From mboxrd@z Thu Jan 1 00:00:00 1970 From: Ying Xue Subject: Re: KMSAN: uninit-value in strcmp Date: Tue, 8 May 2018 21:12:14 +0800 Message-ID: References: <00000000000059f907056b519603@google.com> <20180503.152213.740988890883315228.davem@davemloft.net> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Cc: netdev@vger.kernel.org, syzkaller-bugs@googlegroups.com, linux-kernel@vger.kernel.org, tipc-discussion@lists.sourceforge.net To: David Miller , Return-path: In-Reply-To: <20180503.152213.740988890883315228.davem@davemloft.net> Content-Language: en-US List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: tipc-discussion-bounces@lists.sourceforge.net List-Id: netdev.vger.kernel.org On 05/04/2018 03:22 AM, David Miller wrote: > From: syzbot > Date: Thu, 03 May 2018 11:44:02 -0700 > >> Call Trace: >> __dump_stack lib/dump_stack.c:17 [inline] >> dump_stack+0x185/0x1d0 lib/dump_stack.c:53 >> kmsan_report+0x142/0x240 mm/kmsan/kmsan.c:1067 >> __msan_warning_32+0x6c/0xb0 mm/kmsan/kmsan_instr.c:683 >> strcmp+0xf7/0x160 lib/string.c:329 >> tipc_nl_node_get_link+0x220/0x6f0 net/tipc/node.c:1881 >> genl_family_rcv_msg net/netlink/genetlink.c:599 [inline] > > Hmmm, TIPC_NL_LINK_GET uses tipc_nl_policy, which has a proper nesting > entry for TIPC_NLA_LINK. I wonder how the code goes about validating > TIPC_NLA_LINK_NAME in such a case? Does it? > > This may be the problem. David, you are right. This is absolutely a real bug. As you said, we didn't validate TIPC_NLA_LINK_NAME attribute in tipc_nl_node_get_link() at all. I will submit a patch to fix the issue soon. > ------------------------------------------------------------------------------ Check out the vibrant tech community on one of the world's most engaging tech sites, Slashdot.org! http://sdm.link/slashdot