This is a note to let you know that I've just added the patch titled
fbdev: nvidia: Fix potential divide by zero
to the 5.15-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:
fbdev-nvidia-fix-potential-divide-by-zero.patch
and it can be found in the queue-5.15 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@xxxxxxxxxxxxxxx> know about it.
commit 8bd68366c0c39507b275f489dceb54360df661f2
Author: Wei Chen <harperchen1110@xxxxxxxxx>
Date: Wed Mar 15 07:18:31 2023 +0000
fbdev: nvidia: Fix potential divide by zero
[ Upstream commit 92e2a00f2987483e1f9253625828622edd442e61 ]
variable var->pixclock can be set by user. In case it
equals to zero, divide by zero would occur in nvidiafb_set_par.
Similar crashes have happened in other fbdev drivers. There
is no check and modification on var->pixclock along the call
chain to nvidia_check_var and nvidiafb_set_par. We believe it
could also be triggered in driver nvidia from user site.
Signed-off-by: Wei Chen <harperchen1110@xxxxxxxxx>
Signed-off-by: Helge Deller <deller@xxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
diff --git a/drivers/video/fbdev/nvidia/nvidia.c b/drivers/video/fbdev/nvidia/nvidia.c
index a372a183c1f01..f9c388a8c10e3 100644
--- a/drivers/video/fbdev/nvidia/nvidia.c
+++ b/drivers/video/fbdev/nvidia/nvidia.c
@@ -763,6 +763,8 @@ static int nvidiafb_check_var(struct fb_var_screeninfo *var,
int pitch, err = 0;
NVTRACE_ENTER();
+ if (!var->pixclock)
+ return -EINVAL;
var->transp.offset = 0;
var->transp.length = 0;
