[PATCH 5.15 178/317] drm/amd/display: Fix a potential buffer overflow in 'dp_dsc_clock_en_read()'

From: Sasha Levin
Date: Mon Mar 25 2024 - 02:45:52 EST


From: Srinivasan Shanmugam <srinivasan.shanmugam@xxxxxxx>

[ Upstream commit 4b09715f1504f1b6e8dff0e9643630610bc05141 ]

Tell snprintf() to store at most 10 bytes in the output buffer
instead of 30.

Fixes the below:
drivers/gpu/drm/amd/amdgpu/../display/amdgpu_dm/amdgpu_dm_debugfs.c:1508 dp_dsc_clock_en_read() error: snprintf() is printing too much 30 vs 10

Fixes: c06e09b76639 ("drm/amd/display: Add DSC parameters logging to debugfs")
Cc: Alex Hung <alex.hung@xxxxxxx>
Cc: Qingqing Zhuo <qingqing.zhuo@xxxxxxx>
Cc: Rodrigo Siqueira <Rodrigo.Siqueira@xxxxxxx>
Cc: Aurabindo Pillai <aurabindo.pillai@xxxxxxx>
Cc: Alex Deucher <alexander.deucher@xxxxxxx>
Signed-off-by: Srinivasan Shanmugam <srinivasan.shanmugam@xxxxxxx>
Reviewed-by: Harry Wentland <harry.wentland@xxxxxxx>
Signed-off-by: Alex Deucher <alexander.deucher@xxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
---
drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm_debugfs.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm_debugfs.c b/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm_debugfs.c
index 6d694cea24201..ed2f6802b0e20 100644
--- a/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm_debugfs.c
+++ b/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm_debugfs.c
@@ -1304,7 +1304,7 @@ static ssize_t dp_dsc_clock_en_read(struct file *f, char __user *buf,
const uint32_t rd_buf_size = 10;
struct pipe_ctx *pipe_ctx;
ssize_t result = 0;
- int i, r, str_len = 30;
+ int i, r, str_len = 10;

rd_buf = kcalloc(rd_buf_size, sizeof(char), GFP_KERNEL);

--
2.43.0