diff --git a/ChangeLog b/ChangeLog
index c59df38c2..0063cdf04 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,3 +1,9 @@
+2011-12-15  Vladimir Serbinenko  <phcoder@gmail.com>
+
+	* grub-core/lib/reed_solomon.c (decode_block): Allocate on heap and not
+	stack.
+	(encode_block): Likewise.
+
 2011-12-15  Vladimir Serbinenko  <phcoder@gmail.com>
 
 	* grub-core/boot/i386/pc/startup_raw.S: Clear direction flag for
diff --git a/grub-core/lib/reed_solomon.c b/grub-core/lib/reed_solomon.c
index fc5443c28..3d8bb9e1f 100644
--- a/grub-core/lib/reed_solomon.c
+++ b/grub-core/lib/reed_solomon.c
@@ -390,12 +390,19 @@ decode_block (gf_single_t *ptr, grub_size_t s,
     {
       grub_size_t ds = (s + SECTOR_SIZE - 1 - i) / SECTOR_SIZE;
       grub_size_t rr = (rs + SECTOR_SIZE - 1 - i) / SECTOR_SIZE;
-      gf_single_t m[ds + rr];
+      gf_single_t *m;
 
       /* Nothing to do.  */
       if (!ds || !rr)
 	continue;
 
+#ifndef STANDALONE
+      m = xmalloc (ds + rr);
+#else
+      m = (gf_single_t *) scratch;
+      scratch += ds + rr;
+#endif
+
       for (j = 0; j < (int) ds; j++)
 	m[j] = ptr[SECTOR_SIZE * j + i];
       for (j = 0; j < (int) rr; j++)
@@ -405,6 +412,12 @@ decode_block (gf_single_t *ptr, grub_size_t s,
 
       for (j = 0; j < (int) ds; j++)
 	ptr[SECTOR_SIZE * j + i] = m[j];
+
+#ifndef STANDALONE
+      free (m);
+#else
+      scratch -= ds + rr;
+#endif
     }
 }
 
@@ -418,12 +431,18 @@ encode_block (gf_single_t *ptr, grub_size_t s,
     {
       grub_size_t ds = (s + SECTOR_SIZE - 1 - i) / SECTOR_SIZE;
       grub_size_t rr = (rs + SECTOR_SIZE - 1 - i) / SECTOR_SIZE;
-      gf_single_t m[ds + rr];
+      gf_single_t *m;
+
+      if (!ds || !rr)
+	continue;
+
+      m = xmalloc (ds + rr);
       for (j = 0; j < ds; j++)
 	m[j] = ptr[SECTOR_SIZE * j + i];
       rs_encode (m, ds, rr);
       for (j = 0; j < rr; j++)      
 	rptr[SECTOR_SIZE * j + i] = m[j + ds];
+      free (m);
     }
 }
 #endif