From: Tuo Li <islituo@gmail.com> stable inclusion from stable-5.10.67 commit 83449db3aac0895147eac723bf23d0739720b968 bugzilla: 182619 https://gitee.com/openeuler/kernel/issues/I4EWO7 Reference: https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?id=... -------------------------------- [ 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> Signed-off-by: Chen Jun <chenjun102@huawei.com> Acked-by: Weilong Chen <chenweilong@huawei.com> Signed-off-by: Chen Jun <chenjun102@huawei.com> --- .../gpu/drm/amd/display/dc/dcn10/dcn10_hw_sequencer.c | 11 +++++------ 1 file changed, 5 insertions(+), 6 deletions(-) diff --git a/drivers/gpu/drm/amd/display/dc/dcn10/dcn10_hw_sequencer.c b/drivers/gpu/drm/amd/display/dc/dcn10/dcn10_hw_sequencer.c index 0d1e7b56fb39..532f6a1145b5 100644 --- a/drivers/gpu/drm/amd/display/dc/dcn10/dcn10_hw_sequencer.c +++ b/drivers/gpu/drm/amd/display/dc/dcn10/dcn10_hw_sequencer.c @@ -3740,13 +3740,12 @@ 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; @@ -3764,7 +3763,7 @@ 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; -- 2.20.1