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| author | Yizhuo Zhai <yzhai003@ucr.edu> | 2021-12-18 07:22:23 +0300 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2022-01-27 13:05:11 +0300 |
| commit | 3bf997ec299cdf7280b2039806e5e1d847df111a (patch) | |
| tree | 979ae3cc1bf9dc58f3e208c17a49df72d82000d4 /drivers/gpu | |
| parent | 2de6ce5836513f0bfe61d0948d8eb25f1417e7bd (diff) | |
| download | linux-3bf997ec299cdf7280b2039806e5e1d847df111a.tar.xz | |
drm/amd/display: Fix the uninitialized variable in enable_stream_features()
commit 0726ed3065eeb910f9cea0c933bc021a848e00b3 upstream.
In function enable_stream_features(), the variable "old_downspread.raw"
could be uninitialized if core_link_read_dpcd() fails, however, it is
used in the later if statement, and further, core_link_write_dpcd()
may write random value, which is potentially unsafe.
Fixes: 6016cd9dba0f ("drm/amd/display: add helper for enabling mst stream features")
Cc: stable@vger.kernel.org
Signed-off-by: Yizhuo Zhai <yzhai003@ucr.edu>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Diffstat (limited to 'drivers/gpu')
| -rw-r--r-- | drivers/gpu/drm/amd/display/dc/core/dc_link.c | 2 |
1 files changed, 2 insertions, 0 deletions
diff --git a/drivers/gpu/drm/amd/display/dc/core/dc_link.c b/drivers/gpu/drm/amd/display/dc/core/dc_link.c index 1e44b13c1c7d..3c4205248efc 100644 --- a/drivers/gpu/drm/amd/display/dc/core/dc_link.c +++ b/drivers/gpu/drm/amd/display/dc/core/dc_link.c @@ -1696,6 +1696,8 @@ static void enable_stream_features(struct pipe_ctx *pipe_ctx) union down_spread_ctrl old_downspread; union down_spread_ctrl new_downspread; + memset(&old_downspread, 0, sizeof(old_downspread)); + core_link_read_dpcd(link, DP_DOWNSPREAD_CTRL, &old_downspread.raw, sizeof(old_downspread)); |