int (*show)(struct seq_file *, void *);
};
-struct ipc_namespace init_ipc_ns = {
- .kref = {
- .refcount = ATOMIC_INIT(2),
- },
-};
+#ifdef CONFIG_MEMORY_HOTPLUG
-atomic_t nr_ipc_ns = ATOMIC_INIT(1);
+static void ipc_memory_notifier(struct work_struct *work)
+{
+ ipcns_notify(IPCNS_MEMCHANGED);
+}
+static DECLARE_WORK(ipc_memory_wq, ipc_memory_notifier);
-#ifdef CONFIG_MEMORY_HOTPLUG
static int ipc_memory_callback(struct notifier_block *self,
unsigned long action, void *arg)
/*
* This is done by invoking the ipcns notifier chain with the
* IPC_MEMCHANGED event.
+ * In order not to keep the lock on the hotplug memory chain
+ * for too long, queue a work item that will, when waken up,
+ * activate the ipcns notification chain.
+ * No need to keep several ipc work items on the queue.
*/
- ipcns_notify(IPCNS_MEMCHANGED);
+ if (!work_pending(&ipc_memory_wq))
+ schedule_work(&ipc_memory_wq);
break;
case MEM_GOING_ONLINE:
case MEM_GOING_OFFLINE:
ids->seq = 0;
{
int seq_limit = INT_MAX/SEQ_MULTIPLIER;
- if(seq_limit > USHRT_MAX)
- ids->seq_max = USHRT_MAX;
+ if (seq_limit > USHORT_MAX)
+ ids->seq_max = USHORT_MAX;
else
ids->seq_max = seq_limit;
}
iface->ids = ids;
iface->show = show;
- pde = create_proc_entry(path,
- S_IRUGO, /* world readable */
- NULL /* parent dir */);
- if (pde) {
- pde->data = iface;
- pde->proc_fops = &sysvipc_proc_fops;
- } else {
+ pde = proc_create_data(path,
+ S_IRUGO, /* world readable */
+ NULL, /* parent dir */
+ &sysvipc_proc_fops,
+ iface);
+ if (!pde) {
kfree(iface);
}
}
int ipc_addid(struct ipc_ids* ids, struct kern_ipc_perm* new, int size)
{
+ uid_t euid;
+ gid_t egid;
int id, err;
if (size > IPCMNI)
if (ids->in_use >= size)
return -ENOSPC;
+ spin_lock_init(&new->lock);
+ new->deleted = 0;
+ rcu_read_lock();
+ spin_lock(&new->lock);
+
err = idr_get_new(&ids->ipcs_idr, new, &id);
- if (err)
+ if (err) {
+ spin_unlock(&new->lock);
+ rcu_read_unlock();
return err;
+ }
ids->in_use++;
- new->cuid = new->uid = current->euid;
- new->gid = new->cgid = current->egid;
+ current_euid_egid(&euid, &egid);
+ new->cuid = new->uid = euid;
+ new->gid = new->cgid = egid;
new->seq = ids->seq++;
if(ids->seq > ids->seq_max)
ids->seq = 0;
new->id = ipc_buildid(id, new->seq);
- spin_lock_init(&new->lock);
- new->deleted = 0;
- rcu_read_lock();
- spin_lock(&new->lock);
return id;
}
int ipcperms (struct kern_ipc_perm *ipcp, short flag)
{ /* flag will most probably be 0 or S_...UGO from <linux/stat.h> */
- int requested_mode, granted_mode, err;
+ uid_t euid = current_euid();
+ int requested_mode, granted_mode;
- if (unlikely((err = audit_ipc_obj(ipcp))))
- return err;
+ audit_ipc_obj(ipcp);
requested_mode = (flag >> 6) | (flag >> 3) | flag;
granted_mode = ipcp->mode;
- if (current->euid == ipcp->cuid || current->euid == ipcp->uid)
+ if (euid == ipcp->cuid ||
+ euid == ipcp->uid)
granted_mode >>= 6;
else if (in_group_p(ipcp->cgid) || in_group_p(ipcp->gid))
granted_mode >>= 3;
* Look for an id in the ipc ids idr and lock the associated ipc object.
*
* The ipc object is locked on exit.
- *
- * This is the routine that should be called when the rw_mutex is not already
- * held, i.e. idr tree not protected: it protects the idr tree in read mode
- * during the idr_find().
*/
struct kern_ipc_perm *ipc_lock(struct ipc_ids *ids, int id)
struct kern_ipc_perm *out;
int lid = ipcid_to_idx(id);
- down_read(&ids->rw_mutex);
-
rcu_read_lock();
out = idr_find(&ids->ipcs_idr, lid);
if (out == NULL) {
rcu_read_unlock();
- up_read(&ids->rw_mutex);
return ERR_PTR(-EINVAL);
}
- up_read(&ids->rw_mutex);
-
spin_lock(&out->lock);
/* ipc_rmid() may have already freed the ID while ipc_lock
return out;
}
-/**
- * ipc_lock_down - Lock an ipc structure with rw_sem held
- * @ids: IPC identifier set
- * @id: ipc id to look for
- *
- * Look for an id in the ipc ids idr and lock the associated ipc object.
- *
- * The ipc object is locked on exit.
- *
- * This is the routine that should be called when the rw_mutex is already
- * held, i.e. idr tree protected.
- */
-
-struct kern_ipc_perm *ipc_lock_down(struct ipc_ids *ids, int id)
-{
- struct kern_ipc_perm *out;
- int lid = ipcid_to_idx(id);
-
- rcu_read_lock();
- out = idr_find(&ids->ipcs_idr, lid);
- if (out == NULL) {
- rcu_read_unlock();
- return ERR_PTR(-EINVAL);
- }
-
- spin_lock(&out->lock);
-
- /*
- * No need to verify that the structure is still valid since the
- * rw_mutex is held.
- */
- return out;
-}
-
-struct kern_ipc_perm *ipc_lock_check_down(struct ipc_ids *ids, int id)
-{
- struct kern_ipc_perm *out;
-
- out = ipc_lock_down(ids, id);
- if (IS_ERR(out))
- return out;
-
- if (ipc_checkid(out, id)) {
- ipc_unlock(out);
- return ERR_PTR(-EIDRM);
- }
-
- return out;
-}
-
struct kern_ipc_perm *ipc_lock_check(struct ipc_ids *ids, int id)
{
struct kern_ipc_perm *out;
return ipcget_public(ns, ids, ops, params);
}
+/**
+ * ipc_update_perm - update the permissions of an IPC.
+ * @in: the permission given as input.
+ * @out: the permission of the ipc to set.
+ */
+void ipc_update_perm(struct ipc64_perm *in, struct kern_ipc_perm *out)
+{
+ out->uid = in->uid;
+ out->gid = in->gid;
+ out->mode = (out->mode & ~S_IRWXUGO)
+ | (in->mode & S_IRWXUGO);
+}
+
+/**
+ * ipcctl_pre_down - retrieve an ipc and check permissions for some IPC_XXX cmd
+ * @ids: the table of ids where to look for the ipc
+ * @id: the id of the ipc to retrieve
+ * @cmd: the cmd to check
+ * @perm: the permission to set
+ * @extra_perm: one extra permission parameter used by msq
+ *
+ * This function does some common audit and permissions check for some IPC_XXX
+ * cmd and is called from semctl_down, shmctl_down and msgctl_down.
+ * It must be called without any lock held and
+ * - retrieves the ipc with the given id in the given table.
+ * - performs some audit and permission check, depending on the given cmd
+ * - returns the ipc with both ipc and rw_mutex locks held in case of success
+ * or an err-code without any lock held otherwise.
+ */
+struct kern_ipc_perm *ipcctl_pre_down(struct ipc_ids *ids, int id, int cmd,
+ struct ipc64_perm *perm, int extra_perm)
+{
+ struct kern_ipc_perm *ipcp;
+ uid_t euid;
+ int err;
+
+ down_write(&ids->rw_mutex);
+ ipcp = ipc_lock_check(ids, id);
+ if (IS_ERR(ipcp)) {
+ err = PTR_ERR(ipcp);
+ goto out_up;
+ }
+
+ audit_ipc_obj(ipcp);
+ if (cmd == IPC_SET)
+ audit_ipc_set_perm(extra_perm, perm->uid,
+ perm->gid, perm->mode);
+
+ euid = current_euid();
+ if (euid == ipcp->cuid ||
+ euid == ipcp->uid || capable(CAP_SYS_ADMIN))
+ return ipcp;
+
+ err = -EPERM;
+ ipc_unlock(ipcp);
+out_up:
+ up_write(&ids->rw_mutex);
+ return ERR_PTR(err);
+}
+
#ifdef __ARCH_WANT_IPC_PARSE_VERSION
return iface->show(s, it);
}
-static struct seq_operations sysvipc_proc_seqops = {
+static const struct seq_operations sysvipc_proc_seqops = {
.start = sysvipc_proc_start,
.stop = sysvipc_proc_stop,
.next = sysvipc_proc_next,
git://ftp.safe.ca / safe / jmp / linux-2.6 / blobdiff