aws: Allocate S3_KEY_SIZE +1 instead of S3_KEY_SIZE for allocating buffer for s3 key

This is because macOS's strlen complains buffer overflow due to
exceeding length of allocated buffers. To prevent this issue,
we need to allocate an adittional +1 length of char type of buffer.

Signed-off-by: Hiroshi Hatake <[email protected]>

Author: cosmo0920

src/aws/flb_aws_util.c

@@ -908,8 +908,8 @@ flb_sds_t flb_get_s3_key(const char *format, time_t time, const char *tag,
     flb_sds_destroy(tmp);
     tmp = NULL;
 
-    /* A string no longer than S3_KEY_SIZE is created to store the formatted timestamp. */
-    key = flb_calloc(1, S3_KEY_SIZE * sizeof(char));
+    /* A string no longer than S3_KEY_SIZE + 1 is created to store the formatted timestamp. */
+    key = flb_calloc(1, (S3_KEY_SIZE + 1) * sizeof(char));
     if (!key) {
         goto error;
     }