ipc: integrate ipc_checkid() into ipc_lock()
This patch introduces a new ipc_lock_check() routine interface:
. each time ipc_checkid() is called, this is done after calling ipc_lock().
ipc_checkid() is now called from inside ipc_lock_check().
[akpm@linux-foundation.org: build fix]
[akpm@linux-foundation.org: fix RCU locking]
Signed-off-by: Nadia Derbey <Nadia.Derbey@bull.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
diff --git a/ipc/sem.c b/ipc/sem.c
index 6af226a..673d63d 100644
--- a/ipc/sem.c
+++ b/ipc/sem.c
@@ -88,7 +88,6 @@
#define sem_ids(ns) (*((ns)->ids[IPC_SEM_IDS]))
-#define sem_lock(ns, id) ((struct sem_array*)ipc_lock(&sem_ids(ns), id))
#define sem_unlock(sma) ipc_unlock(&(sma)->sem_perm)
#define sem_checkid(ns, sma, semid) \
ipc_checkid(&sem_ids(ns),&sma->sem_perm,semid)
@@ -175,6 +174,17 @@
IPC_SEM_IDS, sysvipc_sem_proc_show);
}
+static inline struct sem_array *sem_lock(struct ipc_namespace *ns, int id)
+{
+ return (struct sem_array *) ipc_lock(&sem_ids(ns), id);
+}
+
+static inline struct sem_array *sem_lock_check(struct ipc_namespace *ns,
+ int id)
+{
+ return (struct sem_array *) ipc_lock_check(&sem_ids(ns), id);
+}
+
static inline void sem_rmid(struct ipc_namespace *ns, struct sem_array *s)
{
ipc_rmid(&sem_ids(ns), &s->sem_perm);
@@ -599,11 +609,9 @@
struct semid64_ds tbuf;
int id;
- memset(&tbuf,0,sizeof(tbuf));
-
sma = sem_lock(ns, semid);
- if(sma == NULL)
- return -EINVAL;
+ if (IS_ERR(sma))
+ return PTR_ERR(sma);
err = -EACCES;
if (ipcperms (&sma->sem_perm, S_IRUGO))
@@ -615,6 +623,8 @@
id = sma->sem_perm.id;
+ memset(&tbuf, 0, sizeof(tbuf));
+
kernel_to_ipc64_perm(&sma->sem_perm, &tbuf.sem_perm);
tbuf.sem_otime = sma->sem_otime;
tbuf.sem_ctime = sma->sem_ctime;
@@ -643,16 +653,12 @@
ushort* sem_io = fast_sem_io;
int nsems;
- sma = sem_lock(ns, semid);
- if(sma==NULL)
- return -EINVAL;
+ sma = sem_lock_check(ns, semid);
+ if (IS_ERR(sma))
+ return PTR_ERR(sma);
nsems = sma->sem_nsems;
- err=-EIDRM;
- if (sem_checkid(ns,sma,semid))
- goto out_unlock;
-
err = -EACCES;
if (ipcperms (&sma->sem_perm, (cmd==SETVAL||cmd==SETALL)?S_IWUGO:S_IRUGO))
goto out_unlock;
@@ -864,14 +870,10 @@
if(copy_semid_from_user (&setbuf, arg.buf, version))
return -EFAULT;
}
- sma = sem_lock(ns, semid);
- if(sma==NULL)
- return -EINVAL;
+ sma = sem_lock_check(ns, semid);
+ if (IS_ERR(sma))
+ return PTR_ERR(sma);
- if (sem_checkid(ns,sma,semid)) {
- err=-EIDRM;
- goto out_unlock;
- }
ipcp = &sma->sem_perm;
err = audit_ipc_obj(ipcp);
@@ -1055,15 +1057,10 @@
goto out;
/* no undo structure around - allocate one. */
- sma = sem_lock(ns, semid);
- un = ERR_PTR(-EINVAL);
- if(sma==NULL)
- goto out;
- un = ERR_PTR(-EIDRM);
- if (sem_checkid(ns,sma,semid)) {
- sem_unlock(sma);
- goto out;
- }
+ sma = sem_lock_check(ns, semid);
+ if (IS_ERR(sma))
+ return ERR_PTR(PTR_ERR(sma));
+
nsems = sma->sem_nsems;
ipc_rcu_getref(sma);
sem_unlock(sma);
@@ -1169,15 +1166,14 @@
} else
un = NULL;
- sma = sem_lock(ns, semid);
- error=-EINVAL;
- if(sma==NULL)
+ sma = sem_lock_check(ns, semid);
+ if (IS_ERR(sma)) {
+ error = PTR_ERR(sma);
goto out_free;
- error = -EIDRM;
- if (sem_checkid(ns,sma,semid))
- goto out_unlock_free;
+ }
+
/*
- * semid identifies are not unique - find_undo may have
+ * semid identifiers are not unique - find_undo may have
* allocated an undo structure, it was invalidated by an RMID
* and now a new array with received the same id. Check and retry.
*/
@@ -1243,7 +1239,7 @@
}
sma = sem_lock(ns, semid);
- if(sma==NULL) {
+ if (IS_ERR(sma)) {
BUG_ON(queue.prev != NULL);
error = -EIDRM;
goto out_free;
@@ -1343,7 +1339,7 @@
if(semid == -1)
continue;
sma = sem_lock(ns, semid);
- if (sma == NULL)
+ if (IS_ERR(sma))
continue;
if (u->semid == -1)