On 10/14/23 14:14, Zhang Shurong wrote:
We can easily use FBIOPUT_VSCREENINFO set fb_var_screeninfo, so
it's possible for a divide by zero error to occur.
Fix this by making sure the divisor is non-zero before the computation.
Signed-off-by: Zhang Shurong <zhang_shurong@xxxxxxxxxxx>
---
drivers/video/fbdev/core/fbmon.c | 3 +++
1 file changed, 3 insertions(+)
diff --git a/drivers/video/fbdev/core/fbmon.c b/drivers/video/fbdev/core/fbmon.c
index 79e5bfbdd34c..bdd15b8e3a71 100644
--- a/drivers/video/fbdev/core/fbmon.c
+++ b/drivers/video/fbdev/core/fbmon.c
@@ -1470,6 +1470,9 @@ int fb_validate_mode(const struct fb_var_screeninfo *var, struct fb_info *info)
if (var->vmode & FB_VMODE_DOUBLE)
vtotal *= 2;
+ if (!htotal || !vtotal)
+ return -EINVAL;
This is above here:
htotal = var->xres + var->right_margin + var->hsync_len +
var->left_margin;
vtotal = var->yres + var->lower_margin + var->vsync_len +
var->upper_margin;
I don't see how htotal and vtotal can become zero...
Helge
