[Devel] [PATCH 2/4] blk-cbt: Factor out common capability check

[Nikolay Borisov]

Instead of duplicating CAP_SYS_ADMIN check for every block-cbt ioctl
apart from BLKCBTGET simply factor out the check in the beginning of
blk_cbt_ioctl.

Signed-off-by: Nikolay Borisov <nikolay.borisov at virtuozzo.com>
---
 block/blk-cbt.c | 17 +++--------------
 1 file changed, 3 insertions(+), 14 deletions(-)

diff --git a/block/blk-cbt.c b/block/blk-cbt.c
index e2a9be83ac0d..269709c7589b 100644
--- a/block/blk-cbt.c
+++ b/block/blk-cbt.c
@@ -992,32 +992,21 @@ int blk_cbt_ioctl(struct block_device *bdev, unsigned cmd, char __user *arg)
 {
 	struct blk_user_cbt_info __user *ucbt_ioc = (struct blk_user_cbt_info __user *) arg;
 
+	if (cmd != BLKCBTGET && !capable(CAP_SYS_ADMIN))
+		return -EACCES;
+
 	switch(cmd) {
 	case BLKCBTSTART:
-		if (!capable(CAP_SYS_ADMIN))
-			return -EACCES;
 		return cbt_ioc_init(bdev, ucbt_ioc);
 	case BLKCBTSTOP:
-		if (!capable(CAP_SYS_ADMIN))
-			return -EACCES;
-
 		return cbt_ioc_stop(bdev);
 	case BLKCBTGET:
 		return cbt_ioc_get(bdev, ucbt_ioc);
 	case BLKCBTSET:
-		if (!capable(CAP_SYS_ADMIN))
-			return -EACCES;
-
 		return cbt_ioc_set(bdev, ucbt_ioc, 1);
 	case BLKCBTCLR:
-		if (!capable(CAP_SYS_ADMIN))
-			return -EACCES;
-
 		return cbt_ioc_set(bdev, ucbt_ioc, 0);
 	case BLKCBTMISC:
-		if (!capable(CAP_SYS_ADMIN))
-			return -EACCES;
-
 		return cbt_ioc_misc(bdev, arg);
 	default:
 		BUG();
-- 
2.34.1