fix rcu annotations noise in cred.h

task->cred is declared as __rcu, and access to other tasks' ->cred is,
indeed, protected.  Access to current->cred does not need rcu_dereference()
at all, since only the task itself can change its ->cred.  sparse, of
course, has no way of knowing that...

Add force-cast in current_cred(), make current_fsuid() et.al. use it.

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This commit is contained in:
Al Viro 2011-08-07 18:55:11 +01:00 committed by Linus Torvalds
parent 7813b94a54
commit 3295514841

View file

@ -265,10 +265,11 @@ static inline void put_cred(const struct cred *_cred)
/**
* current_cred - Access the current task's subjective credentials
*
* Access the subjective credentials of the current task.
* Access the subjective credentials of the current task. RCU-safe,
* since nobody else can modify it.
*/
#define current_cred() \
(current->cred)
(*(__force struct cred **)&current->cred)
/**
* __task_cred - Access a task's objective credentials
@ -307,7 +308,7 @@ static inline void put_cred(const struct cred *_cred)
({ \
struct user_struct *__u; \
struct cred *__cred; \
__cred = (struct cred *) current_cred(); \
__cred = current_cred(); \
__u = get_uid(__cred->user); \
__u; \
})
@ -322,7 +323,7 @@ static inline void put_cred(const struct cred *_cred)
({ \
struct group_info *__groups; \
struct cred *__cred; \
__cred = (struct cred *) current_cred(); \
__cred = current_cred(); \
__groups = get_group_info(__cred->group_info); \
__groups; \
})
@ -341,7 +342,7 @@ static inline void put_cred(const struct cred *_cred)
#define current_cred_xxx(xxx) \
({ \
current->cred->xxx; \
current_cred()->xxx; \
})
#define current_uid() (current_cred_xxx(uid))