drm/amd/display: Clamp VBIOS HDMI retimer register count to array size

[Why & How]
The VBIOS integrated info tables (v1_11 and v2_1) contain HdmiRegNum and
Hdmi6GRegNum fields that are used as loop bounds when copying retimer I2C
register settings into fixed-size arrays (dp*_ext_hdmi_reg_settings[9]
and dp*_ext_hdmi_6g_reg_settings[3]). These u8 fields are not validated
before use, so a malformed VBIOS can specify values up to 255, causing an
out-of-bounds heap write during driver probe.

Clamp each register count to the destination array size using min_t()
before the copy loops, in both get_integrated_info_v11() and
get_integrated_info_v2_1().

Assisted-by: GitHub Copilot:claude-opus-4.6
Reviewed-by: Alex Hung <alex.hung@amd.com>
Signed-off-by: Harry Wentland <harry.wentland@amd.com>
Signed-off-by: Ray Wu <ray.wu@amd.com>
Tested-by: Daniel Wheeler <daniel.wheeler@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
(cherry picked from commit 5a7f0ef901)
Cc: stable@vger.kernel.org
This commit is contained in:
Harry Wentland 2026-05-04 15:51:13 -04:00 committed by Alex Deucher
parent e8b4d37eba
commit fb0707ce00

View File

@ -2600,14 +2600,16 @@ static enum bp_result get_integrated_info_v11(
info_v11->extdispconninfo.checksum;
info->dp0_ext_hdmi_slv_addr = info_v11->dp0_retimer_set.HdmiSlvAddr;
info->dp0_ext_hdmi_reg_num = info_v11->dp0_retimer_set.HdmiRegNum;
info->dp0_ext_hdmi_reg_num = min_t(u8, info_v11->dp0_retimer_set.HdmiRegNum,
ARRAY_SIZE(info->dp0_ext_hdmi_reg_settings));
for (i = 0; i < info->dp0_ext_hdmi_reg_num; i++) {
info->dp0_ext_hdmi_reg_settings[i].i2c_reg_index =
info_v11->dp0_retimer_set.HdmiRegSetting[i].ucI2cRegIndex;
info->dp0_ext_hdmi_reg_settings[i].i2c_reg_val =
info_v11->dp0_retimer_set.HdmiRegSetting[i].ucI2cRegVal;
}
info->dp0_ext_hdmi_6g_reg_num = info_v11->dp0_retimer_set.Hdmi6GRegNum;
info->dp0_ext_hdmi_6g_reg_num = min_t(u8, info_v11->dp0_retimer_set.Hdmi6GRegNum,
ARRAY_SIZE(info->dp0_ext_hdmi_6g_reg_settings));
for (i = 0; i < info->dp0_ext_hdmi_6g_reg_num; i++) {
info->dp0_ext_hdmi_6g_reg_settings[i].i2c_reg_index =
info_v11->dp0_retimer_set.Hdmi6GhzRegSetting[i].ucI2cRegIndex;
@ -2616,14 +2618,16 @@ static enum bp_result get_integrated_info_v11(
}
info->dp1_ext_hdmi_slv_addr = info_v11->dp1_retimer_set.HdmiSlvAddr;
info->dp1_ext_hdmi_reg_num = info_v11->dp1_retimer_set.HdmiRegNum;
info->dp1_ext_hdmi_reg_num = min_t(u8, info_v11->dp1_retimer_set.HdmiRegNum,
ARRAY_SIZE(info->dp1_ext_hdmi_reg_settings));
for (i = 0; i < info->dp1_ext_hdmi_reg_num; i++) {
info->dp1_ext_hdmi_reg_settings[i].i2c_reg_index =
info_v11->dp1_retimer_set.HdmiRegSetting[i].ucI2cRegIndex;
info->dp1_ext_hdmi_reg_settings[i].i2c_reg_val =
info_v11->dp1_retimer_set.HdmiRegSetting[i].ucI2cRegVal;
}
info->dp1_ext_hdmi_6g_reg_num = info_v11->dp1_retimer_set.Hdmi6GRegNum;
info->dp1_ext_hdmi_6g_reg_num = min_t(u8, info_v11->dp1_retimer_set.Hdmi6GRegNum,
ARRAY_SIZE(info->dp1_ext_hdmi_6g_reg_settings));
for (i = 0; i < info->dp1_ext_hdmi_6g_reg_num; i++) {
info->dp1_ext_hdmi_6g_reg_settings[i].i2c_reg_index =
info_v11->dp1_retimer_set.Hdmi6GhzRegSetting[i].ucI2cRegIndex;
@ -2632,14 +2636,16 @@ static enum bp_result get_integrated_info_v11(
}
info->dp2_ext_hdmi_slv_addr = info_v11->dp2_retimer_set.HdmiSlvAddr;
info->dp2_ext_hdmi_reg_num = info_v11->dp2_retimer_set.HdmiRegNum;
info->dp2_ext_hdmi_reg_num = min_t(u8, info_v11->dp2_retimer_set.HdmiRegNum,
ARRAY_SIZE(info->dp2_ext_hdmi_reg_settings));
for (i = 0; i < info->dp2_ext_hdmi_reg_num; i++) {
info->dp2_ext_hdmi_reg_settings[i].i2c_reg_index =
info_v11->dp2_retimer_set.HdmiRegSetting[i].ucI2cRegIndex;
info->dp2_ext_hdmi_reg_settings[i].i2c_reg_val =
info_v11->dp2_retimer_set.HdmiRegSetting[i].ucI2cRegVal;
}
info->dp2_ext_hdmi_6g_reg_num = info_v11->dp2_retimer_set.Hdmi6GRegNum;
info->dp2_ext_hdmi_6g_reg_num = min_t(u8, info_v11->dp2_retimer_set.Hdmi6GRegNum,
ARRAY_SIZE(info->dp2_ext_hdmi_6g_reg_settings));
for (i = 0; i < info->dp2_ext_hdmi_6g_reg_num; i++) {
info->dp2_ext_hdmi_6g_reg_settings[i].i2c_reg_index =
info_v11->dp2_retimer_set.Hdmi6GhzRegSetting[i].ucI2cRegIndex;
@ -2648,14 +2654,16 @@ static enum bp_result get_integrated_info_v11(
}
info->dp3_ext_hdmi_slv_addr = info_v11->dp3_retimer_set.HdmiSlvAddr;
info->dp3_ext_hdmi_reg_num = info_v11->dp3_retimer_set.HdmiRegNum;
info->dp3_ext_hdmi_reg_num = min_t(u8, info_v11->dp3_retimer_set.HdmiRegNum,
ARRAY_SIZE(info->dp3_ext_hdmi_reg_settings));
for (i = 0; i < info->dp3_ext_hdmi_reg_num; i++) {
info->dp3_ext_hdmi_reg_settings[i].i2c_reg_index =
info_v11->dp3_retimer_set.HdmiRegSetting[i].ucI2cRegIndex;
info->dp3_ext_hdmi_reg_settings[i].i2c_reg_val =
info_v11->dp3_retimer_set.HdmiRegSetting[i].ucI2cRegVal;
}
info->dp3_ext_hdmi_6g_reg_num = info_v11->dp3_retimer_set.Hdmi6GRegNum;
info->dp3_ext_hdmi_6g_reg_num = min_t(u8, info_v11->dp3_retimer_set.Hdmi6GRegNum,
ARRAY_SIZE(info->dp3_ext_hdmi_6g_reg_settings));
for (i = 0; i < info->dp3_ext_hdmi_6g_reg_num; i++) {
info->dp3_ext_hdmi_6g_reg_settings[i].i2c_reg_index =
info_v11->dp3_retimer_set.Hdmi6GhzRegSetting[i].ucI2cRegIndex;
@ -2805,14 +2813,16 @@ static enum bp_result get_integrated_info_v2_1(
info->ext_disp_conn_info.checksum =
info_v2_1->extdispconninfo.checksum;
info->dp0_ext_hdmi_slv_addr = info_v2_1->dp0_retimer_set.HdmiSlvAddr;
info->dp0_ext_hdmi_reg_num = info_v2_1->dp0_retimer_set.HdmiRegNum;
info->dp0_ext_hdmi_reg_num = min_t(u8, info_v2_1->dp0_retimer_set.HdmiRegNum,
ARRAY_SIZE(info->dp0_ext_hdmi_reg_settings));
for (i = 0; i < info->dp0_ext_hdmi_reg_num; i++) {
info->dp0_ext_hdmi_reg_settings[i].i2c_reg_index =
info_v2_1->dp0_retimer_set.HdmiRegSetting[i].ucI2cRegIndex;
info->dp0_ext_hdmi_reg_settings[i].i2c_reg_val =
info_v2_1->dp0_retimer_set.HdmiRegSetting[i].ucI2cRegVal;
}
info->dp0_ext_hdmi_6g_reg_num = info_v2_1->dp0_retimer_set.Hdmi6GRegNum;
info->dp0_ext_hdmi_6g_reg_num = min_t(u8, info_v2_1->dp0_retimer_set.Hdmi6GRegNum,
ARRAY_SIZE(info->dp0_ext_hdmi_6g_reg_settings));
for (i = 0; i < info->dp0_ext_hdmi_6g_reg_num; i++) {
info->dp0_ext_hdmi_6g_reg_settings[i].i2c_reg_index =
info_v2_1->dp0_retimer_set.Hdmi6GhzRegSetting[i].ucI2cRegIndex;
@ -2820,14 +2830,16 @@ static enum bp_result get_integrated_info_v2_1(
info_v2_1->dp0_retimer_set.Hdmi6GhzRegSetting[i].ucI2cRegVal;
}
info->dp1_ext_hdmi_slv_addr = info_v2_1->dp1_retimer_set.HdmiSlvAddr;
info->dp1_ext_hdmi_reg_num = info_v2_1->dp1_retimer_set.HdmiRegNum;
info->dp1_ext_hdmi_reg_num = min_t(u8, info_v2_1->dp1_retimer_set.HdmiRegNum,
ARRAY_SIZE(info->dp1_ext_hdmi_reg_settings));
for (i = 0; i < info->dp1_ext_hdmi_reg_num; i++) {
info->dp1_ext_hdmi_reg_settings[i].i2c_reg_index =
info_v2_1->dp1_retimer_set.HdmiRegSetting[i].ucI2cRegIndex;
info->dp1_ext_hdmi_reg_settings[i].i2c_reg_val =
info_v2_1->dp1_retimer_set.HdmiRegSetting[i].ucI2cRegVal;
}
info->dp1_ext_hdmi_6g_reg_num = info_v2_1->dp1_retimer_set.Hdmi6GRegNum;
info->dp1_ext_hdmi_6g_reg_num = min_t(u8, info_v2_1->dp1_retimer_set.Hdmi6GRegNum,
ARRAY_SIZE(info->dp1_ext_hdmi_6g_reg_settings));
for (i = 0; i < info->dp1_ext_hdmi_6g_reg_num; i++) {
info->dp1_ext_hdmi_6g_reg_settings[i].i2c_reg_index =
info_v2_1->dp1_retimer_set.Hdmi6GhzRegSetting[i].ucI2cRegIndex;
@ -2835,14 +2847,16 @@ static enum bp_result get_integrated_info_v2_1(
info_v2_1->dp1_retimer_set.Hdmi6GhzRegSetting[i].ucI2cRegVal;
}
info->dp2_ext_hdmi_slv_addr = info_v2_1->dp2_retimer_set.HdmiSlvAddr;
info->dp2_ext_hdmi_reg_num = info_v2_1->dp2_retimer_set.HdmiRegNum;
info->dp2_ext_hdmi_reg_num = min_t(u8, info_v2_1->dp2_retimer_set.HdmiRegNum,
ARRAY_SIZE(info->dp2_ext_hdmi_reg_settings));
for (i = 0; i < info->dp2_ext_hdmi_reg_num; i++) {
info->dp2_ext_hdmi_reg_settings[i].i2c_reg_index =
info_v2_1->dp2_retimer_set.HdmiRegSetting[i].ucI2cRegIndex;
info->dp2_ext_hdmi_reg_settings[i].i2c_reg_val =
info_v2_1->dp2_retimer_set.HdmiRegSetting[i].ucI2cRegVal;
}
info->dp2_ext_hdmi_6g_reg_num = info_v2_1->dp2_retimer_set.Hdmi6GRegNum;
info->dp2_ext_hdmi_6g_reg_num = min_t(u8, info_v2_1->dp2_retimer_set.Hdmi6GRegNum,
ARRAY_SIZE(info->dp2_ext_hdmi_6g_reg_settings));
for (i = 0; i < info->dp2_ext_hdmi_6g_reg_num; i++) {
info->dp2_ext_hdmi_6g_reg_settings[i].i2c_reg_index =
info_v2_1->dp2_retimer_set.Hdmi6GhzRegSetting[i].ucI2cRegIndex;
@ -2850,14 +2864,16 @@ static enum bp_result get_integrated_info_v2_1(
info_v2_1->dp2_retimer_set.Hdmi6GhzRegSetting[i].ucI2cRegVal;
}
info->dp3_ext_hdmi_slv_addr = info_v2_1->dp3_retimer_set.HdmiSlvAddr;
info->dp3_ext_hdmi_reg_num = info_v2_1->dp3_retimer_set.HdmiRegNum;
info->dp3_ext_hdmi_reg_num = min_t(u8, info_v2_1->dp3_retimer_set.HdmiRegNum,
ARRAY_SIZE(info->dp3_ext_hdmi_reg_settings));
for (i = 0; i < info->dp3_ext_hdmi_reg_num; i++) {
info->dp3_ext_hdmi_reg_settings[i].i2c_reg_index =
info_v2_1->dp3_retimer_set.HdmiRegSetting[i].ucI2cRegIndex;
info->dp3_ext_hdmi_reg_settings[i].i2c_reg_val =
info_v2_1->dp3_retimer_set.HdmiRegSetting[i].ucI2cRegVal;
}
info->dp3_ext_hdmi_6g_reg_num = info_v2_1->dp3_retimer_set.Hdmi6GRegNum;
info->dp3_ext_hdmi_6g_reg_num = min_t(u8, info_v2_1->dp3_retimer_set.Hdmi6GRegNum,
ARRAY_SIZE(info->dp3_ext_hdmi_6g_reg_settings));
for (i = 0; i < info->dp3_ext_hdmi_6g_reg_num; i++) {
info->dp3_ext_hdmi_6g_reg_settings[i].i2c_reg_index =
info_v2_1->dp3_retimer_set.Hdmi6GhzRegSetting[i].ucI2cRegIndex;