From bb5ac84d79ac3aef606a4a9eeaafef94a1f199be Mon Sep 17 00:00:00 2001
From: Balint Reczey <balint.reczey@canonical.com>
Date: Wed, 24 Apr 2019 16:35:32 +0200
Subject: [PATCH 1/2] Move verify_vc_kbmode() to terminal-util.c as
 vt_verify_kbmode()

---
 src/basic/terminal-util.c     | 17 +++++++++++++++++
 src/basic/terminal-util.h     |  1 +
 src/vconsole/vconsole-setup.c | 23 +++--------------------
 3 files changed, 21 insertions(+), 20 deletions(-)

diff --git a/src/basic/terminal-util.c b/src/basic/terminal-util.c
index b692c52e59..3a9c85e5a0 100644
--- a/src/basic/terminal-util.c
+++ b/src/basic/terminal-util.c
@@ -1249,6 +1249,23 @@ int vt_default_utf8(void) {
         return parse_boolean(b);
 }
 
+int vt_verify_kbmode(int fd) {
+        int curr_mode;
+
+        /*
+         * Make sure we only adjust consoles in K_XLATE or K_UNICODE mode.
+         * Otherwise we would (likely) interfere with X11's processing of the
+         * key events.
+         *
+         * http://lists.freedesktop.org/archives/systemd-devel/2013-February/008573.html
+         */
+
+        if (ioctl(fd, KDGKBMODE, &curr_mode) < 0)
+                return -errno;
+
+        return IN_SET(curr_mode, K_XLATE, K_UNICODE) ? 0 : -EBUSY;
+}
+
 int vt_reset_keyboard(int fd) {
         int kb;
 
diff --git a/src/basic/terminal-util.h b/src/basic/terminal-util.h
index c885e0a2d1..b32528f1d0 100644
--- a/src/basic/terminal-util.h
+++ b/src/basic/terminal-util.h
@@ -155,6 +155,7 @@ int openpt_in_namespace(pid_t pid, int flags);
 int open_terminal_in_namespace(pid_t pid, const char *name, int mode);
 
 int vt_default_utf8(void);
+int vt_verify_kbmode(int fd);
 int vt_reset_keyboard(int fd);
 int vt_restore(int fd);
 int vt_release(int fd, bool restore_vt);
diff --git a/src/vconsole/vconsole-setup.c b/src/vconsole/vconsole-setup.c
index 67dc2e49f9..1feb8d9370 100644
--- a/src/vconsole/vconsole-setup.c
+++ b/src/vconsole/vconsole-setup.c
@@ -70,23 +70,6 @@ static int verify_vc_allocation_byfd(int fd) {
         return verify_vc_allocation(vcs.v_active);
 }
 
-static int verify_vc_kbmode(int fd) {
-        int curr_mode;
-
-        /*
-         * Make sure we only adjust consoles in K_XLATE or K_UNICODE mode.
-         * Otherwise we would (likely) interfere with X11's processing of the
-         * key events.
-         *
-         * http://lists.freedesktop.org/archives/systemd-devel/2013-February/008573.html
-         */
-
-        if (ioctl(fd, KDGKBMODE, &curr_mode) < 0)
-                return -errno;
-
-        return IN_SET(curr_mode, K_XLATE, K_UNICODE) ? 0 : -EBUSY;
-}
-
 static int toggle_utf8(const char *name, int fd, bool utf8) {
         int r;
         struct termios tc = {};
@@ -290,7 +273,7 @@ static void setup_remaining_vcs(int src_fd, unsigned src_idx, bool utf8) {
                         continue;
                 }
 
-                if (verify_vc_kbmode(fd_d) < 0)
+                if (vt_verify_kbmode(fd_d) < 0)
                         continue;
 
                 toggle_utf8(ttyname, fd_d, utf8);
@@ -365,7 +348,7 @@ static int find_source_vc(char **ret_path, unsigned *ret_idx) {
                                 err = -fd;
                         continue;
                 }
-                r = verify_vc_kbmode(fd);
+                r = vt_verify_kbmode(fd);
                 if (r < 0) {
                         if (!err)
                                 err = -r;
@@ -398,7 +381,7 @@ static int verify_source_vc(char **ret_path, const char *src_vc) {
         if (r < 0)
                 return log_error_errno(r, "Virtual console %s is not allocated: %m", src_vc);
 
-        r = verify_vc_kbmode(fd);
+        r = vt_verify_kbmode(fd);
         if (r < 0)
                 return log_error_errno(r, "Virtual console %s is not in K_XLATE or K_UNICODE: %m", src_vc);
 

From 13a43c73d8cbac4b65472de04bb88ea1bacdeb89 Mon Sep 17 00:00:00 2001
From: Balint Reczey <balint.reczey@canonical.com>
Date: Wed, 24 Apr 2019 17:24:02 +0200
Subject: [PATCH 2/2] Add check to switch VTs only between K_XLATE or K_UNICODE

Switching to K_UNICODE from other than L_XLATE can make the keyboard
unusable and possibly leak keypresses from X.

BugLink: https://launchpad.net/bugs/1803993
---
 src/basic/terminal-util.c     | 9 ++++++++-
 src/vconsole/vconsole-setup.c | 7 +++++++
 2 files changed, 15 insertions(+), 1 deletion(-)

diff --git a/src/basic/terminal-util.c b/src/basic/terminal-util.c
index 3a9c85e5a0..0b71220ec4 100644
--- a/src/basic/terminal-util.c
+++ b/src/basic/terminal-util.c
@@ -1267,11 +1267,18 @@ int vt_verify_kbmode(int fd) {
 }
 
 int vt_reset_keyboard(int fd) {
-        int kb;
+        int kb, r;
 
         /* If we can't read the default, then default to unicode. It's 2017 after all. */
         kb = vt_default_utf8() != 0 ? K_UNICODE : K_XLATE;
 
+        r = vt_verify_kbmode(fd);
+        if (r == -EBUSY) {
+                log_debug_errno(r, "Keyboard is not in XLATE or UNICODE mode, not resetting: %m");
+                return 0;
+        } else if (r < 0)
+                return r;
+
         if (ioctl(fd, KDSKBMODE, kb) < 0)
                 return -errno;
 
diff --git a/src/vconsole/vconsole-setup.c b/src/vconsole/vconsole-setup.c
index 1feb8d9370..140e0badd2 100644
--- a/src/vconsole/vconsole-setup.c
+++ b/src/vconsole/vconsole-setup.c
@@ -76,6 +76,13 @@ static int toggle_utf8(const char *name, int fd, bool utf8) {
 
         assert(name);
 
+        r = vt_verify_kbmode(fd);
+        if (r == -EBUSY) {
+                log_warning_errno(r, "Virtual console %s is not in K_XLATE or K_UNICODE: %m", name);
+                return 0;
+        } else if (r < 0)
+                return log_warning_errno(r, "Failed to verify kbdmode on %s: %m", name);
+
         r = ioctl(fd, KDSKBMODE, utf8 ? K_UNICODE : K_XLATE);
         if (r < 0)
                 return log_warning_errno(errno, "Failed to %s UTF-8 kbdmode on %s: %m", enable_disable(utf8), name);