drm/amd/display: Fix potential integer overflow

Fix potential integer overflow by casting actual_calculated_clock_100hz
to u64, in order to give the compiler complete information about the
proper arithmetic to use.

Notice that such variable is used in a context that expects
an expression of type u64 (64 bits, unsigned) and the following
expression is currently being evaluated using 32-bit arithmetic:

actual_calculated_clock_100hz * post_divider

Fixes: 7a03fdf628 ("drm/amd/display: fix 64bit division issue on 32bit OS")
Addresses-Coverity-ID: 1501691 ("Unintentional integer overflow")
Signed-off-by: Gustavo A. R. Silva <gustavoars@kernel.org>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
This commit is contained in:
Gustavo A. R. Silva 2021-02-10 15:23:30 -06:00 committed by Alex Deucher
parent e96b1b2974
commit f2d51b20d7
1 changed files with 1 additions and 1 deletions

View File

@ -240,7 +240,7 @@ static bool calc_fb_divider_checking_tolerance(
pll_settings->calculated_pix_clk_100hz =
actual_calculated_clock_100hz;
pll_settings->vco_freq =
div_u64(actual_calculated_clock_100hz * post_divider, 10);
div_u64((u64)actual_calculated_clock_100hz * post_divider, 10);
return true;
}
return false;