From: Karel Zak <kzak@redhat.com>
Date: Tue, 18 Jan 2022 11:30:11 +0000 (+0100)
Subject: lib/strutils: make sure mem2strcpy() buffer is zeroized
X-Git-Tag: v2.38-rc1~51
X-Git-Url: http://git.ipfire.org/?a=commitdiff_plain;h=9c05f4b6bf62a20a64a8e5735c7f3dcf0229e895;p=thirdparty%2Futil-linux.git

lib/strutils: make sure mem2strcpy() buffer is zeroized

Let's make the function robust for work with strings and uninitialized
buffers.

Reported-by: Sean Anderson <seanga2@gmail.com>
Signed-off-by: Karel Zak <kzak@redhat.com>
---

diff --git a/include/strutils.h b/include/strutils.h
index f671b3ba69..8968524a61 100644
--- a/include/strutils.h
+++ b/include/strutils.h
@@ -106,8 +106,8 @@ static inline char *mem2strcpy(char *dest, const void *src, size_t n, size_t nma
 	if (n + 1 > nmax)
 		n = nmax - 1;
 
+	memset(dest, '\0', nmax);
 	memcpy(dest, src, n);
-	dest[nmax-1] = '\0';
 	return dest;
 }