[ALSA] Memory leak in sound/pcmcia/pdaudiocf/pdaudiocf.c
[linux-2.6.git] / ipc / sem.c
index 70975ce..6013c75 100644 (file)
--- a/ipc/sem.c
+++ b/ipc/sem.c
  * /proc/sysvipc/sem support (c) 1999 Dragos Acostachioaie <dragos@iname.com>
  *
  * SMP-threaded, sysctl's added
- * (c) 1999 Manfred Spraul <manfreds@colorfullife.com>
+ * (c) 1999 Manfred Spraul <manfred@colorfullife.com>
  * Enforced range limit on SEM_UNDO
  * (c) 2001 Red Hat Inc <alan@redhat.com>
  * Lockless wakeup
  * (c) 2003 Manfred Spraul <manfred@colorfullife.com>
+ *
+ * support for audit of ipc object properties and permission changes
+ * Dustin Kirkland <dustin.kirkland@us.ibm.com>
  */
 
-#include <linux/config.h>
 #include <linux/slab.h>
 #include <linux/spinlock.h>
 #include <linux/init.h>
 #include <linux/security.h>
 #include <linux/syscalls.h>
 #include <linux/audit.h>
+#include <linux/capability.h>
+#include <linux/seq_file.h>
+#include <linux/mutex.h>
+
 #include <asm/uaccess.h>
 #include "util.h"
 
@@ -89,7 +95,7 @@ static struct ipc_ids sem_ids;
 static int newary (key_t, int, int);
 static void freeary (struct sem_array *sma, int id);
 #ifdef CONFIG_PROC_FS
-static int sysvipc_sem_read_proc(char *buffer, char **start, off_t offset, int length, int *eof, void *data);
+static int sysvipc_sem_proc_show(struct seq_file *s, void *it);
 #endif
 
 #define SEMMSL_FAST    256 /* 512 bytes on stack */
@@ -116,10 +122,10 @@ void __init sem_init (void)
 {
        used_sems = 0;
        ipc_init_ids(&sem_ids,sc_semmni);
-
-#ifdef CONFIG_PROC_FS
-       create_proc_read_entry("sysvipc/sem", 0, NULL, sysvipc_sem_read_proc, NULL);
-#endif
+       ipc_init_proc_interface("sysvipc/sem",
+                               "       key      semid perms      nsems   uid   gid  cuid  cgid      otime      ctime\n",
+                               &sem_ids,
+                               sysvipc_sem_proc_show);
 }
 
 /*
@@ -137,7 +143,7 @@ void __init sem_init (void)
  *     * if it's IN_WAKEUP, then it must wait until the value changes
  *     * if it's not -EINTR, then the operation was completed by
  *       update_queue. semtimedop can return queue.status without
- *       performing any operation on the semaphore array.
+ *       performing any operation on the sem array.
  *     * otherwise it must acquire the spinlock and check what's up.
  *
  * The two-stage algorithm is necessary to protect against the following
@@ -193,6 +199,7 @@ static int newary (key_t key, int nsems, int semflg)
        }
        used_sems += nsems;
 
+       sma->sem_id = sem_buildid(id, sma->sem_perm.seq);
        sma->sem_base = (struct sem *) &sma[1];
        /* sma->sem_pending = NULL; */
        sma->sem_pending_last = &sma->sem_pending;
@@ -201,7 +208,7 @@ static int newary (key_t key, int nsems, int semflg)
        sma->sem_ctime = get_seconds();
        sem_unlock(sma);
 
-       return sem_buildid(id, sma->sem_perm.seq);
+       return sma->sem_id;
 }
 
 asmlinkage long sys_semget (key_t key, int nsems, int semflg)
@@ -211,7 +218,7 @@ asmlinkage long sys_semget (key_t key, int nsems, int semflg)
 
        if (nsems < 0 || nsems > sc_semmsl)
                return -EINVAL;
-       down(&sem_ids.sem);
+       mutex_lock(&sem_ids.mutex);
        
        if (key == IPC_PRIVATE) {
                err = newary(key, nsems, semflg);
@@ -224,8 +231,7 @@ asmlinkage long sys_semget (key_t key, int nsems, int semflg)
                err = -EEXIST;
        } else {
                sma = sem_lock(id);
-               if(sma==NULL)
-                       BUG();
+               BUG_ON(sma==NULL);
                if (nsems > sma->sem_nsems)
                        err = -EINVAL;
                else if (ipcperms(&sma->sem_perm, semflg))
@@ -239,7 +245,7 @@ asmlinkage long sys_semget (key_t key, int nsems, int semflg)
                sem_unlock(sma);
        }
 
-       up(&sem_ids.sem);
+       mutex_unlock(&sem_ids.mutex);
        return err;
 }
 
@@ -379,6 +385,7 @@ static void update_queue (struct sem_array * sma)
                        /* hands-off: q will disappear immediately after
                         * writing q->status.
                         */
+                       smp_wmb();
                        q->status = error;
                        q = n;
                } else {
@@ -433,8 +440,8 @@ static int count_semzcnt (struct sem_array * sma, ushort semnum)
        return semzcnt;
 }
 
-/* Free a semaphore set. freeary() is called with sem_ids.sem down and
- * the spinlock for this semaphore set hold. sem_ids.sem remains locked
+/* Free a semaphore set. freeary() is called with sem_ids.mutex locked and
+ * the spinlock for this semaphore set hold. sem_ids.mutex remains locked
  * on exit.
  */
 static void freeary (struct sem_array *sma, int id)
@@ -459,6 +466,7 @@ static void freeary (struct sem_array *sma, int id)
                n = q->next;
                q->status = IN_WAKEUP;
                wake_up_process(q->sleeper); /* doesn't sleep */
+               smp_wmb();
                q->status = -EIDRM;     /* hands-off q */
                q = n;
        }
@@ -520,7 +528,7 @@ static int semctl_nolock(int semid, int semnum, int cmd, int version, union semu
                seminfo.semmnu = SEMMNU;
                seminfo.semmap = SEMMAP;
                seminfo.semume = SEMUME;
-               down(&sem_ids.sem);
+               mutex_lock(&sem_ids.mutex);
                if (cmd == SEM_INFO) {
                        seminfo.semusz = sem_ids.in_use;
                        seminfo.semaem = used_sems;
@@ -529,7 +537,7 @@ static int semctl_nolock(int semid, int semnum, int cmd, int version, union semu
                        seminfo.semaem = SEMAEM;
                }
                max_id = sem_ids.max_id;
-               up(&sem_ids.sem);
+               mutex_unlock(&sem_ids.mutex);
                if (copy_to_user (arg.__buf, &seminfo, sizeof(struct seminfo))) 
                        return -EFAULT;
                return (max_id < 0) ? 0: max_id;
@@ -804,8 +812,6 @@ static int semctl_down(int semid, int semnum, int cmd, int version, union semun
        if(cmd == IPC_SET) {
                if(copy_semid_from_user (&setbuf, arg.buf, version))
                        return -EFAULT;
-               if ((err = audit_ipc_perms(0, setbuf.uid, setbuf.gid, setbuf.mode)))
-                       return err;
        }
        sma = sem_lock(semid);
        if(sma==NULL)
@@ -816,7 +822,16 @@ static int semctl_down(int semid, int semnum, int cmd, int version, union semun
                goto out_unlock;
        }       
        ipcp = &sma->sem_perm;
-       
+
+       err = audit_ipc_obj(ipcp);
+       if (err)
+               goto out_unlock;
+
+       if (cmd == IPC_SET) {
+               err = audit_ipc_set_perm(0, setbuf.uid, setbuf.gid, setbuf.mode);
+               if (err)
+                       goto out_unlock;
+       }
        if (current->euid != ipcp->cuid && 
            current->euid != ipcp->uid && !capable(CAP_SYS_ADMIN)) {
                err=-EPERM;
@@ -881,9 +896,9 @@ asmlinkage long sys_semctl (int semid, int semnum, int cmd, union semun arg)
                return err;
        case IPC_RMID:
        case IPC_SET:
-               down(&sem_ids.sem);
+               mutex_lock(&sem_ids.mutex);
                err = semctl_down(semid,semnum,cmd,version,arg);
-               up(&sem_ids.sem);
+               mutex_unlock(&sem_ids.mutex);
                return err;
        default:
                return -EINVAL;
@@ -1177,8 +1192,7 @@ retry_undos:
 
        sma = sem_lock(semid);
        if(sma==NULL) {
-               if(queue.prev != NULL)
-                       BUG();
+               BUG_ON(queue.prev != NULL);
                error = -EIDRM;
                goto out_free;
        }
@@ -1295,9 +1309,9 @@ found:
                /* perform adjustments registered in u */
                nsems = sma->sem_nsems;
                for (i = 0; i < nsems; i++) {
-                       struct sem * sem = &sma->sem_base[i];
+                       struct sem * semaphore = &sma->sem_base[i];
                        if (u->semadj[i]) {
-                               sem->semval += u->semadj[i];
+                               semaphore->semval += u->semadj[i];
                                /*
                                 * Range checks of the new semaphore value,
                                 * not defined by sus:
@@ -1311,11 +1325,11 @@ found:
                                 *
                                 *      Manfred <manfred@colorfullife.com>
                                 */
-                               if (sem->semval < 0)
-                                       sem->semval = 0;
-                               if (sem->semval > SEMVMX)
-                                       sem->semval = SEMVMX;
-                               sem->sempid = current->tgid;
+                               if (semaphore->semval < 0)
+                                       semaphore->semval = 0;
+                               if (semaphore->semval > SEMVMX)
+                                       semaphore->semval = SEMVMX;
+                               semaphore->sempid = current->tgid;
                        }
                }
                sma->sem_otime = get_seconds();
@@ -1328,50 +1342,21 @@ next_entry:
 }
 
 #ifdef CONFIG_PROC_FS
-static int sysvipc_sem_read_proc(char *buffer, char **start, off_t offset, int length, int *eof, void *data)
+static int sysvipc_sem_proc_show(struct seq_file *s, void *it)
 {
-       off_t pos = 0;
-       off_t begin = 0;
-       int i, len = 0;
-
-       len += sprintf(buffer, "       key      semid perms      nsems   uid   gid  cuid  cgid      otime      ctime\n");
-       down(&sem_ids.sem);
-
-       for(i = 0; i <= sem_ids.max_id; i++) {
-               struct sem_array *sma;
-               sma = sem_lock(i);
-               if(sma) {
-                       len += sprintf(buffer + len, "%10d %10d  %4o %10lu %5u %5u %5u %5u %10lu %10lu\n",
-                               sma->sem_perm.key,
-                               sem_buildid(i,sma->sem_perm.seq),
-                               sma->sem_perm.mode,
-                               sma->sem_nsems,
-                               sma->sem_perm.uid,
-                               sma->sem_perm.gid,
-                               sma->sem_perm.cuid,
-                               sma->sem_perm.cgid,
-                               sma->sem_otime,
-                               sma->sem_ctime);
-                       sem_unlock(sma);
-
-                       pos += len;
-                       if(pos < offset) {
-                               len = 0;
-                               begin = pos;
-                       }
-                       if(pos > offset + length)
-                               goto done;
-               }
-       }
-       *eof = 1;
-done:
-       up(&sem_ids.sem);
-       *start = buffer + (offset - begin);
-       len -= (offset - begin);
-       if(len > length)
-               len = length;
-       if(len < 0)
-               len = 0;
-       return len;
+       struct sem_array *sma = it;
+
+       return seq_printf(s,
+                         "%10d %10d  %4o %10lu %5u %5u %5u %5u %10lu %10lu\n",
+                         sma->sem_perm.key,
+                         sma->sem_id,
+                         sma->sem_perm.mode,
+                         sma->sem_nsems,
+                         sma->sem_perm.uid,
+                         sma->sem_perm.gid,
+                         sma->sem_perm.cuid,
+                         sma->sem_perm.cgid,
+                         sma->sem_otime,
+                         sma->sem_ctime);
 }
 #endif