FAILED: patch "[PATCH] drm/sysfb: simpledrm: Improve stride validation" failed to apply to 6.12-stable tree

[<gregkh@linuxfoundation.org>]

The patch below does not apply to the 6.12-stable tree.
If someone wants it applied there, or to any other stable or longterm
tree, then please email the backport, including the original git commit
id to <stable@vger.kernel.org>.

To reproduce the conflict and resubmit, you may use the following commands:

git fetch https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/ linux-6.12.y
git checkout FETCH_HEAD
git cherry-pick -x df6533f11688aa30be3bb883c7637f4ffdbb7cbd
# <resolve conflicts, build, test, etc.>
git commit -s
git send-email --to '<stable@vger.kernel.org>' --in-reply-to '2026090938-kissing-slacking-a098@gregkh' --subject-prefix 'PATCH 6.12.y' 'HEAD^..'

Possible dependencies:



thanks,

greg k-h

------------------ original commit in Linus's tree ------------------

From df6533f11688aa30be3bb883c7637f4ffdbb7cbd Mon Sep 17 00:00:00 2001
From: Thomas Zimmermann <tzimmermann@suse.de>
Date: Thu, 25 Jun 2026 11:39:36 +0200
Subject: [PATCH] drm/sysfb: simpledrm: Improve stride validation

Validate the computed stride against the maximum value INT_MAX.

Signed-off-by: Thomas Zimmermann <tzimmermann@suse.de>
Reviewed-by: Thierry Reding <treding@nvidia.com>
Reviewed-by: Maxime Ripard <mripard@kernel.org>
Reviewed-by: Javier Martinez Canillas <javierm@redhat.com>
Fixes: 7bfa5c7b28d6 ("drm/simpledrm: Compute linestride with drm_format_info_min_pitch()")
Cc: <stable@vger.kernel.org> # v6.1+
Link: https://patch.msgid.link/20260625094509.157581-5-tzimmermann@suse.de

diff --git a/drivers/gpu/drm/sysfb/simpledrm.c b/drivers/gpu/drm/sysfb/simpledrm.c
index b4e91191a0ba..a899dfb747bf 100644
--- a/drivers/gpu/drm/sysfb/simpledrm.c
+++ b/drivers/gpu/drm/sysfb/simpledrm.c
@@ -703,9 +703,15 @@ static struct simpledrm_device *simpledrm_device_create(struct drm_driver *drv,
 		return ERR_PTR(-ENODEV);
 	}
 	if (!stride) {
-		stride = drm_format_info_min_pitch(format, 0, width);
-		if (drm_WARN_ON(dev, !stride))
+		u64 pitch = drm_format_info_min_pitch(format, 0, width);
+
+		if (drm_WARN_ON(dev, !pitch)) {
+			return ERR_PTR(-EINVAL); /* driver bug */
+		} else if (pitch > INT_MAX) {
+			drm_warn(dev, "stride of %llu exceeds maximum\n", pitch);
 			return ERR_PTR(-EINVAL);
+		}
+		stride = pitch;
 	}
 
 	sysfb->fb_mode = drm_sysfb_mode(width, height, width_mm, height_mm);