Received-SPF: pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 23.128.96.18 as permitted sender) client-ip=23.128.96.18;
IronPort-SDR: ldjpW0tAoS6f3szGLnVqrAkkgK1CpVwffkCZcK52jkSi8qr17aBEp9VswHG0OIDNkE5J3AVU39
 fpBqgU1bxkR92XEDo7SR9tWTAIdm5zqXIfIwdJHsv2BabY9fgJMrtlkJdJfUTJ4ADjPcx1GOi7
 ilRixybwTNZuXXEgdyk2arI2Fw6sZ94XbKF+khKUGcCA/4K9Cqq1ikosz4vPTMLWn43K/w9aJw
 OxAummh1LLUeZQlZB5/e5C9OWYkbDedqVaR1p6g0g+YL0XST7npeJSItCoDUXLAJ9hWAnl35Yk
 0tU=
From:   Niklas Cassel <Niklas.Cassel@wdc.com>
To:     Jens Axboe <axboe@kernel.dk>,
        Damien Le Moal <Damien.LeMoal@wdc.com>,
        Shaun Tancheff <shaun@tancheff.com>,
        "Martin K. Petersen" <martin.petersen@oracle.com>,
        Hannes Reinecke <hare@suse.com>
CC:     Damien Le Moal <Damien.LeMoal@wdc.com>,
        Niklas Cassel <Niklas.Cassel@wdc.com>,
        "stable@vger.kernel.org" <stable@vger.kernel.org>,
        Jens Axboe <axboe@fb.com>,
        "linux-block@vger.kernel.org" <linux-block@vger.kernel.org>,
        "linux-kernel@vger.kernel.org" <linux-kernel@vger.kernel.org>
Subject: [PATCH v2 2/2] blk-zoned: allow BLKREPORTZONE without CAP_SYS_ADMIN
Thread-Topic: [PATCH v2 2/2] blk-zoned: allow BLKREPORTZONE without
 CAP_SYS_ADMIN
Thread-Index: AQHXVsGgyVhYWBzsdE+J29N7kj8+jQ==
Date:   Tue, 1 Jun 2021 08:39:25 +0000
Message-ID: <20210601083915.156476-3-Niklas.Cassel@wdc.com>
References: <20210601083915.156476-1-Niklas.Cassel@wdc.com>
In-Reply-To: <20210601083915.156476-1-Niklas.Cassel@wdc.com>
Accept-Language: en-US
Content-Language: en-US
wdcipoutbound: EOP-TRUE
Content-Type: text/plain; charset="iso-8859-1"
Content-Transfer-Encoding: quoted-printable
MIME-Version: 1.0
X-MS-Exchange-CrossTenant-Network-Message-Id: 86975a09-efc9-406a-fda9-08d924d8c4f0
X-MS-Exchange-CrossTenant-originalarrivaltime: 01 Jun 2021 08:39:25.9642
 (UTC)
X-MS-Exchange-CrossTenant-fromentityheader: Hosted
X-MS-Exchange-CrossTenant-id: b61c8803-16f3-4c35-9b17-6f65f441df86
X-MS-Exchange-CrossTenant-mailboxtype: HOSTED
X-MS-Exchange-CrossTenant-userprincipalname: jM3vC04ByR1H9a6zZa8nv1297ndDm9Q0nunnKOQtVqu74pzWbVgE+PdviZjHDs0MVtouyG9UJds+t1aWDVkmhA==
X-MS-Exchange-Transport-CrossTenantHeadersStamped: PH0PR04MB7317
Precedence: bulk
List-ID: <linux-kernel.vger.kernel.org>
X-Mailing-List: linux-kernel@vger.kernel.org

From: Niklas Cassel <niklas.cassel@wdc.com>

Performing a BLKREPORTZONE operation should be allowed under the same
permissions as read(). (read() does not require CAP_SYS_ADMIN).

Remove the CAP_SYS_ADMIN requirement, and instead check that the fd was
successfully opened with FMODE_READ. This way BLKREPORTZONE will match
the access control requirement of read().

Fixes: 3ed05a987e0f ("blk-zoned: implement ioctls")
Signed-off-by: Niklas Cassel <niklas.cassel@wdc.com>
Reviewed-by: Damien Le Moal <damien.lemoal@wdc.com>
Cc: stable@vger.kernel.org # v4.10+
---
Changes since v1:
- Pick up tag from Damien.
- Add fixes tag and CC stable.

 block/blk-zoned.c | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/block/blk-zoned.c b/block/blk-zoned.c
index 0789e6e9f7db..e05fe8dbb06d 100644
--- a/block/blk-zoned.c
+++ b/block/blk-zoned.c
@@ -288,8 +288,8 @@ int blkdev_report_zones_ioctl(struct block_device *bdev=
, fmode_t mode,
 	if (!blk_queue_is_zoned(q))
 		return -ENOTTY;
=20
-	if (!capable(CAP_SYS_ADMIN))
-		return -EACCES;
+	if (!(mode & FMODE_READ))
+		return -EBADF;
=20
 	if (copy_from_user(&rep, argp, sizeof(struct blk_zone_report)))
 		return -EFAULT;
--=20
2.31.1