================================================================== BUG: KASAN: slab-out-of-bounds in erspan_xmit+0x22d4/0x2430 net/ipv4/ip_gre.c:735 Read of size 2 at addr ffff8801aef525cb by task syz-executor5/21707 CPU: 1 PID: 21707 Comm: syz-executor5 Not tainted 4.15.0-rc9+ #206 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 sctp: [Deprecated]: syz-executor7 (pid 21727) Use of struct sctp_assoc_value in delayed_ack socket option. Use struct sctp_sack_info instead Call Trace: __dump_stack lib/dump_stack.c:17 [inline] dump_stack+0x194/0x257 lib/dump_stack.c:53 print_address_description+0x73/0x250 mm/kasan/report.c:252 kasan_report_error mm/kasan/report.c:351 [inline] kasan_report+0x25b/0x340 mm/kasan/report.c:409 __asan_report_load_n_noabort+0xf/0x20 mm/kasan/report.c:440 erspan_xmit+0x22d4/0x2430 net/ipv4/ip_gre.c:735 __netdev_start_xmit include/linux/netdevice.h:4055 [inline] netdev_start_xmit include/linux/netdevice.h:4064 [inline] packet_direct_xmit+0x3ad/0x790 net/packet/af_packet.c:267 packet_snd net/packet/af_packet.c:2944 [inline] packet_sendmsg+0x3aed/0x60b0 net/packet/af_packet.c:2969 sctp: [Deprecated]: syz-executor7 (pid 21740) Use of struct sctp_assoc_value in delayed_ack socket option. Use struct sctp_sack_info instead sock_sendmsg_nosec net/socket.c:630 [inline] sock_sendmsg+0xca/0x110 net/socket.c:640 SYSC_sendto+0x361/0x5c0 net/socket.c:1721 SyS_sendto+0x40/0x50 net/socket.c:1689 entry_SYSCALL_64_fastpath+0x29/0xa0 RIP: 0033:0x452f19 RSP: 002b:00007f48fe030c58 EFLAGS: 00000212 ORIG_RAX: 000000000000002c RAX: ffffffffffffffda RBX: 000000000071bea0 RCX: 0000000000452f19 RDX: 0000000000000000 RSI: 0000000020003fd9 RDI: 0000000000000013 RBP: 00000000000003d6 R08: 0000000020009fe4 R09: 000000000000001c R10: 0000000000000000 R11: 0000000000000212 R12: 00000000006f4cb0 R13: 00000000ffffffff R14: 00007f48fe0316d4 R15: 0000000000000000 Allocated by task 3721: save_stack+0x43/0xd0 mm/kasan/kasan.c:447 set_track mm/kasan/kasan.c:459 [inline] kasan_kmalloc+0xad/0xe0 mm/kasan/kasan.c:551 kmem_cache_alloc_trace+0x136/0x750 mm/slab.c:3610 kmalloc include/linux/slab.h:499 [inline] kzalloc include/linux/slab.h:688 [inline] ipmr_new_table.part.42+0x23f/0x650 net/ipv4/ipmr.c:368 ipmr_new_table include/linux/list.h:29 [inline] ipmr_rules_init net/ipv4/ipmr.c:236 [inline] ipmr_net_init+0x18c/0x450 net/ipv4/ipmr.c:3292 ops_init+0x10a/0x570 net/core/net_namespace.c:118 setup_net+0x313/0x710 net/core/net_namespace.c:302 copy_net_ns+0x238/0x580 net/core/net_namespace.c:426 create_new_namespaces+0x425/0x880 kernel/nsproxy.c:107 unshare_nsproxy_namespaces+0xae/0x1e0 kernel/nsproxy.c:206 SYSC_unshare kernel/fork.c:2365 [inline] SyS_unshare+0x653/0xfa0 kernel/fork.c:2315 entry_SYSCALL_64_fastpath+0x29/0xa0 Freed by task 0: (stack is not available) The buggy address belongs to the object at ffff8801aef526c0 which belongs to the cache kmalloc-4096 of size 4096 The buggy address is located 245 bytes to the left of 4096-byte region [ffff8801aef526c0, ffff8801aef536c0) The buggy address belongs to the page: page:ffffea0006bbd480 count:1 mapcount:0 mapping:ffff8801aef526c0 index:0x0 compound_mapcount: 0 flags: 0x2fffc0000008100(slab|head) raw: 02fffc0000008100 ffff8801aef526c0 0000000000000000 0000000100000001 raw: ffffea0006bbba20 ffffea0006bbd520 ffff8801dac00dc0 0000000000000000 page dumped because: kasan: bad access detected Memory state around the buggy address: ffff8801aef52480: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ffff8801aef52500: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc >ffff8801aef52580: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ^ ffff8801aef52600: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ffff8801aef52680: fc fc fc fc fc fc fc fc 00 00 00 00 00 00 00 00 ==================================================================