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 the 4.4-stable tree which can be found at: http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary The filename of the patch is: video-hgafb-correctly-handle-card-detect-failure-during-probe.patch and it can be found in the queue-4.4 subdirectory. If you, or anyone else, feels it should not be added to the stable tree, please let <stable@xxxxxxxxxxxxxxx> know about it. >From 02625c965239b71869326dd0461615f27307ecb3 Mon Sep 17 00:00:00 2001 From: Anirudh Rayabharam <mail@xxxxxxxxxxxxx> Date: Mon, 17 May 2021 00:57:14 +0530 Subject: video: hgafb: correctly handle card detect failure during probe From: Anirudh Rayabharam <mail@xxxxxxxxxxxxx> commit 02625c965239b71869326dd0461615f27307ecb3 upstream. 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@xxxxxxxxxxxxxxx> Reported-by: kernel test robot <oliver.sang@xxxxxxxxx> Reviewed-by: Igor Matheus Andrade Torrente <igormtorrente@xxxxxxxxx> Signed-off-by: Anirudh Rayabharam <mail@xxxxxxxxxxxxx> Signed-off-by: Dan Carpenter <dan.carpenter@xxxxxxxxxx> Link: https://lore.kernel.org/r/20210516192714.25823-1-mail@xxxxxxxxxxxxx Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> --- drivers/video/fbdev/hgafb.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) --- a/drivers/video/fbdev/hgafb.c +++ b/drivers/video/fbdev/hgafb.c @@ -558,7 +558,7 @@ static int hgafb_probe(struct platform_d int ret; ret = hga_card_detect(); - if (!ret) + if (ret) return ret; printk(KERN_INFO "hgafb: %s with %ldK of memory detected.\n", Patches currently in stable-queue which might be from mail@xxxxxxxxxxxxx are queue-4.4/video-hgafb-correctly-handle-card-detect-failure-during-probe.patch queue-4.4/net-stmicro-handle-clk_prepare-failure-during-init.patch