From: Adenilson Cavalcanti <cavalcantii@chromium.org>
Date: Wed, 7 Aug 2024 00:16:28 +0000 (-0700)
Subject: [zstd][leak] Avoid memory leak on early return of ZSTD_generateSequence
X-Git-Tag: v1.5.7^2~94^2
X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=refs%2Fpull%2F4115%2Fhead;p=thirdparty%2Fzstd.git

[zstd][leak] Avoid memory leak on early return of ZSTD_generateSequence

Sanity checks on a few of the context parameters (i.e. workers and block size)
may prompt an early return on ZSTD_generateSequences.

Allocating the destination buffer past those return points avoids a potential
memory leak.

This patch should fix issue #4112.
---

diff --git a/lib/compress/zstd_compress.c b/lib/compress/zstd_compress.c
index 18f929bbe..aad25049d 100644
--- a/lib/compress/zstd_compress.c
+++ b/lib/compress/zstd_compress.c
@@ -3458,7 +3458,7 @@ size_t ZSTD_generateSequences(ZSTD_CCtx* zc, ZSTD_Sequence* outSeqs,
                               size_t outSeqsSize, const void* src, size_t srcSize)
 {
     const size_t dstCapacity = ZSTD_compressBound(srcSize);
-    void* dst = ZSTD_customMalloc(dstCapacity, ZSTD_defaultCMem);
+    void* dst; /* Make C90 happy. */
     SeqCollector seqCollector;
     {
         int targetCBlockSize;
@@ -3471,6 +3471,7 @@ size_t ZSTD_generateSequences(ZSTD_CCtx* zc, ZSTD_Sequence* outSeqs,
         RETURN_ERROR_IF(nbWorkers != 0, parameter_unsupported, "nbWorkers != 0");
     }
 
+    dst = ZSTD_customMalloc(dstCapacity, ZSTD_defaultCMem);
     RETURN_ERROR_IF(dst == NULL, memory_allocation, "NULL pointer!");
 
     seqCollector.collectSequences = 1;