Received-SPF: pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 2620:137:e000::1:20 as permitted sender) client-ip=2620:137:e000::1:20;
Subject: Re: [PATCH] scsi: myrs: check return value of dma_alloc_coherent()
 instead of using dma_mapping_error()
To:     Peter Kosyh <pkosyh@yandex.ru>, Hannes Reinecke <hare@kernel.org>
Cc:     lvc-project@linuxtesting.org,
        "Martin K. Petersen" <martin.petersen@oracle.com>,
        "James E.J. Bottomley" <jejb@linux.ibm.com>,
        linux-kernel@vger.kernel.org, linux-scsi@vger.kernel.org
References: <20221116094147.221640-1-pkosyh@yandex.ru>
From:   Alexey Khoroshilov <khoroshilov@ispras.ru>
Autocrypt: addr=khoroshilov@ispras.ru; prefer-encrypt=mutual; keydata=
 xsFNBFtq9eIBEACxmOIPDht+aZvO9DGi4TwnZ1WTDnyDVz3Nnh0rlQCK8IssaT6wE5a95VWo
 iwOWalcL9bJMHQvw60JwZKFjt9oH2bov3xzx/JRCISQB4a4U1J/scWvPtabbB3t+VAodF5KZ
 vZ2gu/Q/Wa5JZ9aBH0IvNpBAAThFg1rBXKh7wNqrhsQlMLg+zTSK6ZctddNl6RyaJvAmbaTS
 sSeyUKXiabxHn3BR9jclXfmPLfWuayinBvW4J3vS+bOhbLxeu3MO0dUqeX/Nl8EAhvzo0I2d
 A0vRu/Ze1wU3EQYT6M8z3i1b3pdLjr/i+MI8Rgijs+TFRAhxRw/+0vHGTg6Pn02t0XkycxQR
 mhH3v0kVTvMyM7YSI7yXvd0QPxb1RX9AGmvbJu7eylzcq9Jla+/T3pOuWsJkbvbvuFKKmmYY
 WnAOR7vu/VNVfiy4rM0bfO14cIuEG+yvogcPuMmQGYu6ZwS9IdgZIOAkO57M/6wR0jIyfxrG
 FV3ietPtVcqeDVrcShKyziRLJ+Xcsg9BLdnImAqVQomYr27pyNMRL5ILuT7uOuAQPDKBksK+
 l2Fws0d5iUifqnXSPuYxqgS4f8SQLS7ECxvCGVVbkEEng9vkkmyrF6wM86BZ9apPGDFbopiK
 7GRxQtSGszVv83abaVb8aDsAudJIp7lLaIuXLZAe1r+ycYpEtQARAQABzSpBbGV4ZXkgS2hv
 cm9zaGlsb3YgPGtob3Jvc2hpbG92QGlzcHJhcy5ydT7CwX0EEwEIACcFAltq9eICGwMFCRLM
 AwAFCwkIBwIGFQgJCgsCBBYCAwECHgECF4AACgkQ2B/JSzCwrEWLaA/+NFZfyhU0vJzFtYsk
 yaqx8nWZLrAoUK7VcobH0lJH6lfGbarO5JpENaIiTP12YZ4xO+j3GGJtLy2gvnpypGnxmiAl
 RqPt7WeAIj6oqPrUs2QF7i4SOiPtku/NrysI1zHzlA8yqUduBtam5rdQeLRNCJiEED1fU8sp
 +DgJBN/OHEDyAag2hu1KFKWuPfQ+QGpXYZb+1NW/hKwvvwCNVyypELAfFnkketFXjIMwHnL8
 ZPqJZlkvkpxuRXOaXPL9NFhZnC/WS+NJ81L3pr+w6eo3xTPYZvRW8glvqlEDgHqr3uMGIaes
 nwfRXLHp+TC1ht6efCXzdPyMZ1E7HXQN9foKisI1V5iQFhN+CT3dbsguQI4e10F5ql0TZUJY
 SMzvY0eObs6TWRdD/Ha7Y5rLmZ54R9sxumpZNcJzktfgm9f0XfeqVEJUn/40MRDD+l2W12Db
 Jkko+sbtAEw+f+/j3uz8xOE+Uv4kwFC5a6JKgdX88oigHnpAs3FvffP594Loi3ibFrQUW5wH
 bXh5Ni+l1GKEQ0PHMk+KQQT9L2r9s7C0Nh8XzwdpOshZWsrNSZqcG+01wrmUhyX2uSaoZ07I
 /+KZURlMSqI71X6lkMWlB3SyThvYhHgnR0EGGTerwM1MaVjHN+Z6lPmsKNxG8lzCeWeZ6peA
 c5oUHV4WQ8Ux9BM8saLOwU0EW2r14gEQAMz+5u+X7j1/dT4WLVRQaE1Shnd2dKBn2E7fgo/N
 4JIY6wHD/DJoWYQpCJjjvBYSonvQsHicvDW8lPh2EXgZ9Fi8AHKT2mVPitVy+uhfWa/0FtsC
 e3hPfrjTcN7BUcXlIjmptxIoDbvQrNfIWUGdWiyDj4EDfABW/kagXqaBwF2HdcDaNDGggD1c
 DglA0APjezIyTGnGMKsi5QSSlOLm8OZEJMj5t+JL6QXrruijNb5Asmz5mpRQrak7DpGOskjK
 fClm/0oy2zDvWuoXJa+dm3YFr43V+c5EIMA4LpGk63Eg+5NltQ/gj0ycgD5o6reCbjLz4R9D
 JzBezK/KOQuNG5qKUTMbOHWaApZnZ6BDdOVflkV1V+LMo5GvIzkATNLm/7Jj6DmYmXbKoSAY
 BKZiJWqzNsL1AJtmJA1y5zbWX/W4CpNs8qYMYG8eTNOqunzopEhX7T0cOswcTGArZYygiwDW
 BuIS83QRc7udMlQg79qyMA5WqS9g9g/iodlssR9weIVoZSjfjhm5NJ3FmaKnb56h6DSvFgsH
 xCa4s1DGnZGSAtedj8E3ACOsEfu4J/WqXEmvMYNBdGos2YAc+g0hjuOB10BSD98d38xP1vPc
 qNrztIF+TODAl1dNwU4rCSdGQymsrMVFuXnHMH4G+dHvMAwWauzDbnILHAGFyJtfxVefABEB
 AAHCwWUEGAEIAA8FAltq9eICGwwFCRLMAwAACgkQ2B/JSzCwrEU3Rg//eFWHXqTQ5CKw4KrX
 kTFxdXnYKJ5zZB0EzqU6m/FAV7snmygFLbOXYlcMW2Fh306ivj9NKJrlOaPbUzzyDf8dtDAg
 nSbH156oNJ9NHkz0mrxFMpJA2E5AUemOFx57PUYt93pR2B7bF2zGua4gMC+vorDQZjX9kvrL
 Kbenh3boFOe1tUaiRRvEltVFLOg+b+CMkKVbLIQe/HkyKJH5MFiHAF7QxnPHaxyO7QbWaUmF
 6BHVujxAGvNgkrYJb6dpiNNZSFNRodaSToU5oM+z1dCrNNtN3u4R7AYr6DDIDxoSzR4k0ZaG
 uSeqh4xxQCD7vLT3JdZDyhYUJgy9mvSXdkXGdBIhVmeLch2gaWNf5UOutVJwdPbIaUDRjVoV
 Iw6qjKq+mnK3ttuxW5Aeg9Y1OuKEvCVu+U/iEEJxx1JRmVAYq848YqtVPY9DkZdBT4E9dHqO
 n8lr+XPVyMN6SBXkaR5tB6zSkSDrIw+9uv1LN7QIri43fLqhM950ltlveROEdLL1bI30lYO5
 J07KmxgOjrvY8X9WOC3O0k/nFpBbbsM4zUrmF6F5wIYO99xafQOlfpUnVtbo3GnBR2LIcPYj
 SyY3dW28JXo2cftxIOr1edJ+fhcRqYRrPzJrQBZcE2GZjRO8tz6IOMAsc+WMtVfj5grgVHCu
 kK2E04Fb+Zk1eJvHYRc=
Message-ID: <d87d208b-5fc7-8675-e07a-69c7665b32e5@ispras.ru>
Date:   Thu, 20 Apr 2023 22:02:57 +0300
User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:68.0) Gecko/20100101
 Thunderbird/68.10.0
MIME-Version: 1.0
In-Reply-To: <20221116094147.221640-1-pkosyh@yandex.ru>
Content-Type: text/plain; charset=utf-8
Content-Language: ru-RU
Content-Transfer-Encoding: 7bit
Precedence: bulk

On 16.11.2022 12:41, Peter Kosyh wrote:
> dma_alloc_coherent() may leave third parameter uninitialized. So
> it is not safe to use dma_mapping_error() without checking return
> value of dma_alloc_coherent().
> 
> Check the return value of dma_alloc_coherent() to detect
> an error.
> 
> Found by Linux Verification Center (linuxtesting.org) with SVACE.
> 
> Signed-off-by: Peter Kosyh <pkosyh@yandex.ru>
> ---
>  drivers/scsi/myrs.c | 4 ++--
>  1 file changed, 2 insertions(+), 2 deletions(-)
> 
> diff --git a/drivers/scsi/myrs.c b/drivers/scsi/myrs.c
> index 7eb8c39da366..1811c1a6385b 100644
> --- a/drivers/scsi/myrs.c
> +++ b/drivers/scsi/myrs.c
> @@ -498,14 +498,14 @@ static bool myrs_enable_mmio_mbox(struct myrs_hba *cs,
>  	/* Temporary dma mapping, used only in the scope of this function */
>  	mbox = dma_alloc_coherent(&pdev->dev, sizeof(union myrs_cmd_mbox),
>  				  &mbox_addr, GFP_KERNEL);
> -	if (dma_mapping_error(&pdev->dev, mbox_addr))
> +	if (!mbox)
>  		return false;
>  
>  	/* These are the base addresses for the command memory mailbox array */
>  	cs->cmd_mbox_size = MYRS_MAX_CMD_MBOX * sizeof(union myrs_cmd_mbox);
>  	cmd_mbox = dma_alloc_coherent(&pdev->dev, cs->cmd_mbox_size,
>  				      &cs->cmd_mbox_addr, GFP_KERNEL);
> -	if (dma_mapping_error(&pdev->dev, cs->cmd_mbox_addr)) {
> +	if (!cmd_mbox) {
>  		dev_err(&pdev->dev, "Failed to map command mailbox\n");
>  		goto out_free;
>  	}
> 

Reviewed-by: Alexey Khoroshilov <khoroshilov@ispras.ru>

Also you may want to add
Fixes: 77266186397c ("scsi: myrs: Add Mylex RAID controller (SCSI
interface)")

--
Alexey