Variable var->pixclock can be set by user. In case it equals to zero, divide by zero would occur in sstfb_check_var. Similar crashes have happened in other fbdev drivers. We fix this by checking whether 'pixclock' is zero.
Signed-off-by: Alex Guo <[email protected]> --- drivers/video/fbdev/sstfb.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/drivers/video/fbdev/sstfb.c b/drivers/video/fbdev/sstfb.c index 2ea947f57efb..fd387ca8401b 100644 --- a/drivers/video/fbdev/sstfb.c +++ b/drivers/video/fbdev/sstfb.c @@ -359,7 +359,7 @@ static int sstfb_check_var(struct fb_var_screeninfo *var, int tiles_in_X, real_length; unsigned int freq; - if (sst_calc_pll(PICOS2KHZ(var->pixclock), &freq, &par->pll)) { + if (var->pixclock && sst_calc_pll(PICOS2KHZ(var->pixclock), &freq, &par->pll)) { printk(KERN_ERR "sstfb: Pixclock at %ld KHZ out of range\n", PICOS2KHZ(var->pixclock)); return -EINVAL; -- 2.34.1
