This is a note to let you know that I've just added the patch titled drm/amd/display: Fix off by one in hdmi_14_process_transaction() to the 5.10-stable tree which can be found at: http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary The filename of the patch is: drm-amd-display-fix-off-by-one-in-hdmi_14_process_tr.patch and it can be found in the queue-5.10 subdirectory. If you, or anyone else, feels it should not be added to the stable tree, please let <stable@xxxxxxxxxxxxxxx> know about it. commit ffcaf0a102a3445f6ff9e46e84b838a0b209299a Author: Dan Carpenter <dan.carpenter@xxxxxxxxxx> Date: Tue Mar 2 14:15:48 2021 +0300 drm/amd/display: Fix off by one in hdmi_14_process_transaction() [ Upstream commit 8e6fafd5a22e7a2eb216f5510db7aab54cc545c1 ] The hdcp_i2c_offsets[] array did not have an entry for HDCP_MESSAGE_ID_WRITE_CONTENT_STREAM_TYPE so it led to an off by one read overflow. I added an entry and copied the 0x0 value for the offset from similar code in drivers/gpu/drm/amd/display/modules/hdcp/hdcp_ddc.c. I also declared several of these arrays as having HDCP_MESSAGE_ID_MAX entries. This doesn't change the code, but it's just a belt and suspenders approach to try future proof the code. Fixes: 4c283fdac08a ("drm/amd/display: Add HDCP module") Reviewed-by: Bhawanpreet Lakha <Bhawanpreet.Lakha@xxxxxxx> Signed-off-by: Dan Carpenter <dan.carpenter@xxxxxxxxxx> Signed-off-by: Alex Deucher <alexander.deucher@xxxxxxx> Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx> diff --git a/drivers/gpu/drm/amd/display/dc/hdcp/hdcp_msg.c b/drivers/gpu/drm/amd/display/dc/hdcp/hdcp_msg.c index 5e384a8a83dc..51855a2624cf 100644 --- a/drivers/gpu/drm/amd/display/dc/hdcp/hdcp_msg.c +++ b/drivers/gpu/drm/amd/display/dc/hdcp/hdcp_msg.c @@ -39,7 +39,7 @@ #define HDCP14_KSV_SIZE 5 #define HDCP14_MAX_KSV_FIFO_SIZE 127*HDCP14_KSV_SIZE -static const bool hdcp_cmd_is_read[] = { +static const bool hdcp_cmd_is_read[HDCP_MESSAGE_ID_MAX] = { [HDCP_MESSAGE_ID_READ_BKSV] = true, [HDCP_MESSAGE_ID_READ_RI_R0] = true, [HDCP_MESSAGE_ID_READ_PJ] = true, @@ -75,7 +75,7 @@ static const bool hdcp_cmd_is_read[] = { [HDCP_MESSAGE_ID_WRITE_CONTENT_STREAM_TYPE] = false }; -static const uint8_t hdcp_i2c_offsets[] = { +static const uint8_t hdcp_i2c_offsets[HDCP_MESSAGE_ID_MAX] = { [HDCP_MESSAGE_ID_READ_BKSV] = 0x0, [HDCP_MESSAGE_ID_READ_RI_R0] = 0x8, [HDCP_MESSAGE_ID_READ_PJ] = 0xA, @@ -106,7 +106,8 @@ static const uint8_t hdcp_i2c_offsets[] = { [HDCP_MESSAGE_ID_WRITE_REPEATER_AUTH_SEND_ACK] = 0x60, [HDCP_MESSAGE_ID_WRITE_REPEATER_AUTH_STREAM_MANAGE] = 0x60, [HDCP_MESSAGE_ID_READ_REPEATER_AUTH_STREAM_READY] = 0x80, - [HDCP_MESSAGE_ID_READ_RXSTATUS] = 0x70 + [HDCP_MESSAGE_ID_READ_RXSTATUS] = 0x70, + [HDCP_MESSAGE_ID_WRITE_CONTENT_STREAM_TYPE] = 0x0, }; struct protection_properties { @@ -184,7 +185,7 @@ static const struct protection_properties hdmi_14_protection = { .process_transaction = hdmi_14_process_transaction }; -static const uint32_t hdcp_dpcd_addrs[] = { +static const uint32_t hdcp_dpcd_addrs[HDCP_MESSAGE_ID_MAX] = { [HDCP_MESSAGE_ID_READ_BKSV] = 0x68000, [HDCP_MESSAGE_ID_READ_RI_R0] = 0x68005, [HDCP_MESSAGE_ID_READ_PJ] = 0xFFFFFFFF,