================================================================== BUG: KASAN: use-after-free in __xfrm_policy_eval_candidates net/xfrm/xfrm_policy.c:2019 [inline] BUG: KASAN: use-after-free in xfrm_policy_eval_candidates net/xfrm/xfrm_policy.c:2053 [inline] BUG: KASAN: use-after-free in xfrm_policy_lookup_bytype+0xd27/0xdb0 net/xfrm/xfrm_policy.c:2113 Read of size 4 at addr ffff888091c90534 by task syz-executor2/10355 CPU: 0 PID: 10355 Comm: syz-executor2 Not tainted 4.20.0+ #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_load4_noabort+0x14/0x20 mm/kasan/generic_report.c:134 __xfrm_policy_eval_candidates net/xfrm/xfrm_policy.c:2019 [inline] xfrm_policy_eval_candidates net/xfrm/xfrm_policy.c:2053 [inline] xfrm_policy_lookup_bytype+0xd27/0xdb0 net/xfrm/xfrm_policy.c:2113 xfrm_policy_lookup+0x7e/0x90 net/xfrm/xfrm_policy.c:2145 __xfrm_policy_check+0x1426/0x2b00 net/xfrm/xfrm_policy.c:3354 __xfrm_policy_check2 include/net/xfrm.h:1166 [inline] xfrm_policy_check include/net/xfrm.h:1175 [inline] xfrm6_policy_check include/net/xfrm.h:1185 [inline] udpv6_queue_rcv_one_skb+0x532/0x1750 net/ipv6/udp.c:615 udpv6_queue_rcv_skb+0x128/0x730 net/ipv6/udp.c:699 __udp6_lib_mcast_deliver net/ipv6/udp.c:812 [inline] __udp6_lib_rcv+0x1e8d/0x30d0 net/ipv6/udp.c:916 udpv6_rcv+0x22/0x30 net/ipv6/udp.c:1026 ip6_protocol_deliver_rcu+0x3aa/0x1940 net/ipv6/ip6_input.c:394 ip6_input_finish+0x84/0x170 net/ipv6/ip6_input.c:434 NF_HOOK include/linux/netfilter.h:289 [inline] NF_HOOK include/linux/netfilter.h:283 [inline] ip6_input+0xf9/0x600 net/ipv6/ip6_input.c:443 ip6_mc_input+0x4f9/0x10d0 net/ipv6/ip6_input.c:537 dst_input include/net/dst.h:450 [inline] ip6_rcv_finish+0x177/0x330 net/ipv6/ip6_input.c:76 NF_HOOK include/linux/netfilter.h:289 [inline] NF_HOOK include/linux/netfilter.h:283 [inline] ipv6_rcv+0x113/0x650 net/ipv6/ip6_input.c:272 __netif_receive_skb_one_core+0x160/0x210 net/core/dev.c:4973 __netif_receive_skb+0x2c/0x1c0 net/core/dev.c:5083 process_backlog+0x206/0x750 net/core/dev.c:5923 napi_poll net/core/dev.c:6346 [inline] net_rx_action+0x76d/0x1930 net/core/dev.c:6412 __do_softirq+0x30b/0xb11 kernel/softirq.c:292 do_softirq_own_stack+0x2a/0x40 arch/x86/entry/entry_64.S:1027 do_softirq.part.0+0x11a/0x170 kernel/softirq.c:337 do_softirq+0x18/0x20 kernel/softirq.c:325 netif_rx_ni+0x4fd/0x860 net/core/dev.c:4569 dev_loopback_xmit+0x29b/0x8c0 net/core/dev.c:3576 NF_HOOK include/linux/netfilter.h:289 [inline] NF_HOOK include/linux/netfilter.h:283 [inline] ip6_finish_output2+0x1a03/0x28e0 net/ipv6/ip6_output.c:84 ip6_finish_output+0x577/0xc30 net/ipv6/ip6_output.c:154 NF_HOOK_COND include/linux/netfilter.h:278 [inline] ip6_output+0x23c/0xa00 net/ipv6/ip6_output.c:171 dst_output include/net/dst.h:444 [inline] ip6_local_out+0xc4/0x1b0 net/ipv6/output_core.c:176 ip6_send_skb+0xbb/0x350 net/ipv6/ip6_output.c:1727 udp_v6_send_skb.isra.0+0x834/0x14b0 net/ipv6/udp.c:1169 udpv6_sendmsg+0x2ba8/0x3570 net/ipv6/udp.c:1466 inet_sendmsg+0x1af/0x740 net/ipv4/af_inet.c:798 sock_sendmsg_nosec net/socket.c:621 [inline] sock_sendmsg+0xdd/0x130 net/socket.c:631 __sys_sendto+0x387/0x5f0 net/socket.c:1788 __do_sys_sendto net/socket.c:1800 [inline] __se_sys_sendto net/socket.c:1796 [inline] __x64_sys_sendto+0xe1/0x1a0 net/socket.c:1796 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:00007f6a954c9c78 EFLAGS: 00000246 ORIG_RAX: 000000000000002c RAX: ffffffffffffffda RBX: 0000000000000006 RCX: 0000000000457ec9 RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000003 RBP: 000000000073bfa0 R08: 0000000020000300 R09: 000000000000001c R10: 0000000000000000 R11: 0000000000000246 R12: 00007f6a954ca6d4 R13: 00000000004c53f5 R14: 00000000004d8ef0 R15: 00000000ffffffff Allocated by task 7950: save_stack+0x45/0xd0 mm/kasan/common.c:73 set_track mm/kasan/common.c:85 [inline] kasan_kmalloc mm/kasan/common.c:482 [inline] kasan_kmalloc+0xcf/0xe0 mm/kasan/common.c:455 kmem_cache_alloc_trace+0x151/0x760 mm/slab.c:3607 kmalloc include/linux/slab.h:545 [inline] syslog_print kernel/printk/printk.c:1302 [inline] do_syslog kernel/printk/printk.c:1475 [inline] do_syslog+0x5aa/0x17c0 kernel/printk/printk.c:1449 kmsg_read+0x8f/0xc0 fs/proc/kmsg.c:40 proc_reg_read+0x29a/0x3c0 fs/proc/inode.c:231 __vfs_read+0x116/0xb20 fs/read_write.c:416 vfs_read+0x194/0x3e0 fs/read_write.c:452 ksys_read+0x105/0x260 fs/read_write.c:578 __do_sys_read fs/read_write.c:588 [inline] __se_sys_read fs/read_write.c:586 [inline] __x64_sys_read+0x73/0xb0 fs/read_write.c:586 do_syscall_64+0x1a3/0x800 arch/x86/entry/common.c:290 entry_SYSCALL_64_after_hwframe+0x49/0xbe Freed by task 7950: 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:444 kasan_slab_free+0xe/0x10 mm/kasan/common.c:452 __cache_free mm/slab.c:3485 [inline] kfree+0xcf/0x230 mm/slab.c:3804 syslog_print kernel/printk/printk.c:1361 [inline] do_syslog kernel/printk/printk.c:1475 [inline] do_syslog+0x8c8/0x17c0 kernel/printk/printk.c:1449 kmsg_read+0x8f/0xc0 fs/proc/kmsg.c:40 proc_reg_read+0x29a/0x3c0 fs/proc/inode.c:231 __vfs_read+0x116/0xb20 fs/read_write.c:416 vfs_read+0x194/0x3e0 fs/read_write.c:452 ksys_read+0x105/0x260 fs/read_write.c:578 __do_sys_read fs/read_write.c:588 [inline] __se_sys_read fs/read_write.c:586 [inline] __x64_sys_read+0x73/0xb0 fs/read_write.c:586 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 ffff888091c90480 which belongs to the cache kmalloc-1k of size 1024 The buggy address is located 180 bytes inside of 1024-byte region [ffff888091c90480, ffff888091c90880) The buggy address belongs to the page: page:ffffea0002472400 count:1 mapcount:0 mapping:ffff88812c3f0ac0 index:0x0 compound_mapcount: 0 flags: 0x1fffc0000010200(slab|head) raw: 01fffc0000010200 ffffea0001957508 ffffea0002600a88 ffff88812c3f0ac0 raw: 0000000000000000 ffff888091c90000 0000000100000007 0000000000000000 page dumped because: kasan: bad access detected Memory state around the buggy address: ffff888091c90400: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ffff888091c90480: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb >ffff888091c90500: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ^ ffff888091c90580: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff888091c90600: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb 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