From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([2001:4830:134:3::10]:59309) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1YXRRU-0007se-2n for qemu-devel@nongnu.org; Mon, 16 Mar 2015 05:36:13 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1YXRRS-0002Zd-Og for qemu-devel@nongnu.org; Mon, 16 Mar 2015 05:36:12 -0400 Message-ID: <5506A2B0.3030208@huawei.com> Date: Mon, 16 Mar 2015 17:30:24 +0800 From: Shannon Zhao MIME-Version: 1.0 References: <1426244956-5316-1-git-send-email-zhaoshenglong@huawei.com> <87egopmkzo.fsf@linux.vnet.ibm.com> In-Reply-To: <87egopmkzo.fsf@linux.vnet.ibm.com> Content-Type: text/plain; charset="ISO-8859-1" Content-Transfer-Encoding: 7bit Subject: Re: [Qemu-devel] [PATCH] hw/9pfs/virtio-9p-proxy: Fix possible overflow List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: "Aneesh Kumar K.V" , qemu-devel@nongnu.org Cc: peter.maydell@linaro.org, hangaohuai@huawei.com, qemu-trivial@nongnu.org, mjt@tls.msk.ru, peter.huangpeng@huawei.com, shannon.zhao@linaro.org, pbonzini@redhat.com On 2015/3/16 15:58, Aneesh Kumar K.V wrote: > Shannon Zhao writes: > >> It's detected by coverity. As max of sockaddr_un.sun_path is >> sizeof(helper.sun_path), should check the length of source >> and use strncpy instead of strcpy. >> >> Signed-off-by: Shannon Zhao >> Signed-off-by: Shannon Zhao >> --- >> hw/9pfs/virtio-9p-proxy.c | 3 ++- >> 1 file changed, 2 insertions(+), 1 deletion(-) >> >> diff --git a/hw/9pfs/virtio-9p-proxy.c b/hw/9pfs/virtio-9p-proxy.c >> index 59c7445..fb1ab7b 100644 >> --- a/hw/9pfs/virtio-9p-proxy.c >> +++ b/hw/9pfs/virtio-9p-proxy.c >> @@ -1102,12 +1102,13 @@ static int connect_namedsocket(const char *path) >> int sockfd, size; >> struct sockaddr_un helper; >> >> + g_assert(strlen(path) < sizeof(helper.sun_path)); > > Since we are doing this from within Qemu, I did the below and folded > that into other sockadd_un.sun_path size checking patch. > > diff --git a/hw/9pfs/virtio-9p-proxy.c b/hw/9pfs/virtio-9p-proxy.c > index 6bb191ee6ab8..71b6198bbd22 100644 > --- a/hw/9pfs/virtio-9p-proxy.c > +++ b/hw/9pfs/virtio-9p-proxy.c > @@ -1100,6 +1100,10 @@ static int connect_namedsocket(const char *path) > int sockfd, size; > struct sockaddr_un helper; > > + if (strlen(path) >= sizeof(helper.sun_path)) { > + fprintf(stderr, "Socket name too large\n"); > + return -1; > + } > sockfd = socket(AF_UNIX, SOCK_STREAM, 0); > if (sockfd < 0) { > fprintf(stderr, "failed to create socket: %s\n", strerror(errno)); > > > Let me know if that is ok for you. > That's OK. :-) -- Thanks, Shannon >> sockfd = socket(AF_UNIX, SOCK_STREAM, 0); >> if (sockfd < 0) { >> fprintf(stderr, "failed to create socket: %s\n", strerror(errno)); >> return -1; >> } >> - strcpy(helper.sun_path, path); >> + strncpy(helper.sun_path, path, sizeof(helper.sun_path)); >> helper.sun_family = AF_UNIX; >> size = strlen(helper.sun_path) + sizeof(helper.sun_family); >> if (connect(sockfd, (struct sockaddr *)&helper, size) < 0) { >> -- >> 1.8.3.1 > > > . >