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BUG: KASAN: use-after-free in __list_del_entry_valid+0xe7/0xf3 lib/list_debug.c:54
Read of size 8 at addr ffff8880a27b96b8 by task syz-executor.3/8323

CPU: 0 PID: 8323 Comm: syz-executor.3 Not tainted 5.5.0-rc1-syzkaller #0
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+0x12d/0x187 lib/dump_stack.c:118
 print_address_description.constprop.8.cold.10+0x9/0x31d mm/kasan/report.c:374
 __kasan_report.cold.11+0x1b/0x3a mm/kasan/report.c:506
 kasan_report+0x12/0x20 mm/kasan/common.c:639
 __asan_report_load8_noabort+0x14/0x20 mm/kasan/generic_report.c:135
 __list_del_entry_valid+0xe7/0xf3 lib/list_debug.c:54
 __list_del_entry include/linux/list.h:131 [inline]
 list_del include/linux/list.h:139 [inline]
 root_remove_peer_lists+0x1c7/0x420 drivers/net/wireguard/allowedips.c:70
 wg_allowedips_free+0x1ba/0x2d0 drivers/net/wireguard/allowedips.c:305
 wg_peer_remove_all+0xc5/0x5f0 drivers/net/wireguard/peer.c:187
 wg_set_device+0xbde/0x1180 drivers/net/wireguard/netlink.c:542
 genl_family_rcv_msg_doit net/netlink/genetlink.c:672 [inline]
 genl_family_rcv_msg net/netlink/genetlink.c:717 [inline]
 genl_rcv_msg+0x5d9/0x10e0 net/netlink/genetlink.c:734
 netlink_rcv_skb+0x13c/0x380 net/netlink/af_netlink.c:2477
 genl_rcv+0x23/0x40 net/netlink/genetlink.c:745
 netlink_unicast_kernel net/netlink/af_netlink.c:1302 [inline]
 netlink_unicast+0x45e/0x6a0 net/netlink/af_netlink.c:1328
 netlink_sendmsg+0x7b0/0xcb0 net/netlink/af_netlink.c:1917
 sock_sendmsg_nosec net/socket.c:639 [inline]
 sock_sendmsg+0xb5/0xf0 net/socket.c:659
 ____sys_sendmsg+0x603/0x950 net/socket.c:2330
 ___sys_sendmsg+0xe4/0x160 net/socket.c:2384
 __sys_sendmsg+0xd9/0x180 net/socket.c:2417
 __do_sys_sendmsg net/socket.c:2426 [inline]
 __se_sys_sendmsg net/socket.c:2424 [inline]
 __x64_sys_sendmsg+0x73/0xb0 net/socket.c:2424
 do_syscall_64+0xca/0x5f0 arch/x86/entry/common.c:294
 entry_SYSCALL_64_after_hwframe+0x49/0xbe
RIP: 0033:0x45b399
Code: ad b6 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 7b b6 fb ff c3 66 2e 0f 1f 84 00 00 00 00
RSP: 002b:00007f9b1a002c78 EFLAGS: 00000246 ORIG_RAX: 000000000000002e
RAX: ffffffffffffffda RBX: 00007f9b1a0036d4 RCX: 000000000045b399
RDX: 0000000000000000 RSI: 0000000020001340 RDI: 0000000000000003
RBP: 000000000075bf20 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000004
R13: 00000000000009ba R14: 00000000004cb2b8 R15: 0000000000000009

Allocated by task 8320:
 save_stack+0x21/0x90 mm/kasan/common.c:72
 set_track mm/kasan/common.c:80 [inline]
 __kasan_kmalloc.constprop.17+0xc7/0xd0 mm/kasan/common.c:513
 kasan_kmalloc+0x9/0x10 mm/kasan/common.c:527
 kmem_cache_alloc_trace+0x15b/0x780 mm/slab.c:3551
 kmalloc include/linux/slab.h:556 [inline]
 kzalloc include/linux/slab.h:670 [inline]
 add+0x4e4/0x1810 drivers/net/wireguard/allowedips.c:241
 wg_allowedips_insert_v4+0xc7/0x170 drivers/net/wireguard/allowedips.c:325
 set_allowedip drivers/net/wireguard/netlink.c:343 [inline]
 set_peer+0xd09/0x10e0 drivers/net/wireguard/netlink.c:468
 wg_set_device+0x876/0x1180 drivers/net/wireguard/netlink.c:591
 genl_family_rcv_msg_doit net/netlink/genetlink.c:672 [inline]
 genl_family_rcv_msg net/netlink/genetlink.c:717 [inline]
 genl_rcv_msg+0x5d9/0x10e0 net/netlink/genetlink.c:734
 netlink_rcv_skb+0x13c/0x380 net/netlink/af_netlink.c:2477
 genl_rcv+0x23/0x40 net/netlink/genetlink.c:745
 netlink_unicast_kernel net/netlink/af_netlink.c:1302 [inline]
 netlink_unicast+0x45e/0x6a0 net/netlink/af_netlink.c:1328
 netlink_sendmsg+0x7b0/0xcb0 net/netlink/af_netlink.c:1917
 sock_sendmsg_nosec net/socket.c:639 [inline]
 sock_sendmsg+0xb5/0xf0 net/socket.c:659
 ____sys_sendmsg+0x603/0x950 net/socket.c:2330
 ___sys_sendmsg+0xe4/0x160 net/socket.c:2384
 __sys_sendmsg+0xd9/0x180 net/socket.c:2417
 __do_sys_sendmsg net/socket.c:2426 [inline]
 __se_sys_sendmsg net/socket.c:2424 [inline]
 __x64_sys_sendmsg+0x73/0xb0 net/socket.c:2424
 do_syscall_64+0xca/0x5f0 arch/x86/entry/common.c:294
 entry_SYSCALL_64_after_hwframe+0x49/0xbe

Freed by task 8320:
 save_stack+0x21/0x90 mm/kasan/common.c:72
 set_track mm/kasan/common.c:80 [inline]
 kasan_set_free_info mm/kasan/common.c:335 [inline]
 __kasan_slab_free+0x102/0x150 mm/kasan/common.c:474
 kasan_slab_free+0xe/0x10 mm/kasan/common.c:483
 __cache_free mm/slab.c:3426 [inline]
 kfree+0x108/0x2c0 mm/slab.c:3757
 add+0xf90/0x1810 drivers/net/wireguard/allowedips.c:271
 wg_allowedips_insert_v4+0xc7/0x170 drivers/net/wireguard/allowedips.c:325
 set_allowedip drivers/net/wireguard/netlink.c:343 [inline]
 set_peer+0xd09/0x10e0 drivers/net/wireguard/netlink.c:468
 wg_set_device+0x876/0x1180 drivers/net/wireguard/netlink.c:591
 genl_family_rcv_msg_doit net/netlink/genetlink.c:672 [inline]
 genl_family_rcv_msg net/netlink/genetlink.c:717 [inline]
 genl_rcv_msg+0x5d9/0x10e0 net/netlink/genetlink.c:734
 netlink_rcv_skb+0x13c/0x380 net/netlink/af_netlink.c:2477
 genl_rcv+0x23/0x40 net/netlink/genetlink.c:745
 netlink_unicast_kernel net/netlink/af_netlink.c:1302 [inline]
 netlink_unicast+0x45e/0x6a0 net/netlink/af_netlink.c:1328
 netlink_sendmsg+0x7b0/0xcb0 net/netlink/af_netlink.c:1917
 sock_sendmsg_nosec net/socket.c:639 [inline]
 sock_sendmsg+0xb5/0xf0 net/socket.c:659
 ____sys_sendmsg+0x603/0x950 net/socket.c:2330
 ___sys_sendmsg+0xe4/0x160 net/socket.c:2384
 __sys_sendmsg+0xd9/0x180 net/socket.c:2417
 __do_sys_sendmsg net/socket.c:2426 [inline]
 __se_sys_sendmsg net/socket.c:2424 [inline]
 __x64_sys_sendmsg+0x73/0xb0 net/socket.c:2424
 do_syscall_64+0xca/0x5f0 arch/x86/entry/common.c:294
 entry_SYSCALL_64_after_hwframe+0x49/0xbe

The buggy address belongs to the object at ffff8880a27b9680
 which belongs to the cache kmalloc-64 of size 64
The buggy address is located 56 bytes inside of
 64-byte region [ffff8880a27b9680, ffff8880a27b96c0)
The buggy address belongs to the page:
page:ffffea000289ee40 refcount:1 mapcount:0 mapping:ffff8880aa400380 index:0x0
raw: 00fffe0000000200 ffffea00028b8948 ffffea00028ae5c8 ffff8880aa400380
raw: 0000000000000000 ffff8880a27b9000 0000000100000020 0000000000000000
page dumped because: kasan: bad access detected

Memory state around the buggy address:
 ffff8880a27b9580: fb fb fb fb fb fb fb fb fc fc fc fc fc fc fc fc
 ffff8880a27b9600: 00 00 00 00 00 00 00 00 fc fc fc fc fc fc fc fc
>ffff8880a27b9680: fb fb fb fb fb fb fb fb fc fc fc fc fc fc fc fc
                                        ^
 ffff8880a27b9700: 00 00 00 00 00 00 00 00 fc fc fc fc fc fc fc fc
 ffff8880a27b9780: fb fb fb fb fb fb fb fb fc fc fc fc fc fc fc fc
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