================================================================== 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 ffff888061e43600 by task syz-executor.1/12524 CPU: 0 PID: 12524 Comm: syz-executor.1 Not tainted 5.2.0-rc3+ #50 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:649 [inline] nr_release+0x62/0x3b0 net/netrom/af_netrom.c:520 __sock_release+0xce/0x2a0 net/socket.c:601 sock_close+0x1b/0x30 net/socket.c:1273 __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 exit_task_work include/linux/task_work.h:22 [inline] do_exit+0x90a/0x2fa0 kernel/exit.c:877 do_group_exit+0x135/0x370 kernel/exit.c:981 get_signal+0x471/0x24b0 kernel/signal.c:2640 do_signal+0x87/0x1900 arch/x86/kernel/signal.c:815 exit_to_usermode_loop+0x244/0x2c0 arch/x86/entry/common.c:164 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: 0033:0x412fb1 Code: 00 80 3e 40 00 00 00 00 00 80 3e 40 00 00 00 00 00 80 3e 40 00 00 00 00 00 40 3e 40 00 00 00 00 00 30 3e 40 00 00 00 00 00 30 <3e> 40 00 00 00 00 00 20 3e 40 00 00 00 00 00 f0 3d 40 00 00 00 00 RSP: 002b:00007fff6b317c10 EFLAGS: 00000293 ORIG_RAX: 0000000000000003 RAX: 0000000000000000 RBX: 0000000000000004 RCX: 0000000000412fb1 RDX: 0000001b2cd20000 RSI: 00000000000017f8 RDI: 0000000000000003 RBP: 0000000000000001 R08: 00000000a5a157f8 R09: 00000000a5a157fc R10: 00007fff6b317cf0 R11: 0000000000000293 R12: 000000000075c9a0 R13: 000000000075c9a0 R14: 00000000001c61aa R15: 000000000075c124 Allocated by task 12591: 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:1602 sk_alloc+0x39/0xf70 net/core/sock.c:1656 nr_create+0xb9/0x5e0 net/netrom/af_netrom.c:433 __sock_create+0x3d8/0x730 net/socket.c:1424 sock_create net/socket.c:1475 [inline] __sys_socket+0x103/0x220 net/socket.c:1517 __do_sys_socket net/socket.c:1526 [inline] __se_sys_socket net/socket.c:1524 [inline] __x64_sys_socket+0x73/0xb0 net/socket.c:1524 do_syscall_64+0xfd/0x680 arch/x86/entry/common.c:301 entry_SYSCALL_64_after_hwframe+0x49/0xbe Freed by task 12524: 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:1639 [inline] __sk_destruct+0x4f7/0x6e0 net/core/sock.c:1725 sk_destruct+0x7b/0x90 net/core/sock.c:1733 __sk_free+0xce/0x300 net/core/sock.c:1744 sk_free+0x42/0x50 net/core/sock.c:1755 sock_put include/net/sock.h:1723 [inline] nr_release+0x332/0x3b0 net/netrom/af_netrom.c:554 __sock_release+0xce/0x2a0 net/socket.c:601 sock_close+0x1b/0x30 net/socket.c:1273 __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 exit_task_work include/linux/task_work.h:22 [inline] do_exit+0x90a/0x2fa0 kernel/exit.c:877 do_group_exit+0x135/0x370 kernel/exit.c:981 get_signal+0x471/0x24b0 kernel/signal.c:2640 do_signal+0x87/0x1900 arch/x86/kernel/signal.c:815 exit_to_usermode_loop+0x244/0x2c0 arch/x86/entry/common.c:164 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 ffff888061e43580 which belongs to the cache kmalloc-2k of size 2048 The buggy address is located 128 bytes inside of 2048-byte region [ffff888061e43580, ffff888061e43d80) The buggy address belongs to the page: page:ffffea0001879080 refcount:1 mapcount:0 mapping:ffff8880aa400c40 index:0x0 compound_mapcount: 0 flags: 0x1fffc0000010200(slab|head) raw: 01fffc0000010200 ffffea0001925888 ffffea00026b9888 ffff8880aa400c40 raw: 0000000000000000 ffff888061e42480 0000000100000003 0000000000000000 page dumped because: kasan: bad access detected Memory state around the buggy address: ffff888061e43500: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ffff888061e43580: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb >ffff888061e43600: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ^ ffff888061e43680: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff888061e43700: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ==================================================================