netlink: 3 bytes leftover after parsing attributes in process `syz-executor3'. netlink: 'syz-executor4': attribute type 25 has an invalid length. netlink: 'syz-executor3': attribute type 6 has an invalid length. ================================================================== BUG: KASAN: slab-out-of-bounds in __write_once_size include/linux/compiler.h:220 [inline] BUG: KASAN: slab-out-of-bounds in __hlist_del include/linux/list.h:702 [inline] BUG: KASAN: slab-out-of-bounds in hlist_del_init include/linux/list.h:717 [inline] BUG: KASAN: slab-out-of-bounds in __xfrm_policy_unlink+0x977/0xa00 net/xfrm/xfrm_policy.c:2213 Write of size 8 at addr ffff8880a79a83e8 by task syz-executor4/28715 CPU: 0 PID: 28715 Comm: syz-executor4 Not tainted 5.0.0-rc3+ #24 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 print_address_description.cold+0x7c/0x20d mm/kasan/report.c:187 kasan_report.cold+0x1b/0x40 mm/kasan/report.c:317 __asan_report_store8_noabort+0x17/0x20 mm/kasan/generic_report.c:140 __write_once_size include/linux/compiler.h:220 [inline] __hlist_del include/linux/list.h:702 [inline] hlist_del_init include/linux/list.h:717 [inline] __xfrm_policy_unlink+0x977/0xa00 net/xfrm/xfrm_policy.c:2213 xfrm_policy_flush+0x331/0x460 net/xfrm/xfrm_policy.c:1789 xfrm_flush_policy+0x166/0x470 net/xfrm/xfrm_user.c:2129 xfrm_user_rcv_msg+0x458/0x8d0 net/xfrm/xfrm_user.c:2663 netlink_rcv_skb+0x17d/0x410 net/netlink/af_netlink.c:2485 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:1925 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: 0033:0x458089 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:00007fc699cf0c78 EFLAGS: 00000246 ORIG_RAX: 000000000000002e RAX: ffffffffffffffda RBX: 0000000000000003 RCX: 0000000000458089 RDX: 0000000020000000 RSI: 000000002014f000 RDI: 0000000000000003 RBP: 000000000073bf00 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 00007fc699cf16d4 R13: 00000000004c568f R14: 00000000004d9400 R15: 00000000ffffffff Allocated by task 26506: save_stack+0x45/0xd0 mm/kasan/common.c:73 set_track mm/kasan/common.c:85 [inline] __kasan_kmalloc mm/kasan/common.c:496 [inline] __kasan_kmalloc.constprop.0+0xcf/0xe0 mm/kasan/common.c:469 kasan_kmalloc+0x9/0x10 mm/kasan/common.c:504 __do_kmalloc mm/slab.c:3711 [inline] __kmalloc+0x15c/0x740 mm/slab.c:3720 kmalloc include/linux/slab.h:550 [inline] kzalloc include/linux/slab.h:740 [inline] neigh_alloc net/core/neighbour.c:402 [inline] ___neigh_create+0x12da/0x2550 net/core/neighbour.c:580 __neigh_create+0x2f/0x40 net/core/neighbour.c:670 ip6_finish_output2+0xa24/0x28e0 net/ipv6/ip6_output.c:117 ip6_finish_output+0x577/0xc30 net/ipv6/ip6_output.c:154 NF_HOOK_COND include/linux/netfilter.h:278 [inline] ip6_output+0x23c/0xa00 net/ipv6/ip6_output.c:171 dst_output include/net/dst.h:444 [inline] NF_HOOK include/linux/netfilter.h:289 [inline] NF_HOOK include/linux/netfilter.h:283 [inline] mld_sendpack+0xa44/0xfd0 net/ipv6/mcast.c:1685 mld_send_cr net/ipv6/mcast.c:1981 [inline] mld_ifc_timer_expire+0x449/0x8a0 net/ipv6/mcast.c:2480 call_timer_fn+0x254/0x900 kernel/time/timer.c:1325 expire_timers kernel/time/timer.c:1362 [inline] __run_timers+0x6fc/0xd50 kernel/time/timer.c:1681 run_timer_softirq+0x52/0xb0 kernel/time/timer.c:1694 __do_softirq+0x30b/0xb11 kernel/softirq.c:292 Freed by task 24783: save_stack+0x45/0xd0 mm/kasan/common.c:73 set_track mm/kasan/common.c:85 [inline] __kasan_slab_free+0x102/0x150 mm/kasan/common.c:458 kasan_slab_free+0xe/0x10 mm/kasan/common.c:466 __cache_free mm/slab.c:3487 [inline] kfree+0xcf/0x230 mm/slab.c:3806 skb_free_head+0x93/0xb0 net/core/skbuff.c:553 skb_release_data+0x6ea/0x970 net/core/skbuff.c:573 skb_release_all+0x4d/0x60 net/core/skbuff.c:627 __kfree_skb+0x16/0x30 net/core/skbuff.c:641 sk_eat_skb include/net/sock.h:2429 [inline] tcp_recvmsg+0x14d9/0x3270 net/ipv4/tcp.c:2144 inet_recvmsg+0x17b/0x6d0 net/ipv4/af_inet.c:830 sock_recvmsg_nosec net/socket.c:794 [inline] sock_recvmsg net/socket.c:801 [inline] sock_recvmsg+0xd0/0x110 net/socket.c:797 ___sys_recvmsg+0x2a8/0x680 net/socket.c:2278 __sys_recvmsg+0x10f/0x270 net/socket.c:2327 __do_sys_recvmsg net/socket.c:2337 [inline] __se_sys_recvmsg net/socket.c:2334 [inline] __x64_sys_recvmsg+0x78/0xb0 net/socket.c:2334 do_syscall_64+0x1a3/0x800 arch/x86/entry/common.c:290 entry_SYSCALL_64_after_hwframe+0x49/0xbe The buggy address belongs to the object at ffff8880a79a8040 which belongs to the cache kmalloc-1k of size 1024 The buggy address is located 936 bytes inside of 1024-byte region [ffff8880a79a8040, ffff8880a79a8440) The buggy address belongs to the page: page:ffffea00029e6a00 count:1 mapcount:0 mapping:ffff88812c3f0ac0 index:0x0 compound_mapcount: 0 flags: 0x1fffc0000010200(slab|head) raw: 01fffc0000010200 ffffea000235ad88 ffffea0001a6f108 ffff88812c3f0ac0 raw: 0000000000000000 ffff8880a79a8040 0000000100000007 0000000000000000 page dumped because: kasan: bad access detected Memory state around the buggy address: ffff8880a79a8280: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ffff8880a79a8300: 00 fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc >ffff8880a79a8380: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ^ ffff8880a79a8400: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ffff8880a79a8480: fc fc fc fc fc fc fc fc fb fb fb fb fb fb fb fb ==================================================================