From: Vijay Anusuri <[email protected]>

Pick patch according to [1]

[1] https://security-tracker.debian.org/tracker/CVE-2026-72693
[2] https://nvd.nist.gov/vuln/detail/CVE-2026-72693
[3] https://access.redhat.com/security/cve/cve-2026-72693

Signed-off-by: Vijay Anusuri <[email protected]>
Signed-off-by: Yoann Congal <[email protected]>
---
 .../recipes-core/kbd/kbd/CVE-2026-72693.patch | 155 ++++++++++++++++++
 meta/recipes-core/kbd/kbd_2.9.0.bb            |   1 +
 2 files changed, 156 insertions(+)
 create mode 100644 meta/recipes-core/kbd/kbd/CVE-2026-72693.patch

diff --git a/meta/recipes-core/kbd/kbd/CVE-2026-72693.patch 
b/meta/recipes-core/kbd/kbd/CVE-2026-72693.patch
new file mode 100644
index 00000000000..06b8c195a5a
--- /dev/null
+++ b/meta/recipes-core/kbd/kbd/CVE-2026-72693.patch
@@ -0,0 +1,155 @@
+From 78d5ae119742e87baa7dbe0f5c4107e7533fd698 Mon Sep 17 00:00:00 2001
+From: Alexey Gladkov <[email protected]>
+Date: Tue, 12 May 2026 10:20:50 +0200
+Subject: [PATCH] openvt: make -u process matching more conservative
+
+The -u mode relies on the current VT owner to decide which user should
+be used for the new login session. Make that check stricter by requiring
+a matching process owner and controlling terminal instead of relying on
+the ownership of an inherited file descriptor.
+
+Also reject root as a pre-authenticated target and document the tighter
+behavior in the man page.
+
+Signed-off-by: Alexey Gladkov <[email protected]>
+
+Upstream-Status: Backport 
[https://github.com/legionus/kbd/commit/78d5ae119742e87baa7dbe0f5c4107e7533fd698]
+CVE: CVE-2026-72693
+Signed-off-by: Vijay Anusuri <[email protected]>
+---
+ docs/man/man1/openvt.1 | 10 +++++++
+ src/openvt.c           | 64 +++++++++++++++++++++++++++++++++++++-----
+ 2 files changed, 67 insertions(+), 7 deletions(-)
+
+diff --git a/docs/man/man1/openvt.1 b/docs/man/man1/openvt.1
+index 8f1244f..404e4a0 100644
+--- a/docs/man/man1/openvt.1
++++ b/docs/man/man1/openvt.1
+@@ -36,6 +36,8 @@ will be made the new current VT.
+ \fB\-u\fR, \fB\-\-user\fR
+ Figure out the owner of the current VT, and run login as that user.
+ Suitable to be called by init. Shouldn't be used with \fI\-c\fR or \fI\-l\fR.
++This option refuses to pre-authenticate root and requires a process owned by
++the VT owner whose controlling terminal is the current VT.
+ .TP
+ \fB\-l\fR, \fB\-\-login\fR
+ Make the command a login shell. A \- is prepended to the name of the command
+@@ -64,6 +66,14 @@ If
+ is compiled with a getopt_long() and you wish to set
+ options to the command to be run, then you must supply
+ the end of options \-\- flag before the command.
++.PP
++The
++.B \-u
++option uses
++.BR "login -f"
++and therefore bypasses normal password authentication for the detected user.
++It is intended only for controlled init or keyboard-request configurations.
++Use a normal authenticated login command when authentication is required.
+ .SH EXAMPLES
+ .B openvt
+ can be used to start a shell on the next free VT, by using the command:
+diff --git a/src/openvt.c b/src/openvt.c
+index a94392b..ddd9239 100644
+--- a/src/openvt.c
++++ b/src/openvt.c
+@@ -57,6 +57,51 @@ usage(int rc, const struct kbd_help *options)
+       exit(rc);
+ }
+ 
++static int
++proc_pid_stat(const char *pid, uid_t *uid, dev_t *tty)
++{
++      char filename[NAME_MAX + 12];
++      char line[BUFSIZ];
++      char *lp, *rp;
++      FILE *fp;
++      struct stat st;
++      long tty_nr;
++
++      snprintf(filename, sizeof(filename), "/proc/%s/stat", pid);
++      fp = fopen(filename, "r");
++      if (!fp)
++              return -1;
++
++      if (fstat(fileno(fp), &st)) {
++              fclose(fp);
++              return -1;
++      }
++
++      if (!fgets(line, sizeof(line), fp)) {
++              fclose(fp);
++              return -1;
++      }
++      fclose(fp);
++
++      rp = strrchr(line, ')');
++      if (!rp)
++              return -1;
++
++      /*
++       * /proc/<pid>/stat fields after comm are:
++       * state ppid pgrp session tty_nr ...
++       */
++      if (!rp || sscanf(rp + 1, " %*c %*d %*d %*d %ld", &tty_nr) != 1)
++              return -1;
++
++      if (tty_nr <= 0)
++              return -1;
++
++      *uid = st.st_uid;
++      *tty = (dev_t) tty_nr;
++      return 0;
++}
++
+ /*
+  * Support for Spawn_Console: openvt running from init
+  * added by Joshua Spoerri, Thu Jul 18 21:13:16 EDT 1996
+@@ -88,8 +133,7 @@ authenticate_user(int curvt)
+       DIR *dp;
+       struct dirent *dentp;
+       struct stat buf;
+-      dev_t console_dev;
+-      ino_t console_ino;
++      dev_t console_rdev;
+       uid_t console_uid;
+       char filename[NAME_MAX + 12];
+       struct passwd *pwnam;
+@@ -109,10 +153,12 @@ authenticate_user(int curvt)
+                       kbd_error(EXIT_FAILURE, errsv, "%s", filename);
+               }
+       }
+-      console_dev = buf.st_dev;
+-      console_ino = buf.st_ino;
++      console_rdev = buf.st_rdev;
+       console_uid = buf.st_uid;
+ 
++      if (console_uid == 0)
++              kbd_error(EXIT_FAILURE, 0, _("Refusing to pre-authenticate root 
on current tty."));
++
+       /* get the owner of current tty */
+       if (!(pwnam = getpwuid(console_uid)))
+               kbd_error(EXIT_FAILURE, errno, "getpwuid");
+@@ -120,12 +166,16 @@ authenticate_user(int curvt)
+       /* check to make sure that user has a process on that tty */
+       /* this will fail for example when X is running on the tty */
+       while ((dentp = readdir(dp))) {
+-              sprintf(filename, "/proc/%s/fd/0", dentp->d_name);
++              uid_t proc_uid;
++              dev_t proc_tty;
++
++              if (dentp->d_name[0] < '0' || dentp->d_name[0] > '9')
++                      continue;
+ 
+-              if (stat(filename, &buf))
++              if (proc_pid_stat(dentp->d_name, &proc_uid, &proc_tty) < 0)
+                       continue;
+ 
+-              if (buf.st_dev == console_dev && buf.st_ino == console_ino && 
buf.st_uid == console_uid)
++              if (proc_uid == console_uid && proc_tty == console_rdev)
+                       goto got_a_process;
+       }
+ 
+-- 
+2.43.0
+
diff --git a/meta/recipes-core/kbd/kbd_2.9.0.bb 
b/meta/recipes-core/kbd/kbd_2.9.0.bb
index 79b011e529d..06341ba8c04 100644
--- a/meta/recipes-core/kbd/kbd_2.9.0.bb
+++ b/meta/recipes-core/kbd/kbd_2.9.0.bb
@@ -26,6 +26,7 @@ RCONFLICTS:${PN} = "console-tools"
 SRC_URI = "${KERNELORG_MIRROR}/linux/utils/${BPN}/${BP}.tar.xz \
            file://0001-Preserve-only-necessary-metadata-during-install.patch \
            file://0001-libkbdfile-Fix-problem-with-undeclared-sym_gzopen.patch 
\
+           file://CVE-2026-72693.patch \
            "
 
 SRC_URI[sha256sum] = 
"fb3197f17a99eb44d22a3a1a71f755f9622dd963e66acfdea1a45120951b02ed"
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