zlib: Remove incorrect ZLIB_VERSION

Get rid of zlib version which is not correct because of U-Boot related
changes and various CVE backports.

The change in inspired by Linux kernel commit 4f3865fb57a0 ("[PATCH]
zlib_inflate: Upgrade library code to a recent version") which described
ZLIB_VERSION removal as

"This patch also removes ZLIB_VERSION as it no longer has a correct value.
We don't need version checks anyway as the kernel's module handling will
take care of that for us.  This removal is also more in keeping with the
zlib author's wishes (http://www.zlib.net/zlib_faq.html#faq24) and I've
added something to the zlib.h header to note its a modified version."

Author describes wish to follow this guidance at
https://www.zlib.net/zlib_faq.html#faq24:
"The license says that altered source versions must be "plainly marked". So
what exactly do I need to do to meet that requirement?

You need to change the ZLIB_VERSION and ZLIB_VERNUM #defines in zlib.h. In
particular, the final version number needs to be changed to f, and an
identification string should be appended to ZLIB_VERSION. Version numbers
x.x.x.f are reserved for modifications to zlib by others than the zlib
maintainers. For example, if the version of the base zlib you are altering
is 1.2.3.4, then in zlib.h you should change ZLIB_VERNUM to 0x123f, and
ZLIB_VERSION to something like 1.2.3.f-zachary-mods-v3. You can also update
the version strings in deflate.c and inftrees.c."

But U-Boot is not exact version that's why following the same style which
has been used by Linux kernel where ZLIB_VERSION is completely removed.

Signed-off-by: Michal Simek <michal.simek@amd.com>

4 files changed, 7 insertions, 18 deletions

diff --git a/lib/gzip.c b/lib/gzip.c
index 5d9c195..a9a3df5 100644
--- a/lib/gzip.c
+++ b/lib/gzip.c
@@ -67,7 +67,7 @@ int zzip(void *dst, unsigned long *lenp, unsigned char *src,
 
 	r = deflateInit2_(&s, Z_BEST_SPEED, Z_DEFLATED,	window,
 			DEF_MEM_LEVEL, Z_DEFAULT_STRATEGY,
-			ZLIB_VERSION, sizeof(z_stream));
+			sizeof(z_stream));
 	if (r != Z_OK) {
 		printf ("Error: deflateInit2_() returned %d\n", r);
 		return -1;
diff --git a/lib/zlib/deflate.c b/lib/zlib/deflate.c
index 4549f4d..7e1ed4f 100644
--- a/lib/zlib/deflate.c
+++ b/lib/zlib/deflate.c
@@ -196,37 +196,30 @@ struct static_tree_desc_s {int dummy;}; /* for buggy compilers */
     zmemzero((Bytef *)s->head, (unsigned)(s->hash_size-1)*sizeof(*s->head));
 
 /* ========================================================================= */
-int ZEXPORT deflateInit_(strm, level, version, stream_size)
+int ZEXPORT deflateInit_(strm, level, stream_size)
     z_streamp strm;
     int level;
-    const char *version;
     int stream_size;
 {
     return deflateInit2_(strm, level, Z_DEFLATED, MAX_WBITS, DEF_MEM_LEVEL,
-                         Z_DEFAULT_STRATEGY, version, stream_size);
+                         Z_DEFAULT_STRATEGY, stream_size);
     /* To do: ignore strm->next_in if we use it as window */
 }
 
 /* ========================================================================= */
 int ZEXPORT deflateInit2_(strm, level, method, windowBits, memLevel, strategy,
-                  version, stream_size)
+                  stream_size)
     z_streamp strm;
     int  level;
     int  method;
     int  windowBits;
     int  memLevel;
     int  strategy;
-    const char *version;
     int stream_size;
 {
     deflate_state *s;
     int wrap = 1;
-    static const char my_version[] = ZLIB_VERSION;
 
-    if (version == Z_NULL || version[0] != my_version[0] ||
-        stream_size != sizeof(z_stream)) {
-        return Z_VERSION_ERROR;
-    }
     if (strm == Z_NULL) return Z_STREAM_ERROR;
 
     strm->msg = Z_NULL;
diff --git a/lib/zlib/inflate.c b/lib/zlib/inflate.c
index 79c9e99..f7e81fc 100644
--- a/lib/zlib/inflate.c
+++ b/lib/zlib/inflate.c
@@ -30,14 +30,11 @@ int ZEXPORT inflateReset(z_streamp strm)
     return Z_OK;
 }
 
-int ZEXPORT inflateInit2_(z_streamp strm, int windowBits, const char *version,
+int ZEXPORT inflateInit2_(z_streamp strm, int windowBits,
 			  int stream_size)
 {
     struct inflate_state FAR *state;
 
-    if (version == Z_NULL || version[0] != ZLIB_VERSION[0] ||
-        stream_size != (int)(sizeof(z_stream)))
-        return Z_VERSION_ERROR;
     if (strm == Z_NULL) return Z_STREAM_ERROR;
     strm->msg = Z_NULL;                 /* in case we return an error */
     if (strm->zalloc == (alloc_func)0) {
@@ -70,9 +67,9 @@ int ZEXPORT inflateInit2_(z_streamp strm, int windowBits, const char *version,
     return inflateReset(strm);
 }
 
-int ZEXPORT inflateInit_(z_streamp strm, const char *version, int stream_size)
+int ZEXPORT inflateInit_(z_streamp strm, int stream_size)
 {
-    return inflateInit2_(strm, DEF_WBITS, version, stream_size);
+    return inflateInit2_(strm, DEF_WBITS, stream_size);
 }
 
 local void fixedtables(struct inflate_state FAR *state)
diff --git a/lib/zlib/zutil.c b/lib/zlib/zutil.c
index 609aac5..ec21b45 100644
--- a/lib/zlib/zutil.c
+++ b/lib/zlib/zutil.c
@@ -21,7 +21,6 @@ const char * const z_errmsg[10] = {
 "data error",          /* Z_DATA_ERROR    (-3) */
 "insufficient memory", /* Z_MEM_ERROR     (-4) */
 "buffer error",        /* Z_BUF_ERROR     (-5) */
-"incompatible version",/* Z_VERSION_ERROR (-6) */
 ""};
 
 #ifdef DEBUG