linux-kernel - Re: [PATCH] scsi: core: initialize cmd->cmnd before it is used

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

Message-ID: <4cfa4049-aae5-51db-4ad2-b4c9db996525@acm.org>
Date:   Mon, 1 Nov 2021 13:06:16 -0700
From:   Bart Van Assche <bvanassche@....org>
To:     Tadeusz Struk <tadeusz.struk@...aro.org>,
        linux-scsi@...r.kernel.org
Cc:     Christoph Hellwig <hch@....de>,
        "James E . J . Bottomley" <jejb@...ux.ibm.com>,
        "Martin K . Petersen" <martin.petersen@...cle.com>,
        linux-kernel@...r.kernel.org, stable@...r.kernel.org,
        syzbot+5516b30f5401d4dcbcae@...kaller.appspotmail.com
Subject: Re: [PATCH] scsi: core: initialize cmd->cmnd before it is used

On 11/1/21 12:24 PM, Tadeusz Struk wrote:
> diff --git a/drivers/scsi/scsi_lib.c b/drivers/scsi/scsi_lib.c
> index 572673873ddf..cd4b57747448 100644
> --- a/drivers/scsi/scsi_lib.c
> +++ b/drivers/scsi/scsi_lib.c
> @@ -1173,10 +1173,10 @@ static blk_status_t scsi_setup_scsi_cmnd(struct scsi_device *sdev,
>   		memset(&cmd->sdb, 0, sizeof(cmd->sdb));
>   	}
>   
> +	cmd->cmnd = scsi_req(req)->cmd;
>   	cmd->cmd_len = scsi_req(req)->cmd_len;
>   	if (cmd->cmd_len == 0)
>   		cmd->cmd_len = scsi_command_size(cmd->cmnd);
> -	cmd->cmnd = scsi_req(req)->cmd;
>   	cmd->transfersize = blk_rq_bytes(req);
>   	cmd->allowed = scsi_req(req)->retries;
>   	return BLK_STS_OK;

This patch is a duplicate and has been posted before.

Please take a look at https://lore.kernel.org/linux-scsi/20210904064534.1919476-1-qiulaibin@huawei.com/.
 From the replies to that email:
"> Thinking further about this: is there any code left that depends on
 > scsi_setup_scsi_cmnd() setting cmd->cmd_len? Can the cmd->cmd_len
 > assignment be removed from scsi_setup_scsi_cmnd()?

cmd_len should never be 0 now, so I think we can remove it."

Thanks,

Bart.