[vlc-devel] [PATCH] memstream: vlc_memstream_vprintf: handle vsnprintf failure

[Filip Roséen]

If there is an output error in the call to vsnprintf in "len = vsnprintf( ... )",
len would be negative; leading to undefined-behavior further down the road.

---
 src/text/memstream.c | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/src/text/memstream.c b/src/text/memstream.c
index 5dba5f21ed..093a419cf8 100644
--- a/src/text/memstream.c
+++ b/src/text/memstream.c
@@ -164,6 +164,9 @@ int vlc_memstream_vprintf(struct vlc_memstream *ms, const char *fmt,
     len = vsnprintf(NULL, 0, fmt, ap);
     va_end(ap);
 
+    if (len < 0)
+        goto error;
+
     ptr = realloc(ms->ptr, ms->length + len + 1);
     if (ptr == NULL)
         goto error;
-- 
2.11.1