netlink: 104 bytes leftover after parsing attributes in process `syz-executor4'. netlink: 104 bytes leftover after parsing attributes in process `syz-executor4'. ------------[ cut here ]------------ refcount_t: increment on 0; use-after-free. WARNING: CPU: 0 PID: 25457 at lib/refcount.c:153 refcount_inc_checked lib/refcount.c:153 [inline] WARNING: CPU: 0 PID: 25457 at lib/refcount.c:153 refcount_inc_checked+0x61/0x70 lib/refcount.c:151 Kernel panic - not syncing: panic_on_warn set ... CPU: 0 PID: 25457 Comm: syz-executor4 Not tainted 4.20.0+ #16 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+0x1db/0x2d0 lib/dump_stack.c:113 panic+0x2cb/0x589 kernel/panic.c:189 __warn.cold+0x20/0x4b kernel/panic.c:544 report_bug+0x263/0x2b0 lib/bug.c:186 fixup_bug arch/x86/kernel/traps.c:178 [inline] fixup_bug arch/x86/kernel/traps.c:173 [inline] do_error_trap+0x11b/0x200 arch/x86/kernel/traps.c:271 do_invalid_op+0x37/0x50 arch/x86/kernel/traps.c:290 invalid_op+0x14/0x20 arch/x86/entry/entry_64.S:973 RIP: 0010:refcount_inc_checked lib/refcount.c:153 [inline] RIP: 0010:refcount_inc_checked+0x61/0x70 lib/refcount.c:151 Code: 1d 8a 37 c8 06 31 ff 89 de e8 1b 27 f2 fd 84 db 75 dd e8 d2 25 f2 fd 48 c7 c7 e0 97 81 88 c6 05 6a 37 c8 06 01 e8 0f 7d bb fd <0f> 0b eb c1 90 66 2e 0f 1f 84 00 00 00 00 00 55 48 89 e5 41 54 49 RSP: 0018:ffff88806d877138 EFLAGS: 00010286 RAX: 0000000000000000 RBX: 0000000000000000 RCX: ffffc9000bf9d000 RDX: 000000000001d827 RSI: ffffffff816849b6 RDI: 0000000000000005 RBP: ffff88806d877148 R08: ffff8880608260c0 R09: ffff888060826988 R10: ffff8880608260c0 R11: 0000000000000000 R12: ffff88806a024520 R13: ffff888087287c00 R14: ffff88806d8772d0 R15: 0000000000000004 xfrm_pol_hold include/net/xfrm.h:838 [inline] xfrm_policy_bysel_ctx+0x1c9/0x1020 net/xfrm/xfrm_policy.c:1679 xfrm_get_policy+0x67b/0x1160 net/xfrm/xfrm_user.c:1887 xfrm_user_rcv_msg+0x458/0x8d0 net/xfrm/xfrm_user.c:2663 netlink_rcv_skb+0x17d/0x410 net/netlink/af_netlink.c:2477 xfrm_netlink_rcv+0x70/0x90 net/xfrm/xfrm_user.c:2671 netlink_unicast_kernel net/netlink/af_netlink.c:1310 [inline] netlink_unicast+0x574/0x770 net/netlink/af_netlink.c:1336 netlink_sendmsg+0xa05/0xf90 net/netlink/af_netlink.c:1917 sock_sendmsg_nosec net/socket.c:621 [inline] sock_sendmsg+0xdd/0x130 net/socket.c:631 ___sys_sendmsg+0x7ec/0x910 net/socket.c:2116 __sys_sendmsg+0x112/0x270 net/socket.c:2154 __do_sys_sendmsg net/socket.c:2163 [inline] __se_sys_sendmsg net/socket.c:2161 [inline] __x64_sys_sendmsg+0x78/0xb0 net/socket.c:2161 do_syscall_64+0x1a3/0x800 arch/x86/entry/common.c:290 entry_SYSCALL_64_after_hwframe+0x49/0xbe RIP: 0033:0x457ec9 Code: 6d 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 3b b7 fb ff c3 66 2e 0f 1f 84 00 00 00 00 RSP: 002b:00007f6d47b19c78 EFLAGS: 00000246 ORIG_RAX: 000000000000002e RAX: ffffffffffffffda RBX: 0000000000000003 RCX: 0000000000457ec9 RDX: 0000000000000000 RSI: 000000002014f000 RDI: 0000000000000006 RBP: 000000000073bfa0 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 00007f6d47b1a6d4 R13: 00000000004c5394 R14: 00000000004d8e30 R15: 00000000ffffffff Kernel Offset: disabled Rebooting in 86400 seconds..