================================================================== 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 ffff888069c8b740 by task syz-executor.0/21266 CPU: 0 PID: 21266 Comm: syz-executor.0 Not tainted 5.2.0-rc2+ #43 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.cold+0x7c/0x20d mm/kasan/report.c:188 __kasan_report.cold+0x1b/0x40 mm/kasan/report.c:317 kasan_report+0x12/0x20 mm/kasan/common.c:614 check_memory_region_inline mm/kasan/generic.c:185 [inline] check_memory_region+0x123/0x190 mm/kasan/generic.c:191 kasan_check_read+0x11/0x20 mm/kasan/common.c:94 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:654 [inline] nr_release+0x62/0x3b0 net/netrom/af_netrom.c:523 __sock_release+0xce/0x2a0 net/socket.c:607 sock_close+0x1b/0x30 net/socket.c:1279 __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+0x273/0x2c0 arch/x86/entry/common.c:168 prepare_exit_to_usermode arch/x86/entry/common.c:199 [inline] syscall_return_slowpath arch/x86/entry/common.c:279 [inline] do_syscall_64+0x58e/0x680 arch/x86/entry/common.c:304 entry_SYSCALL_64_after_hwframe+0x49/0xbe RIP: 0033:0x412f61 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:00007fff5193a2c0 EFLAGS: 00000293 ORIG_RAX: 0000000000000003 RAX: 0000000000000000 RBX: 0000000000000007 RCX: 0000000000412f61 RDX: 0000000000000000 RSI: 0000000000001f3d RDI: 0000000000000006 RBP: 0000000000000001 R08: 0000000017981f3d R09: 0000000017981f41 R10: 00007fff5193a3a0 R11: 0000000000000293 R12: 000000000075c920 R13: 000000000075c920 R14: 000000000005d89d R15: 000000000075c06c Allocated by task 21267: save_stack+0x23/0x90 mm/kasan/common.c:71 set_track mm/kasan/common.c:79 [inline] __kasan_kmalloc mm/kasan/common.c:489 [inline] __kasan_kmalloc.constprop.0+0xcf/0xe0 mm/kasan/common.c:462 kasan_kmalloc+0x9/0x10 mm/kasan/common.c:503 __do_kmalloc mm/slab.c:3660 [inline] __kmalloc+0x15c/0x740 mm/slab.c:3669 kmalloc include/linux/slab.h:552 [inline] sk_prot_alloc+0x19c/0x2e0 net/core/sock.c:1608 sk_alloc+0x39/0xf70 net/core/sock.c:1662 nr_create+0xb9/0x5e0 net/netrom/af_netrom.c:436 __sock_create+0x3d8/0x730 net/socket.c:1430 sock_create net/socket.c:1481 [inline] __sys_socket+0x103/0x220 net/socket.c:1523 __do_sys_socket net/socket.c:1532 [inline] __se_sys_socket net/socket.c:1530 [inline] __x64_sys_socket+0x73/0xb0 net/socket.c:1530 do_syscall_64+0xfd/0x680 arch/x86/entry/common.c:301 entry_SYSCALL_64_after_hwframe+0x49/0xbe Freed by task 21266: save_stack+0x23/0x90 mm/kasan/common.c:71 set_track mm/kasan/common.c:79 [inline] __kasan_slab_free+0x102/0x150 mm/kasan/common.c:451 kasan_slab_free+0xe/0x10 mm/kasan/common.c:459 __cache_free mm/slab.c:3432 [inline] kfree+0xcf/0x220 mm/slab.c:3755 sk_prot_free net/core/sock.c:1645 [inline] __sk_destruct+0x4f7/0x6e0 net/core/sock.c:1731 sk_destruct+0x7b/0x90 net/core/sock.c:1739 __sk_free+0xce/0x300 net/core/sock.c:1750 sk_free+0x42/0x50 net/core/sock.c:1761 sock_put include/net/sock.h:1728 [inline] nr_release+0x332/0x3b0 net/netrom/af_netrom.c:557 __sock_release+0xce/0x2a0 net/socket.c:607 sock_close+0x1b/0x30 net/socket.c:1279 __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+0x273/0x2c0 arch/x86/entry/common.c:168 prepare_exit_to_usermode arch/x86/entry/common.c:199 [inline] syscall_return_slowpath arch/x86/entry/common.c:279 [inline] do_syscall_64+0x58e/0x680 arch/x86/entry/common.c:304 entry_SYSCALL_64_after_hwframe+0x49/0xbe The buggy address belongs to the object at ffff888069c8b6c0 which belongs to the cache kmalloc-2k of size 2048 The buggy address is located 128 bytes inside of 2048-byte region [ffff888069c8b6c0, ffff888069c8bec0) The buggy address belongs to the page: page:ffffea0001a72280 refcount:1 mapcount:0 mapping:ffff8880aa400c40 index:0x0 compound_mapcount: 0 flags: 0x1fffc0000010200(slab|head) raw: 01fffc0000010200 ffffea0001a43388 ffffea00026c1708 ffff8880aa400c40 raw: 0000000000000000 ffff888069c8a5c0 0000000100000003 0000000000000000 page dumped because: kasan: bad access detected Memory state around the buggy address: ffff888069c8b600: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ffff888069c8b680: fc fc fc fc fc fc fc fc fb fb fb fb fb fb fb fb >ffff888069c8b700: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ^ ffff888069c8b780: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff888069c8b800: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ==================================================================