KMSAN: uninit-value in strlcpy (2)

KMSAN: uninit-value in strlcpy (2)
Status: upstream: reported C repro on 2018/09/14 18:23
Reported-by: syzbot+c86cf7903306a6c201ba@syzkaller.appspotmail.com
First crash: 786d, last: 674d

similar bugs (1):
Kernel	Title	Repro	Bisected	Count	Last	Reported	Patched	Status
upstream	KMSAN: uninit-value in strlcpy	C		2	796d	796d	6/17	fixed on 2018/05/08 18:30

Sample crash report:

random: sshd: uninitialized urandom read (32 bytes read)
random: sshd: uninitialized urandom read (32 bytes read)
random: sshd: uninitialized urandom read (32 bytes read)
random: sshd: uninitialized urandom read (32 bytes read)
==================================================================
BUG: KMSAN: uninit-value in strlen lib/string.c:482 [inline]
BUG: KMSAN: uninit-value in strlcpy+0x68/0x1c0 lib/string.c:142
CPU: 0 PID: 4506 Comm: syz-executor160 Not tainted 4.17.0-rc5+ #95
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+0x185/0x1d0 lib/dump_stack.c:113
 kmsan_report+0x142/0x240 mm/kmsan/kmsan.c:1084
 __msan_warning_32+0x6c/0xb0 mm/kmsan/kmsan_instr.c:683
 strlen lib/string.c:482 [inline]
 strlcpy+0x68/0x1c0 lib/string.c:142
 do_ip_vs_set_ctl+0x3f1/0x2760 net/netfilter/ipvs/ip_vs_ctl.c:2384
 nf_sockopt net/netfilter/nf_sockopt.c:106 [inline]
 nf_setsockopt+0x476/0x4d0 net/netfilter/nf_sockopt.c:115
 ip_setsockopt+0x24b/0x2b0 net/ipv4/ip_sockglue.c:1253
 udp_setsockopt+0x108/0x1b0 net/ipv4/udp.c:2416
 ipv6_setsockopt+0x30c/0x340 net/ipv6/ipv6_sockglue.c:917
 tcp_setsockopt+0x1bb/0x1f0 net/ipv4/tcp.c:2891
 sock_common_setsockopt+0x136/0x170 net/core/sock.c:3039
 __sys_setsockopt+0x4af/0x560 net/socket.c:1903
 __do_sys_setsockopt net/socket.c:1914 [inline]
 __se_sys_setsockopt net/socket.c:1911 [inline]
 __x64_sys_setsockopt+0x15c/0x1c0 net/socket.c:1911
 do_syscall_64+0x154/0x220 arch/x86/entry/common.c:287
 entry_SYSCALL_64_after_hwframe+0x44/0xa9
RIP: 0033:0x43fce9
RSP: 002b:00007ffea6b1dd08 EFLAGS: 00000213 ORIG_RAX: 0000000000000036
RAX: ffffffffffffffda RBX: 00000000004002c8 RCX: 000000000043fce9
RDX: 000000000000048b RSI: 0000000000000000 RDI: 0000000000000003
RBP: 00000000006ca018 R08: 0000000000000018 R09: 00000000004002c8
R10: 00000000200001c0 R11: 0000000000000213 R12: 0000000000401610
R13: 00000000004016a0 R14: 0000000000000000 R15: 0000000000000000

Local variable description: ----arg@do_ip_vs_set_ctl
Variable was created at:
 read_pnet include/net/net_namespace.h:288 [inline]
 sock_net include/net/sock.h:2306 [inline]
 do_ip_vs_set_ctl+0x93/0x2760 net/netfilter/ipvs/ip_vs_ctl.c:2347
 nf_sockopt net/netfilter/nf_sockopt.c:106 [inline]
 nf_setsockopt+0x476/0x4d0 net/netfilter/nf_sockopt.c:115
==================================================================

Crashes (6):
Manager	Time	Kernel	Commit	Syzkaller	Config	Log	Report	Syz repro	C repro	Maintainers
ci-upstream-kmsan-gce	2018/05/16 12:38	https://github.com/google/kmsan.git master	9822946c	75b2448a	.config	log	report	syz	C	coreteam@netfilter.org, davem@davemloft.net, fw@strlen.de, horms@verge.net.au, ja@ssi.bg, kadlec@blackhole.kfki.hu, linux-kernel@vger.kernel.org, lvs-devel@vger.kernel.org, netdev@vger.kernel.org, netfilter-devel@vger.kernel.org, pablo@netfilter.org, wensong@linux-vs.org
ci-upstream-kmsan-gce	2018/09/05 06:19	https://github.com/google/kmsan.git master	28f0ca98	a4718693	.config	log	report			alsa-devel@alsa-project.org, linux-kernel@vger.kernel.org, perex@perex.cz, tiwai@suse.com
ci-upstream-kmsan-gce	2018/06/06 18:03	https://github.com/google/kmsan.git master	b9a5d319	41f9540d	.config	log	report			coreteam@netfilter.org, davem@davemloft.net, fw@strlen.de, horms@verge.net.au, ja@ssi.bg, kadlec@blackhole.kfki.hu, linux-kernel@vger.kernel.org, lvs-devel@vger.kernel.org, netdev@vger.kernel.org, netfilter-devel@vger.kernel.org, pablo@netfilter.org, wensong@linux-vs.org
ci-upstream-kmsan-gce	2018/06/03 21:02	https://github.com/google/kmsan.git master	8fc8ecd1	2f93b54f	.config	log	report			coreteam@netfilter.org, davem@davemloft.net, fw@strlen.de, horms@verge.net.au, ja@ssi.bg, kadlec@blackhole.kfki.hu, linux-kernel@vger.kernel.org, lvs-devel@vger.kernel.org, netdev@vger.kernel.org, netfilter-devel@vger.kernel.org, pablo@netfilter.org, wensong@linux-vs.org
ci-upstream-kmsan-gce	2018/05/29 07:24	https://github.com/google/kmsan.git master	1b9cd4ec	f48c20b8	.config	log	report			coreteam@netfilter.org, davem@davemloft.net, fw@strlen.de, horms@verge.net.au, ja@ssi.bg, kadlec@blackhole.kfki.hu, linux-kernel@vger.kernel.org, lvs-devel@vger.kernel.org, netdev@vger.kernel.org, netfilter-devel@vger.kernel.org, pablo@netfilter.org, wensong@linux-vs.org
ci-upstream-kmsan-gce	2018/05/16 12:12	https://github.com/google/kmsan.git master	9822946c	75b2448a	.config	log	report			coreteam@netfilter.org, davem@davemloft.net, fw@strlen.de, horms@verge.net.au, ja@ssi.bg, kadlec@blackhole.kfki.hu, linux-kernel@vger.kernel.org, lvs-devel@vger.kernel.org, netdev@vger.kernel.org, netfilter-devel@vger.kernel.org, pablo@netfilter.org, wensong@linux-vs.org