| 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 |
| |
| From: Anirudh Rayabharam <mail@anirudhrb.com> |
| |
| 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@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(-) |
| |
| --- 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", |
