Re: Fwd: [PATCH] Size can be any value and is user controlled resulting in overwriting the 40 byte array wr_buf with an arbitrary length of data from buf.

[Christian König]

Am 11.10.21 um 22:24 schrieb T. Williams:


---------- Forwarded message ---------
From: *docfate111* <tdwilliam...@gmail.com 
<mailto:tdwilliam...@gmail.com>>
Date: Mon, Oct 11, 2021 at 4:22 PM
Subject: [PATCH] Size can be any value and is user controlled 
resulting in overwriting the 40 byte array wr_buf with an arbitrary 
length of data from buf.
To: <dri-de...@lists.freedesktop.org 
<mailto:dri-de...@lists.freedesktop.org>>
Cc: <harry.wentl...@amd.com <mailto:harry.wentl...@amd.com>>, 
<sunpeng...@amd.com <mailto:sunpeng...@amd.com>>


Signed-off-by: docfate111 <tdwilliam...@gmail.com 
<mailto:tdwilliam...@gmail.com>>

While the find might be correct there are a couple of style problems 
with the patch.

First of all the subject line must be shorter and should be something 
like "drm/amdgpu: fix out of bounds write".

The detailed description of the bug then comes into the commit message.

And finally please use your real name for the Signed-off-by line.

Apart from that good catch,
Christian.

---
 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 87daa78a32b8..17f2756a64dc 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
@@ -263,7 +263,7 @@ static ssize_t dp_link_settings_write(struct file 
*f, const char __user *buf,
        if (!wr_buf)
                return -ENOSPC;

-       if (parse_write_buffer_into_params(wr_buf, size,
+       if (parse_write_buffer_into_params(wr_buf, wr_buf_size,
                                           (long *)param, buf,
                                           max_param_num,
                                           &param_nums)) {
--
2.25.1



--
Thank you for your time,
Thelford Williams