Update to 3.4-final.
[linux-flexiantxendom0-3.2.10.git] / ipc / mqueue.c
index 035f439..28bd64d 100644 (file)
@@ -32,6 +32,7 @@
 #include <linux/nsproxy.h>
 #include <linux/pid.h>
 #include <linux/ipc_namespace.h>
+#include <linux/user_namespace.h>
 #include <linux/slab.h>
 
 #include <net/sock.h>
@@ -108,107 +109,99 @@ static struct ipc_namespace *get_ns_from_inode(struct inode *inode)
 }
 
 static struct inode *mqueue_get_inode(struct super_block *sb,
-               struct ipc_namespace *ipc_ns, int mode,
+               struct ipc_namespace *ipc_ns, umode_t mode,
                struct mq_attr *attr)
 {
        struct user_struct *u = current_user();
        struct inode *inode;
+       int ret = -ENOMEM;
 
        inode = new_inode(sb);
-       if (inode) {
-               inode->i_ino = get_next_ino();
-               inode->i_mode = mode;
-               inode->i_uid = current_fsuid();
-               inode->i_gid = current_fsgid();
-               inode->i_mtime = inode->i_ctime = inode->i_atime =
-                               CURRENT_TIME;
+       if (!inode)
+               goto err;
 
-               if (S_ISREG(mode)) {
-                       struct mqueue_inode_info *info;
-                       struct task_struct *p = current;
-                       unsigned long mq_bytes, mq_msg_tblsz;
-
-                       inode->i_fop = &mqueue_file_operations;
-                       inode->i_size = FILENT_SIZE;
-                       /* mqueue specific info */
-                       info = MQUEUE_I(inode);
-                       spin_lock_init(&info->lock);
-                       init_waitqueue_head(&info->wait_q);
-                       INIT_LIST_HEAD(&info->e_wait_q[0].list);
-                       INIT_LIST_HEAD(&info->e_wait_q[1].list);
-                       info->notify_owner = NULL;
-                       info->qsize = 0;
-                       info->user = NULL;      /* set when all is ok */
-                       memset(&info->attr, 0, sizeof(info->attr));
-                       info->attr.mq_maxmsg = ipc_ns->mq_msg_max;
-                       info->attr.mq_msgsize = ipc_ns->mq_msgsize_max;
-                       if (attr) {
-                               info->attr.mq_maxmsg = attr->mq_maxmsg;
-                               info->attr.mq_msgsize = attr->mq_msgsize;
-                       }
-                       mq_msg_tblsz = info->attr.mq_maxmsg * sizeof(struct msg_msg *);
-                       info->messages = kmalloc(mq_msg_tblsz, GFP_KERNEL);
-                       if (!info->messages)
-                               goto out_inode;
-
-                       mq_bytes = (mq_msg_tblsz +
-                               (info->attr.mq_maxmsg * info->attr.mq_msgsize));
-
-                       spin_lock(&mq_lock);
-                       if (u->mq_bytes + mq_bytes < u->mq_bytes ||
-                           u->mq_bytes + mq_bytes >
-                           task_rlimit(p, RLIMIT_MSGQUEUE)) {
-                               spin_unlock(&mq_lock);
-                               /* mqueue_evict_inode() releases info->messages */
-                               goto out_inode;
-                       }
-                       u->mq_bytes += mq_bytes;
-                       spin_unlock(&mq_lock);
+       inode->i_ino = get_next_ino();
+       inode->i_mode = mode;
+       inode->i_uid = current_fsuid();
+       inode->i_gid = current_fsgid();
+       inode->i_mtime = inode->i_ctime = inode->i_atime = CURRENT_TIME;
+
+       if (S_ISREG(mode)) {
+               struct mqueue_inode_info *info;
+               unsigned long mq_bytes, mq_msg_tblsz;
+
+               inode->i_fop = &mqueue_file_operations;
+               inode->i_size = FILENT_SIZE;
+               /* mqueue specific info */
+               info = MQUEUE_I(inode);
+               spin_lock_init(&info->lock);
+               init_waitqueue_head(&info->wait_q);
+               INIT_LIST_HEAD(&info->e_wait_q[0].list);
+               INIT_LIST_HEAD(&info->e_wait_q[1].list);
+               info->notify_owner = NULL;
+               info->qsize = 0;
+               info->user = NULL;      /* set when all is ok */
+               memset(&info->attr, 0, sizeof(info->attr));
+               info->attr.mq_maxmsg = ipc_ns->mq_msg_max;
+               info->attr.mq_msgsize = ipc_ns->mq_msgsize_max;
+               if (attr) {
+                       info->attr.mq_maxmsg = attr->mq_maxmsg;
+                       info->attr.mq_msgsize = attr->mq_msgsize;
+               }
+               mq_msg_tblsz = info->attr.mq_maxmsg * sizeof(struct msg_msg *);
+               info->messages = kmalloc(mq_msg_tblsz, GFP_KERNEL);
+               if (!info->messages)
+                       goto out_inode;
 
-                       /* all is ok */
-                       info->user = get_uid(u);
-               } else if (S_ISDIR(mode)) {
-                       inc_nlink(inode);
-                       /* Some things misbehave if size == 0 on a directory */
-                       inode->i_size = 2 * DIRENT_SIZE;
-                       inode->i_op = &mqueue_dir_inode_operations;
-                       inode->i_fop = &simple_dir_operations;
+               mq_bytes = (mq_msg_tblsz +
+                       (info->attr.mq_maxmsg * info->attr.mq_msgsize));
+
+               spin_lock(&mq_lock);
+               if (u->mq_bytes + mq_bytes < u->mq_bytes ||
+                   u->mq_bytes + mq_bytes > rlimit(RLIMIT_MSGQUEUE)) {
+                       spin_unlock(&mq_lock);
+                       /* mqueue_evict_inode() releases info->messages */
+                       ret = -EMFILE;
+                       goto out_inode;
                }
+               u->mq_bytes += mq_bytes;
+               spin_unlock(&mq_lock);
+
+               /* all is ok */
+               info->user = get_uid(u);
+       } else if (S_ISDIR(mode)) {
+               inc_nlink(inode);
+               /* Some things misbehave if size == 0 on a directory */
+               inode->i_size = 2 * DIRENT_SIZE;
+               inode->i_op = &mqueue_dir_inode_operations;
+               inode->i_fop = &simple_dir_operations;
        }
+
        return inode;
 out_inode:
        iput(inode);
-       return NULL;
+err:
+       return ERR_PTR(ret);
 }
 
 static int mqueue_fill_super(struct super_block *sb, void *data, int silent)
 {
        struct inode *inode;
        struct ipc_namespace *ns = data;
-       int error;
 
        sb->s_blocksize = PAGE_CACHE_SIZE;
        sb->s_blocksize_bits = PAGE_CACHE_SHIFT;
        sb->s_magic = MQUEUE_MAGIC;
        sb->s_op = &mqueue_super_ops;
 
-       inode = mqueue_get_inode(sb, ns, S_IFDIR | S_ISVTX | S_IRWXUGO,
-                               NULL);
-       if (!inode) {
-               error = -ENOMEM;
-               goto out;
-       }
-
-       sb->s_root = d_alloc_root(inode);
-       if (!sb->s_root) {
-               iput(inode);
-               error = -ENOMEM;
-               goto out;
-       }
-       error = 0;
+       inode = mqueue_get_inode(sb, ns, S_IFDIR | S_ISVTX | S_IRWXUGO, NULL);
+       if (IS_ERR(inode))
+               return PTR_ERR(inode);
 
-out:
-       return error;
+       sb->s_root = d_make_root(inode);
+       if (!sb->s_root)
+               return -ENOMEM;
+       return 0;
 }
 
 static struct dentry *mqueue_mount(struct file_system_type *fs_type,
@@ -237,11 +230,17 @@ static struct inode *mqueue_alloc_inode(struct super_block *sb)
        return &ei->vfs_inode;
 }
 
-static void mqueue_destroy_inode(struct inode *inode)
+static void mqueue_i_callback(struct rcu_head *head)
 {
+       struct inode *inode = container_of(head, struct inode, i_rcu);
        kmem_cache_free(mqueue_inode_cachep, MQUEUE_I(inode));
 }
 
+static void mqueue_destroy_inode(struct inode *inode)
+{
+       call_rcu(&inode->i_rcu, mqueue_i_callback);
+}
+
 static void mqueue_evict_inode(struct inode *inode)
 {
        struct mqueue_inode_info *info;
@@ -286,7 +285,7 @@ static void mqueue_evict_inode(struct inode *inode)
 }
 
 static int mqueue_create(struct inode *dir, struct dentry *dentry,
-                               int mode, struct nameidata *nd)
+                               umode_t mode, struct nameidata *nd)
 {
        struct inode *inode;
        struct mq_attr *attr = dentry->d_fsdata;
@@ -308,8 +307,8 @@ static int mqueue_create(struct inode *dir, struct dentry *dentry,
        spin_unlock(&mq_lock);
 
        inode = mqueue_get_inode(dir->i_sb, ipc_ns, mode, attr);
-       if (!inode) {
-               error = -ENOMEM;
+       if (IS_ERR(inode)) {
+               error = PTR_ERR(inode);
                spin_lock(&mq_lock);
                ipc_ns->mq_queues_count--;
                goto out_unlock;
@@ -439,8 +438,8 @@ static int wq_sleep(struct mqueue_inode_info *info, int sr,
                set_current_state(TASK_INTERRUPTIBLE);
 
                spin_unlock(&info->lock);
-               time = schedule_hrtimeout_range_clock(timeout,
-                   HRTIMER_MODE_ABS, 0, CLOCK_REALTIME);
+               time = schedule_hrtimeout_range_clock(timeout, 0,
+                       HRTIMER_MODE_ABS, CLOCK_REALTIME);
 
                while (ewp->state == STATE_PENDING)
                        cpu_relax();
@@ -533,9 +532,13 @@ static void __do_notify(struct mqueue_inode_info *info)
                        sig_i.si_errno = 0;
                        sig_i.si_code = SI_MESGQ;
                        sig_i.si_value = info->notify.sigev_value;
+                       /* map current pid/uid into info->owner's namespaces */
+                       rcu_read_lock();
                        sig_i.si_pid = task_tgid_nr_ns(current,
                                                ns_of_pid(info->notify_owner));
-                       sig_i.si_uid = current_uid();
+                       sig_i.si_uid = user_ns_map_uid(info->user->user_ns,
+                                               current_cred(), current_uid());
+                       rcu_read_unlock();
 
                        kill_pid_info(info->notify.sigev_signo,
                                      &sig_i, info->notify_owner);
@@ -601,7 +604,7 @@ static int mq_attr_ok(struct ipc_namespace *ipc_ns, struct mq_attr *attr)
  * Invoked when creating a new queue via sys_mq_open
  */
 static struct file *do_create(struct ipc_namespace *ipc_ns, struct dentry *dir,
-                       struct dentry *dentry, int oflag, mode_t mode,
+                       struct dentry *dentry, int oflag, umode_t mode,
                        struct mq_attr *attr)
 {
        const struct cred *cred = current_cred();
@@ -670,7 +673,7 @@ err:
        return ERR_PTR(ret);
 }
 
-SYSCALL_DEFINE4(mq_open, const char __user *, u_name, int, oflag, mode_t, mode,
+SYSCALL_DEFINE4(mq_open, const char __user *, u_name, int, oflag, umode_t, mode,
                struct mq_attr __user *, u_attr)
 {
        struct dentry *dentry;
@@ -1259,7 +1262,7 @@ void mq_clear_sbinfo(struct ipc_namespace *ns)
 
 void mq_put_mnt(struct ipc_namespace *ns)
 {
-       mntput(ns->mq_mnt);
+       kern_unmount(ns->mq_mnt);
 }
 
 static int __init init_mqueue_fs(void)
@@ -1281,11 +1284,9 @@ static int __init init_mqueue_fs(void)
 
        spin_lock_init(&mq_lock);
 
-       init_ipc_ns.mq_mnt = kern_mount_data(&mqueue_fs_type, &init_ipc_ns);
-       if (IS_ERR(init_ipc_ns.mq_mnt)) {
-               error = PTR_ERR(init_ipc_ns.mq_mnt);
+       error = mq_init_ns(&init_ipc_ns);
+       if (error)
                goto out_filesystem;
-       }
 
        return 0;