From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([2001:4830:134:3::10]:51958) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1Xdge1-0000kX-7M for qemu-devel@nongnu.org; Mon, 13 Oct 2014 10:30:50 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1Xdgds-0000uB-0j for qemu-devel@nongnu.org; Mon, 13 Oct 2014 10:30:41 -0400 Message-ID: <543BE352.3080609@gmail.com> Date: Mon, 13 Oct 2014 22:36:02 +0800 From: Chen Gang MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: 7bit Subject: [Qemu-devel] [PATCH] target-ppc: kvm: Fix memory overflow issue about strncat() List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: agraf@suse.de, pbonzini@redhat.com Cc: qemu-trivial@nongnu.org, qemu-ppc@nongnu.org, qemu-devel , kvm@vger.kernel.org strncat() will append additional '\0' to destination buffer, so need additional 1 byte for it, or may cause memory overflow, just like other area within QEMU have done. Signed-off-by: Chen Gang --- target-ppc/kvm.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) diff --git a/target-ppc/kvm.c b/target-ppc/kvm.c index 9c23c6b..66e7ce5 100644 --- a/target-ppc/kvm.c +++ b/target-ppc/kvm.c @@ -1794,8 +1794,8 @@ static uint64_t kvmppc_read_int_cpu_dt(const char *propname) return -1; } - strncat(buf, "/", sizeof(buf) - strlen(buf)); - strncat(buf, propname, sizeof(buf) - strlen(buf)); + strncat(buf, "/", sizeof(buf) - strlen(buf) - 1); + strncat(buf, propname, sizeof(buf) - strlen(buf) - 1); f = fopen(buf, "rb"); if (!f) { -- 1.9.3