KMSAN: uninit-value in gc_worker (3)

[syzbot]

Hello,

syzbot found the following issue on:

HEAD commit: 6c24608b Update README.md
git tree: https://github.com/google/kmsan.git master
console output: https://syzkaller.appspot.com/x/log.txt?x=1292fd55900000
kernel config: https://syzkaller.appspot.com/x/.config?x=ee5f7a0b2e48ed66
dashboard link: https://syzkaller.appspot.com/bug?extid=b3dbc715a0b6201346f4
compiler: clang version 10.0.0 (https://github.com/llvm/llvm-project/ c2443155a0fb245c8f17f2c1c72b6ea391e86e81)

Unfortunately, I don't have any reproducer for this issue yet.

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+b3dbc7...@syzkaller.appspotmail.com

=====================================================
BUG: KMSAN: uninit-value in gc_worker+0x953/0x1740 net/netfilter/nf_conntrack_core.c:1389
CPU: 0 PID: 12 Comm: kworker/0:1 Not tainted 5.8.0-rc5-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Workqueue: events_power_efficient gc_worker
Call Trace:
__dump_stack lib/dump_stack.c:77 [inline]
dump_stack+0x21c/0x280 lib/dump_stack.c:118
kmsan_report+0xf7/0x1e0 mm/kmsan/kmsan_report.c:121
__msan_warning+0x58/0xa0 mm/kmsan/kmsan_instr.c:215
gc_worker+0x953/0x1740 net/netfilter/nf_conntrack_core.c:1389
process_one_work+0x1688/0x2140 kernel/workqueue.c:2269
worker_thread+0x10bc/0x2730 kernel/workqueue.c:2415
kthread+0x551/0x590 kernel/kthread.c:292
ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:293

Uninit was created at:
kmsan_save_stack_with_flags+0x3c/0x90 mm/kmsan/kmsan.c:144
kmsan_internal_alloc_meta_for_pages mm/kmsan/kmsan_shadow.c:269 [inline]
kmsan_alloc_page+0xc5/0x1a0 mm/kmsan/kmsan_shadow.c:293
__alloc_pages_nodemask+0xdf0/0x1030 mm/page_alloc.c:4889
alloc_pages_current+0x685/0xb50 mm/mempolicy.c:2292
alloc_pages include/linux/gfp.h:545 [inline]
alloc_slab_page+0x11c/0x1240 mm/slub.c:1560
allocate_slab mm/slub.c:1705 [inline]
new_slab+0x2bf/0x10c0 mm/slub.c:1771
new_slab_objects mm/slub.c:2528 [inline]
___slab_alloc+0xcd3/0x18a0 mm/slub.c:2689
__slab_alloc mm/slub.c:2729 [inline]
slab_alloc_node mm/slub.c:2803 [inline]
slab_alloc mm/slub.c:2848 [inline]
kmem_cache_alloc+0xb70/0xc50 mm/slub.c:2853
__nf_conntrack_alloc+0x1a9/0x790 net/netfilter/nf_conntrack_core.c:1509
init_conntrack+0x3c2/0x2180 net/netfilter/nf_conntrack_core.c:1588
resolve_normal_ct net/netfilter/nf_conntrack_core.c:1686 [inline]
nf_conntrack_in+0x158a/0x2b10 net/netfilter/nf_conntrack_core.c:1846
ipv6_conntrack_local+0x68/0x80 net/netfilter/nf_conntrack_proto.c:398
nf_hook_entry_hookfn include/linux/netfilter.h:135 [inline]
nf_hook_slow+0x17b/0x460 net/netfilter/core.c:512
nf_hook include/linux/netfilter.h:262 [inline]
NF_HOOK include/linux/netfilter.h:305 [inline]
ip6_xmit+0x2301/0x2b40 net/ipv6/ip6_output.c:280
inet6_csk_xmit+0x47f/0x5a0 net/ipv6/inet6_connection_sock.c:135
__tcp_transmit_skb+0x4b9e/0x5d70 net/ipv4/tcp_output.c:1240
tcp_transmit_skb net/ipv4/tcp_output.c:1256 [inline]
tcp_connect+0x153f/0x3bb0 net/ipv4/tcp_output.c:3673
tcp_v6_connect+0x2be8/0x2d40 net/ipv6/tcp_ipv6.c:334
__inet_stream_connect+0x14fe/0x16f0 net/ipv4/af_inet.c:658
inet_stream_connect+0x101/0x180 net/ipv4/af_inet.c:722
rds_tcp_conn_path_connect+0x93d/0xcc0 net/rds/tcp_connect.c:172
rds_connect_worker+0x36b/0x550 net/rds/threads.c:176
process_one_work+0x1688/0x2140 kernel/workqueue.c:2269
worker_thread+0x10bc/0x2730 kernel/workqueue.c:2415
kthread+0x551/0x590 kernel/kthread.c:292
ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:293
=====================================================


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[syzbot]

Auto-closing this bug as obsolete.
Crashes did not happen for a while, no reproducer and no activity.