From a4b40d5d97f5c9ad0b7f4bf2818291ca184bb433 Mon Sep 17 00:00:00 2001 From: Alex Deucher Date: Mon, 14 Feb 2011 11:43:10 -0500 Subject: [PATCH] drm/radeon/kms: add bounds checking to avivo pll algo Prevent divider overflow. Fixes: https://bugzilla.kernel.org/show_bug.cgi?id=28932 Signed-off-by: Alex Deucher Cc: stable@kernel.org Signed-off-by: Dave Airlie --- drivers/gpu/drm/radeon/radeon_display.c | 10 ++++++++++ 1 file changed, 10 insertions(+) diff --git a/drivers/gpu/drm/radeon/radeon_display.c b/drivers/gpu/drm/radeon/radeon_display.c index 2eff98c..0e65709 100644 --- a/drivers/gpu/drm/radeon/radeon_display.c +++ b/drivers/gpu/drm/radeon/radeon_display.c @@ -793,6 +793,11 @@ static void avivo_get_fb_div(struct radeon_pll *pll, tmp *= target_clock; *fb_div = tmp / pll->reference_freq; *frac_fb_div = tmp % pll->reference_freq; + + if (*fb_div > pll->max_feedback_div) + *fb_div = pll->max_feedback_div; + else if (*fb_div < pll->min_feedback_div) + *fb_div = pll->min_feedback_div; } static u32 avivo_get_post_div(struct radeon_pll *pll, @@ -826,6 +831,11 @@ static u32 avivo_get_post_div(struct radeon_pll *pll, post_div--; } + if (post_div > pll->max_post_div) + post_div = pll->max_post_div; + else if (post_div < pll->min_post_div) + post_div = pll->min_post_div; + return post_div; } -- 2.7.4