netlink: 'syz-executor0': attribute type 2 has an invalid length. ================================================================== BUG: KASAN: use-after-free in nla_strlcpy+0x13d/0x150 lib/nlattr.c:314 Read of size 1 at addr ffff8801cf4e7d9d by task syz-executor0/12742 CPU: 1 PID: 12742 Comm: syz-executor0 Not tainted 4.17.0-rc6+ #69 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:00007f50865c7c68 EFLAGS: 00000246 ORIG_RAX: 0000000000000001 RAX: ffffffffffffffda RBX: 00007f50865c86d4 RCX: 0000000000455a09 RDX: 000000000000001f RSI: 0000000020000040 RDI: 0000000000000014 RBP: 000000000072bea0 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 00000000ffffffff R13: 000000000000077b R14: 00000000006ff428 R15: 0000000000000000 Allocated by task 11028: 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 __do_kmalloc_node mm/slab.c:3682 [inline] __kmalloc_node_track_caller+0x47/0x70 mm/slab.c:3696 __kmalloc_reserve.isra.38+0x3a/0xe0 net/core/skbuff.c:137 __alloc_skb+0x14d/0x780 net/core/skbuff.c:205 alloc_skb include/linux/skbuff.h:987 [inline] netlink_alloc_large_skb net/netlink/af_netlink.c:1182 [inline] netlink_sendmsg+0xb01/0xfa0 net/netlink/af_netlink.c:1876 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 Freed by task 11028: 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] kfree+0xd9/0x260 mm/slab.c:3813 skb_free_head+0x99/0xc0 net/core/skbuff.c:550 skb_release_data+0x690/0x860 net/core/skbuff.c:570 skb_release_all+0x4a/0x60 net/core/skbuff.c:627 __kfree_skb net/core/skbuff.c:641 [inline] consume_skb+0x18b/0x550 net/core/skbuff.c:701 netlink_unicast_kernel net/netlink/af_netlink.c:1311 [inline] netlink_unicast+0x593/0x740 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 The buggy address belongs to the object at ffff8801cf4e7d00 which belongs to the cache kmalloc-512 of size 512 The buggy address is located 157 bytes inside of 512-byte region [ffff8801cf4e7d00, ffff8801cf4e7f00) The buggy address belongs to the page: page:ffffea00073d39c0 count:1 mapcount:0 mapping:ffff8801cf4e7080 index:0xffff8801cf4e7300 flags: 0x2fffc0000000100(slab) raw: 02fffc0000000100 ffff8801cf4e7080 ffff8801cf4e7300 0000000100000004 raw: ffffea0006f098e0 ffffea0006b76020 ffff8801da800940 0000000000000000 page dumped because: kasan: bad access detected Memory state around the buggy address: ffff8801cf4e7c80: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ffff8801cf4e7d00: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb >ffff8801cf4e7d80: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ^ ffff8801cf4e7e00: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff8801cf4e7e80: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ==================================================================