================================================================== BUG: KASAN: use-after-free in __hlist_del include/linux/list.h:676 [inline] BUG: KASAN: use-after-free in hlist_del_rcu include/linux/rculist.h:427 [inline] BUG: KASAN: use-after-free in vxlan_fdb_destroy drivers/net/vxlan.c:787 [inline] BUG: KASAN: use-after-free in __vxlan_dev_create+0x8dc/0x970 drivers/net/vxlan.c:3278 Read of size 8 at addr ffff8880469a9380 by task syz-executor.0/26084 CPU: 1 PID: 26084 Comm: syz-executor.0 Not tainted 4.14.198-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Call Trace: __dump_stack lib/dump_stack.c:17 [inline] dump_stack+0x1b2/0x283 lib/dump_stack.c:58 print_address_description.cold+0x54/0x1d3 mm/kasan/report.c:252 kasan_report_error.cold+0x8a/0x194 mm/kasan/report.c:351 kasan_report mm/kasan/report.c:409 [inline] __asan_report_load8_noabort+0x68/0x70 mm/kasan/report.c:430 __hlist_del include/linux/list.h:676 [inline] hlist_del_rcu include/linux/rculist.h:427 [inline] vxlan_fdb_destroy drivers/net/vxlan.c:787 [inline] __vxlan_dev_create+0x8dc/0x970 drivers/net/vxlan.c:3278 vxlan_newlink+0xa3/0xe0 drivers/net/vxlan.c:3499 rtnl_newlink+0xf88/0x1830 net/core/rtnetlink.c:2728 rtnetlink_rcv_msg+0x3be/0xb10 net/core/rtnetlink.c:4316 netlink_rcv_skb+0x125/0x390 net/netlink/af_netlink.c:2433 netlink_unicast_kernel net/netlink/af_netlink.c:1287 [inline] netlink_unicast+0x437/0x610 net/netlink/af_netlink.c:1313 netlink_sendmsg+0x62e/0xb80 net/netlink/af_netlink.c:1878 sock_sendmsg_nosec net/socket.c:646 [inline] sock_sendmsg+0xb5/0x100 net/socket.c:656 sock_no_sendpage+0xe2/0x110 net/core/sock.c:2595 kernel_sendpage net/socket.c:3407 [inline] sock_sendpage+0xdf/0x140 net/socket.c:871 pipe_to_sendpage+0x226/0x2d0 fs/splice.c:451 splice_from_pipe_feed fs/splice.c:502 [inline] __splice_from_pipe+0x326/0x7a0 fs/splice.c:626 splice_from_pipe fs/splice.c:661 [inline] generic_splice_sendpage+0xc1/0x110 fs/splice.c:832 do_splice_from fs/splice.c:851 [inline] do_splice fs/splice.c:1147 [inline] SYSC_splice fs/splice.c:1402 [inline] SyS_splice+0xd59/0x1380 fs/splice.c:1382 do_syscall_64+0x1d5/0x640 arch/x86/entry/common.c:292 entry_SYSCALL_64_after_hwframe+0x46/0xbb RIP: 0033:0x45e179 RSP: 002b:00007f24b52bcc78 EFLAGS: 00000246 ORIG_RAX: 0000000000000113 RAX: ffffffffffffffda RBX: 0000000000033ec0 RCX: 000000000045e179 RDX: 0000000000000007 RSI: 0000000000000000 RDI: 0000000000000005 RBP: 000000000118d040 R08: 000000000004ffe2 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 000000000118cff4 R13: 00007ffec34330af R14: 00007f24b52bd9c0 R15: 000000000118cff4 Allocated by task 26084: save_stack mm/kasan/kasan.c:447 [inline] set_track mm/kasan/kasan.c:459 [inline] kasan_kmalloc+0xeb/0x160 mm/kasan/kasan.c:551 kmem_cache_alloc_trace+0x131/0x3d0 mm/slab.c:3618 kmalloc include/linux/slab.h:488 [inline] vxlan_fdb_alloc drivers/net/vxlan.c:645 [inline] vxlan_fdb_create+0x11a/0x5d0 drivers/net/vxlan.c:673 __vxlan_dev_create+0x370/0x970 drivers/net/vxlan.c:3244 vxlan_newlink+0xa3/0xe0 drivers/net/vxlan.c:3499 rtnl_newlink+0xf88/0x1830 net/core/rtnetlink.c:2728 rtnetlink_rcv_msg+0x3be/0xb10 net/core/rtnetlink.c:4316 netlink_rcv_skb+0x125/0x390 net/netlink/af_netlink.c:2433 netlink_unicast_kernel net/netlink/af_netlink.c:1287 [inline] netlink_unicast+0x437/0x610 net/netlink/af_netlink.c:1313 netlink_sendmsg+0x62e/0xb80 net/netlink/af_netlink.c:1878 sock_sendmsg_nosec net/socket.c:646 [inline] sock_sendmsg+0xb5/0x100 net/socket.c:656 sock_no_sendpage+0xe2/0x110 net/core/sock.c:2595 kernel_sendpage net/socket.c:3407 [inline] sock_sendpage+0xdf/0x140 net/socket.c:871 pipe_to_sendpage+0x226/0x2d0 fs/splice.c:451 splice_from_pipe_feed fs/splice.c:502 [inline] __splice_from_pipe+0x326/0x7a0 fs/splice.c:626 splice_from_pipe fs/splice.c:661 [inline] generic_splice_sendpage+0xc1/0x110 fs/splice.c:832 do_splice_from fs/splice.c:851 [inline] do_splice fs/splice.c:1147 [inline] SYSC_splice fs/splice.c:1402 [inline] SyS_splice+0xd59/0x1380 fs/splice.c:1382 do_syscall_64+0x1d5/0x640 arch/x86/entry/common.c:292 entry_SYSCALL_64_after_hwframe+0x46/0xbb Freed by task 6338: save_stack mm/kasan/kasan.c:447 [inline] set_track mm/kasan/kasan.c:459 [inline] kasan_slab_free+0xc3/0x1a0 mm/kasan/kasan.c:524 __cache_free mm/slab.c:3496 [inline] kfree+0xc9/0x250 mm/slab.c:3815 __rcu_reclaim kernel/rcu/rcu.h:195 [inline] rcu_do_batch kernel/rcu/tree.c:2699 [inline] invoke_rcu_callbacks kernel/rcu/tree.c:2962 [inline] __rcu_process_callbacks kernel/rcu/tree.c:2929 [inline] rcu_process_callbacks+0x780/0x1180 kernel/rcu/tree.c:2946 __do_softirq+0x254/0xa1d kernel/softirq.c:288 The buggy address belongs to the object at ffff8880469a9380 which belongs to the cache kmalloc-96 of size 96 The buggy address is located 0 bytes inside of 96-byte region [ffff8880469a9380, ffff8880469a93e0) The buggy address belongs to the page: page:ffffea00011a6a40 count:1 mapcount:0 mapping:ffff8880469a9000 index:0x0 flags: 0xfffe0000000100(slab) raw: 00fffe0000000100 ffff8880469a9000 0000000000000000 0000000100000020 raw: ffffea0002555d20 ffffea00027d6ee0 ffff88812fe504c0 0000000000000000 page dumped because: kasan: bad access detected Memory state around the buggy address: ffff8880469a9280: fb fb fb fb fb fb fb fb fb fb fb fb fc fc fc fc ffff8880469a9300: fb fb fb fb fb fb fb fb fb fb fb fb fc fc fc fc >ffff8880469a9380: fb fb fb fb fb fb fb fb fb fb fb fb fc fc fc fc ^ ffff8880469a9400: fb fb fb fb fb fb fb fb fb fb fb fb fc fc fc fc ffff8880469a9480: 00 00 00 00 00 00 00 00 00 fc fc fc fc fc fc fc ==================================================================