[wrynose][PATCH] util-linux: Fix CVE-2026-3184

[Jaipaul Cheernam <jaipaul.cheernam@est.tech>]

Reference:
[1] https://nvd.nist.gov/vuln/detail/CVE-2026-3184
[2] https://github.com/util-linux/util-linux/commit/8b29aeb081e297e48c4c1ac53d88ae07e1331984

Signed-off-by: Jaipaul Cheernam <jaipaul.cheernam@est.tech>
---
 meta/recipes-core/util-linux/util-linux.inc   |  1 +
 .../util-linux/util-linux/CVE-2026-3184.patch | 61 +++++++++++++++++++
 2 files changed, 62 insertions(+)
 create mode 100644 meta/recipes-core/util-linux/util-linux/CVE-2026-3184.patch

diff --git a/meta/recipes-core/util-linux/util-linux.inc b/meta/recipes-core/util-linux/util-linux.inc
index aec8721ca3..fdc62acc74 100644
--- a/meta/recipes-core/util-linux/util-linux.inc
+++ b/meta/recipes-core/util-linux/util-linux.inc
@@ -20,6 +20,7 @@ SRC_URI = "${KERNELORG_MIRROR}/linux/utils/util-linux/v${MAJOR_VERSION}/util-lin
            file://0001-lsfd-mkfds-foreign-sockets-skip-when-lacking-sock_di.patch \
            file://0001-ts-kill-decode-use-RTMIN-from-kill-L-instead-of-hard.patch \
            file://0001-tests-script-Disable-size-option-test.patch \
+           file://CVE-2026-3184.patch \
            "
 
 SRC_URI[sha256sum] = "f586e35d320ff537aab3ffeca37e9ecd482ccbe013590db4429a414d8aa6a728"
diff --git a/meta/recipes-core/util-linux/util-linux/CVE-2026-3184.patch b/meta/recipes-core/util-linux/util-linux/CVE-2026-3184.patch
new file mode 100644
index 0000000000..6dbfebe4b9
--- /dev/null
+++ b/meta/recipes-core/util-linux/util-linux/CVE-2026-3184.patch
@@ -0,0 +1,61 @@
+From 3fb64ddbffbc9442dca56eb6d4f263d525708b64 Mon Sep 17 00:00:00 2001
+From: Karel Zak <kzak@redhat.com>
+Date: Thu, 19 Feb 2026 12:20:28 +0100
+Subject: [PATCH] login: use original FQDN for PAM_RHOST
+
+When login -h <remotehost> is invoked, init_remote_info() strips the
+local domain suffix from the hostname (FQDN to short name) before
+storing it in cxt->hostname. This truncated value is then used for
+PAM_RHOST, which can bypass pam_access host deny rules that match on
+the FQDN.
+
+Preserve the original -h hostname in a new cmd_hostname field and use
+it for PAM_RHOST, while keeping the truncated hostname for utmp/wtmp
+and logging unchanged.
+
+Note, the real-world impact is low -- login -h is only used by legacy
+telnet/rlogin daemons, and exploitation requires FQDN-specific
+pam_access rules on a system still using these obsolete services.
+
+Reported-by: Asim Viladi Oglu Manizada <manizada@pm.me>
+Signed-off-by: Karel Zak <kzak@redhat.com>
+(cherry picked from commit 8b29aeb081e297e48c4c1ac53d88ae07e1331984)
+
+CVE: CVE-2026-3184
+Upstream-Status: Backport [https://github.com/util-linux/util-linux/commit/8b29aeb081e297e48c4c1ac53d88ae07e1331984]
+
+Signed-off-by: Jaipaul Cheernam <jaipaul.cheernam@est.tech>
+---
+ login-utils/login.c | 5 ++++-
+ 1 file changed, 4 insertions(+), 1 deletion(-)
+
+diff --git a/login-utils/login.c b/login-utils/login.c
+index 321f9d6ce..0c5c805aa 100644
+--- a/login-utils/login.c
++++ b/login-utils/login.c
+@@ -128,6 +128,7 @@ struct login_context {
+ 	char		*thishost;		/* this machine */
+ 	char		*thisdomain;		/* this machine's domain */
+ 	char		*hostname;		/* remote machine */
++	char		*cmd_hostname;		/* remote machine as specified on command line */
+ 	char		hostaddress[16];	/* remote address */
+ 
+ 	pid_t		pid;
+@@ -906,7 +907,7 @@ static pam_handle_t *init_loginpam(struct login_context *cxt)
+ 
+ 	/* hostname & tty are either set to NULL or their correct values,
+ 	 * depending on how much we know. */
+-	rc = pam_set_item(pamh, PAM_RHOST, cxt->hostname);
++	rc = pam_set_item(pamh, PAM_RHOST, cxt->cmd_hostname);
+ 	if (is_pam_failure(rc))
+ 		loginpam_err(pamh, rc);
+ 
+@@ -1249,6 +1250,8 @@ static void init_remote_info(struct login_context *cxt, char *remotehost)
+ 
+ 	get_thishost(cxt, &domain);
+ 
++	cxt->cmd_hostname = xstrdup(remotehost);
++
+ 	if (domain && (p = strchr(remotehost, '.')) &&
+ 	    strcasecmp(p + 1, domain) == 0)
+ 		*p = '\0';