Fix documentation of X509_VERIFY_PARAM_add0_policy()

The function was incorrectly documented as enabling policy checking.

Fixes: CVE-2023-0466
Reviewed-by: NMatt Caswell <matt@openssl.org>
Reviewed-by: NPaul Dale <pauli@openssl.org>
(Merged from https://github.com/openssl/openssl/pull/20564)
Signed-off-by: Ncode4lala <fengziteng2@huawei.com>

CHANGES

@@ -8,6 +8,10 @@
  release branch.
 
  Changes between 1.1.1s and 1.1.1t [xx XXX xxxx]
+  *) Corrected documentation of X509_VERIFY_PARAM_add0_policy() to mention
+     that it does not enable policy checking. Thanks to
+     David Benjamin for discovering this issue. (CVE-2023-0466)
+     [Tomas Mraz]
 
   *) Fixed a type confusion vulnerability relating to X.400 address processing
      inside an X.509 GeneralName. X.400 addresses were parsed as an ASN1_STRING

NEWS

@@ -4,6 +4,7 @@
 
   This file gives a brief overview of the major changes between each OpenSSL
   release. For more details please read the CHANGES file.
+      o Fixed documentation of X509_VERIFY_PARAM_add0_policy() (CVE-2023-0466)
 
   Major changes between OpenSSL 1.1.1m and OpenSSL 1.1.1n [15 Mar 2022]
 

doc/man3/X509_VERIFY_PARAM_set_flags.pod

@@ -92,8 +92,9 @@ B<trust>.
 X509_VERIFY_PARAM_set_time() sets the verification time in B<param> to
 B<t>. Normally the current time is used.
 
-X509_VERIFY_PARAM_add0_policy() enables policy checking (it is disabled
-by default) and adds B<policy> to the acceptable policy set.
+X509_VERIFY_PARAM_add0_policy() adds B<policy> to the acceptable policy set.
+Contrary to preexisting documentation of this function it does not enable
+policy checking.
 
 X509_VERIFY_PARAM_set1_policies() enables policy checking (it is disabled
 by default) and sets the acceptable policy set to B<policies>. Any existing
@@ -377,6 +378,10 @@ and has no effect.
 
 The X509_VERIFY_PARAM_get_hostflags() function was added in OpenSSL 1.1.0i.
 
+The function X509_VERIFY_PARAM_add0_policy() was historically documented as
+enabling policy checking however the implementation has never done this.
+The documentation was changed to align with the implementation.
+
 =head1 COPYRIGHT
 
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