shm/security: Pass kern_ipc_perm not shmid_kernel into the shm security hooks

All of the implementations of security hooks that take shmid_kernel only
access shm_perm the struct kern_ipc_perm member.  This means the
dependencies of the shm security hooks can be simplified by passing
the kern_ipc_perm member of shmid_kernel..

Making this change will allow struct shmid_kernel to become private to ipc/shm.c.

Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>

1 files changed, 7 insertions, 10 deletions

diff --git a/ipc/shm.c b/ipc/shm.c
index 4643865e9171..387a786e7be1 100644
--- a/ipc/shm.c
+++ b/ipc/shm.c
@@ -181,7 +181,7 @@ static void shm_rcu_free(struct rcu_head *head)
                                                         rcu);
         struct shmid_kernel *shp = container_of(ptr, struct shmid_kernel,
                                                         shm_perm);
-        security_shm_free(shp);
+        security_shm_free(&shp->shm_perm);
         kvfree(shp);
 }
 
@@ -554,7 +554,7 @@ static int newseg(struct ipc_namespace *ns, struct ipc_params *params)
         shp->mlock_user = NULL;
 
         shp->shm_perm.security = NULL;
-        error = security_shm_alloc(shp);
+        error = security_shm_alloc(&shp->shm_perm);
         if (error) {
                 kvfree(shp);
                 return error;
@@ -635,10 +635,7 @@ no_file:
  */
 static inline int shm_security(struct kern_ipc_perm *ipcp, int shmflg)
 {
-        struct shmid_kernel *shp;
-
-        shp = container_of(ipcp, struct shmid_kernel, shm_perm);
-        return security_shm_associate(shp, shmflg);
+        return security_shm_associate(ipcp, shmflg);
 }
 
 /*
@@ -835,7 +832,7 @@ static int shmctl_down(struct ipc_namespace *ns, int shmid, int cmd,
 
         shp = container_of(ipcp, struct shmid_kernel, shm_perm);
 
-        err = security_shm_shmctl(shp, cmd);
+        err = security_shm_shmctl(&shp->shm_perm, cmd);
         if (err)
                 goto out_unlock1;
 
@@ -934,7 +931,7 @@ static int shmctl_stat(struct ipc_namespace *ns, int shmid,
         if (ipcperms(ns, &shp->shm_perm, S_IRUGO))
                 goto out_unlock;
 
-        err = security_shm_shmctl(shp, cmd);
+        err = security_shm_shmctl(&shp->shm_perm, cmd);
         if (err)
                 goto out_unlock;
 
@@ -978,7 +975,7 @@ static int shmctl_do_lock(struct ipc_namespace *ns, int shmid, int cmd)
         }
 
         audit_ipc_obj(&(shp->shm_perm));
-        err = security_shm_shmctl(shp, cmd);
+        err = security_shm_shmctl(&shp->shm_perm, cmd);
         if (err)
                 goto out_unlock1;
 
@@ -1348,7 +1345,7 @@ long do_shmat(int shmid, char __user *shmaddr, int shmflg,
         if (ipcperms(ns, &shp->shm_perm, acc_mode))
                 goto out_unlock;
 
-        err = security_shm_shmat(shp, shmaddr, shmflg);
+        err = security_shm_shmat(&shp->shm_perm, shmaddr, shmflg);
         if (err)
                 goto out_unlock;