From 9d0bd0cdd011edf15949ecdf08c25d8385028983 Mon Sep 17 00:00:00 2001 From: Peter Maydell Date: Tue, 5 Feb 2019 17:42:07 +0000 Subject: [PATCH] linux-user: Check sscanf return value in open_net_route() MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit 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 Reviewed-by: Philippe Mathieu-Daudé Reviewed-by: Stefano Garzarella Reviewed-by: Laurent Vivier Message-Id: <20190205174207.9278-1-peter.maydell@linaro.org> Signed-off-by: Laurent Vivier --- 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 08acc4d860..5bbb72f3d5 100644 --- a/linux-user/syscall.c +++ b/linux-user/syscall.c @@ -6768,9 +6768,15 @@ 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);