From: Viktor Szakats <commit@vsz.me>
Date: Tue, 23 Dec 2025 11:03:10 +0000 (+0100)
Subject: lib547, 555: fix off-by-one null-terminator in read callback
X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=66aec526fcdb91bfabca7be638eff13d53b51a8a;p=thirdparty%2Fcurl.git

lib547, 555: fix off-by-one null-terminator in read callback

`strcpy()` wrote an unnecessary null-terminator past the available read
buffer.

test551 was also affected because it reuses lib547.

Cherry-picked from #20076
Closes #20082
---

diff --git a/tests/libtest/lib547.c b/tests/libtest/lib547.c
index cafb845f70..6611bdeaec 100644
--- a/tests/libtest/lib547.c
+++ b/tests/libtest/lib547.c
@@ -44,7 +44,7 @@ static size_t t547_read_cb(char *ptr, size_t size, size_t nmemb, void *clientp)
 
   if(size * nmemb >= T547_DATALEN) {
     curl_mfprintf(stderr, "READ!\n");
-    strcpy(ptr, t547_uploadthis);
+    memcpy(ptr, t547_uploadthis, T547_DATALEN);
     return T547_DATALEN;
   }
   curl_mfprintf(stderr, "READ NOT FINE!\n");
diff --git a/tests/libtest/lib555.c b/tests/libtest/lib555.c
index b0573b7f1a..883b73b5bb 100644
--- a/tests/libtest/lib555.c
+++ b/tests/libtest/lib555.c
@@ -48,7 +48,7 @@ static size_t t555_read_cb(char *ptr, size_t size, size_t nmemb, void *clientp)
 
   if(size * nmemb >= T555_DATALEN) {
     curl_mfprintf(stderr, "READ!\n");
-    strcpy(ptr, t555_uploadthis);
+    memcpy(ptr, t555_uploadthis, T555_DATALEN);
     return T555_DATALEN;
   }
   curl_mfprintf(stderr, "READ NOT FINE!\n");