commit 9b97c3a72a0ef1b66e0326d180fa0b29fc9c2094
Author: l30004689 <liuqirun@huawei.com>
Date:   Fri Jun 11 03:01:43 2021 -0400

    [Backport]Fix potential memory corruption with negative memmove() size
    
    Offering: GaussDB Kernel
    CVE: CVE-2021-3520
    Reference: https://github.com/lz4/lz4/commit/8301a21773ef61656225e264f4f06ae14462bca7
    Signed-off-by: liuqirun liuqirun@huawei.com

diff --git a/lib/lz4.c b/lib/lz4.c
index 9808d70..805388d 100644
--- a/lib/lz4.c
+++ b/lib/lz4.c
@@ -1665,7 +1665,7 @@ LZ4_decompress_generic(
                  const size_t dictSize         /* note : = 0 if noDict */
                  )
 {
-    if (src == NULL) { return -1; }
+    if ((src == NULL) || (outputSize < 0)) { return -1; }
 
     {   const BYTE* ip = (const BYTE*) src;
         const BYTE* const iend = ip + srcSize;