From: Wentao Liang <vulab@iscas.ac.cn> mainline inclusion from mainline-v6.16-rc1 commit c3e9826a22027a21d998d3e64882fa377b613006 category: bugfix bugzilla: https://gitee.com/src-openeuler/kernel/issues/ICOXDP CVE: CVE-2025-38362 Reference: https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?i... -------------------------------- The function mod_hdcp_hdcp1_enable_encryption() calls the function get_first_active_display(), but does not check its return value. The return value is a null pointer if the display list is empty. This will lead to a null pointer dereference in mod_hdcp_hdcp2_enable_encryption(). Add a null pointer check for get_first_active_display() and return MOD_HDCP_STATUS_DISPLAY_NOT_FOUND if the function return null. Fixes: 2deade5ede56 ("drm/amd/display: Remove hdcp display state with mst fix") Signed-off-by: Wentao Liang <vulab@iscas.ac.cn> Reviewed-by: Alex Hung <alex.hung@amd.com> Signed-off-by: Alex Deucher <alexander.deucher@amd.com> Cc: stable@vger.kernel.org # v5.8 Conflicts: drivers/gpu/drm/amd/display/modules/hdcp/hdcp_psp.c [Commit ce97f37be895 ("drm/amd: consolidate TA shared memory structures") was not merged, context conflicts.] Signed-off-by: Yi Yang <yiyang13@huawei.com> --- drivers/gpu/drm/amd/display/modules/hdcp/hdcp_psp.c | 3 +++ 1 file changed, 3 insertions(+) diff --git a/drivers/gpu/drm/amd/display/modules/hdcp/hdcp_psp.c b/drivers/gpu/drm/amd/display/modules/hdcp/hdcp_psp.c index 05d96fa68135..20cf95869bd1 100644 --- a/drivers/gpu/drm/amd/display/modules/hdcp/hdcp_psp.c +++ b/drivers/gpu/drm/amd/display/modules/hdcp/hdcp_psp.c @@ -247,6 +247,9 @@ enum mod_hdcp_status mod_hdcp_hdcp1_enable_encryption(struct mod_hdcp *hdcp) struct mod_hdcp_display *display = get_first_active_display(hdcp); enum mod_hdcp_status status = MOD_HDCP_STATUS_SUCCESS; + if (!display) + return MOD_HDCP_STATUS_DISPLAY_NOT_FOUND; + mutex_lock(&psp->hdcp_context.mutex); hdcp_cmd = (struct ta_hdcp_shared_memory *)psp->hdcp_context.hdcp_shared_buf; memset(hdcp_cmd, 0, sizeof(struct ta_hdcp_shared_memory)); -- 2.25.1