eal/windows: fix out-of-memory check in asprintf

Check vsnprintf() result to prevent calling malloc() with negative size.
Check actual malloc() result and terminate asprintf() with documented
error code to prevent the use of NULL pointer.

Fixes: e8428a9d8 ("eal/windows: add some basic functions and macros")

Signed-off-by: Dmitry Kozlyuk <dmitry.kozliuk@gmail.com>
Acked-by: Ranjit Menon <ranjit.menon@intel.com>

diff --git a/lib/librte_eal/windows/eal/include/rte_os.h b/lib/librte_eal/windows/eal/include/rte_os.h
index 9e76261..c76be12 100644 (file)
--- a/lib/librte_eal/windows/eal/include/rte_os.h
+++ b/lib/librte_eal/windows/eal/include/rte_os.h
@@ -64,12 +64,15 @@ asprintf(char **buffer, const char *format, ...)
        va_list arg;
 
        va_start(arg, format);
-       size = vsnprintf(NULL, 0, format, arg) + 1;
+       size = vsnprintf(NULL, 0, format, arg);
        va_end(arg);
+       if (size < 0)
+               return -1;
+       size++;
 
        *buffer = malloc(size);
-       if (buffer == NULL)
-               printf("Cannot allocate memory");
+       if (*buffer == NULL)
+               return -1;
 
        va_start(arg, format);
        ret = vsnprintf(*buffer, size, format, arg);