ipc: clean up ipc/shm.c

Use the macro shm_ids().

Remove useless check for a userspace pointer, because copy_to_user()
will check it.

Some style cleanups.

Signed-off-by: WANG Cong <wangcong@zeuux.org>
Cc: Nadia Derbey <Nadia.Derbey@bull.net>
Cc: Pierre Peiffer <peifferp@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

1 files changed, 5 insertions, 10 deletions

diff --git a/ipc/shm.c b/ipc/shm.c
index 57dd50046cef..b125b560240e 100644
--- a/ipc/shm.c
+++ b/ipc/shm.c
@@ -75,7 +75,7 @@ void shm_init_ns(struct ipc_namespace *ns)
         ns->shm_ctlall = SHMALL;
         ns->shm_ctlmni = SHMMNI;
         ns->shm_tot = 0;
-        ipc_init_ids(&ns->ids[IPC_SHM_IDS]);
+        ipc_init_ids(&shm_ids(ns));
 }
 
 /*
@@ -644,7 +644,7 @@ asmlinkage long sys_shmctl(int shmid, int cmd, struct shmid_ds __user *buf)
                 if (err)
                         return err;
 
-                memset(&shminfo,0,sizeof(shminfo));
+                memset(&shminfo, 0, sizeof(shminfo));
                 shminfo.shmmni = shminfo.shmseg = ns->shm_ctlmni;
                 shminfo.shmmax = ns->shm_ctlmax;
                 shminfo.shmall = ns->shm_ctlall;
@@ -669,7 +669,7 @@ asmlinkage long sys_shmctl(int shmid, int cmd, struct shmid_ds __user *buf)
                 if (err)
                         return err;
 
-                memset(&shm_info,0,sizeof(shm_info));
+                memset(&shm_info, 0, sizeof(shm_info));
                 down_read(&shm_ids(ns).rw_mutex);
                 shm_info.used_ids = shm_ids(ns).in_use;
                 shm_get_stat (ns, &shm_info.shm_rss, &shm_info.shm_swp);
@@ -678,7 +678,7 @@ asmlinkage long sys_shmctl(int shmid, int cmd, struct shmid_ds __user *buf)
                 shm_info.swap_successes = 0;
                 err = ipc_get_maxid(&shm_ids(ns));
                 up_read(&shm_ids(ns).rw_mutex);
-                if(copy_to_user (buf, &shm_info, sizeof(shm_info))) {
+                if (copy_to_user(buf, &shm_info, sizeof(shm_info))) {
                         err = -EFAULT;
                         goto out;
                 }
@@ -692,11 +692,6 @@ asmlinkage long sys_shmctl(int shmid, int cmd, struct shmid_ds __user *buf)
                 struct shmid64_ds tbuf;
                 int result;
 
-                if (!buf) {
-                        err = -EFAULT;
-                        goto out;
-                }
-
                 if (cmd == SHM_STAT) {
                         shp = shm_lock(ns, shmid);
                         if (IS_ERR(shp)) {
@@ -712,7 +707,7 @@ asmlinkage long sys_shmctl(int shmid, int cmd, struct shmid_ds __user *buf)
                         }
                         result = 0;
                 }
-                err=-EACCES;
+                err = -EACCES;
                 if (ipcperms (&shp->shm_perm, S_IRUGO))
                         goto out_unlock;
                 err = security_shm_shmctl(shp, cmd);