------------[ cut here ]------------ ODEBUG: assert_init not available (active state 0) object type: timer_list hint: nr_t2timer_expiry+0x0/0xb0 /net/netrom/nr_timer.c:170 WARNING: CPU: 0 PID: 18793 at lib/debugobjects.c:481 debug_print_object+0x168/0x250 /lib/debugobjects.c:481 Modules linked in: CPU: 0 PID: 18793 Comm: syz-executor.1 Tainted: G B W 5.2.0+ #64 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 RIP: 0010:debug_print_object+0x168/0x250 /lib/debugobjects.c:481 Code: dd 80 02 c6 87 48 89 fa 48 c1 ea 03 80 3c 02 00 0f 85 b5 00 00 00 48 8b 14 dd 80 02 c6 87 48 c7 c7 80 f7 c5 87 e8 60 0d 09 fe <0f> 0b 83 05 e3 68 6a 06 01 48 83 c4 20 5b 41 5c 41 5d 41 5e 5d c3 RSP: 0018:ffff88804a10fb40 EFLAGS: 00010282 RAX: 0000000000000000 RBX: 0000000000000005 RCX: 0000000000000000 RDX: 0000000000040000 RSI: ffffffff815b9de2 RDI: ffffed1009421f5a RBP: ffff88804a10fb80 R08: ffff88805cf34080 R09: fffffbfff13494e8 R10: fffffbfff13494e7 R11: ffffffff89a4a73f R12: 0000000000000002 R13: ffffffff88db3f40 R14: ffffffff8160d430 R15: ffff888095650fa0 FS: 00007f60a3576700(0000) GS:ffff8880ae800000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000000001a5b668 CR3: 000000005b09a000 CR4: 00000000001426f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000ffff0ff0 DR7: 0000000000000600 Call Trace: debug_object_assert_init /lib/debugobjects.c:866 [inline] debug_object_assert_init+0x23a/0x2f0 /lib/debugobjects.c:837 debug_timer_assert_init /kernel/time/timer.c:725 [inline] debug_assert_init /kernel/time/timer.c:770 [inline] del_timer+0x7c/0x120 /kernel/time/timer.c:1192 sk_stop_timer+0x1c/0x60 /net/core/sock.c:2828 nr_stop_t2timer+0x1e/0x30 /net/netrom/nr_timer.c:89 nr_release+0x1e6/0x3e0 /net/netrom/af_netrom.c:538 __sock_release+0xce/0x280 /net/socket.c:590 sock_close+0x1e/0x30 /net/socket.c:1268 __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+0x5a9/0x6a0 /arch/x86/entry/common.c:299 entry_SYSCALL_64_after_hwframe+0x49/0xbe RIP: 0033:0x459819 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:00007f60a3575c78 EFLAGS: 00000246 ORIG_RAX: 0000000000000021 RAX: 0000000000000004 RBX: 0000000000000002 RCX: 0000000000459819 RDX: 0000000000000000 RSI: 0000000000000004 RDI: 0000000000000003 RBP: 000000000075bf20 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 00007f60a35766d4 R13: 00000000004bfe9c R14: 00000000004d1b28 R15: 00000000ffffffff irq event stamp: 458 hardirqs last enabled at (457): [] __raw_spin_unlock_irq /./include/linux/spinlock_api_smp.h:168 [inline] hardirqs last enabled at (457): [] _raw_spin_unlock_irq+0x28/0x70 /kernel/locking/spinlock.c:199 hardirqs last disabled at (458): [] __raw_spin_lock_irqsave /./include/linux/spinlock_api_smp.h:108 [inline] hardirqs last disabled at (458): [] _raw_spin_lock_irqsave+0x6f/0xd0 /kernel/locking/spinlock.c:159 softirqs last enabled at (426): [] spin_unlock_bh /./include/linux/spinlock.h:383 [inline] softirqs last enabled at (426): [] release_sock+0x156/0x1c0 /net/core/sock.c:2945 softirqs last disabled at (424): [] spin_lock_bh /./include/linux/spinlock.h:343 [inline] softirqs last disabled at (424): [] release_sock+0x20/0x1c0 /net/core/sock.c:2932 ---[ end trace b40b12e836c72ce2 ]---