netlink: 4 bytes leftover after parsing attributes in process `syz-executor.5'. ===================================================== BUG: KMSAN: uninit-value in vsnprintf+0x218f/0x3210 lib/vsprintf.c:2503 CPU: 1 PID: 16461 Comm: syz-executor.5 Not tainted 5.3.0-rc7+ #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+0x191/0x1f0 lib/dump_stack.c:113 kmsan_report+0x13a/0x2b0 mm/kmsan/kmsan_report.c:108 __msan_warning+0x73/0xe0 mm/kmsan/kmsan_instr.c:250 string_nocheck lib/vsprintf.c:606 [inline] string+0x4be/0x600 lib/vsprintf.c:668 vsnprintf+0x218f/0x3210 lib/vsprintf.c:2503 __request_module+0x2b1/0x11c0 kernel/kmod.c:143 tcf_proto_lookup_ops+0x171/0x700 net/sched/cls_api.c:80 tcf_proto_create net/sched/cls_api.c:192 [inline] tc_new_tfilter+0x2ebd/0x4ce0 net/sched/cls_api.c:2106 rtnetlink_rcv_msg+0xcb6/0x1580 net/core/rtnetlink.c:5214 netlink_rcv_skb+0x431/0x620 net/netlink/af_netlink.c:2477 rtnetlink_rcv+0x50/0x60 net/core/rtnetlink.c:5241 netlink_unicast_kernel net/netlink/af_netlink.c:1302 [inline] netlink_unicast+0xf6c/0x1050 net/netlink/af_netlink.c:1328 netlink_sendmsg+0x110f/0x1330 net/netlink/af_netlink.c:1917 sock_sendmsg_nosec net/socket.c:637 [inline] sock_sendmsg net/socket.c:657 [inline] ___sys_sendmsg+0x14ff/0x1590 net/socket.c:2311 __sys_sendmmsg+0x53a/0xae0 net/socket.c:2413 __do_sys_sendmmsg net/socket.c:2442 [inline] __se_sys_sendmmsg+0xbd/0xe0 net/socket.c:2439 __x64_sys_sendmmsg+0x56/0x70 net/socket.c:2439 do_syscall_64+0xbc/0xf0 arch/x86/entry/common.c:297 entry_SYSCALL_64_after_hwframe+0x63/0xe7 RIP: 0033:0x459a29 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:00007fcbde48ec78 EFLAGS: 00000246 ORIG_RAX: 0000000000000133 RAX: ffffffffffffffda RBX: 0000000000000004 RCX: 0000000000459a29 RDX: 0000000000000332 RSI: 0000000020000140 RDI: 0000000000000006 RBP: 000000000075bf20 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 00007fcbde48f6d4 R13: 00000000004c722e R14: 00000000004dcac0 R15: 00000000ffffffff Uninit was created at: kmsan_save_stack_with_flags mm/kmsan/kmsan.c:150 [inline] kmsan_internal_poison_shadow+0x53/0x100 mm/kmsan/kmsan.c:134 kmsan_slab_alloc+0xaa/0x120 mm/kmsan/kmsan_hooks.c:103 slab_alloc_node mm/slub.c:2790 [inline] __kmalloc_node_track_caller+0xb55/0x1320 mm/slub.c:4388 __kmalloc_reserve net/core/skbuff.c:141 [inline] __alloc_skb+0x306/0xa10 net/core/skbuff.c:209 alloc_skb include/linux/skbuff.h:1056 [inline] netlink_alloc_large_skb net/netlink/af_netlink.c:1174 [inline] netlink_sendmsg+0x783/0x1330 net/netlink/af_netlink.c:1892 sock_sendmsg_nosec net/socket.c:637 [inline] sock_sendmsg net/socket.c:657 [inline] ___sys_sendmsg+0x14ff/0x1590 net/socket.c:2311 __sys_sendmmsg+0x53a/0xae0 net/socket.c:2413 __do_sys_sendmmsg net/socket.c:2442 [inline] __se_sys_sendmmsg+0xbd/0xe0 net/socket.c:2439 __x64_sys_sendmmsg+0x56/0x70 net/socket.c:2439 do_syscall_64+0xbc/0xf0 arch/x86/entry/common.c:297 entry_SYSCALL_64_after_hwframe+0x63/0xe7 =====================================================