[newlib-cygwin/main] newlib: libc: Fix memory leak in computematchjumps()

[Corinna Vinschen]

https://sourceware.org/git/gitweb.cgi?p=newlib-cygwin.git;h=65f7ab0bb928162f6a6ea60e2803d6b9e5d95e8b

commit 65f7ab0bb928162f6a6ea60e2803d6b9e5d95e8b
Author:     Kuan-Wei Chiu <visitorckw@gmail.com>
AuthorDate: Sat Dec 2 00:13:21 2023 +0800
Commit:     Corinna Vinschen <corinna@vinschen.de>
CommitDate: Fri Dec 1 19:28:55 2023 +0100

    newlib: libc: Fix memory leak in computematchjumps()
    
    In cases where malloc fails for the 'g->matchjump' allocation, the code
    path does not handle the failure gracefully, potentially leading to a
    memory leak. This fix ensures proper cleanup by freeing the allocated
    memory for 'pmatches' before returning.
    
    Signed-off-by: Kuan-Wei Chiu <visitorckw@gmail.com>

Diff:
---
 newlib/libc/posix/regcomp.c | 6 ++++--
 1 file changed, 4 insertions(+), 2 deletions(-)

diff --git a/newlib/libc/posix/regcomp.c b/newlib/libc/posix/regcomp.c
index 002f978cd07c..e71bc005c920 100644
--- a/newlib/libc/posix/regcomp.c
+++ b/newlib/libc/posix/regcomp.c
@@ -2001,8 +2001,10 @@ struct re_guts *g;
 	}
 
 	g->matchjump = (int*) malloc(g->mlen * sizeof(unsigned int));
-	if (g->matchjump == NULL)	/* Not a fatal error */
-		return;
+	if (g->matchjump == NULL) { /* Not a fatal error */
+        free(pmatches);
+        return;
+    }
 
 	/* Set maximum possible jump for each character in the pattern */
 	for (mindex = 0; mindex < g->mlen; mindex++)