openssh: fix CVE-2025-61985

ssh in OpenSSH before 10.1 allows the '\0' character in an ssh:// URI,
potentially leading to code execution when a ProxyCommand is used.

Reference:
https://nvd.nist.gov/vuln/detail/CVE-2025-61985

Upstream patch:
43b3bff47b

(From OE-Core rev: 52d925423b826383d12a97b834475ab5699fd492)

Signed-off-by: David Nyström <david.nystrom@est.tech>
Signed-off-by: Steve Sakoman <steve@sakoman.com>

meta/recipes-connectivity/openssh/openssh/CVE-2025-61985.patch

@@ -0,0 +1,47 @@
+From 54928cb9eaa7143ff17f463efa7ed3109afdbf30 Mon Sep 17 00:00:00 2001
+From: "djm@openbsd.org" <djm@openbsd.org>
+Date: Thu, 4 Sep 2025 00:30:06 +0000
+Subject: [PATCH] upstream: don't allow \0 characters in url-encoded strings.
+MIME-Version: 1.0
+Content-Type: text/plain; charset=UTF-8
+Content-Transfer-Encoding: 8bit
+
+Suggested by David Leadbeater, ok deraadt@
+
+OpenBSD-Commit-ID: c92196cef0f970ceabc1e8007a80b01e9b7cd49c
+
+Upstream-Status: Backport [Upstream commit https://github.com/openssh/openssh-portable/commit/43b3bff47bb029f2299bacb6a36057981b39fdb0]
+CVE: CVE-2025-61985
+Signed-off-by: David Nyström <david.nystrom@est.tech>
+---
+ misc.c | 5 +++--
+ 1 file changed, 3 insertions(+), 2 deletions(-)
+
+diff --git a/misc.c b/misc.c
+index 3db2e4d0b..cac246b63 100644
+--- a/misc.c
++++ b/misc.c
+@@ -955,7 +955,7 @@ urldecode(const char *src)
+ 	size_t srclen;
+ 
+ 	if ((srclen = strlen(src)) >= SIZE_MAX)
+-		fatal_f("input too large");
++		return NULL;
+ 	ret = xmalloc(srclen + 1);
+ 	for (dst = ret; *src != '\0'; src++) {
+ 		switch (*src) {
+@@ -963,9 +963,10 @@ urldecode(const char *src)
+ 			*dst++ = ' ';
+ 			break;
+ 		case '%':
++			/* note: don't allow \0 characters */
+ 			if (!isxdigit((unsigned char)src[1]) ||
+ 			    !isxdigit((unsigned char)src[2]) ||
+-			    (ch = hexchar(src + 1)) == -1) {
++			    (ch = hexchar(src + 1)) == -1 || ch == 0) {
+ 				free(ret);
+ 				return NULL;
+ 			}
+-- 
+2.44.1
+

meta/recipes-connectivity/openssh/openssh_9.6p1.bb

@@ -32,6 +32,7 @@ SRC_URI = "http://ftp.openbsd.org/pub/OpenBSD/OpenSSH/portable/openssh-${PV}.tar
            file://CVE-2025-26466.patch \
            file://CVE-2025-26465.patch \
            file://CVE-2025-32728.patch \
+           file://CVE-2025-61985.patch \
            "
 SRC_URI[sha256sum] = "910211c07255a8c5ad654391b40ee59800710dd8119dd5362de09385aa7a777c"