eal: check vsnprintf failure in devargs parsing

Check for failure, while here just increment len once after checking for
failure instead of duplicating len + 1 math in two different argument
lists.

Signed-off-by: Tyler Retzlaff <roretzla@linux.microsoft.com>

diff --git a/lib/librte_eal/common/eal_common_devargs.c b/lib/librte_eal/common/eal_common_devargs.c
index e40b91e..4b5be80 100644 (file)
--- a/lib/librte_eal/common/eal_common_devargs.c
+++ b/lib/librte_eal/common/eal_common_devargs.c
@@ -242,7 +242,7 @@ int
 rte_devargs_parsef(struct rte_devargs *da, const char *format, ...)
 {
        va_list ap;
-       size_t len;
+       int len;
        char *dev;
        int ret;
 
@@ -252,15 +252,18 @@ rte_devargs_parsef(struct rte_devargs *da, const char *format, ...)
        va_start(ap, format);
        len = vsnprintf(NULL, 0, format, ap);
        va_end(ap);
+       if (len < 0)
+               return -EINVAL;
 
-       dev = calloc(1, len + 1);
+       len += 1;
+       dev = calloc(1, (size_t)len);
        if (dev == NULL) {
                RTE_LOG(ERR, EAL, "not enough memory to parse device\n");
                return -ENOMEM;
        }
 
        va_start(ap, format);
-       vsnprintf(dev, len + 1, format, ap);
+       vsnprintf(dev, (size_t)len, format, ap);
        va_end(ap);
 
        ret = rte_devargs_parse(da, dev);