RBP: 000000000078bf00 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000004 R13: 0000000000000a24 R14: 00000000004cd053 R15: 00007f69654456d4 ================================================================== BUG: KASAN: use-after-free in nla_len include/net/netlink.h:1135 [inline] BUG: KASAN: use-after-free in nla_parse_nested_deprecated include/net/netlink.h:1218 [inline] BUG: KASAN: use-after-free in tipc_nl_node_dump_link+0xc4e/0xc80 net/tipc/node.c:2591 Read of size 2 at addr ffff88809ab34814 by task syz-executor.0/12981 CPU: 0 PID: 12981 Comm: syz-executor.0 Not tainted 5.8.0-rc3-syzkaller #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+0x1f0/0x31e lib/dump_stack.c:118 print_address_description+0x66/0x5a0 mm/kasan/report.c:383 __kasan_report mm/kasan/report.c:513 [inline] kasan_report+0x132/0x1d0 mm/kasan/report.c:530 nla_len include/net/netlink.h:1135 [inline] nla_parse_nested_deprecated include/net/netlink.h:1218 [inline] tipc_nl_node_dump_link+0xc4e/0xc80 net/tipc/node.c:2591 genl_lock_dumpit+0x86/0xa0 net/netlink/genetlink.c:575 netlink_dump+0x4be/0x10d0 net/netlink/af_netlink.c:2245 __netlink_dump_start+0x538/0x700 net/netlink/af_netlink.c:2353 genl_family_rcv_msg_dumpit net/netlink/genetlink.c:638 [inline] genl_family_rcv_msg net/netlink/genetlink.c:733 [inline] genl_rcv_msg+0xb03/0xe00 net/netlink/genetlink.c:753 netlink_rcv_skb+0x190/0x3a0 net/netlink/af_netlink.c:2469 genl_rcv+0x24/0x40 net/netlink/genetlink.c:764 netlink_unicast_kernel net/netlink/af_netlink.c:1303 [inline] netlink_unicast+0x786/0x940 net/netlink/af_netlink.c:1329 netlink_sendmsg+0xa57/0xd70 net/netlink/af_netlink.c:1918 sock_sendmsg_nosec net/socket.c:652 [inline] sock_sendmsg net/socket.c:672 [inline] ____sys_sendmsg+0x519/0x800 net/socket.c:2352 ___sys_sendmsg net/socket.c:2406 [inline] __sys_sendmsg+0x2b1/0x360 net/socket.c:2439 do_syscall_64+0x73/0xe0 arch/x86/entry/common.c:359 entry_SYSCALL_64_after_hwframe+0x44/0xa9 RIP: 0033:0x45cb29 Code: Bad RIP value. RSP: 002b:00007f6965444c78 EFLAGS: 00000246 ORIG_RAX: 000000000000002e RAX: ffffffffffffffda RBX: 0000000000501fa0 RCX: 000000000045cb29 RDX: 0000000000000000 RSI: 0000000020000000 RDI: 0000000000000003 RBP: 000000000078bf00 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000004 R13: 0000000000000a24 R14: 00000000004cd053 R15: 00007f69654456d4 Allocated by task 12987: save_stack mm/kasan/common.c:48 [inline] set_track mm/kasan/common.c:56 [inline] __kasan_kmalloc+0x103/0x140 mm/kasan/common.c:494 __kmalloc_reserve net/core/skbuff.c:142 [inline] __alloc_skb+0xde/0x4f0 net/core/skbuff.c:210 alloc_skb include/linux/skbuff.h:1083 [inline] netlink_alloc_large_skb net/netlink/af_netlink.c:1175 [inline] netlink_sendmsg+0x7b2/0xd70 net/netlink/af_netlink.c:1893 sock_sendmsg_nosec net/socket.c:652 [inline] sock_sendmsg net/socket.c:672 [inline] ____sys_sendmsg+0x519/0x800 net/socket.c:2352 ___sys_sendmsg net/socket.c:2406 [inline] __sys_sendmsg+0x2b1/0x360 net/socket.c:2439 do_syscall_64+0x73/0xe0 arch/x86/entry/common.c:359 entry_SYSCALL_64_after_hwframe+0x44/0xa9 Freed by task 12987: save_stack mm/kasan/common.c:48 [inline] set_track mm/kasan/common.c:56 [inline] kasan_set_free_info mm/kasan/common.c:316 [inline] __kasan_slab_free+0x114/0x170 mm/kasan/common.c:455 __cache_free mm/slab.c:3426 [inline] kfree+0x10a/0x220 mm/slab.c:3757 skb_release_all net/core/skbuff.c:664 [inline] __kfree_skb+0x56/0x1c0 net/core/skbuff.c:678 netlink_unicast_kernel net/netlink/af_netlink.c:1304 [inline] netlink_unicast+0x78e/0x940 net/netlink/af_netlink.c:1329 netlink_sendmsg+0xa57/0xd70 net/netlink/af_netlink.c:1918 sock_sendmsg_nosec net/socket.c:652 [inline] sock_sendmsg net/socket.c:672 [inline] ____sys_sendmsg+0x519/0x800 net/socket.c:2352 ___sys_sendmsg net/socket.c:2406 [inline] __sys_sendmsg+0x2b1/0x360 net/socket.c:2439 do_syscall_64+0x73/0xe0 arch/x86/entry/common.c:359 entry_SYSCALL_64_after_hwframe+0x44/0xa9 The buggy address belongs to the object at ffff88809ab34800 which belongs to the cache kmalloc-512 of size 512 The buggy address is located 20 bytes inside of 512-byte region [ffff88809ab34800, ffff88809ab34a00) The buggy address belongs to the page: page:ffffea00026acd00 refcount:1 mapcount:0 mapping:0000000000000000 index:0xffff88809ab34000 flags: 0xfffe0000000200(slab) raw: 00fffe0000000200 ffffea0002871c48 ffffea00025f2288 ffff8880aa400a80 raw: ffff88809ab34000 ffff88809ab34000 0000000100000002 0000000000000000 page dumped because: kasan: bad access detected Memory state around the buggy address: ffff88809ab34700: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ffff88809ab34780: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc >ffff88809ab34800: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ^ ffff88809ab34880: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff88809ab34900: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ==================================================================