==================================================================
BUG: KMSAN: uninit-value in slab_alloc_node mm/slub.c:2704 [inline]
BUG: KMSAN: uninit-value in slab_alloc mm/slub.c:2727 [inline]
BUG: KMSAN: uninit-value in __kmalloc_track_caller+0x7e3/0xc60 mm/slub.c:4322
CPU: 0 PID: 725 Comm: syz-executor0 Not tainted 4.19.0-rc1+ #41
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+0x14b/0x190 lib/dump_stack.c:113
 kmsan_report+0x183/0x2b0 mm/kmsan/kmsan.c:956
 __msan_warning+0x70/0xc0 mm/kmsan/kmsan_instr.c:645
 slab_alloc_node mm/slub.c:2704 [inline]
 slab_alloc mm/slub.c:2727 [inline]
 __kmalloc_track_caller+0x7e3/0xc60 mm/slub.c:4322
 kmemdup+0x95/0x140 mm/util.c:118
 netfilter_log_sysctl_init net/netfilter/nf_log.c:472 [inline]
 nf_log_net_init+0x155/0xae0 net/netfilter/nf_log.c:548
 ops_init+0x30b/0x770 net/core/net_namespace.c:129
 setup_net+0x263/0xf30 net/core/net_namespace.c:314
 copy_net_ns+0x473/0x8f0 net/core/net_namespace.c:437
 create_new_namespaces+0x8f8/0xde0 kernel/nsproxy.c:107
 unshare_nsproxy_namespaces+0x252/0x330 kernel/nsproxy.c:206
 ksys_unshare+0x89b/0x1140 kernel/fork.c:2491
 __do_sys_unshare kernel/fork.c:2559 [inline]
 __se_sys_unshare+0x41/0x60 kernel/fork.c:2557
 __x64_sys_unshare+0x32/0x50 kernel/fork.c:2557
 do_syscall_64+0xb8/0x100 arch/x86/entry/common.c:291
 entry_SYSCALL_64_after_hwframe+0x63/0xe7
RIP: 0033:0x457099
Code: fd b4 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 b4 fb ff c3 66 2e 0f 1f 84 00 00 00 00
RSP: 002b:00007fbd62338c78 EFLAGS: 00000246 ORIG_RAX: 0000000000000110
RAX: ffffffffffffffda RBX: 00007fbd623396d4 RCX: 0000000000457099
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000040000000
RBP: 00000000009300a0 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 00000000ffffffff
R13: 00000000004d78c0 R14: 00000000004ca76f R15: 0000000000000000

Uninit was created at:
 kmsan_save_stack_with_flags mm/kmsan/kmsan.c:256 [inline]
 kmsan_internal_poison_shadow+0xb8/0x1b0 mm/kmsan/kmsan.c:181
 kmsan_kmalloc+0x98/0x100 mm/kmsan/kmsan_hooks.c:91
 kmsan_slab_alloc+0x10/0x20 mm/kmsan/kmsan_hooks.c:100
 slab_post_alloc_hook mm/slab.h:446 [inline]
 slab_alloc_node mm/slub.c:2719 [inline]
 __kmalloc_node_track_caller+0x9e7/0x1160 mm/slub.c:4352
 __kmalloc_reserve net/core/skbuff.c:138 [inline]
 __alloc_skb+0x2f5/0x9e0 net/core/skbuff.c:206
 alloc_skb_fclone include/linux/skbuff.h:1038 [inline]
 sk_stream_alloc_skb+0x172/0xc90 net/ipv4/tcp.c:874
 tcp_fragment+0x43b/0x1f20 net/ipv4/tcp_output.c:1306
 tcp_write_wakeup+0x1154/0x1910 net/ipv4/tcp_output.c:3683
 tcp_send_probe0+0x7d/0x670 net/ipv4/tcp_output.c:3712
 tcp_probe_timer net/ipv4/tcp_timer.c:383 [inline]
 tcp_write_timer_handler+0xe84/0xea0 net/ipv4/tcp_timer.c:602
 tcp_write_timer+0x11e/0x270 net/ipv4/tcp_timer.c:618
 call_timer_fn+0x270/0x5b0 kernel/time/timer.c:1326
 expire_timers kernel/time/timer.c:1363 [inline]
 __run_timers+0xd94/0x11a0 kernel/time/timer.c:1682
 run_timer_softirq+0x2e/0x50 kernel/time/timer.c:1695
 __do_softirq+0x562/0x948 kernel/softirq.c:292
==================================================================