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 <ckoenig.leichtzumerken@xxxxxxxxx>]

    Am 11.10.21 um 22:24 schrieb T. Williams:

---------- Forwarded message ---------
From: docfate111 <tdwilliamsiv@xxxxxxxxx>
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-devel@xxxxxxxxxxxxxxxxxxxxx>
Cc: <harry.wentland@xxxxxxx>, <sunpeng.li@xxxxxxx>

Signed-off-by: docfate111 <tdwilliamsiv@xxxxxxxxx>

    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