================================================================== BUG: KASAN: use-after-free in nla_strlcpy+0x13d/0x150 lib/nlattr.c:314 Read of size 1 at addr ffff8801be2d32ad by task syz-executor0/19073 CPU: 1 PID: 19073 Comm: syz-executor0 Not tainted 4.17.0-rc7+ #78 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+0x1b9/0x294 lib/dump_stack.c:113 print_address_description+0x6c/0x20b mm/kasan/report.c:256 kasan_report_error mm/kasan/report.c:354 [inline] kasan_report.cold.7+0x242/0x2fe mm/kasan/report.c:412 __asan_report_load1_noabort+0x14/0x20 mm/kasan/report.c:430 nla_strlcpy+0x13d/0x150 lib/nlattr.c:314 nfnl_acct_new+0x574/0xc50 net/netfilter/nfnetlink_acct.c:118 nfnetlink_rcv_msg+0xdb5/0xff0 net/netfilter/nfnetlink.c:212 netlink_rcv_skb+0x172/0x440 net/netlink/af_netlink.c:2448 nfnetlink_rcv+0x1fe/0x1ba0 net/netfilter/nfnetlink.c:513 netlink_unicast_kernel net/netlink/af_netlink.c:1310 [inline] netlink_unicast+0x58b/0x740 net/netlink/af_netlink.c:1336 netlink_sendmsg+0x9f0/0xfa0 net/netlink/af_netlink.c:1901 sock_sendmsg_nosec net/socket.c:629 [inline] sock_sendmsg+0xd5/0x120 net/socket.c:639 sock_write_iter+0x35a/0x5a0 net/socket.c:908 call_write_iter include/linux/fs.h:1784 [inline] new_sync_write fs/read_write.c:474 [inline] __vfs_write+0x64d/0x960 fs/read_write.c:487 vfs_write+0x1f8/0x560 fs/read_write.c:549 ksys_write+0xf9/0x250 fs/read_write.c:598 __do_sys_write fs/read_write.c:610 [inline] __se_sys_write fs/read_write.c:607 [inline] __x64_sys_write+0x73/0xb0 fs/read_write.c:607 do_syscall_64+0x1b1/0x800 arch/x86/entry/common.c:287 entry_SYSCALL_64_after_hwframe+0x49/0xbe RIP: 0033:0x455a09 RSP: 002b:00007f2e7e03bc68 EFLAGS: 00000246 ORIG_RAX: 0000000000000001 RAX: ffffffffffffffda RBX: 00007f2e7e03c6d4 RCX: 0000000000455a09 RDX: 000000000000001f RSI: 0000000020000080 RDI: 0000000000000013 RBP: 000000000072bea0 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 00000000ffffffff R13: 00000000000007a8 R14: 0000000000700860 R15: 0000000000000000 Allocated by task 17644: save_stack+0x43/0xd0 mm/kasan/kasan.c:448 set_track mm/kasan/kasan.c:460 [inline] kasan_kmalloc+0xc4/0xe0 mm/kasan/kasan.c:553 kasan_slab_alloc+0x12/0x20 mm/kasan/kasan.c:490 kmem_cache_alloc+0x12e/0x760 mm/slab.c:3554 kmem_cache_zalloc include/linux/slab.h:691 [inline] sctp_chunkify+0xce/0x400 net/sctp/sm_make_chunk.c:1355 _sctp_make_chunk+0x157/0x280 net/sctp/sm_make_chunk.c:1428 sctp_make_data net/sctp/sm_make_chunk.c:1449 [inline] sctp_make_datafrag_empty+0x1ce/0x2d0 net/sctp/sm_make_chunk.c:768 sctp_datamsg_from_user+0x922/0x1540 net/sctp/chunk.c:283 sctp_sendmsg_to_asoc+0xd08/0x2100 net/sctp/socket.c:1950 sctp_sendmsg+0x13a8/0x1d70 net/sctp/socket.c:2122 inet_sendmsg+0x19f/0x690 net/ipv4/af_inet.c:798 sock_sendmsg_nosec net/socket.c:629 [inline] sock_sendmsg+0xd5/0x120 net/socket.c:639 __sys_sendto+0x3d7/0x670 net/socket.c:1789 __do_sys_sendto net/socket.c:1801 [inline] __se_sys_sendto net/socket.c:1797 [inline] __x64_sys_sendto+0xe1/0x1a0 net/socket.c:1797 do_syscall_64+0x1b1/0x800 arch/x86/entry/common.c:287 entry_SYSCALL_64_after_hwframe+0x49/0xbe Freed by task 17644: save_stack+0x43/0xd0 mm/kasan/kasan.c:448 set_track mm/kasan/kasan.c:460 [inline] __kasan_slab_free+0x11a/0x170 mm/kasan/kasan.c:521 kasan_slab_free+0xe/0x10 mm/kasan/kasan.c:528 __cache_free mm/slab.c:3498 [inline] kmem_cache_free+0x86/0x2d0 mm/slab.c:3756 sctp_chunk_destroy net/sctp/sm_make_chunk.c:1481 [inline] sctp_chunk_put+0x321/0x440 net/sctp/sm_make_chunk.c:1504 sctp_chunk_free+0x53/0x60 net/sctp/sm_make_chunk.c:1491 __sctp_outq_teardown+0xa9e/0x1290 net/sctp/outqueue.c:271 sctp_outq_free+0x15/0x20 net/sctp/outqueue.c:291 sctp_association_free+0x2e8/0x959 net/sctp/associola.c:356 sctp_cmd_delete_tcb net/sctp/sm_sideeffect.c:939 [inline] sctp_cmd_interpreter net/sctp/sm_sideeffect.c:1353 [inline] sctp_side_effects net/sctp/sm_sideeffect.c:1220 [inline] sctp_do_sm+0x49de/0x7160 net/sctp/sm_sideeffect.c:1191 sctp_assoc_bh_rcv+0x346/0x670 net/sctp/associola.c:1090 sctp_inq_push+0x263/0x320 net/sctp/inqueue.c:95 sctp_backlog_rcv+0x192/0xc00 net/sctp/input.c:350 sk_backlog_rcv include/net/sock.h:909 [inline] __release_sock+0x12f/0x3a0 net/core/sock.c:2335 release_sock+0xa4/0x2b0 net/core/sock.c:2850 sctp_sendmsg+0x13cc/0x1d70 net/sctp/socket.c:2127 inet_sendmsg+0x19f/0x690 net/ipv4/af_inet.c:798 sock_sendmsg_nosec net/socket.c:629 [inline] sock_sendmsg+0xd5/0x120 net/socket.c:639 __sys_sendto+0x3d7/0x670 net/socket.c:1789 __do_sys_sendto net/socket.c:1801 [inline] __se_sys_sendto net/socket.c:1797 [inline] __x64_sys_sendto+0xe1/0x1a0 net/socket.c:1797 do_syscall_64+0x1b1/0x800 arch/x86/entry/common.c:287 entry_SYSCALL_64_after_hwframe+0x49/0xbe The buggy address belongs to the object at ffff8801be2d31c0 which belongs to the cache sctp_chunk of size 256 The buggy address is located 237 bytes inside of 256-byte region [ffff8801be2d31c0, ffff8801be2d32c0) The buggy address belongs to the page: page:ffffea0006f8b4c0 count:1 mapcount:0 mapping:ffff8801be2d3080 index:0x0 flags: 0x2fffc0000000100(slab) raw: 02fffc0000000100 ffff8801be2d3080 0000000000000000 000000010000000c raw: ffffea0007119560 ffffea00072e5b60 ffff8801cd41da80 0000000000000000 page dumped because: kasan: bad access detected Memory state around the buggy address: ffff8801be2d3180: fc fc fc fc fc fc fc fc fb fb fb fb fb fb fb fb ffff8801be2d3200: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb >ffff8801be2d3280: fb fb fb fb fb fb fb fb fc fc fc fc fc fc fc fc ^ ffff8801be2d3300: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff8801be2d3380: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ==================================================================