From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([209.51.188.92]:51153) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1gr4k2-0007Zj-Pg for qemu-devel@nongnu.org; Tue, 05 Feb 2019 12:42:41 -0500 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1gr4k0-0001Vl-Br for qemu-devel@nongnu.org; Tue, 05 Feb 2019 12:42:38 -0500 Received: from mail-wr1-x443.google.com ([2a00:1450:4864:20::443]:40799) by eggs.gnu.org with esmtps (TLS1.0:RSA_AES_128_CBC_SHA1:16) (Exim 4.71) (envelope-from ) id 1gr4jz-0001JF-Uh for qemu-devel@nongnu.org; Tue, 05 Feb 2019 12:42:36 -0500 Received: by mail-wr1-x443.google.com with SMTP id p4so4589227wrt.7 for ; Tue, 05 Feb 2019 09:42:11 -0800 (PST) From: Peter Maydell Date: Tue, 5 Feb 2019 17:42:07 +0000 Message-Id: <20190205174207.9278-1-peter.maydell@linaro.org> MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Subject: [Qemu-devel] [PATCH] linux-user: Check sscanf return value in open_net_route() List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: qemu-devel@nongnu.org Cc: patches@linaro.org, Laurent Vivier , Riku Voipio Coverity warns (CID 1390634) that open_net_route() is not checking the return value from sscanf(), which means that it might then use values that aren't initialized. Errors here should in general not happen since we're passing an assumed-good /proc/net/route from the host kernel, but if we do fail to parse a line then just skip it in the output we pass to the guest. Signed-off-by: Peter Maydell --- linux-user/syscall.c | 12 +++++++++--- 1 file changed, 9 insertions(+), 3 deletions(-) diff --git a/linux-user/syscall.c b/linux-user/syscall.c index b5786d4fc1f..894678aa8b4 100644 --- a/linux-user/syscall.c +++ b/linux-user/syscall.c @@ -6762,9 +6762,15 @@ static int open_net_route(void *cpu_env, int fd) char iface[16]; uint32_t dest, gw, mask; unsigned int flags, refcnt, use, metric, mtu, window, irtt; - sscanf(line, "%s\t%08x\t%08x\t%04x\t%d\t%d\t%d\t%08x\t%d\t%u\t%u\n", - iface, &dest, &gw, &flags, &refcnt, &use, &metric, - &mask, &mtu, &window, &irtt); + int fields; + + fields = sscanf(line, + "%s\t%08x\t%08x\t%04x\t%d\t%d\t%d\t%08x\t%d\t%u\t%u\n", + iface, &dest, &gw, &flags, &refcnt, &use, &metric, + &mask, &mtu, &window, &irtt); + if (fields != 11) { + continue; + } dprintf(fd, "%s\t%08x\t%08x\t%04x\t%d\t%d\t%d\t%08x\t%d\t%u\t%u\n", iface, tswap32(dest), tswap32(gw), flags, refcnt, use, metric, tswap32(mask), mtu, window, irtt); -- 2.20.1