patch "video: hgafb: correctly handle card detect failure during probe" added to char-misc-linus

This is a note to let you know that I've just added the patch titled

video: hgafb: correctly handle card detect failure during probe

to my char-misc git tree which can be found at
git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/char-misc.git
in the char-misc-linus branch.

The patch will show up in the next release of the linux-next tree (usually sometime within the next 24 hours during the week.)

The patch will hopefully also be merged in Linus's tree for the next -rc kernel release.

If you have any questions about this process, please let me know.

From 02625c965239b71869326dd0461615f27307ecb3 Mon Sep 17 00:00:00 2001
From: Anirudh Rayabharam <[email protected]>
Date: Mon, 17 May 2021 00:57:14 +0530
Subject: video: hgafb: correctly handle card detect failure during probe

The return value of hga_card_detect() is not properly handled causing the probe to succeed even though hga_card_detect() failed. Since probe succeeds, hgafb_open() can be called which will end up operating on an unmapped hga_vram. This results in an out-of-bounds access as reported by kernel test robot [1].

To fix this, correctly detect failure of hga_card_detect() by checking for a non-zero error code.

[1]: https://lore.kernel.org/lkml/20210516150019.GB25903@xsang-OptiPlex-9020/

---
 drivers/video/fbdev/hgafb.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

index cc8e62ae93f6..bd3d07aa4f0e 100644
@@ -558,7 +558,7 @@ static int hgafb_probe(struct platform_device *pdev)
 	int ret;
 
 	ret = hga_card_detect();
-	if (!ret)
+	if (ret)
 		return ret;
 
 	printk(KERN_INFO "hgafb: %s with %ldK of memory detected.\n",

2.31.1