netlink: 'syz-executor.4': attribute type 6 has an invalid length. ================================================================== BUG: KASAN: use-after-free in nla_memcpy+0x8b/0xa0 lib/nlattr.c:572 Read of size 2 at addr ffff888098f43514 by task syz-executor.4/7492 CPU: 1 PID: 7492 Comm: syz-executor.4 Not tainted 5.4.0-rc1+ #0 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+0x113/0x167 lib/dump_stack.c:113 print_address_description.constprop.8.cold.10+0x9/0x31d mm/kasan/report.c:374 __kasan_report.cold.11+0x1b/0x3a mm/kasan/report.c:506 kasan_report+0x12/0x20 mm/kasan/common.c:634 __asan_report_load2_noabort+0x14/0x20 mm/kasan/generic_report.c:130 nla_memcpy+0x8b/0xa0 lib/nlattr.c:572 nla_get_u64 include/net/netlink.h:1539 [inline] __cfg802154_wpan_dev_from_attrs+0x18a/0x750 net/ieee802154/nl802154.c:55 nl802154_prepare_wpan_dev_dump.isra.9.constprop.26+0xdf/0x4c0 net/ieee802154/nl802154.c:245 nl802154_dump_llsec_seclevel+0xd1/0xa60 net/ieee802154/nl802154.c:1985 genl_lock_dumpit+0x84/0xb0 net/netlink/genetlink.c:529 netlink_dump+0x49e/0x10c0 net/netlink/af_netlink.c:2244 __netlink_dump_start+0x52b/0x810 net/netlink/af_netlink.c:2352 genl_family_rcv_msg_dumpit net/netlink/genetlink.c:614 [inline] genl_family_rcv_msg net/netlink/genetlink.c:710 [inline] genl_rcv_msg+0xbbb/0x1280 net/netlink/genetlink.c:730 netlink_rcv_skb+0x13c/0x380 net/netlink/af_netlink.c:2477 genl_rcv+0x23/0x40 net/netlink/genetlink.c:741 netlink_unicast_kernel net/netlink/af_netlink.c:1302 [inline] netlink_unicast+0x43f/0x630 net/netlink/af_netlink.c:1328 netlink_sendmsg+0x75d/0xc40 net/netlink/af_netlink.c:1917 sock_sendmsg_nosec net/socket.c:637 [inline] sock_sendmsg+0xb5/0xf0 net/socket.c:657 ___sys_sendmsg+0x647/0x950 net/socket.c:2311 __sys_sendmsg+0xd9/0x180 net/socket.c:2356 __do_sys_sendmsg net/socket.c:2365 [inline] __se_sys_sendmsg net/socket.c:2363 [inline] __x64_sys_sendmsg+0x73/0xb0 net/socket.c:2363 do_syscall_64+0xca/0x5d0 arch/x86/entry/common.c:290 entry_SYSCALL_64_after_hwframe+0x49/0xbe RIP: 0033:0x459a59 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:00007fc66bdd4c78 EFLAGS: 00000246 ORIG_RAX: 000000000000002e RAX: ffffffffffffffda RBX: 0000000000000003 RCX: 0000000000459a59 RDX: 0000000000000000 RSI: 0000000020000000 RDI: 0000000000000003 RBP: 000000000075bf20 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 00007fc66bdd56d4 R13: 00000000004c7bad R14: 00000000004dd938 R15: 00000000ffffffff Allocated by task 7494: save_stack+0x21/0x90 mm/kasan/common.c:69 set_track mm/kasan/common.c:77 [inline] __kasan_kmalloc.constprop.9+0xc7/0xd0 mm/kasan/common.c:510 kasan_kmalloc+0x9/0x10 mm/kasan/common.c:524 __do_kmalloc_node mm/slab.c:3615 [inline] __kmalloc_node_track_caller+0x4d/0x70 mm/slab.c:3629 __kmalloc_reserve.isra.46+0x2c/0xc0 net/core/skbuff.c:141 __alloc_skb+0xd7/0x570 net/core/skbuff.c:209 alloc_skb include/linux/skbuff.h:1049 [inline] netlink_alloc_large_skb net/netlink/af_netlink.c:1174 [inline] netlink_sendmsg+0x808/0xc40 net/netlink/af_netlink.c:1892 sock_sendmsg_nosec net/socket.c:637 [inline] sock_sendmsg+0xb5/0xf0 net/socket.c:657 ___sys_sendmsg+0x647/0x950 net/socket.c:2311 __sys_sendmsg+0xd9/0x180 net/socket.c:2356 __do_sys_sendmsg net/socket.c:2365 [inline] __se_sys_sendmsg net/socket.c:2363 [inline] __x64_sys_sendmsg+0x73/0xb0 net/socket.c:2363 do_syscall_64+0xca/0x5d0 arch/x86/entry/common.c:290 entry_SYSCALL_64_after_hwframe+0x49/0xbe Freed by task 7494: save_stack+0x21/0x90 mm/kasan/common.c:69 set_track mm/kasan/common.c:77 [inline] kasan_set_free_info mm/kasan/common.c:332 [inline] __kasan_slab_free+0x102/0x150 mm/kasan/common.c:471 kasan_slab_free+0xe/0x10 mm/kasan/common.c:480 __cache_free mm/slab.c:3425 [inline] kfree+0x108/0x2c0 mm/slab.c:3756 skb_free_head+0x6e/0x90 net/core/skbuff.c:591 skb_release_data+0x376/0x6a0 net/core/skbuff.c:611 skb_release_all+0x3d/0x50 net/core/skbuff.c:665 __kfree_skb net/core/skbuff.c:679 [inline] consume_skb+0xad/0x2a0 net/core/skbuff.c:838 netlink_unicast_kernel net/netlink/af_netlink.c:1303 [inline] netlink_unicast+0x447/0x630 net/netlink/af_netlink.c:1328 netlink_sendmsg+0x75d/0xc40 net/netlink/af_netlink.c:1917 sock_sendmsg_nosec net/socket.c:637 [inline] sock_sendmsg+0xb5/0xf0 net/socket.c:657 ___sys_sendmsg+0x647/0x950 net/socket.c:2311 __sys_sendmsg+0xd9/0x180 net/socket.c:2356 __do_sys_sendmsg net/socket.c:2365 [inline] __se_sys_sendmsg net/socket.c:2363 [inline] __x64_sys_sendmsg+0x73/0xb0 net/socket.c:2363 do_syscall_64+0xca/0x5d0 arch/x86/entry/common.c:290 entry_SYSCALL_64_after_hwframe+0x49/0xbe The buggy address belongs to the object at ffff888098f43500 which belongs to the cache kmalloc-512 of size 512 The buggy address is located 20 bytes inside of 512-byte region [ffff888098f43500, ffff888098f43700) The buggy address belongs to the page: page:ffffea000263d0c0 refcount:1 mapcount:0 mapping:ffff8880aa400a80 index:0x0 flags: 0x1fffc0000000200(slab) raw: 01fffc0000000200 ffffea0002647d88 ffffea0002648848 ffff8880aa400a80 raw: 0000000000000000 ffff888098f43000 0000000100000006 0000000000000000 page dumped because: kasan: bad access detected Memory state around the buggy address: ffff888098f43400: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff888098f43480: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc >ffff888098f43500: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ^ ffff888098f43580: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff888098f43600: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ==================================================================