Hi,
On 5/16/21 4:27 PM, Anirudh Rayabharam wrote:
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/
Reported-by: kernel test robot <oliver.sang@xxxxxxxxx>
Fixes: dc13cac4862c ("video: hgafb: fix potential NULL pointer dereference")
Cc: stable <stable@xxxxxxxxxxxxxxx>
Signed-off-by: Anirudh Rayabharam <mail@xxxxxxxxxxxxx>
---
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",
In fact, this return isn't being properly handled. Thanks for fix it!
Reviewed-by: Igor Matheus Andrade Torrente <igormtorrente@xxxxxxxxx>
