X-Git-Url: http://erislabs.net/gitweb/?a=blobdiff_plain;f=lib%2Fargp-fmtstream.c;h=c88c3db2147136dbb8931f0b50dc1953b050b940;hb=1caf9135115db922238f1a9e9e52759e251454a3;hp=c6d79a56fcacdb14e3df67ae4ea996622f177576;hpb=a82fdff58064e24994117ed668ae13362253be46;p=gnulib.git

diff --git a/lib/argp-fmtstream.c b/lib/argp-fmtstream.c
index c6d79a56f..c88c3db21 100644
--- a/lib/argp-fmtstream.c
+++ b/lib/argp-fmtstream.c
@@ -384,10 +384,11 @@ __argp_fmtstream_ensure (struct argp_fmtstream *fs, size_t amount)
       if ((size_t) (fs->end - fs->buf) < amount)
 	/* Gotta grow the buffer.  */
 	{
-	  size_t new_size = fs->end - fs->buf + amount;
-	  char *new_buf = realloc (fs->buf, new_size);
+	  size_t old_size = fs->end - fs->buf;
+	  size_t new_size = old_size + amount;
+	  char *new_buf;
 
-	  if (! new_buf)
+	  if (new_size < old_size || ! (new_buf = realloc (fs->buf, new_size)))
 	    {
 	      __set_errno (ENOMEM);
 	      return 0;