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 mail@anirudhrb.com 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/
Fixes: dc13cac4862c ("video: hgafb: fix potential NULL pointer dereference") Cc: stable stable@vger.kernel.org Reported-by: kernel test robot oliver.sang@intel.com Reviewed-by: Igor Matheus Andrade Torrente igormtorrente@gmail.com Signed-off-by: Anirudh Rayabharam mail@anirudhrb.com Signed-off-by: Dan Carpenter dan.carpenter@oracle.com Link: https://lore.kernel.org/r/20210516192714.25823-1-mail@anirudhrb.com Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org --- drivers/video/fbdev/hgafb.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/drivers/video/fbdev/hgafb.c b/drivers/video/fbdev/hgafb.c index cc8e62ae93f6..bd3d07aa4f0e 100644 --- a/drivers/video/fbdev/hgafb.c +++ b/drivers/video/fbdev/hgafb.c @@ -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",