linux-kernel - Re: [PATCH v8 1/1] smb: move FILE_SYSTEM_ATTRIBUTE

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [day] [month] [year] [list]

Message-ID: <d7a7ce57-f486-491e-9002-cc8cfc115521@linux.dev>
Date: Mon, 17 Nov 2025 09:06:15 +0800
From: ChenXiaoSong <chenxiaosong.chenxiaosong@...ux.dev>
To: Namjae Jeon <linkinjeon@...nel.org>
Cc: sfrench@...ba.org, smfrench@...il.com, linkinjeon@...ba.org,
 christophe.jaillet@...adoo.fr, linux-cifs@...r.kernel.org,
 linux-kernel@...r.kernel.org, chenxiaosong@...nxiaosong.com
Subject: Re: [PATCH v8 1/1] smb: move FILE_SYSTEM_ATTRIBUTE_INFO to
 common/fscc.h

Hi Namjae,

I have confirmed that when FileSystemName uses flexible array member, 
fsAttrInfo in struct cifs_tcon does not include FileSystemName.

The following part in the CIFSSMBQFSAttributeInfo() function is correct, 
we cannot add MAX_FS_NAME_LEN to sizeof(FILE_SYSTEM_ATTRIBUTE_INFO).

```c
CIFSSMBQFSAttributeInfo()
{
...
     memcpy(&tcon->fsAttrInfo, response_data,
         sizeof(FILE_SYSTEM_ATTRIBUTE_INFO)); // it's correct here
...
}
```

And in the following part of the SMB2_QFS_attr() function, we should 
change it to `memcpy(..., min_t(..., min_len))`.

```c
SMB2_QFS_attr()
{
...
     if (level == FS_ATTRIBUTE_INFORMATION)
             memcpy(&tcon->fsAttrInfo, offset
                     + (char *)rsp, min_t(unsigned int,
                     rsp_len, max_len)); // should use `min_len` here
...
}
```

Thanks,
ChenXiaoSong.

On 11/17/25 07:00, Namjae Jeon wrote:

> Did you check if it is being used here too?
> cifssmb.c:4866:        sizeof(FILE_SYSTEM_ATTRIBUTE_INFO));