When you replace an element in a sorted array with something

arbitrarily different, the array is in general no longer sorted.

This commit copies a small hidden bugfix from the OpenSSL commit
https://github.com/openssl/openssl/commit/fbb7b33b
the rest of which is merely cosmetics.

I discovered the bug independently while documenting sk_find(3).

Keep the library's idea of when an empty stack or a one-element stack
is sorted and when it is not bug-compatible with OpenSSL, even though
in fact, empty and one-element stacks are of course always sorted.

OK beck@

2 files changed, 6 insertions, 13 deletions

diff --git a/src/lib/libcrypto/man/OPENSSL_sk_new.3 b/src/lib/libcrypto/man/OPENSSL_sk_new.3
index 748411bf15..47b19cb4e8 100644
--- a/src/lib/libcrypto/man/OPENSSL_sk_new.3
+++ b/src/lib/libcrypto/man/OPENSSL_sk_new.3
@@ -1,4 +1,4 @@
-.\" $OpenBSD: OPENSSL_sk_new.3,v 1.8 2018/03/27 17:35:50 schwarze Exp $
+.\" $OpenBSD: OPENSSL_sk_new.3,v 1.9 2018/04/01 00:36:28 schwarze Exp $
 .\"
 .\" Copyright (c) 2018 Ingo Schwarze <schwarze@openbsd.org>
 .\"
@@ -14,7 +14,7 @@
 .\" ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
 .\" OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
 .\"
-.Dd $Mdocdate: March 27 2018 $
+.Dd $Mdocdate: April 1 2018 $
 .Dt OPENSSL_SK_NEW 3
 .Os
 .Sh NAME
@@ -279,8 +279,9 @@ or
 successfuly calling
 .Fn sk_push ,
 .Fn sk_unshift ,
-or
 .Fn sk_insert ,
+or
+.Fn sk_set ,
 or changing the comparison function sets the state to unsorted.
 If a comparison function is installed, calling
 .Fn sk_sort ,
@@ -564,15 +565,6 @@ first appeared in OpenSSL 0.9.7e and has been available since
 first appeared in OpenSSL 0.9.8 and has been available since
 .Ox 4.5 .
 .Sh BUGS
-.Fn sk_set
-does not set the state of the
-.Fa stack
-to unsorted.
-This can cause wrong results from subsequent
-.Fn sk_find
-and
-.Fn sk_find_ex .
-.Pp
 Even if a comparison function is installed, empty stacks and
 stacks containing a single pointer are sometimes considered
 sorted and sometimes considered unsorted.
diff --git a/src/lib/libcrypto/stack/stack.c b/src/lib/libcrypto/stack/stack.c
index d941f9e6fb..b76a0d7271 100644
--- a/src/lib/libcrypto/stack/stack.c
+++ b/src/lib/libcrypto/stack/stack.c
@@ -1,4 +1,4 @@
-/* $OpenBSD: stack.c,v 1.19 2015/02/07 13:19:15 doug Exp $ */
+/* $OpenBSD: stack.c,v 1.20 2018/04/01 00:36:28 schwarze Exp $ */
 /* Copyright (C) 1995-1998 Eric Young (eay@cryptsoft.com)
  * All rights reserved.
  *
@@ -312,6 +312,7 @@ sk_set(_STACK *st, int i, void *value)
 {
         if (!st || (i < 0) || (i >= st->num))
                 return NULL;
+        st->sorted = 0;
         return (st->data[i] = value);
 }