[PATCH 5.15 020/277] drm/amd/display: Fix memory leak

From: Greg Kroah-Hartman
Date: Tue Apr 12 2022 - 02:59:27 EST


From: Yongzhi Liu <lyz_cs@xxxxxxxxxx>

[ Upstream commit 5d5c6dba2b43e28845d7d7ed32a36802329a5f52 ]

[why]
Resource release is needed on the error handling path
to prevent memory leak.

[how]
Fix this by adding kfree on the error handling path.

Reviewed-by: Harry Wentland <harry.wentland@xxxxxxx>
Signed-off-by: Yongzhi Liu <lyz_cs@xxxxxxxxxx>
Signed-off-by: Alex Deucher <alexander.deucher@xxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
---
.../amd/display/amdgpu_dm/amdgpu_dm_debugfs.c | 80 ++++++++++++++-----
1 file changed, 60 insertions(+), 20 deletions(-)

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 e94ddd5e7b63..5c9f5214bc4e 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
@@ -229,8 +229,10 @@ static ssize_t dp_link_settings_read(struct file *f, char __user *buf,
break;

r = put_user(*(rd_buf + result), buf);
- if (r)
+ if (r) {
+ kfree(rd_buf);
return r; /* r = -EFAULT */
+ }

buf += 1;
size -= 1;
@@ -388,8 +390,10 @@ static ssize_t dp_phy_settings_read(struct file *f, char __user *buf,
break;

r = put_user((*(rd_buf + result)), buf);
- if (r)
+ if (r) {
+ kfree(rd_buf);
return r; /* r = -EFAULT */
+ }

buf += 1;
size -= 1;
@@ -1316,8 +1320,10 @@ static ssize_t dp_dsc_clock_en_read(struct file *f, char __user *buf,
break;
}

- if (!pipe_ctx)
+ if (!pipe_ctx) {
+ kfree(rd_buf);
return -ENXIO;
+ }

dsc = pipe_ctx->stream_res.dsc;
if (dsc)
@@ -1333,8 +1339,10 @@ static ssize_t dp_dsc_clock_en_read(struct file *f, char __user *buf,
break;

r = put_user(*(rd_buf + result), buf);
- if (r)
+ if (r) {
+ kfree(rd_buf);
return r; /* r = -EFAULT */
+ }

buf += 1;
size -= 1;
@@ -1503,8 +1511,10 @@ static ssize_t dp_dsc_slice_width_read(struct file *f, char __user *buf,
break;
}

- if (!pipe_ctx)
+ if (!pipe_ctx) {
+ kfree(rd_buf);
return -ENXIO;
+ }

dsc = pipe_ctx->stream_res.dsc;
if (dsc)
@@ -1520,8 +1530,10 @@ static ssize_t dp_dsc_slice_width_read(struct file *f, char __user *buf,
break;

r = put_user(*(rd_buf + result), buf);
- if (r)
+ if (r) {
+ kfree(rd_buf);
return r; /* r = -EFAULT */
+ }

buf += 1;
size -= 1;
@@ -1688,8 +1700,10 @@ static ssize_t dp_dsc_slice_height_read(struct file *f, char __user *buf,
break;
}

- if (!pipe_ctx)
+ if (!pipe_ctx) {
+ kfree(rd_buf);
return -ENXIO;
+ }

dsc = pipe_ctx->stream_res.dsc;
if (dsc)
@@ -1705,8 +1719,10 @@ static ssize_t dp_dsc_slice_height_read(struct file *f, char __user *buf,
break;

r = put_user(*(rd_buf + result), buf);
- if (r)
+ if (r) {
+ kfree(rd_buf);
return r; /* r = -EFAULT */
+ }

buf += 1;
size -= 1;
@@ -1869,8 +1885,10 @@ static ssize_t dp_dsc_bits_per_pixel_read(struct file *f, char __user *buf,
break;
}

- if (!pipe_ctx)
+ if (!pipe_ctx) {
+ kfree(rd_buf);
return -ENXIO;
+ }

dsc = pipe_ctx->stream_res.dsc;
if (dsc)
@@ -1886,8 +1904,10 @@ static ssize_t dp_dsc_bits_per_pixel_read(struct file *f, char __user *buf,
break;

r = put_user(*(rd_buf + result), buf);
- if (r)
+ if (r) {
+ kfree(rd_buf);
return r; /* r = -EFAULT */
+ }

buf += 1;
size -= 1;
@@ -2045,8 +2065,10 @@ static ssize_t dp_dsc_pic_width_read(struct file *f, char __user *buf,
break;
}

- if (!pipe_ctx)
+ if (!pipe_ctx) {
+ kfree(rd_buf);
return -ENXIO;
+ }

dsc = pipe_ctx->stream_res.dsc;
if (dsc)
@@ -2062,8 +2084,10 @@ static ssize_t dp_dsc_pic_width_read(struct file *f, char __user *buf,
break;

r = put_user(*(rd_buf + result), buf);
- if (r)
+ if (r) {
+ kfree(rd_buf);
return r; /* r = -EFAULT */
+ }

buf += 1;
size -= 1;
@@ -2102,8 +2126,10 @@ static ssize_t dp_dsc_pic_height_read(struct file *f, char __user *buf,
break;
}

- if (!pipe_ctx)
+ if (!pipe_ctx) {
+ kfree(rd_buf);
return -ENXIO;
+ }

dsc = pipe_ctx->stream_res.dsc;
if (dsc)
@@ -2119,8 +2145,10 @@ static ssize_t dp_dsc_pic_height_read(struct file *f, char __user *buf,
break;

r = put_user(*(rd_buf + result), buf);
- if (r)
+ if (r) {
+ kfree(rd_buf);
return r; /* r = -EFAULT */
+ }

buf += 1;
size -= 1;
@@ -2174,8 +2202,10 @@ static ssize_t dp_dsc_chunk_size_read(struct file *f, char __user *buf,
break;
}

- if (!pipe_ctx)
+ if (!pipe_ctx) {
+ kfree(rd_buf);
return -ENXIO;
+ }

dsc = pipe_ctx->stream_res.dsc;
if (dsc)
@@ -2191,8 +2221,10 @@ static ssize_t dp_dsc_chunk_size_read(struct file *f, char __user *buf,
break;

r = put_user(*(rd_buf + result), buf);
- if (r)
+ if (r) {
+ kfree(rd_buf);
return r; /* r = -EFAULT */
+ }

buf += 1;
size -= 1;
@@ -2246,8 +2278,10 @@ static ssize_t dp_dsc_slice_bpg_offset_read(struct file *f, char __user *buf,
break;
}

- if (!pipe_ctx)
+ if (!pipe_ctx) {
+ kfree(rd_buf);
return -ENXIO;
+ }

dsc = pipe_ctx->stream_res.dsc;
if (dsc)
@@ -2263,8 +2297,10 @@ static ssize_t dp_dsc_slice_bpg_offset_read(struct file *f, char __user *buf,
break;

r = put_user(*(rd_buf + result), buf);
- if (r)
+ if (r) {
+ kfree(rd_buf);
return r; /* r = -EFAULT */
+ }

buf += 1;
size -= 1;
@@ -3254,8 +3290,10 @@ static ssize_t dcc_en_bits_read(
dc->hwss.get_dcc_en_bits(dc, dcc_en_bits);

rd_buf = kcalloc(rd_buf_size, sizeof(char), GFP_KERNEL);
- if (!rd_buf)
+ if (!rd_buf) {
+ kfree(dcc_en_bits);
return -ENOMEM;
+ }

for (i = 0; i < num_pipes; i++)
offset += snprintf(rd_buf + offset, rd_buf_size - offset,
@@ -3268,8 +3306,10 @@ static ssize_t dcc_en_bits_read(
if (*pos >= rd_buf_size)
break;
r = put_user(*(rd_buf + result), buf);
- if (r)
+ if (r) {
+ kfree(rd_buf);
return r; /* r = -EFAULT */
+ }
buf += 1;
size -= 1;
*pos += 1;
--
2.35.1