drm/display: fix possible null-pointer dereference in dcn10_set_clock()

[ Upstream commit 554594567b1fa3da74f88ec7b2dc83d000c58e98 ]

The variable dc->clk_mgr is checked in:
  if (dc->clk_mgr && dc->clk_mgr->funcs->get_clock)

This indicates dc->clk_mgr can be NULL.
However, it is dereferenced in:
    if (!dc->clk_mgr->funcs->get_clock)

To fix this null-pointer dereference, check dc->clk_mgr and the function
pointer dc->clk_mgr->funcs->get_clock earlier, and return if one of them
is NULL.

Reported-by: TOTE Robot <oslab@tsinghua.edu.cn>
Signed-off-by: Tuo Li <islituo@gmail.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
This commit is contained in:
Tuo Li 2021-08-10 21:07:03 -07:00 committed by Greg Kroah-Hartman
parent cf82fe45be
commit 1e2842fb7e
1 changed files with 5 additions and 6 deletions

View File

@ -3264,13 +3264,12 @@ static enum dc_status dcn10_set_clock(struct dc *dc,
struct dc_clock_config clock_cfg = {0};
struct dc_clocks *current_clocks = &context->bw_ctx.bw.dcn.clk;
if (dc->clk_mgr && dc->clk_mgr->funcs->get_clock)
dc->clk_mgr->funcs->get_clock(dc->clk_mgr,
context, clock_type, &clock_cfg);
if (!dc->clk_mgr->funcs->get_clock)
if (!dc->clk_mgr || !dc->clk_mgr->funcs->get_clock)
return DC_FAIL_UNSUPPORTED_1;
dc->clk_mgr->funcs->get_clock(dc->clk_mgr,
context, clock_type, &clock_cfg);
if (clk_khz > clock_cfg.max_clock_khz)
return DC_FAIL_CLK_EXCEED_MAX;
@ -3288,7 +3287,7 @@ static enum dc_status dcn10_set_clock(struct dc *dc,
else
return DC_ERROR_UNEXPECTED;
if (dc->clk_mgr && dc->clk_mgr->funcs->update_clocks)
if (dc->clk_mgr->funcs->update_clocks)
dc->clk_mgr->funcs->update_clocks(dc->clk_mgr,
context, true);
return DC_OK;