linux-kernel - Re: [PATCH 22/30] cifs: Use kmemdup rather than duplicating its implementation

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]

Date:   Wed, 3 Jul 2019 15:16:46 -0500
From:   Steve French <smfrench@...il.com>
To:     Fuqian Huang <huangfq.daxian@...il.com>
Cc:     Steve French <sfrench@...ba.org>,
        CIFS <linux-cifs@...r.kernel.org>,
        samba-technical <samba-technical@...ts.samba.org>,
        LKML <linux-kernel@...r.kernel.org>
Subject: Re: [PATCH 22/30] cifs: Use kmemdup rather than duplicating its implementation

Looks like this was already merged

commit c8fc464cbda384ba4ed48c1e744ca82cd69f1f93
Author: YueHaibing <yuehaibing@...wei.com>
Date:   Sat Jun 1 03:31:10 2019 +0000

    cifs: Use kmemdup in SMB2_ioctl_init()

    Use kmemdup rather than duplicating its implementation

    This was reported by coccinelle.

    Signed-off-by: YueHaibing <yuehaibing@...wei.com>
    Signed-off-by: Steve French <stfrench@...rosoft.com>

diff --git a/fs/cifs/smb2pdu.c b/fs/cifs/smb2pdu.c
index 75311a8a68bf..ab8dc73d2282 100644
--- a/fs/cifs/smb2pdu.c
+++ b/fs/cifs/smb2pdu.c
@@ -2550,12 +2550,11 @@ SMB2_ioctl_init(struct cifs_tcon *tcon, struct
smb_rqst *rqst,
                 * indatalen is usually small at a couple of bytes max, so
                 * just allocate through generic pool
                 */
-               in_data_buf = kmalloc(indatalen, GFP_NOFS);
+               in_data_buf = kmemdup(in_data, indatalen, GFP_NOFS);
                if (!in_data_buf) {
                        cifs_small_buf_release(req);
                        return -ENOMEM;
                }
-               memcpy(in_data_buf, in_data, indatalen);
        }

        req->CtlCode = cpu_to_le32(opcode);

On Wed, Jul 3, 2019 at 8:18 AM Fuqian Huang <huangfq.daxian@...il.com> wrote:
>
> kmemdup is introduced to duplicate a region of memory in a neat way.
> Rather than kmalloc/kzalloc + memset, which the programmer needs to
> write the size twice (sometimes lead to mistakes), kmemdup improves
> readability, leads to smaller code and also reduce the chances of mistakes.
> Suggestion to use kmemdup rather than using kmalloc/kzalloc + memset.
>
> Signed-off-by: Fuqian Huang <huangfq.daxian@...il.com>
> ---
>  fs/cifs/smb2pdu.c | 3 +--
>  1 file changed, 1 insertion(+), 2 deletions(-)
>
> diff --git a/fs/cifs/smb2pdu.c b/fs/cifs/smb2pdu.c
> index 75311a8a68bf..ab8dc73d2282 100644
> --- a/fs/cifs/smb2pdu.c
> +++ b/fs/cifs/smb2pdu.c
> @@ -2550,12 +2550,11 @@ SMB2_ioctl_init(struct cifs_tcon *tcon, struct smb_rqst *rqst,
>                  * indatalen is usually small at a couple of bytes max, so
>                  * just allocate through generic pool
>                  */
> -               in_data_buf = kmalloc(indatalen, GFP_NOFS);
> +               in_data_buf = kmemdup(in_data, indatalen, GFP_NOFS);
>                 if (!in_data_buf) {
>                         cifs_small_buf_release(req);
>                         return -ENOMEM;
>                 }
> -               memcpy(in_data_buf, in_data, indatalen);
>         }
>
>         req->CtlCode = cpu_to_le32(opcode);
> --
> 2.11.0
>


-- 
Thanks,

Steve