2022-05-02 23:12:15

by Christian Göttsche

[permalink] [raw]
Subject: [PATCH v2 3/8] block: use new capable_or functionality

Use the new added capable_or function in appropriate cases, where a task
is required to have any of two capabilities.

Reorder CAP_SYS_ADMIN last.

Fixes: 94c4b4fd25e6 ("block: Check ADMIN before NICE for IOPRIO_CLASS_RT")

Signed-off-by: Christian Göttsche <[email protected]>
---
block/ioprio.c | 9 +--------
1 file changed, 1 insertion(+), 8 deletions(-)

diff --git a/block/ioprio.c b/block/ioprio.c
index 2fe068fcaad5..52d5da286323 100644
--- a/block/ioprio.c
+++ b/block/ioprio.c
@@ -37,14 +37,7 @@ int ioprio_check_cap(int ioprio)

switch (class) {
case IOPRIO_CLASS_RT:
- /*
- * Originally this only checked for CAP_SYS_ADMIN,
- * which was implicitly allowed for pid 0 by security
- * modules such as SELinux. Make sure we check
- * CAP_SYS_ADMIN first to avoid a denial/avc for
- * possibly missing CAP_SYS_NICE permission.
- */
- if (!capable(CAP_SYS_ADMIN) && !capable(CAP_SYS_NICE))
+ if (!capable_or(CAP_SYS_NICE, CAP_SYS_ADMIN))
return -EPERM;
fallthrough;
/* rt has prio field too */
--
2.36.0