From ceddcac74a6eafae8d959adcbfee17d4cae2c3a8 Mon Sep 17 00:00:00 2001 From: Stefano Brivio Date: Tue, 5 Apr 2022 12:33:31 +0200 Subject: [PATCH] conf, tap: False "Buffer not null terminated" positives, CWE-170 Those strings are actually guaranteed to be NULL-terminated. Reported by Coverity. Signed-off-by: Stefano Brivio --- conf.c | 6 +++--- tap.c | 6 +++--- 2 files changed, 6 insertions(+), 6 deletions(-) diff --git a/conf.c b/conf.c index 2412fc6..5c614cd 100644 --- a/conf.c +++ b/conf.c @@ -1035,7 +1035,7 @@ void conf(struct ctx *c, int argc, char **argv) usage(argv[0]); } - ret = snprintf(c->sock_path, sizeof(c->sock_path), "%s", + ret = snprintf(c->sock_path, UNIX_SOCK_MAX - 1, "%s", optarg); if (ret <= 0 || ret >= (int)sizeof(c->pcap)) { err("Invalid socket path: %s", optarg); @@ -1048,9 +1048,9 @@ void conf(struct ctx *c, int argc, char **argv) usage(argv[0]); } - ret = snprintf(c->pasta_ifn, sizeof(c->pasta_ifn), "%s", + ret = snprintf(c->pasta_ifn, IFNAMSIZ - 1, "%s", optarg); - if (ret <= 0 || ret >= (int)sizeof(c->pasta_ifn)) { + if (ret <= 0 || ret >= IFNAMSIZ - 1) { err("Invalid interface name: %s", optarg); usage(argv[0]); } diff --git a/tap.c b/tap.c index 8110577..04ceade 100644 --- a/tap.c +++ b/tap.c @@ -798,9 +798,9 @@ static void tap_sock_unix_init(struct ctx *c) char *path = addr.sun_path; if (*c->sock_path) - strncpy(path, c->sock_path, UNIX_PATH_MAX); + memcpy(path, c->sock_path, UNIX_PATH_MAX); else - snprintf(path, UNIX_PATH_MAX, UNIX_SOCK_PATH, i); + snprintf(path, UNIX_PATH_MAX - 1, UNIX_SOCK_PATH, i); ex = socket(AF_UNIX, SOCK_STREAM | SOCK_NONBLOCK, 0); if (ex < 0) { @@ -899,7 +899,7 @@ static int tap_ns_tun(void *arg) int flags = O_RDWR | O_NONBLOCK | O_CLOEXEC; struct ctx *c = (struct ctx *)arg; - strncpy(ifr.ifr_name, c->pasta_ifn, IFNAMSIZ); + memcpy(ifr.ifr_name, c->pasta_ifn, IFNAMSIZ); if (ns_enter(c) || (tun_ns_fd = open("/dev/net/tun", flags)) < 0 ||