# \[PATCH\] Fix potential overlap dest buffer

- From: Nigel Croxon \<hidden\>
- Date: 2021-08-17 13:14:54 
- List: linux-raid
- Page: https://ratatoskr.run/linux-raid/2021/08/6640571
- Thread: https://ratatoskr.run/linux-raid/2021/08/6640571/t.md

```text
To meet requirements of Common Criteria certification vulnerablility
assessment. Static code analysis has been run and found the following
error.  Overlapping_buffer: The source buffer potentially overlaps
with the destination buffer, which results in undefined
behavior for "memcpy".

The change is to use memmove instead of memcpy.

Signed-off-by: Nigel Croxon <redacted>
---
 sha1.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/sha1.c b/sha1.c
index 11be7045..89b32f46 100644
--- a/sha1.c
+++ b/sha1.c
@@ -258,7 +258,7 @@ sha1_process_bytes (const void *buffer, size_t len, struct sha1_ctx *ctx)
 	{
 	  sha1_process_block (ctx->buffer, 64, ctx);
 	  left_over -= 64;
-	  memcpy (ctx->buffer, &ctx->buffer[16], left_over);
+	  memmove (ctx->buffer, &ctx->buffer[16], left_over);
 	}
       ctx->buflen = left_over;
     }
-- 
2.29.2

```