diff options
Diffstat (limited to 'common/recipes-kernel/linux/linux-yocto-4.14.71/4857-drm-amd-display-dc-dce-Fix-multiple-potential-intege.patch')
| -rw-r--r-- | common/recipes-kernel/linux/linux-yocto-4.14.71/4857-drm-amd-display-dc-dce-Fix-multiple-potential-intege.patch | 70 |
1 files changed, 70 insertions, 0 deletions
diff --git a/common/recipes-kernel/linux/linux-yocto-4.14.71/4857-drm-amd-display-dc-dce-Fix-multiple-potential-intege.patch b/common/recipes-kernel/linux/linux-yocto-4.14.71/4857-drm-amd-display-dc-dce-Fix-multiple-potential-intege.patch new file mode 100644 index 00000000..a4216c60 --- /dev/null +++ b/common/recipes-kernel/linux/linux-yocto-4.14.71/4857-drm-amd-display-dc-dce-Fix-multiple-potential-intege.patch @@ -0,0 +1,70 @@ +From 1f5b35820dc07720fdd328e6d434ff1b5c243514 Mon Sep 17 00:00:00 2001 +From: "Gustavo A. R. Silva" <gustavo@embeddedor.com> +Date: Wed, 4 Jul 2018 08:22:11 -0500 +Subject: [PATCH 4857/5725] drm/amd/display/dc/dce: Fix multiple potential + integer overflows + +Add suffix ULL to constant 5 and cast variables target_pix_clk_khz and +feedback_divider to uint64_t in order to avoid multiple potential integer +overflows and give the compiler complete information about the proper +arithmetic to use. + +Notice that such constant and variables are used in contexts that +expect expressions of type uint64_t (64 bits, unsigned). The current +casts to uint64_t effectively apply to each expression as a whole, +but they do not prevent them from being evaluated using 32-bit +arithmetic instead of 64-bit arithmetic. + +Also, once the expressions are properly evaluated using 64-bit +arithmentic, there is no need for the parentheses that enclose +them. + +Addresses-Coverity-ID: 1460245 ("Unintentional integer overflow") +Addresses-Coverity-ID: 1460286 ("Unintentional integer overflow") +Addresses-Coverity-ID: 1460401 ("Unintentional integer overflow") +Fixes: 4562236b3bc0 ("drm/amd/dc: Add dc display driver (v2)") +Signed-off-by: Gustavo A. R. Silva <gustavo@embeddedor.com> +Reviewed-by: Harry Wentland <harry.wentland@amd.com> +Signed-off-by: Alex Deucher <alexander.deucher@amd.com> +--- + drivers/gpu/drm/amd/display/dc/dce/dce_clock_source.c | 10 +++++----- + 1 file changed, 5 insertions(+), 5 deletions(-) + +diff --git a/drivers/gpu/drm/amd/display/dc/dce/dce_clock_source.c b/drivers/gpu/drm/amd/display/dc/dce/dce_clock_source.c +index 599c7ab..f72f331 100644 +--- a/drivers/gpu/drm/amd/display/dc/dce/dce_clock_source.c ++++ b/drivers/gpu/drm/amd/display/dc/dce/dce_clock_source.c +@@ -133,7 +133,7 @@ static bool calculate_fb_and_fractional_fb_divider( + uint64_t feedback_divider; + + feedback_divider = +- (uint64_t)(target_pix_clk_khz * ref_divider * post_divider); ++ (uint64_t)target_pix_clk_khz * ref_divider * post_divider; + feedback_divider *= 10; + /* additional factor, since we divide by 10 afterwards */ + feedback_divider *= (uint64_t)(calc_pll_cs->fract_fb_divider_factor); +@@ -145,8 +145,8 @@ static bool calculate_fb_and_fractional_fb_divider( + * of fractional feedback decimal point and the fractional FB Divider precision + * is 2 then the equation becomes (ullfeedbackDivider + 5*100) / (10*100))*/ + +- feedback_divider += (uint64_t) +- (5 * calc_pll_cs->fract_fb_divider_precision_factor); ++ feedback_divider += 5ULL * ++ calc_pll_cs->fract_fb_divider_precision_factor; + feedback_divider = + div_u64(feedback_divider, + calc_pll_cs->fract_fb_divider_precision_factor * 10); +@@ -203,8 +203,8 @@ static bool calc_fb_divider_checking_tolerance( + &fract_feedback_divider); + + /*Actual calculated value*/ +- actual_calc_clk_khz = (uint64_t)(feedback_divider * +- calc_pll_cs->fract_fb_divider_factor) + ++ actual_calc_clk_khz = (uint64_t)feedback_divider * ++ calc_pll_cs->fract_fb_divider_factor + + fract_feedback_divider; + actual_calc_clk_khz *= calc_pll_cs->ref_freq_khz; + actual_calc_clk_khz = +-- +2.7.4 + |