diff options
| author | Stephen Smalley <stephen.smalley.work@gmail.com> | 2020-08-19 15:45:16 -0400 |
|---|---|---|
| committer | Paul Moore <paul@paul-moore.com> | 2020-08-25 08:34:47 -0400 |
| commit | 1b8b31a2e6120b7b2bc99137c0ba1ae3e45dbd7d (patch) | |
| tree | 7c263dfa7217f93b7b12ac5d1417d598ba874e36 /security/selinux/include | |
| parent | c76a2f9ecdcb44cdcdb2de82e90d84283736aeb2 (diff) | |
selinux: convert policy read-write lock to RCU
Convert the policy read-write lock to RCU. This is significantly
simplified by the earlier work to encapsulate the policy data
structures and refactor the policy load and boolean setting logic.
Move the latest_granting sequence number into the selinux_policy
structure so that it can be updated atomically with the policy.
Since removing the policy rwlock and moving latest_granting reduces
the selinux_ss structure to nothing more than a wrapper around the
selinux_policy pointer, get rid of the extra layer of indirection.
At present this change merely passes a hardcoded 1 to
rcu_dereference_check() in the cases where we know we do not need to
take rcu_read_lock(), with the preceding comment explaining why.
Alternatively we could pass fsi->mutex down from selinuxfs and
apply a lockdep check on it instead.
Based in part on earlier attempts to convert the policy rwlock
to RCU by Kaigai Kohei [1] and by Peter Enderborg [2].
[1] https://lore.kernel.org/selinux/6e2f9128-e191-ebb3-0e87-74bfccb0767f@tycho.nsa.gov/
[2] https://lore.kernel.org/selinux/20180530141104.28569-1-peter.enderborg@sony.com/
Signed-off-by: Stephen Smalley <stephen.smalley.work@gmail.com>
Reviewed-by: Ondrej Mosnacek <omosnace@redhat.com>
Signed-off-by: Paul Moore <paul@paul-moore.com>
Diffstat (limited to 'security/selinux/include')
| -rw-r--r-- | security/selinux/include/security.h | 5 |
1 files changed, 2 insertions, 3 deletions
diff --git a/security/selinux/include/security.h b/security/selinux/include/security.h index c68ed2beadff..505e51264d51 100644 --- a/security/selinux/include/security.h +++ b/security/selinux/include/security.h @@ -13,6 +13,7 @@ #include <linux/dcache.h> #include <linux/magic.h> #include <linux/types.h> +#include <linux/rcupdate.h> #include <linux/refcount.h> #include <linux/workqueue.h> #include "flask.h" @@ -84,7 +85,6 @@ extern int selinux_enabled_boot; #define POLICYDB_BOUNDS_MAXDEPTH 4 struct selinux_avc; -struct selinux_ss; struct selinux_policy; struct selinux_state { @@ -102,10 +102,9 @@ struct selinux_state { struct mutex status_lock; struct selinux_avc *avc; - struct selinux_ss *ss; + struct selinux_policy __rcu *policy; } __randomize_layout; -void selinux_ss_init(struct selinux_ss **ss); void selinux_avc_init(struct selinux_avc **avc); extern struct selinux_state selinux_state; |