To:     Kees Cook <keescook@chromium.org>
Cc:     James Smart <james.smart@broadcom.com>,
        Dick Kennedy <dick.kennedy@broadcom.com>,
        "James E.J. Bottomley" <jejb@linux.ibm.com>,
        "Martin K. Petersen" <martin.petersen@oracle.com>,
        linux-kernel@vger.kernel.org, linux-scsi@vger.kernel.org,
        linux-hardening@vger.kernel.org
Subject: Re: [PATCH] scsi: lpfc: Use struct_group to isolate cast to larger
 object
From:   "Martin K. Petersen" <martin.petersen@oracle.com>
Organization: Oracle Corporation
Message-ID: <yq1sfuvolhk.fsf@ca-mkp.ca.oracle.com>
References: <20211203223351.107323-1-keescook@chromium.org>
Date:   Mon, 13 Dec 2021 23:31:59 -0500
In-Reply-To: <20211203223351.107323-1-keescook@chromium.org> (Kees Cook's
        message of "Fri, 3 Dec 2021 14:33:51 -0800")
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Kees,

> When building under -Warray-bounds, a warning is generated when casting
> a u32 into MAILBOX_t (which is larger). This warning is conservative, but
> it's not an unreasonable change to make to improve future robustness. Use
> a tagged struct_group that can refer to either the specific fields or
> the first u32 separately, silencing this warning:

Applied to 5.17/scsi-staging, thanks!

-- 
Martin K. Petersen	Oracle Linux Engineering