================================================================== BUG: KASAN: use-after-free in xfrm_policy_insert_list+0xd32/0xfb0 net/xfrm/xfrm_policy.c:1532 Read of size 1 at addr ffff8880a485efd9 by task syz-executor1/29737 CPU: 1 PID: 29737 Comm: syz-executor1 Not tainted 5.0.0-rc2+ #14 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_list+0xd32/0xfb0 net/xfrm/xfrm_policy.c:1532 xfrm_policy_inexact_insert+0x155/0xda0 net/xfrm/xfrm_policy.c:1195 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:00007f0098593c78 EFLAGS: 00000246 ORIG_RAX: 000000000000002e RAX: ffffffffffffffda RBX: 0000000000000003 RCX: 0000000000458099 RDX: 0000000000000000 RSI: 000000002014f000 RDI: 0000000000000003 RBP: 000000000073bf00 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 00007f00985946d4 R13: 00000000004c562b R14: 00000000004d9298 R15: 00000000ffffffff Allocated by task 28375: 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_fclone include/linux/skbuff.h:1053 [inline] tipc_buf_acquire+0x2f/0x100 net/tipc/msg.c:66 tipc_msg_create+0x38/0x270 net/tipc/msg.c:98 tipc_group_proto_xmit+0x376/0xb70 net/tipc/group.c:702 tipc_group_cong+0x4c4/0x5e0 net/tipc/group.c:438 tipc_group_bc_cong+0x2a6/0x3c0 net/tipc/group.c:459 tipc_send_group_bcast+0x465/0xdb0 net/tipc/socket.c:1031 __tipc_sendmsg+0xfc6/0x2080 net/tipc/socket.c:1322 tipc_sendmsg+0x53/0x80 net/tipc/socket.c:1287 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 28375: 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] kfree_skb net/core/skbuff.c:659 [inline] kfree_skb+0x199/0x580 net/core/skbuff.c:653 tipc_sk_proto_rcv net/tipc/socket.c:2002 [inline] tipc_sk_filter_rcv+0x21e4/0x3d50 net/tipc/socket.c:2155 tipc_sk_enqueue+0xb58/0x2130 net/tipc/socket.c:2244 tipc_sk_rcv+0x392/0x1040 net/tipc/socket.c:2295 tipc_node_xmit+0x2d8/0x750 net/tipc/node.c:1383 tipc_node_xmit_skb+0x171/0x260 net/tipc/node.c:1432 tipc_node_distr_xmit+0xd3/0x2b0 net/tipc/node.c:1447 tipc_group_cong+0x4f5/0x5e0 net/tipc/group.c:439 tipc_group_bc_cong+0x2a6/0x3c0 net/tipc/group.c:459 tipc_send_group_bcast+0x465/0xdb0 net/tipc/socket.c:1031 __tipc_sendmsg+0xfc6/0x2080 net/tipc/socket.c:1322 tipc_sendmsg+0x53/0x80 net/tipc/socket.c:1287 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 The buggy address belongs to the object at ffff8880a485edc0 which belongs to the cache kmalloc-1k of size 1024 The buggy address is located 537 bytes inside of 1024-byte region [ffff8880a485edc0, ffff8880a485f1c0) The buggy address belongs to the page: page:ffffea0002921780 count:1 mapcount:0 mapping:ffff88812c3f0ac0 index:0x0 compound_mapcount: 0 flags: 0x1fffc0000010200(slab|head) raw: 01fffc0000010200 ffffea0002373988 ffffea00025bad08 ffff88812c3f0ac0 raw: 0000000000000000 ffff8880a485e040 0000000100000007 0000000000000000 page dumped because: kasan: bad access detected Memory state around the buggy address: ffff8880a485ee80: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff8880a485ef00: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb >ffff8880a485ef80: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ^ ffff8880a485f000: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff8880a485f080: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ==================================================================