[Public]


Applied.  Thanks!

From: Wentland, Harry <Harry.Wentland@amd.com>
Sent: Friday, January 21, 2022 2:03 PM
To: Yongzhi Liu <lyz_cs@pku.edu.cn>; Li, Sun peng (Leo) <Sunpeng.Li@amd.com>; Siqueira, Rodrigo <Rodrigo.Siqueira@amd.com>; Deucher, Alexander <Alexander.Deucher@amd.com>; Koenig, Christian <Christian.Koenig@amd.com>; Pan, Xinhui <Xinhui.Pan@amd.com>; airlied@linux.ie <airlied@linux.ie>; daniel@ffwll.ch <daniel@ffwll.ch>; Lipski, Mikita <Mikita.Lipski@amd.com>; Lin, Wayne <Wayne.Lin@amd.com>; Kazlauskas, Nicholas <Nicholas.Kazlauskas@amd.com>; Zuo, Jerry <Jerry.Zuo@amd.com>; Anson.Jacob@amd.com <Anson.Jacob@amd.com>; eryk.brol@amd.com <eryk.brol@amd.com>; Pillai, Aurabindo <Aurabindo.Pillai@amd.com>; Das, Nirmoy <Nirmoy.Das@amd.com>
Cc: amd-gfx@lists.freedesktop.org <amd-gfx@lists.freedesktop.org>; dri-devel@lists.freedesktop.org <dri-devel@lists.freedesktop.org>; linux-kernel@vger.kernel.org <linux-kernel@vger.kernel.org>
Subject: Re: [PATCH] drm/amd/display: Fix memory leak
 
On 2022-01-21 06:26, Yongzhi Liu wrote:
> [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.
>
> Signed-off-by: Yongzhi Liu <lyz_cs@pku.edu.cn>

Reviewed-by: Harry Wentland <harry.wentland@amd.com>

Harry

> ---
>  .../drm/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 ded64d0..e463d46 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
> @@ -227,8 +227,10 @@ 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;
> @@ -389,8 +391,10 @@ 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;
> @@ -1359,8 +1363,10 @@ 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)
> @@ -1376,8 +1382,10 @@ 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;
> @@ -1546,8 +1554,10 @@ 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)
> @@ -1563,8 +1573,10 @@ 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;
> @@ -1731,8 +1743,10 @@ 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)
> @@ -1748,8 +1762,10 @@ 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;
> @@ -1912,8 +1928,10 @@ 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)
> @@ -1929,8 +1947,10 @@ 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;
> @@ -2088,8 +2108,10 @@ 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)
> @@ -2105,8 +2127,10 @@ 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;
> @@ -2145,8 +2169,10 @@ 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)
> @@ -2162,8 +2188,10 @@ 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;
> @@ -2217,8 +2245,10 @@ 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)
> @@ -2234,8 +2264,10 @@ 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;
> @@ -2289,8 +2321,10 @@ 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)
> @@ -2306,8 +2340,10 @@ 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;
> @@ -3459,8 +3495,10 @@ 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,
> @@ -3473,8 +3511,10 @@ 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;