[PATCH 5.10 009/306] blk-zoned: allow zone management send operations without CAP_SYS_ADMIN

[Greg Kroah-Hartman]

From: Niklas Cassel <niklas.cassel@xxxxxxx>

commit ead3b768bb51259e3a5f2287ff5fc9041eb6f450 upstream.

Zone management send operations (BLKRESETZONE, BLKOPENZONE, BLKCLOSEZONE
and BLKFINISHZONE) should be allowed under the same permissions as write().
(write() does not require CAP_SYS_ADMIN).

Additionally, other ioctls like BLKSECDISCARD and BLKZEROOUT only check if
the fd was successfully opened with FMODE_WRITE.
(They do not require CAP_SYS_ADMIN).

Currently, zone management send operations require both CAP_SYS_ADMIN
and that the fd was successfully opened with FMODE_WRITE.

Remove the CAP_SYS_ADMIN requirement, so that zone management send
operations match the access control requirement of write(), BLKSECDISCARD
and BLKZEROOUT.

Fixes: 3ed05a987e0f ("blk-zoned: implement ioctls")
Signed-off-by: Niklas Cassel <niklas.cassel@xxxxxxx>
Reviewed-by: Damien Le Moal <damien.lemoal@xxxxxxx>
Reviewed-by: Aravind Ramesh <aravind.ramesh@xxxxxxx>
Reviewed-by: Adam Manzanares <a.manzanares@xxxxxxxxxxx>
Reviewed-by: Himanshu Madhani <himanshu.madhani@xxxxxxxxxx>
Reviewed-by: Johannes Thumshirn <johannes.thumshirn@xxxxxxx>
Cc: stable@xxxxxxxxxxxxxxx # v4.10+
Link: https://lore.kernel.org/r/20210811110505.29649-2-Niklas.Cassel@xxxxxxx
Signed-off-by: Jens Axboe <axboe@xxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
 block/blk-zoned.c |    3 ---
 1 file changed, 3 deletions(-)

--- a/block/blk-zoned.c
+++ b/block/blk-zoned.c
@@ -357,9 +357,6 @@ int blkdev_zone_mgmt_ioctl(struct block_
 	if (!blk_queue_is_zoned(q))
 		return -ENOTTY;
 
-	if (!capable(CAP_SYS_ADMIN))
-		return -EACCES;
-
 	if (!(mode & FMODE_WRITE))
 		return -EBADF;