========================= WARNING: held lock freed! 5.2.0+ #32 Not tainted ------------------------- syz-executor.1/8501 is freeing memory ffff8880908e95c0-ffff8880908e9dbf, with a lock still held there! 00000000a091dbf5 (sk_lock-AF_NETROM){+.+.}, at: lock_sock include/net/sock.h:1522 [inline] 00000000a091dbf5 (sk_lock-AF_NETROM){+.+.}, at: nr_release+0xfe/0x390 net/netrom/af_netrom.c:522 2 locks held by syz-executor.1/8501: #0: 0000000018589555 (&sb->s_type->i_mutex_key#11){+.+.}, at: inode_lock include/linux/fs.h:778 [inline] #0: 0000000018589555 (&sb->s_type->i_mutex_key#11){+.+.}, at: __sock_release net/socket.c:585 [inline] #0: 0000000018589555 (&sb->s_type->i_mutex_key#11){+.+.}, at: sock_close+0x9e/0x260 net/socket.c:1264 #1: 00000000a091dbf5 (sk_lock-AF_NETROM){+.+.}, at: lock_sock include/net/sock.h:1522 [inline] #1: 00000000a091dbf5 (sk_lock-AF_NETROM){+.+.}, at: nr_release+0xfe/0x390 net/netrom/af_netrom.c:522 stack backtrace: CPU: 0 PID: 8501 Comm: syz-executor.1 Not tainted 5.2.0+ #32 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_freed_lock_bug kernel/locking/lockdep.c:5185 [inline] debug_check_no_locks_freed+0x813/0x990 kernel/locking/lockdep.c:5218 kfree+0xfb/0x200 mm/slab.c:3753 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+0x2a/0x40 net/core/sock.c:1756 sock_put include/net/sock.h:1725 [inline] nr_destroy_socket+0x3e3/0x450 net/netrom/af_netrom.c:288 nr_release+0x191/0x390 net/netrom/af_netrom.c:530 __sock_release net/socket.c:586 [inline] sock_close+0xe1/0x260 net/socket.c:1264 __fput+0x2e4/0x740 fs/file_table.c:280 ____fput+0x15/0x20 fs/file_table.c:313 task_work_run+0x17e/0x1b0 kernel/task_work.c:113 tracehook_notify_resume include/linux/tracehook.h:185 [inline] exit_to_usermode_loop arch/x86/entry/common.c:163 [inline] prepare_exit_to_usermode+0x459/0x580 arch/x86/entry/common.c:194 syscall_return_slowpath+0x110/0x450 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: 0033:0x413501 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:00007ffebb0784a0 EFLAGS: 00000293 ORIG_RAX: 0000000000000003 RAX: 0000000000000000 RBX: 0000000000000007 RCX: 0000000000413501 RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000006 RBP: 0000000000000001 R08: ffffffffffffffff R09: ffffffffffffffff R10: 00007ffebb078580 R11: 0000000000000293 R12: 000000000075c9a0 R13: 000000000075c9a0 R14: 0000000000760ff0 R15: ffffffffffffffff ================================================================== BUG: KASAN: use-after-free in debug_spin_lock_before kernel/locking/spinlock_debug.c:83 [inline] BUG: KASAN: use-after-free in do_raw_spin_lock+0x295/0x3a0 kernel/locking/spinlock_debug.c:112 Read of size 4 at addr ffff8880908e964c by task syz-executor.1/8501 CPU: 1 PID: 8501 Comm: syz-executor.1 Not tainted 5.2.0+ #32 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 __asan_report_load4_noabort+0x14/0x20 mm/kasan/generic_report.c:131 debug_spin_lock_before kernel/locking/spinlock_debug.c:83 [inline] do_raw_spin_lock+0x295/0x3a0 kernel/locking/spinlock_debug.c:112 __raw_spin_lock_bh include/linux/spinlock_api_smp.h:136 [inline] _raw_spin_lock_bh+0x40/0x50 kernel/locking/spinlock.c:175 spin_lock_bh include/linux/spinlock.h:343 [inline] release_sock+0x30/0x1d0 net/core/sock.c:2932 nr_release+0x1b9/0x390 net/netrom/af_netrom.c:553 __sock_release net/socket.c:586 [inline] sock_close+0xe1/0x260 net/socket.c:1264 __fput+0x2e4/0x740 fs/file_table.c:280 ____fput+0x15/0x20 fs/file_table.c:313 task_work_run+0x17e/0x1b0 kernel/task_work.c:113 tracehook_notify_resume include/linux/tracehook.h:185 [inline] exit_to_usermode_loop arch/x86/entry/common.c:163 [inline] prepare_exit_to_usermode+0x459/0x580 arch/x86/entry/common.c:194 syscall_return_slowpath+0x110/0x450 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: 0033:0x413501 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:00007ffebb0784a0 EFLAGS: 00000293 ORIG_RAX: 0000000000000003 RAX: 0000000000000000 RBX: 0000000000000007 RCX: 0000000000413501 RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000006 RBP: 0000000000000001 R08: ffffffffffffffff R09: ffffffffffffffff R10: 00007ffebb078580 R11: 0000000000000293 R12: 000000000075c9a0 R13: 000000000075c9a0 R14: 0000000000760ff0 R15: ffffffffffffffff Allocated by task 0: 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:777 Freed by task 8501: 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+0x2a/0x40 net/core/sock.c:1756 sock_put include/net/sock.h:1725 [inline] nr_destroy_socket+0x3e3/0x450 net/netrom/af_netrom.c:288 nr_release+0x191/0x390 net/netrom/af_netrom.c:530 __sock_release net/socket.c:586 [inline] sock_close+0xe1/0x260 net/socket.c:1264 __fput+0x2e4/0x740 fs/file_table.c:280 ____fput+0x15/0x20 fs/file_table.c:313 task_work_run+0x17e/0x1b0 kernel/task_work.c:113 tracehook_notify_resume include/linux/tracehook.h:185 [inline] exit_to_usermode_loop arch/x86/entry/common.c:163 [inline] prepare_exit_to_usermode+0x459/0x580 arch/x86/entry/common.c:194 syscall_return_slowpath+0x110/0x450 arch/x86/entry/common.c:274 do_syscall_64+0x126/0x140 arch/x86/entry/common.c:299 entry_SYSCALL_64_after_hwframe+0x49/0xbe The buggy address belongs to the object at ffff8880908e95c0 which belongs to the cache kmalloc-2k of size 2048 The buggy address is located 140 bytes inside of 2048-byte region [ffff8880908e95c0, ffff8880908e9dc0) The buggy address belongs to the page: page:ffffea0002423a00 refcount:1 mapcount:0 mapping:ffff8880aa400e00 index:0x0 compound_mapcount: 0 flags: 0x1fffc0000010200(slab|head) raw: 01fffc0000010200 ffffea0002a15508 ffffea000283dc08 ffff8880aa400e00 raw: 0000000000000000 ffff8880908e84c0 0000000100000003 0000000000000000 page dumped because: kasan: bad access detected Memory state around the buggy address: ffff8880908e9500: fb fb fb fb fb fb fb fb fc fc fc fc fc fc fc fc ffff8880908e9580: fc fc fc fc fc fc fc fc fb fb fb fb fb fb fb fb >ffff8880908e9600: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ^ ffff8880908e9680: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff8880908e9700: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ==================================================================