================================================================== BUG: KASAN: slab-out-of-bounds in __write_once_size include/linux/compiler.h:218 [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 ffff8880996f9a28 by task syz-executor1/3010 CPU: 0 PID: 3010 Comm: syz-executor1 Not tainted 4.20.0+ #3 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:256 kasan_report_error mm/kasan/report.c:354 [inline] kasan_report mm/kasan/report.c:412 [inline] kasan_report.cold+0x8c/0x2ba mm/kasan/report.c:396 __asan_report_store8_noabort+0x17/0x20 mm/kasan/report.c:438 __write_once_size include/linux/compiler.h:218 [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 pfkey_spdflush+0xaf/0x3c0 net/key/af_key.c:2785 pfkey_process+0x6d2/0x810 net/key/af_key.c:2844 pfkey_sendmsg+0x5bb/0xfc0 net/key/af_key.c:3683 sock_sendmsg_nosec net/socket.c:621 [inline] sock_sendmsg+0xdd/0x130 net/socket.c:631 audit: type=1804 audit(1546891171.448:593): pid=3019 uid=0 auid=4294967295 ses=4294967295 subj==unconfined op=invalid_pcr cause=open_writers comm="syz-executor2" name="/root/syzkaller-testdir414689926/syzkaller.KtNq00/667/memory.events" dev="sda1" ino=16913 res=1 ___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:00007faab2ac7c78 EFLAGS: 00000246 ORIG_RAX: 000000000000002e RAX: ffffffffffffffda RBX: 0000000000000003 RCX: 0000000000457ec9 RDX: 0000000000000000 RSI: 00000000200000c0 RDI: 0000000000000004 RBP: 000000000073bf00 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 00007faab2ac86d4 R13: 00000000004c5305 R14: 00000000004d8d70 R15: 00000000ffffffff Allocated by task 2581: save_stack+0x45/0xd0 mm/kasan/kasan.c:448 set_track mm/kasan/kasan.c:460 [inline] kasan_kmalloc mm/kasan/kasan.c:553 [inline] kasan_kmalloc+0xce/0xf0 mm/kasan/kasan.c:531 __do_kmalloc_node mm/slab.c:3684 [inline] __kmalloc_node_track_caller+0x51/0x80 mm/slab.c:3698 __kmalloc_reserve.isra.0+0x40/0xe0 net/core/skbuff.c:140 __alloc_skb+0x12d/0x730 net/core/skbuff.c:208 alloc_skb include/linux/skbuff.h:1011 [inline] netlink_dump+0x7be/0x1070 net/netlink/af_netlink.c:2224 __netlink_dump_start+0x5b4/0x7e0 net/netlink/af_netlink.c:2352 netlink_dump_start include/linux/netlink.h:225 [inline] ctnetlink_get_conntrack+0x76d/0x9f0 net/netfilter/nf_conntrack_netlink.c:1325 nfnetlink_rcv_msg+0xdd0/0x10b0 net/netfilter/nfnetlink.c:228 netlink_rcv_skb+0x17d/0x410 net/netlink/af_netlink.c:2477 nfnetlink_rcv+0x1ba/0x4c0 net/netfilter/nfnetlink.c:560 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 Freed by task 7931: save_stack+0x45/0xd0 mm/kasan/kasan.c:448 set_track mm/kasan/kasan.c:460 [inline] __kasan_slab_free+0x102/0x150 mm/kasan/kasan.c:521 kasan_slab_free+0xe/0x10 mm/kasan/kasan.c:528 __cache_free mm/slab.c:3498 [inline] kfree+0xcf/0x230 mm/slab.c:3817 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 net/core/skbuff.c:641 [inline] kfree_skb net/core/skbuff.c:659 [inline] kfree_skb+0x199/0x580 net/core/skbuff.c:653 skb_queue_purge+0x19/0x40 net/core/skbuff.c:2902 netlink_sock_destruct+0x178/0x410 net/netlink/af_netlink.c:403 __sk_destruct+0xd2/0xa60 net/core/sock.c:1569 sk_destruct+0x7b/0x90 net/core/sock.c:1604 kobject: 'loop5' (00000000a8a771ef): kobject_uevent_env __sk_free+0xce/0x300 net/core/sock.c:1615 sk_free+0x42/0x50 net/core/sock.c:1626 netlink_sock_destruct_work+0x19/0x20 net/netlink/af_netlink.c:420 process_one_work+0xd0c/0x1ce0 kernel/workqueue.c:2153 worker_thread+0x143/0x14a0 kernel/workqueue.c:2296 kobject: 'loop5' (00000000a8a771ef): fill_kobj_path: path = '/devices/virtual/block/loop5' kthread+0x357/0x430 kernel/kthread.c:246 ret_from_fork+0x3a/0x50 arch/x86/entry/entry_64.S:352 The buggy address belongs to the object at ffff8880996f8080 which belongs to the cache kmalloc-4k of size 4096 The buggy address is located 2472 bytes to the right of 4096-byte region [ffff8880996f8080, ffff8880996f9080) The buggy address belongs to the page: page:ffffea000265be00 count:1 mapcount:0 mapping:ffff88812c3f0dc0 index:0x0 compound_mapcount: 0 flags: 0x1fffc0000010200(slab|head) raw: 01fffc0000010200 ffffea0001b48488 ffffea000242e208 ffff88812c3f0dc0 raw: 0000000000000000 ffff8880996f8080 0000000100000001 0000000000000000 page dumped because: kasan: bad access detected Memory state around the buggy address: ffff8880996f9900: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc kobject: 'loop0' (0000000007847ade): kobject_uevent_env ffff8880996f9980: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc >ffff8880996f9a00: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ^ ffff8880996f9a80: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ffff8880996f9b00: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ==================================================================