From 70e8fb8d66703e5751ac4d3ad8efbfb0ffd8f29a Mon Sep 17 00:00:00 2001
From: Jiri Slaby <jslaby@suse.cz>
Date: Apr 20 2023 11:00:14 +0000
Subject: fbcon: Fix error paths in set_con2fb_map (bsc#1012628).


---

diff --git a/patches.kernel.org/6.2.12-026-fbcon-Fix-error-paths-in-set_con2fb_map.patch b/patches.kernel.org/6.2.12-026-fbcon-Fix-error-paths-in-set_con2fb_map.patch
new file mode 100644
index 0000000..b95b66a
--- /dev/null
+++ b/patches.kernel.org/6.2.12-026-fbcon-Fix-error-paths-in-set_con2fb_map.patch
@@ -0,0 +1,101 @@
+From: Daniel Vetter <daniel.vetter@ffwll.ch>
+Date: Wed, 12 Apr 2023 17:23:49 +0200
+Subject: [PATCH] fbcon: Fix error paths in set_con2fb_map
+References: bsc#1012628
+Patch-mainline: 6.2.12
+Git-commit: edf79dd2172233452ff142dcc98b19d955fc8974
+
+commit edf79dd2172233452ff142dcc98b19d955fc8974 upstream.
+
+This is a regressoin introduced in b07db3958485 ("fbcon: Ditch error
+handling for con2fb_release_oldinfo"). I failed to realize what the if
+(!err) checks. The mentioned commit was dropping the
+con2fb_release_oldinfo() return value but the if (!err) was also
+checking whether the con2fb_acquire_newinfo() function call above
+failed or not.
+
+Fix this with an early return statement.
+
+Note that there's still a difference compared to the orginal state of
+the code, the below lines are now also skipped on error:
+
+	if (!search_fb_in_map(info_idx))
+		info_idx = newidx;
+
+These are only needed when we've actually thrown out an old fb_info
+from the console mappings, which only happens later on.
+
+Also move the fbcon_add_cursor_work() call into the same if block,
+it's all protected by console_lock so doesn't matter when we set up
+the blinking cursor delayed work anyway. This further simplifies the
+control flow and allows us to ditch the found local variable.
+
+v2: Clarify commit message (Javier)
+
+Signed-off-by: Daniel Vetter <daniel.vetter@intel.com>
+Reviewed-by: Javier Martinez Canillas <javierm@redhat.com>
+Acked-by: Helge Deller <deller@gmx.de>
+Tested-by: Xingyuan Mo <hdthky0@gmail.com>
+Fixes: b07db3958485 ("fbcon: Ditch error handling for con2fb_release_oldinfo")
+Cc: Thomas Zimmermann <tzimmermann@suse.de>
+Cc: Sam Ravnborg <sam@ravnborg.org>
+Cc: Xingyuan Mo <hdthky0@gmail.com>
+Cc: Thomas Zimmermann <tzimmermann@suse.de>
+Cc: Helge Deller <deller@gmx.de>
+Cc: <stable@vger.kernel.org> # v5.19+
+Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
+Signed-off-by: Jiri Slaby <jslaby@suse.cz>
+---
+ drivers/video/fbdev/core/fbcon.c | 17 ++++++++---------
+ 1 file changed, 8 insertions(+), 9 deletions(-)
+
+diff --git a/drivers/video/fbdev/core/fbcon.c b/drivers/video/fbdev/core/fbcon.c
+index 2bc8baa9..b9dc29d6 100644
+--- a/drivers/video/fbdev/core/fbcon.c
++++ b/drivers/video/fbdev/core/fbcon.c
+@@ -823,7 +823,7 @@ static int set_con2fb_map(int unit, int newidx, int user)
+ 	int oldidx = con2fb_map[unit];
+ 	struct fb_info *info = fbcon_registered_fb[newidx];
+ 	struct fb_info *oldinfo = NULL;
+-	int found, err = 0, show_logo;
++	int err = 0, show_logo;
+ 
+ 	WARN_CONSOLE_UNLOCKED();
+ 
+@@ -841,26 +841,25 @@ static int set_con2fb_map(int unit, int newidx, int user)
+ 	if (oldidx != -1)
+ 		oldinfo = fbcon_registered_fb[oldidx];
+ 
+-	found = search_fb_in_map(newidx);
+-
+-	if (!err && !found) {
++	if (!search_fb_in_map(newidx)) {
+ 		err = con2fb_acquire_newinfo(vc, info, unit);
+-		if (!err)
+-			con2fb_map[unit] = newidx;
++		if (err)
++			return err;
++
++		con2fb_map[unit] = newidx;
++		fbcon_add_cursor_work(info);
+ 	}
+ 
+ 	/*
+ 	 * If old fb is not mapped to any of the consoles,
+ 	 * fbcon should release it.
+ 	 */
+-	if (!err && oldinfo && !search_fb_in_map(oldidx))
++	if (oldinfo && !search_fb_in_map(oldidx))
+ 		con2fb_release_oldinfo(vc, oldinfo, info);
+ 
+ 	show_logo = (fg_console == 0 && !user &&
+ 			 logo_shown != FBCON_LOGO_DONTSHOW);
+ 
+-	if (!found)
+-		fbcon_add_cursor_work(info);
+ 	con2fb_map_boot[unit] = newidx;
+ 	con2fb_init_display(vc, info, unit, show_logo);
+ 
+-- 
+2.35.3
+
diff --git a/series.conf b/series.conf
index dcabfc4..1863c69 100644
--- a/series.conf
+++ b/series.conf
@@ -2253,6 +2253,7 @@
 	patches.kernel.org/6.2.12-023-mtd-rawnand-stm32_fmc2-remove-unsupported-EDO-.patch
 	patches.kernel.org/6.2.12-024-mtd-rawnand-stm32_fmc2-use-timings.mode-instea.patch
 	patches.kernel.org/6.2.12-025-KVM-arm64-PMU-Restore-the-guest-s-EL0-event-co.patch
+	patches.kernel.org/6.2.12-026-fbcon-Fix-error-paths-in-set_con2fb_map.patch
 
 	########################################################
 	# Build fixes that apply to the vanilla kernel too.