linux-kernel - Re: [PATCH] scsi: Let scsi_execute_cmd() mark args->sshdr as invalid

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: <554bfa20-2228-8655-09e2-492cbfa183fa@oracle.com>
Date:   Fri, 19 May 2023 17:06:03 +0100
From:   John Garry <john.g.garry@...cle.com>
To:     Bart Van Assche <bvanassche@....org>,
        Juergen Gross <jgross@...e.com>,
        "Martin K. Petersen" <martin.petersen@...cle.com>
Cc:     linux-kernel@...r.kernel.org, linux-scsi@...r.kernel.org,
        "James E.J. Bottomley" <jejb@...ux.ibm.com>, stable@...r.kernel.org
Subject: Re: [PATCH] scsi: Let scsi_execute_cmd() mark args->sshdr as invalid

On 18/05/2023 20:54, Bart Van Assche wrote:
> 
>> Further to that, I dislike how we pass a pointer to this local sshdr 
>> structure. I would prefer if scsi_execute_cmd() could kmalloc() the 
>> mem for these buffers and the callers could handle free'ing them - I 
>> can put together a patch for that, to see what people think.
> 
> sizeof(struct scsi_sense_hdr) = 8. Using kmalloc() to allocate an eight 
> byte data structure sounds like overkill to me. Additionally, making 
> scsi_execute_cmd() allocate struct scsi_sense_hdr and letting the 
> callers free that data structure will make it harder to review whether 
> or not any memory leaks are triggered. No such review is necessary if 
> the scsi_execute_cmd() caller allocates that data structure on the stack.

Sure, what I describe is ideal, but I still just dislike passing both 
sensebuf and hdr into scsi_execute_cmd(). The semantics of how 
scsi_execute_cmd() treats them is vague.

Thanks,
John