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To: Todd Poynor <toddpoynor@google.com>
Cc: Doug Gilbert <dgilbert@interlog.com>,
        "James E.J. Bottomley" <jejb@linux.vnet.ibm.com>,
        "Martin K. Petersen" <martin.petersen@oracle.com>,
        linux-scsi@vger.kernel.org, linux-kernel@vger.kernel.org,
        Hannes Reinecke <hare@suse.de>
Subject: Re: [PATCH] sg: protect against races between mmap() and SG_SET_RESERVED_SIZE
From: "Martin K. Petersen" <martin.petersen@oracle.com>
Organization: Oracle Corporation
References: <20170816054108.119890-1-toddpoynor@google.com>
Date: Tue, 22 Aug 2017 22:21:06 -0400
In-Reply-To: <20170816054108.119890-1-toddpoynor@google.com> (Todd Poynor's
        message of "Tue, 15 Aug 2017 22:41:08 -0700")
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Todd,

> Take f_mutex around mmap() processing to protect against races with
> the SG_SET_RESERVED_SIZE ioctl.  Ensure the reserve buffer length
> remains consistent during the mapping operation, and set the
> "mmap called" flag to prevent further changes to the reserved buffer
> size as an atomic operation with the mapping.

Applied to 4.14/scsi-queue (with a slight whitespace fix). Thanks!

-- 
Martin K. Petersen	Oracle Linux Engineering