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Message-ID: <9c96f82e-000b-88f8-fa37-753ed6723119@intel.com>
Date: Tue, 15 Nov 2022 16:48:40 -0800
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Subject: Re: [PATCH 1/2] scsi: Fix get_user() in call sg_scsi_ioctl()
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To: "Kirill A. Shutemov" <kirill.shutemov@linux.intel.com>,
 kirill@shutemov.name
Cc: dave.hansen@linux.intel.com, jejb@linux.ibm.com,
 linux-kernel@vger.kernel.org, lkp@intel.com, martin.petersen@oracle.com,
 oe-kbuild-all@lists.linux.dev, x86@kernel.org
References: <20221115155802.p3vjnk7eqqcyskt3@box.shutemov.name>
 <20221116004353.15052-1-kirill.shutemov@linux.intel.com>
 <20221116004353.15052-2-kirill.shutemov@linux.intel.com>
From: Dave Hansen <dave.hansen@intel.com>
In-Reply-To: <20221116004353.15052-2-kirill.shutemov@linux.intel.com>
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On 11/15/22 16:43, Kirill A. Shutemov wrote:
> get_user() expects the pointer to be pointer-to-simple-variable type,
> but sic->data is array of 'unsigned char'. It violates get_user()
> contracts.
> 
> Cast it explicitly to 'unsigned char __user *'. It matches current
> behaviour.
> 
> This is preparation for fixing sparse warnings caused by Linear Address
> Masking patchset.

What's the side-effect if this isn't applied?  Is it worse than sparse
warnings?