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BUG: KASAN: use-after-free in xfrm_policy_insert_inexact_list net/xfrm/xfrm_policy.c:1497 [inline]
BUG: KASAN: use-after-free in xfrm_policy_inexact_insert+0xbfa/0xda0 net/xfrm/xfrm_policy.c:1202
Read of size 1 at addr ffff888037a68b59 by task syz-executor3/5700

CPU: 1 PID: 5700 Comm: syz-executor3 Not tainted 5.0.0-rc3+ #15
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_load1_noabort+0x14/0x20 mm/kasan/generic_report.c:132
 xfrm_policy_insert_inexact_list net/xfrm/xfrm_policy.c:1497 [inline]
 xfrm_policy_inexact_insert+0xbfa/0xda0 net/xfrm/xfrm_policy.c:1202
 xfrm_policy_insert+0x623/0x910 net/xfrm/xfrm_policy.c:1570
 xfrm_add_policy+0x2a1/0x6c0 net/xfrm/xfrm_user.c:1657
 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: 0033:0x458099
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:00007f3e66880c78 EFLAGS: 00000246 ORIG_RAX: 000000000000002e
RAX: ffffffffffffffda RBX: 0000000000000003 RCX: 0000000000458099
RDX: 0000000000000000 RSI: 000000002014f000 RDI: 0000000000000005
RBP: 000000000073bf00 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 00007f3e668816d4
R13: 00000000004c562b R14: 00000000004d9298 R15: 00000000ffffffff

Allocated by task 3867:
 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_node mm/slab.c:3673 [inline]
 __kmalloc_node_track_caller+0x4e/0x70 mm/slab.c:3687
 __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_alloc_large_skb net/netlink/af_netlink.c:1182 [inline]
 netlink_sendmsg+0xb11/0xf90 net/netlink/af_netlink.c:1900
 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 8701:
 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 net/core/skbuff.c:641 [inline]
 consume_skb net/core/skbuff.c:701 [inline]
 consume_skb+0x18c/0x550 net/core/skbuff.c:695
 skb_free_datagram+0x1b/0x100 net/core/datagram.c:329
 netlink_recvmsg+0x716/0x1510 net/netlink/af_netlink.c:2004
 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 ffff888037a68940
 which belongs to the cache kmalloc-1k of size 1024
The buggy address is located 537 bytes inside of
 1024-byte region [ffff888037a68940, ffff888037a68d40)
The buggy address belongs to the page:
page:ffffea0000de9a00 count:1 mapcount:0 mapping:ffff88812c3f0ac0 index:0x0 compound_mapcount: 0
flags: 0x1fffc0000010200(slab|head)
raw: 01fffc0000010200 ffffea0001976388 ffffea000285bd88 ffff88812c3f0ac0
raw: 0000000000000000 ffff888037a68040 0000000100000007 0000000000000000
page dumped because: kasan: bad access detected

Memory state around the buggy address:
 ffff888037a68a00: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
 ffff888037a68a80: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
>ffff888037a68b00: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
                                                    ^
 ffff888037a68b80: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
 ffff888037a68c00: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
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