ipc/util.c: further variable name cleanups

The varable names got a mess, thus standardize them again:

id: user space id. Called semid, shmid, msgid if the type is known.
    Most functions use "id" already.
idx: "index" for the idr lookup
    Right now, some functions use lid, ipc_addid() already uses idx as
    the variable name.
seq: sequence number, to avoid quick collisions of the user space id
key: user space key, used for the rhash tree

Link: http://lkml.kernel.org/r/20180712185241.4017-12-manfred@colorfullife.com
Signed-off-by: Manfred Spraul <manfred@colorfullife.com>
Cc: Dmitry Vyukov <dvyukov@google.com>
Cc: Davidlohr Bueso <dave@stgolabs.net>
Cc: Davidlohr Bueso <dbueso@suse.de>
Cc: Herbert Xu <herbert@gondor.apana.org.au>
Cc: Kees Cook <keescook@chromium.org>
Cc: Michael Kerrisk <mtk.manpages@gmail.com>
Cc: Michal Hocko <mhocko@suse.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

6 files changed, 27 insertions, 27 deletions

diff --git a/include/linux/ipc_namespace.h b/include/linux/ipc_namespace.h
index e9ccdfdb1928..6ab8c1bada3f 100644
--- a/include/linux/ipc_namespace.h
+++ b/include/linux/ipc_namespace.h
@@ -18,7 +18,7 @@ struct ipc_ids {
         unsigned short seq;
         struct rw_semaphore rwsem;
         struct idr ipcs_idr;
-        int max_id;
+        int max_idx;
 #ifdef CONFIG_CHECKPOINT_RESTORE
         int next_id;
 #endif
diff --git a/ipc/msg.c b/ipc/msg.c
index ee78dad90460..883642cf2b27 100644
--- a/ipc/msg.c
+++ b/ipc/msg.c
@@ -456,7 +456,7 @@ static int msgctl_info(struct ipc_namespace *ns, int msqid,
                          int cmd, struct msginfo *msginfo)
 {
         int err;
-        int max_id;
+        int max_idx;
 
         /*
          * We must not return kernel stack data.
@@ -483,9 +483,9 @@ static int msgctl_info(struct ipc_namespace *ns, int msqid,
                 msginfo->msgpool = MSGPOOL;
                 msginfo->msgtql = MSGTQL;
         }
-        max_id = ipc_get_maxid(&msg_ids(ns));
+        max_idx = ipc_get_maxidx(&msg_ids(ns));
         up_read(&msg_ids(ns).rwsem);
-        return (max_id < 0) ? 0 : max_id;
+        return (max_idx < 0) ? 0 : max_idx;
 }
 
 static int msgctl_stat(struct ipc_namespace *ns, int msqid,
diff --git a/ipc/sem.c b/ipc/sem.c
index e4df102f3404..26f8e37fcdcb 100644
--- a/ipc/sem.c
+++ b/ipc/sem.c
@@ -1294,7 +1294,7 @@ static int semctl_info(struct ipc_namespace *ns, int semid,
                          int cmd, void __user *p)
 {
         struct seminfo seminfo;
-        int max_id;
+        int max_idx;
         int err;
 
         err = security_sem_semctl(NULL, cmd);
@@ -1318,11 +1318,11 @@ static int semctl_info(struct ipc_namespace *ns, int semid,
                 seminfo.semusz = SEMUSZ;
                 seminfo.semaem = SEMAEM;
         }
-        max_id = ipc_get_maxid(&sem_ids(ns));
+        max_idx = ipc_get_maxidx(&sem_ids(ns));
         up_read(&sem_ids(ns).rwsem);
         if (copy_to_user(p, &seminfo, sizeof(struct seminfo)))
                 return -EFAULT;
-        return (max_id < 0) ? 0 : max_id;
+        return (max_idx < 0) ? 0 : max_idx;
 }
 
 static int semctl_setval(struct ipc_namespace *ns, int semid, int semnum,
diff --git a/ipc/shm.c b/ipc/shm.c
index c4fb359f1e53..b0eb3757ab89 100644
--- a/ipc/shm.c
+++ b/ipc/shm.c
@@ -948,7 +948,7 @@ static int shmctl_ipc_info(struct ipc_namespace *ns,
                 shminfo->shmall = ns->shm_ctlall;
                 shminfo->shmmin = SHMMIN;
                 down_read(&shm_ids(ns).rwsem);
-                err = ipc_get_maxid(&shm_ids(ns));
+                err = ipc_get_maxidx(&shm_ids(ns));
                 up_read(&shm_ids(ns).rwsem);
                 if (err < 0)
                         err = 0;
@@ -968,7 +968,7 @@ static int shmctl_shm_info(struct ipc_namespace *ns,
                 shm_info->shm_tot = ns->shm_tot;
                 shm_info->swap_attempts = 0;
                 shm_info->swap_successes = 0;
-                err = ipc_get_maxid(&shm_ids(ns));
+                err = ipc_get_maxidx(&shm_ids(ns));
                 up_read(&shm_ids(ns).rwsem);
                 if (err < 0)
                         err = 0;
diff --git a/ipc/util.c b/ipc/util.c
index a2aae8c1410d..6f30ba80ca15 100644
--- a/ipc/util.c
+++ b/ipc/util.c
@@ -119,7 +119,7 @@ void ipc_init_ids(struct ipc_ids *ids)
         init_rwsem(&ids->rwsem);
         rhashtable_init(&ids->key_ht, &ipc_kht_params);
         idr_init(&ids->ipcs_idr);
-        ids->max_id = -1;
+        ids->max_idx = -1;
 #ifdef CONFIG_CHECKPOINT_RESTORE
         ids->next_id = -1;
 #endif
@@ -237,7 +237,7 @@ static inline int ipc_idr_alloc(struct ipc_ids *ids, struct kern_ipc_perm *new)
  * @limit: limit for the number of used ids
  *
  * Add an entry 'new' to the ipc ids idr. The permissions object is
- * initialised and the first free entry is set up and the id assigned
+ * initialised and the first free entry is set up and the index assigned
  * is returned. The 'new' entry is returned in a locked state on success.
  *
  * On failure the entry is not locked and a negative err-code is returned.
@@ -291,8 +291,8 @@ int ipc_addid(struct ipc_ids *ids, struct kern_ipc_perm *new, int limit)
         }
 
         ids->in_use++;
-        if (idx > ids->max_id)
-                ids->max_id = idx;
+        if (idx > ids->max_idx)
+                ids->max_idx = idx;
         return idx;
 }
 
@@ -431,20 +431,20 @@ static void ipc_kht_remove(struct ipc_ids *ids, struct kern_ipc_perm *ipcp)
  */
 void ipc_rmid(struct ipc_ids *ids, struct kern_ipc_perm *ipcp)
 {
-        int lid = ipcid_to_idx(ipcp->id);
+        int idx = ipcid_to_idx(ipcp->id);
 
-        idr_remove(&ids->ipcs_idr, lid);
+        idr_remove(&ids->ipcs_idr, idx);
         ipc_kht_remove(ids, ipcp);
         ids->in_use--;
         ipcp->deleted = true;
 
-        if (unlikely(lid == ids->max_id)) {
+        if (unlikely(idx == ids->max_idx)) {
                 do {
-                        lid--;
-                        if (lid == -1)
+                        idx--;
+                        if (idx == -1)
                                 break;
-                } while (!idr_find(&ids->ipcs_idr, lid));
-                ids->max_id = lid;
+                } while (!idr_find(&ids->ipcs_idr, idx));
+                ids->max_idx = idx;
         }
 }
 
@@ -564,9 +564,9 @@ void ipc64_perm_to_ipc_perm(struct ipc64_perm *in, struct ipc_perm *out)
 struct kern_ipc_perm *ipc_obtain_object_idr(struct ipc_ids *ids, int id)
 {
         struct kern_ipc_perm *out;
-        int lid = ipcid_to_idx(id);
+        int idx = ipcid_to_idx(id);
 
-        out = idr_find(&ids->ipcs_idr, lid);
+        out = idr_find(&ids->ipcs_idr, idx);
         if (!out)
                 return ERR_PTR(-EINVAL);
 
diff --git a/ipc/util.h b/ipc/util.h
index 6c5c77c61f85..e74564fe3375 100644
--- a/ipc/util.h
+++ b/ipc/util.h
@@ -113,12 +113,12 @@ void ipc_set_key_private(struct ipc_ids *, struct kern_ipc_perm *);
 int ipcperms(struct ipc_namespace *ns, struct kern_ipc_perm *ipcp, short flg);
 
 /**
- * ipc_get_maxid - get the last assigned id
+ * ipc_get_maxidx - get the highest assigned index
  * @ids: ipc identifier set
  *
  * Called with ipc_ids.rwsem held for reading.
  */
-static inline int ipc_get_maxid(struct ipc_ids *ids)
+static inline int ipc_get_maxidx(struct ipc_ids *ids)
 {
         if (ids->in_use == 0)
                 return -1;
@@ -126,7 +126,7 @@ static inline int ipc_get_maxid(struct ipc_ids *ids)
         if (ids->in_use == IPCMNI)
                 return IPCMNI - 1;
 
-        return ids->max_id;
+        return ids->max_idx;
 }
 
 /*
@@ -172,9 +172,9 @@ extern struct msg_msg *load_msg(const void __user *src, size_t len);
 extern struct msg_msg *copy_msg(struct msg_msg *src, struct msg_msg *dst);
 extern int store_msg(void __user *dest, struct msg_msg *msg, size_t len);
 
-static inline int ipc_checkid(struct kern_ipc_perm *ipcp, int uid)
+static inline int ipc_checkid(struct kern_ipc_perm *ipcp, int id)
 {
-        return uid / SEQ_MULTIPLIER != ipcp->seq;
+        return ipcid_to_seqx(id) != ipcp->seq;
 }
 
 static inline void ipc_lock_object(struct kern_ipc_perm *perm)