#include <linux/seq_file.h>
#include <linux/rwsem.h>
#include <linux/nsproxy.h>
+#include <linux/ipc_namespace.h>
#include <asm/uaccess.h>
#include "util.h"
-#define sem_ids(ns) (*((ns)->ids[IPC_SEM_IDS]))
+#define sem_ids(ns) ((ns)->ids[IPC_SEM_IDS])
#define sem_unlock(sma) ipc_unlock(&(sma)->sem_perm)
#define sem_checkid(sma, semid) ipc_checkid(&sma->sem_perm, semid)
-#define sem_buildid(id, seq) ipc_buildid(id, seq)
-
-static struct ipc_ids init_sem_ids;
static int newary(struct ipc_namespace *, struct ipc_params *);
-static void freeary(struct ipc_namespace *, struct sem_array *);
+static void freeary(struct ipc_namespace *, struct kern_ipc_perm *);
#ifdef CONFIG_PROC_FS
static int sysvipc_sem_proc_show(struct seq_file *s, void *it);
#endif
#define sc_semopm sem_ctls[2]
#define sc_semmni sem_ctls[3]
-static void __sem_init_ns(struct ipc_namespace *ns, struct ipc_ids *ids)
+void sem_init_ns(struct ipc_namespace *ns)
{
- ns->ids[IPC_SEM_IDS] = ids;
ns->sc_semmsl = SEMMSL;
ns->sc_semmns = SEMMNS;
ns->sc_semopm = SEMOPM;
ns->sc_semmni = SEMMNI;
ns->used_sems = 0;
- ipc_init_ids(ids);
-}
-
-int sem_init_ns(struct ipc_namespace *ns)
-{
- struct ipc_ids *ids;
-
- ids = kmalloc(sizeof(struct ipc_ids), GFP_KERNEL);
- if (ids == NULL)
- return -ENOMEM;
-
- __sem_init_ns(ns, ids);
- return 0;
+ ipc_init_ids(&ns->ids[IPC_SEM_IDS]);
}
+#ifdef CONFIG_IPC_NS
void sem_exit_ns(struct ipc_namespace *ns)
{
- struct sem_array *sma;
- int next_id;
- int total, in_use;
-
- down_write(&sem_ids(ns).rw_mutex);
-
- in_use = sem_ids(ns).in_use;
-
- for (total = 0, next_id = 0; total < in_use; next_id++) {
- sma = idr_find(&sem_ids(ns).ipcs_idr, next_id);
- if (sma == NULL)
- continue;
- ipc_lock_by_ptr(&sma->sem_perm);
- freeary(ns, sma);
- total++;
- }
- up_write(&sem_ids(ns).rw_mutex);
-
- kfree(ns->ids[IPC_SEM_IDS]);
- ns->ids[IPC_SEM_IDS] = NULL;
+ free_ipcs(ns, &sem_ids(ns), freeary);
}
+#endif
void __init sem_init (void)
{
- __sem_init_ns(&init_ipc_ns, &init_sem_ids);
+ sem_init_ns(&init_ipc_ns);
ipc_init_proc_interface("sysvipc/sem",
" key semid perms nsems uid gid cuid cgid otime ctime\n",
IPC_SEM_IDS, sysvipc_sem_proc_show);
}
-/*
- * This routine is called in the paths where the rw_mutex is held to protect
- * access to the idr tree.
- */
-static inline struct sem_array *sem_lock_check_down(struct ipc_namespace *ns,
- int id)
-{
- struct kern_ipc_perm *ipcp = ipc_lock_check_down(&sem_ids(ns), id);
-
- return container_of(ipcp, struct sem_array, sem_perm);
-}
-
/*
* sem_lock_(check_) routines are called in the paths where the rw_mutex
* is not held.
{
struct kern_ipc_perm *ipcp = ipc_lock(&sem_ids(ns), id);
+ if (IS_ERR(ipcp))
+ return (struct sem_array *)ipcp;
+
return container_of(ipcp, struct sem_array, sem_perm);
}
{
struct kern_ipc_perm *ipcp = ipc_lock_check(&sem_ids(ns), id);
+ if (IS_ERR(ipcp))
+ return (struct sem_array *)ipcp;
+
return container_of(ipcp, struct sem_array, sem_perm);
}
+static inline void sem_lock_and_putref(struct sem_array *sma)
+{
+ ipc_lock_by_ptr(&sma->sem_perm);
+ ipc_rcu_putref(sma);
+}
+
+static inline void sem_getref_and_unlock(struct sem_array *sma)
+{
+ ipc_rcu_getref(sma);
+ ipc_unlock(&(sma)->sem_perm);
+}
+
+static inline void sem_putref(struct sem_array *sma)
+{
+ ipc_lock_by_ptr(&sma->sem_perm);
+ ipc_rcu_putref(sma);
+ ipc_unlock(&(sma)->sem_perm);
+}
+
static inline void sem_rmid(struct ipc_namespace *ns, struct sem_array *s)
{
ipc_rmid(&sem_ids(ns), &s->sem_perm);
}
ns->used_sems += nsems;
- sma->sem_perm.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;
* as a writer and the spinlock for this semaphore set hold. sem_ids.rw_mutex
* remains locked on exit.
*/
-static void freeary(struct ipc_namespace *ns, struct sem_array *sma)
+static void freeary(struct ipc_namespace *ns, struct kern_ipc_perm *ipcp)
{
struct sem_undo *un;
struct sem_queue *q;
+ struct sem_array *sma = container_of(ipcp, struct sem_array, sem_perm);
/* Invalidate the existing undo structures for this semaphore set.
* (They will be freed without any further action in exit_sem()
}
}
-static int semctl_nolock(struct ipc_namespace *ns, int semid, int semnum,
- int cmd, int version, union semun arg)
+static int semctl_nolock(struct ipc_namespace *ns, int semid,
+ int cmd, int version, union semun arg)
{
int err = -EINVAL;
struct sem_array *sma;
return -EFAULT;
return (max_id < 0) ? 0: max_id;
}
+ case IPC_STAT:
case SEM_STAT:
{
struct semid64_ds tbuf;
int id;
- sma = sem_lock(ns, semid);
- if (IS_ERR(sma))
- return PTR_ERR(sma);
+ if (cmd == SEM_STAT) {
+ sma = sem_lock(ns, semid);
+ if (IS_ERR(sma))
+ return PTR_ERR(sma);
+ id = sma->sem_perm.id;
+ } else {
+ sma = sem_lock_check(ns, semid);
+ if (IS_ERR(sma))
+ return PTR_ERR(sma);
+ id = 0;
+ }
err = -EACCES;
if (ipcperms (&sma->sem_perm, S_IRUGO))
if (err)
goto out_unlock;
- id = sma->sem_perm.id;
-
memset(&tbuf, 0, sizeof(tbuf));
kernel_to_ipc64_perm(&sma->sem_perm, &tbuf.sem_perm);
int i;
if(nsems > SEMMSL_FAST) {
- ipc_rcu_getref(sma);
- sem_unlock(sma);
+ sem_getref_and_unlock(sma);
sem_io = ipc_alloc(sizeof(ushort)*nsems);
if(sem_io == NULL) {
- ipc_lock_by_ptr(&sma->sem_perm);
- ipc_rcu_putref(sma);
- sem_unlock(sma);
+ sem_putref(sma);
return -ENOMEM;
}
- ipc_lock_by_ptr(&sma->sem_perm);
- ipc_rcu_putref(sma);
+ sem_lock_and_putref(sma);
if (sma->sem_perm.deleted) {
sem_unlock(sma);
err = -EIDRM;
int i;
struct sem_undo *un;
- ipc_rcu_getref(sma);
- sem_unlock(sma);
+ sem_getref_and_unlock(sma);
if(nsems > SEMMSL_FAST) {
sem_io = ipc_alloc(sizeof(ushort)*nsems);
if(sem_io == NULL) {
- ipc_lock_by_ptr(&sma->sem_perm);
- ipc_rcu_putref(sma);
- sem_unlock(sma);
+ sem_putref(sma);
return -ENOMEM;
}
}
if (copy_from_user (sem_io, arg.array, nsems*sizeof(ushort))) {
- ipc_lock_by_ptr(&sma->sem_perm);
- ipc_rcu_putref(sma);
- sem_unlock(sma);
+ sem_putref(sma);
err = -EFAULT;
goto out_free;
}
for (i = 0; i < nsems; i++) {
if (sem_io[i] > SEMVMX) {
- ipc_lock_by_ptr(&sma->sem_perm);
- ipc_rcu_putref(sma);
- sem_unlock(sma);
+ sem_putref(sma);
err = -ERANGE;
goto out_free;
}
}
- ipc_lock_by_ptr(&sma->sem_perm);
- ipc_rcu_putref(sma);
+ sem_lock_and_putref(sma);
if (sma->sem_perm.deleted) {
sem_unlock(sma);
err = -EIDRM;
err = 0;
goto out_unlock;
}
- case IPC_STAT:
- {
- struct semid64_ds tbuf;
- 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;
- tbuf.sem_nsems = sma->sem_nsems;
- sem_unlock(sma);
- if (copy_semid_to_user (arg.buf, &tbuf, version))
- return -EFAULT;
- return 0;
- }
/* GETVAL, GETPID, GETNCTN, GETZCNT, SETVAL: fall-through */
}
err = -EINVAL;
return err;
}
-struct sem_setbuf {
- uid_t uid;
- gid_t gid;
- mode_t mode;
-};
-
-static inline unsigned long copy_semid_from_user(struct sem_setbuf *out, void __user *buf, int version)
+static inline unsigned long
+copy_semid_from_user(struct semid64_ds *out, void __user *buf, int version)
{
switch(version) {
case IPC_64:
- {
- struct semid64_ds tbuf;
-
- if(copy_from_user(&tbuf, buf, sizeof(tbuf)))
+ if (copy_from_user(out, buf, sizeof(*out)))
return -EFAULT;
-
- out->uid = tbuf.sem_perm.uid;
- out->gid = tbuf.sem_perm.gid;
- out->mode = tbuf.sem_perm.mode;
-
return 0;
- }
case IPC_OLD:
{
struct semid_ds tbuf_old;
if(copy_from_user(&tbuf_old, buf, sizeof(tbuf_old)))
return -EFAULT;
- out->uid = tbuf_old.sem_perm.uid;
- out->gid = tbuf_old.sem_perm.gid;
- out->mode = tbuf_old.sem_perm.mode;
+ out->sem_perm.uid = tbuf_old.sem_perm.uid;
+ out->sem_perm.gid = tbuf_old.sem_perm.gid;
+ out->sem_perm.mode = tbuf_old.sem_perm.mode;
return 0;
}
}
}
-static int semctl_down(struct ipc_namespace *ns, int semid, int semnum,
- int cmd, int version, union semun arg)
+/*
+ * This function handles some semctl commands which require the rw_mutex
+ * to be held in write mode.
+ * NOTE: no locks must be held, the rw_mutex is taken inside this function.
+ */
+static int semctl_down(struct ipc_namespace *ns, int semid,
+ int cmd, int version, union semun arg)
{
struct sem_array *sma;
int err;
- struct sem_setbuf uninitialized_var(setbuf);
+ struct semid64_ds semid64;
struct kern_ipc_perm *ipcp;
if(cmd == IPC_SET) {
- if(copy_semid_from_user (&setbuf, arg.buf, version))
+ if (copy_semid_from_user(&semid64, arg.buf, version))
return -EFAULT;
}
- sma = sem_lock_check_down(ns, semid);
- if (IS_ERR(sma))
- return PTR_ERR(sma);
-
- ipcp = &sma->sem_perm;
- err = audit_ipc_obj(ipcp);
- if (err)
- goto out_unlock;
+ ipcp = ipcctl_pre_down(&sem_ids(ns), semid, cmd, &semid64.sem_perm, 0);
+ if (IS_ERR(ipcp))
+ return PTR_ERR(ipcp);
- 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;
- goto out_unlock;
- }
+ sma = container_of(ipcp, struct sem_array, sem_perm);
err = security_sem_semctl(sma, cmd);
if (err)
switch(cmd){
case IPC_RMID:
- freeary(ns, sma);
- err = 0;
- break;
+ freeary(ns, ipcp);
+ goto out_up;
case IPC_SET:
- ipcp->uid = setbuf.uid;
- ipcp->gid = setbuf.gid;
- ipcp->mode = (ipcp->mode & ~S_IRWXUGO)
- | (setbuf.mode & S_IRWXUGO);
+ ipc_update_perm(&semid64.sem_perm, ipcp);
sma->sem_ctime = get_seconds();
- sem_unlock(sma);
- err = 0;
break;
default:
- sem_unlock(sma);
err = -EINVAL;
- break;
}
- return err;
out_unlock:
sem_unlock(sma);
+out_up:
+ up_write(&sem_ids(ns).rw_mutex);
return err;
}
switch(cmd) {
case IPC_INFO:
case SEM_INFO:
+ case IPC_STAT:
case SEM_STAT:
- err = semctl_nolock(ns,semid,semnum,cmd,version,arg);
+ err = semctl_nolock(ns, semid, cmd, version, arg);
return err;
case GETALL:
case GETVAL:
case GETPID:
case GETNCNT:
case GETZCNT:
- case IPC_STAT:
case SETVAL:
case SETALL:
err = semctl_main(ns,semid,semnum,cmd,version,arg);
return err;
case IPC_RMID:
case IPC_SET:
- down_write(&sem_ids(ns).rw_mutex);
- err = semctl_down(ns,semid,semnum,cmd,version,arg);
- up_write(&sem_ids(ns).rw_mutex);
+ err = semctl_down(ns, semid, cmd, version, arg);
return err;
default:
return -EINVAL;
return ERR_PTR(PTR_ERR(sma));
nsems = sma->sem_nsems;
- ipc_rcu_getref(sma);
- sem_unlock(sma);
+ sem_getref_and_unlock(sma);
new = kzalloc(sizeof(struct sem_undo) + sizeof(short)*nsems, GFP_KERNEL);
if (!new) {
- ipc_lock_by_ptr(&sma->sem_perm);
- ipc_rcu_putref(sma);
- sem_unlock(sma);
+ sem_putref(sma);
return ERR_PTR(-ENOMEM);
}
new->semadj = (short *) &new[1];
if (un) {
spin_unlock(&ulp->lock);
kfree(new);
- ipc_lock_by_ptr(&sma->sem_perm);
- ipc_rcu_putref(sma);
- sem_unlock(sma);
+ sem_putref(sma);
goto out;
}
- ipc_lock_by_ptr(&sma->sem_perm);
- ipc_rcu_putref(sma);
+ sem_lock_and_putref(sma);
if (sma->sem_perm.deleted) {
sem_unlock(sma);
spin_unlock(&ulp->lock);
undo_list = tsk->sysvsem.undo_list;
if (!undo_list)
return;
+ tsk->sysvsem.undo_list = NULL;
if (!atomic_dec_and_test(&undo_list->refcnt))
return;