================================================================== BUG: KASAN: use-after-free in xfrm_sk_policy_lookup+0x319/0x490 net/xfrm/xfrm_policy.c:2167 Read of size 2 at addr ffff88809264cf9e by task syz-executor.2/20406 CPU: 0 PID: 20406 Comm: syz-executor.2 Not tainted 5.2.0-rc7 #12 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+0x1d8/0x2f8 lib/dump_stack.c:113 print_address_description+0x6d/0x310 mm/kasan/report.c:188 __kasan_report+0x14b/0x1c0 mm/kasan/report.c:317 kasan_report+0x26/0x50 mm/kasan/common.c:614 __asan_report_load2_noabort+0x14/0x20 mm/kasan/generic_report.c:130 xfrm_sk_policy_lookup+0x319/0x490 net/xfrm/xfrm_policy.c:2167 xfrm_lookup_with_ifid+0x219/0x2470 net/xfrm/xfrm_policy.c:3036 xfrm_lookup net/xfrm/xfrm_policy.c:3173 [inline] xfrm_lookup_route+0x3b/0x190 net/xfrm/xfrm_policy.c:3184 ip6_dst_lookup_flow+0x168/0x1a0 net/ipv6/ip6_output.c:1096 inet6_csk_route_socket+0x581/0xb80 net/ipv6/inet6_connection_sock.c:106 inet6_csk_xmit+0xf3/0x470 net/ipv6/inet6_connection_sock.c:121 l2tp_xmit_core net/l2tp/l2tp_core.c:1030 [inline] l2tp_xmit_skb+0xb71/0x10a0 net/l2tp/l2tp_core.c:1132 pppol2tp_sendmsg+0x3f8/0x650 net/l2tp/l2tp_ppp.c:325 sock_sendmsg_nosec net/socket.c:646 [inline] sock_sendmsg net/socket.c:665 [inline] ___sys_sendmsg+0x66b/0x9a0 net/socket.c:2286 __sys_sendmmsg+0x2ac/0x520 net/socket.c:2381 __do_sys_sendmmsg net/socket.c:2410 [inline] __se_sys_sendmmsg net/socket.c:2407 [inline] __x64_sys_sendmmsg+0xa0/0xb0 net/socket.c:2407 do_syscall_64+0xfe/0x140 arch/x86/entry/common.c:301 entry_SYSCALL_64_after_hwframe+0x49/0xbe RIP: 0033:0x459519 Code: fd 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 cb b7 fb ff c3 66 2e 0f 1f 84 00 00 00 00 RSP: 002b:00007fd2a1719c78 EFLAGS: 00000246 ORIG_RAX: 0000000000000133 RAX: ffffffffffffffda RBX: 0000000000000004 RCX: 0000000000459519 RDX: 0800000000000059 RSI: 0000000020005fc0 RDI: 0000000000000007 RBP: 000000000075bf20 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 00007fd2a171a6d4 R13: 00000000004c6af9 R14: 00000000004dbd80 R15: 00000000ffffffff Allocated by task 20406: save_stack mm/kasan/common.c:71 [inline] set_track mm/kasan/common.c:79 [inline] __kasan_kmalloc+0x11c/0x1b0 mm/kasan/common.c:489 kasan_kmalloc+0x9/0x10 mm/kasan/common.c:503 kmem_cache_alloc_trace+0x209/0x2c0 mm/slab.c:3555 kmalloc include/linux/slab.h:547 [inline] kzalloc include/linux/slab.h:742 [inline] xfrm_policy_alloc+0x7e/0x2a0 net/xfrm/xfrm_policy.c:388 xfrm_compile_policy+0x83b/0x13d0 net/xfrm/xfrm_user.c:3001 xfrm_user_policy+0x450/0x820 net/xfrm/xfrm_state.c:2079 do_ipv6_setsockopt+0xf38/0x3bc0 net/ipv6/ipv6_sockglue.c:832 ipv6_setsockopt+0x51/0x170 net/ipv6/ipv6_sockglue.c:944 udpv6_setsockopt+0x7b/0x90 net/ipv6/udp.c:1571 sock_common_setsockopt+0x99/0xb0 net/core/sock.c:3126 __sys_setsockopt+0x1e2/0x250 net/socket.c:2072 __do_sys_setsockopt net/socket.c:2083 [inline] __se_sys_setsockopt net/socket.c:2080 [inline] __x64_sys_setsockopt+0xbf/0xd0 net/socket.c:2080 do_syscall_64+0xfe/0x140 arch/x86/entry/common.c:301 entry_SYSCALL_64_after_hwframe+0x49/0xbe Freed by task 20432: save_stack mm/kasan/common.c:71 [inline] set_track mm/kasan/common.c:79 [inline] __kasan_slab_free+0x12a/0x1e0 mm/kasan/common.c:451 kasan_slab_free+0xe/0x10 mm/kasan/common.c:459 __cache_free mm/slab.c:3432 [inline] kfree+0xae/0x120 mm/slab.c:3755 xfrm_policy_destroy_rcu+0x50/0x60 net/xfrm/xfrm_policy.c:412 __rcu_reclaim kernel/rcu/rcu.h:222 [inline] rcu_do_batch kernel/rcu/tree.c:2092 [inline] invoke_rcu_callbacks kernel/rcu/tree.c:2310 [inline] rcu_core+0x8d6/0xf90 kernel/rcu/tree.c:2291 __do_softirq+0x340/0x7b0 arch/x86/include/asm/paravirt.h:777 The buggy address belongs to the object at ffff88809264cd80 which belongs to the cache kmalloc-1k of size 1024 The buggy address is located 542 bytes inside of 1024-byte region [ffff88809264cd80, ffff88809264d180) The buggy address belongs to the page: page:ffffea0002499300 refcount:1 mapcount:0 mapping:ffff8880aa400ac0 index:0x0 compound_mapcount: 0 flags: 0x1fffc0000010200(slab|head) raw: 01fffc0000010200 ffffea0002787c08 ffffea00022f4308 ffff8880aa400ac0 raw: 0000000000000000 ffff88809264c000 0000000100000007 0000000000000000 page dumped because: kasan: bad access detected Memory state around the buggy address: ffff88809264ce80: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff88809264cf00: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb >ffff88809264cf80: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ^ ffff88809264d000: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff88809264d080: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ==================================================================