diff options
| author | Damian Kos <dkos@cadence.com> | 2018-11-06 15:37:05 +0000 |
|---|---|---|
| committer | Heiko Stuebner <heiko@sntech.de> | 2018-11-19 14:59:50 +0100 |
| commit | fa68d4f8476bea4cdf441062b614b41bb85ef1da (patch) | |
| tree | 092cca7931880e09cbdb9133d0574fd41558c744 /drivers/gpu/drm/rockchip | |
| parent | 21d808405fe49028036932dd969920f4fee4f481 (diff) | |
drm/rockchip: fix for mailbox read size
Some of the functions (like cdn_dp_dpcd_read, cdn_dp_get_edid_block)
allow to read 64KiB, but the cdn_dp_mailbox_read_receive, that is
used by them, can read only up to 255 bytes at once. Normally, it's
not a big issue as DPCD or EDID reads won't (hopefully) exceed that
value.
The real issue here is the revocation list read during the HDCP
authentication process. (problematic use case:
https://chromium.googlesource.com/chromiumos/third_party/kernel/+/chromeos-4.4/drivers/gpu/drm/rockchip/cdn-dp-reg.c#1152)
The list can reach 127*5+4 bytes (num devs * 5 bytes per ID/Bksv +
4 bytes of an additional info).
In other words - CTSes with HDCP Repeater won't pass without this
fix. Oh, and the driver will most likely stop working (best case
scenario).
Signed-off-by: Damian Kos <dkos@cadence.com>
Signed-off-by: Heiko Stuebner <heiko@sntech.de>
Link: https://patchwork.freedesktop.org/patch/msgid/1541518625-25984-1-git-send-email-dkos@cadence.com
Diffstat (limited to 'drivers/gpu/drm/rockchip')
| -rw-r--r-- | drivers/gpu/drm/rockchip/cdn-dp-reg.c | 2 |
1 files changed, 1 insertions, 1 deletions
diff --git a/drivers/gpu/drm/rockchip/cdn-dp-reg.c b/drivers/gpu/drm/rockchip/cdn-dp-reg.c index 3105965fc260..5a485489a1e2 100644 --- a/drivers/gpu/drm/rockchip/cdn-dp-reg.c +++ b/drivers/gpu/drm/rockchip/cdn-dp-reg.c @@ -147,7 +147,7 @@ static int cdn_dp_mailbox_validate_receive(struct cdn_dp_device *dp, } static int cdn_dp_mailbox_read_receive(struct cdn_dp_device *dp, - u8 *buff, u8 buff_size) + u8 *buff, u16 buff_size) { u32 i; int ret; |