odhcpd: fix passing possible negative parameter

Prevent passing negative argument to read; detected by Coverity in CID1412381

Signed-off-by: Hans Dedecker <dedeckeh@gmail.com>

diff --git a/src/odhcpd.c b/src/odhcpd.c
index 0e0002d95159e402e4c004b76021312ec58c667c..7c6c144112e076efc37ac2c38bb55fb3c33ef3d5 100644 (file)
--- a/src/odhcpd.c
+++ b/src/odhcpd.c
@@ -128,6 +128,9 @@ int odhcpd_get_interface_config(const char *ifname, const char *what)
        snprintf(buf, sizeof(buf), sysctl_pattern, ifname, what);
 
        int fd = open(buf, O_RDONLY);
+       if (fd < 0)
+               return -1;
+
        ssize_t len = read(fd, buf, sizeof(buf) - 1);
        close(fd);