These helpers will make it less error prone to use override_creds_light()/revert_creds_light(). They make sure that they are paired. As they use the _light() version of the credentials override/revert operations, they should only be used when there are guarantees that the lifetime of the credentials in question is not modified during the critical section. Suggested-by: Christian Brauner <brauner@xxxxxxxxxx> Signed-off-by: Vinicius Costa Gomes <vinicius.gomes@xxxxxxxxx> --- include/linux/cred.h | 7 +++++++ 1 file changed, 7 insertions(+) diff --git a/include/linux/cred.h b/include/linux/cred.h index e4a3155fe409..f4f3d55cd6a2 100644 --- a/include/linux/cred.h +++ b/include/linux/cred.h @@ -190,6 +190,13 @@ static inline void revert_creds_light(const struct cred *revert_cred) rcu_assign_pointer(current->cred, revert_cred); } +DEFINE_LOCK_GUARD_1(__cred, struct cred, + _T->lock = (struct cred *)override_creds_light(_T->lock), + revert_creds_light(_T->lock)); + +#define cred_guard(_cred) guard(__cred)(((struct cred *)_cred)) +#define cred_scoped_guard(_cred) scoped_guard(__cred, ((struct cred *)_cred)) + /** * get_new_cred_many - Get references on a new set of credentials * @cred: The new credentials to reference -- 2.46.0
