1 files changed, 67 insertions, 75 deletions

diff --git a/ipc/mqueue.c b/ipc/mqueue.c
index f8e54f5b9080..6b97e2466fad 100644
--- a/ipc/mqueue.c
+++ b/ipc/mqueue.c
@@ -142,7 +142,6 @@ static int msg_insert(struct msg_msg *msg, struct mqueue_inode_info *info)
 		leaf = kmalloc(sizeof(*leaf), GFP_ATOMIC);
 		if (!leaf)
 			return -ENOMEM;
-		rb_init_node(&leaf->rb_node);
 		INIT_LIST_HEAD(&leaf->msg_list);
 		info->qsize += sizeof(*leaf);
 	}
@@ -726,7 +725,6 @@ static struct file *do_create(struct ipc_namespace *ipc_ns, struct inode *dir,
 			struct mq_attr *attr)
 {
 	const struct cred *cred = current_cred();
-	struct file *result;
 	int ret;
 
 	if (attr) {
@@ -748,21 +746,11 @@ static struct file *do_create(struct ipc_namespace *ipc_ns, struct inode *dir,
 	}
 
 	mode &= ~current_umask();
-	ret = mnt_want_write(path->mnt);
-	if (ret)
-		return ERR_PTR(ret);
 	ret = vfs_create(dir, path->dentry, mode, true);
 	path->dentry->d_fsdata = NULL;
-	if (!ret)
-		result = dentry_open(path, oflag, cred);
-	else
-		result = ERR_PTR(ret);
-	/*
-	 * dentry_open() took a persistent mnt_want_write(),
-	 * so we can now drop this one.
-	 */
-	mnt_drop_write(path->mnt);
-	return result;
+	if (ret)
+		return ERR_PTR(ret);
+	return dentry_open(path, oflag, cred);
 }
 
 /* Opens existing queue */
@@ -788,7 +776,9 @@ SYSCALL_DEFINE4(mq_open, const char __user *, u_name, int, oflag, umode_t, mode,
 	struct mq_attr attr;
 	int fd, error;
 	struct ipc_namespace *ipc_ns = current->nsproxy->ipc_ns;
-	struct dentry *root = ipc_ns->mq_mnt->mnt_root;
+	struct vfsmount *mnt = ipc_ns->mq_mnt;
+	struct dentry *root = mnt->mnt_root;
+	int ro;
 
 	if (u_attr && copy_from_user(&attr, u_attr, sizeof(struct mq_attr)))
 		return -EFAULT;
@@ -802,6 +792,7 @@ SYSCALL_DEFINE4(mq_open, const char __user *, u_name, int, oflag, umode_t, mode,
 	if (fd < 0)
 		goto out_putname;
 
+	ro = mnt_want_write(mnt);	/* we'll drop it in any case */
 	error = 0;
 	mutex_lock(&root->d_inode->i_mutex);
 	path.dentry = lookup_one_len(name, root, strlen(name));
@@ -809,7 +800,7 @@ SYSCALL_DEFINE4(mq_open, const char __user *, u_name, int, oflag, umode_t, mode,
 		error = PTR_ERR(path.dentry);
 		goto out_putfd;
 	}
-	path.mnt = mntget(ipc_ns->mq_mnt);
+	path.mnt = mntget(mnt);
 
 	if (oflag & O_CREAT) {
 		if (path.dentry->d_inode) {	/* entry already exists */
@@ -820,6 +811,10 @@ SYSCALL_DEFINE4(mq_open, const char __user *, u_name, int, oflag, umode_t, mode,
 			}
 			filp = do_open(&path, oflag);
 		} else {
+			if (ro) {
+				error = ro;
+				goto out;
+			}
 			filp = do_create(ipc_ns, root->d_inode,
 						&path, oflag, mode,
 						u_attr ? &attr : NULL);
@@ -845,6 +840,7 @@ out_putfd:
 		fd = error;
 	}
 	mutex_unlock(&root->d_inode->i_mutex);
+	mnt_drop_write(mnt);
 out_putname:
 	putname(name);
 	return fd;
@@ -857,40 +853,38 @@ SYSCALL_DEFINE1(mq_unlink, const char __user *, u_name)
 	struct dentry *dentry;
 	struct inode *inode = NULL;
 	struct ipc_namespace *ipc_ns = current->nsproxy->ipc_ns;
+	struct vfsmount *mnt = ipc_ns->mq_mnt;
 
 	name = getname(u_name);
 	if (IS_ERR(name))
 		return PTR_ERR(name);
 
-	mutex_lock_nested(&ipc_ns->mq_mnt->mnt_root->d_inode->i_mutex,
-			I_MUTEX_PARENT);
-	dentry = lookup_one_len(name, ipc_ns->mq_mnt->mnt_root, strlen(name));
+	err = mnt_want_write(mnt);
+	if (err)
+		goto out_name;
+	mutex_lock_nested(&mnt->mnt_root->d_inode->i_mutex, I_MUTEX_PARENT);
+	dentry = lookup_one_len(name, mnt->mnt_root, strlen(name));
 	if (IS_ERR(dentry)) {
 		err = PTR_ERR(dentry);
 		goto out_unlock;
 	}
 
-	if (!dentry->d_inode) {
-		err = -ENOENT;
-		goto out_err;
-	}
-
 	inode = dentry->d_inode;
-	if (inode)
+	if (!inode) {
+		err = -ENOENT;
+	} else {
 		ihold(inode);
-	err = mnt_want_write(ipc_ns->mq_mnt);
-	if (err)
-		goto out_err;
-	err = vfs_unlink(dentry->d_parent->d_inode, dentry);
-	mnt_drop_write(ipc_ns->mq_mnt);
-out_err:
+		err = vfs_unlink(dentry->d_parent->d_inode, dentry);
+	}
 	dput(dentry);
 
 out_unlock:
-	mutex_unlock(&ipc_ns->mq_mnt->mnt_root->d_inode->i_mutex);
-	putname(name);
+	mutex_unlock(&mnt->mnt_root->d_inode->i_mutex);
 	if (inode)
 		iput(inode);
+	mnt_drop_write(mnt);
+out_name:
+	putname(name);
 
 	return err;
 }
@@ -949,7 +943,7 @@ SYSCALL_DEFINE5(mq_timedsend, mqd_t, mqdes, const char __user *, u_msg_ptr,
 		size_t, msg_len, unsigned int, msg_prio,
 		const struct timespec __user *, u_abs_timeout)
 {
-	struct file *filp;
+	struct fd f;
 	struct inode *inode;
 	struct ext_wait_queue wait;
 	struct ext_wait_queue *receiver;
@@ -972,21 +966,21 @@ SYSCALL_DEFINE5(mq_timedsend, mqd_t, mqdes, const char __user *, u_msg_ptr,
 
 	audit_mq_sendrecv(mqdes, msg_len, msg_prio, timeout ? &ts : NULL);
 
-	filp = fget(mqdes);
-	if (unlikely(!filp)) {
+	f = fdget(mqdes);
+	if (unlikely(!f.file)) {
 		ret = -EBADF;
 		goto out;
 	}
 
-	inode = filp->f_path.dentry->d_inode;
-	if (unlikely(filp->f_op != &mqueue_file_operations)) {
+	inode = f.file->f_path.dentry->d_inode;
+	if (unlikely(f.file->f_op != &mqueue_file_operations)) {
 		ret = -EBADF;
 		goto out_fput;
 	}
 	info = MQUEUE_I(inode);
-	audit_inode(NULL, filp->f_path.dentry);
+	audit_inode(NULL, f.file->f_path.dentry);
 
-	if (unlikely(!(filp->f_mode & FMODE_WRITE))) {
+	if (unlikely(!(f.file->f_mode & FMODE_WRITE))) {
 		ret = -EBADF;
 		goto out_fput;
 	}
@@ -1018,7 +1012,6 @@ SYSCALL_DEFINE5(mq_timedsend, mqd_t, mqdes, const char __user *, u_msg_ptr,
 
 	if (!info->node_cache && new_leaf) {
 		/* Save our speculative allocation into the cache */
-		rb_init_node(&new_leaf->rb_node);
 		INIT_LIST_HEAD(&new_leaf->msg_list);
 		info->node_cache = new_leaf;
 		info->qsize += sizeof(*new_leaf);
@@ -1028,7 +1021,7 @@ SYSCALL_DEFINE5(mq_timedsend, mqd_t, mqdes, const char __user *, u_msg_ptr,
 	}
 
 	if (info->attr.mq_curmsgs == info->attr.mq_maxmsg) {
-		if (filp->f_flags & O_NONBLOCK) {
+		if (f.file->f_flags & O_NONBLOCK) {
 			ret = -EAGAIN;
 		} else {
 			wait.task = current;
@@ -1061,7 +1054,7 @@ out_free:
 	if (ret)
 		free_msg(msg_ptr);
 out_fput:
-	fput(filp);
+	fdput(f);
 out:
 	return ret;
 }
@@ -1072,7 +1065,7 @@ SYSCALL_DEFINE5(mq_timedreceive, mqd_t, mqdes, char __user *, u_msg_ptr,
 {
 	ssize_t ret;
 	struct msg_msg *msg_ptr;
-	struct file *filp;
+	struct fd f;
 	struct inode *inode;
 	struct mqueue_inode_info *info;
 	struct ext_wait_queue wait;
@@ -1089,21 +1082,21 @@ SYSCALL_DEFINE5(mq_timedreceive, mqd_t, mqdes, char __user *, u_msg_ptr,
 
 	audit_mq_sendrecv(mqdes, msg_len, 0, timeout ? &ts : NULL);
 
-	filp = fget(mqdes);
-	if (unlikely(!filp)) {
+	f = fdget(mqdes);
+	if (unlikely(!f.file)) {
 		ret = -EBADF;
 		goto out;
 	}
 
-	inode = filp->f_path.dentry->d_inode;
-	if (unlikely(filp->f_op != &mqueue_file_operations)) {
+	inode = f.file->f_path.dentry->d_inode;
+	if (unlikely(f.file->f_op != &mqueue_file_operations)) {
 		ret = -EBADF;
 		goto out_fput;
 	}
 	info = MQUEUE_I(inode);
-	audit_inode(NULL, filp->f_path.dentry);
+	audit_inode(NULL, f.file->f_path.dentry);
 
-	if (unlikely(!(filp->f_mode & FMODE_READ))) {
+	if (unlikely(!(f.file->f_mode & FMODE_READ))) {
 		ret = -EBADF;
 		goto out_fput;
 	}
@@ -1126,7 +1119,6 @@ SYSCALL_DEFINE5(mq_timedreceive, mqd_t, mqdes, char __user *, u_msg_ptr,
 
 	if (!info->node_cache && new_leaf) {
 		/* Save our speculative allocation into the cache */
-		rb_init_node(&new_leaf->rb_node);
 		INIT_LIST_HEAD(&new_leaf->msg_list);
 		info->node_cache = new_leaf;
 		info->qsize += sizeof(*new_leaf);
@@ -1135,7 +1127,7 @@ SYSCALL_DEFINE5(mq_timedreceive, mqd_t, mqdes, char __user *, u_msg_ptr,
 	}
 
 	if (info->attr.mq_curmsgs == 0) {
-		if (filp->f_flags & O_NONBLOCK) {
+		if (f.file->f_flags & O_NONBLOCK) {
 			spin_unlock(&info->lock);
 			ret = -EAGAIN;
 		} else {
@@ -1165,7 +1157,7 @@ SYSCALL_DEFINE5(mq_timedreceive, mqd_t, mqdes, char __user *, u_msg_ptr,
 		free_msg(msg_ptr);
 	}
 out_fput:
-	fput(filp);
+	fdput(f);
 out:
 	return ret;
 }
@@ -1179,7 +1171,7 @@ SYSCALL_DEFINE2(mq_notify, mqd_t, mqdes,
 		const struct sigevent __user *, u_notification)
 {
 	int ret;
-	struct file *filp;
+	struct fd f;
 	struct sock *sock;
 	struct inode *inode;
 	struct sigevent notification;
@@ -1225,13 +1217,13 @@ SYSCALL_DEFINE2(mq_notify, mqd_t, mqdes,
 			skb_put(nc, NOTIFY_COOKIE_LEN);
 			/* and attach it to the socket */
 retry:
-			filp = fget(notification.sigev_signo);
-			if (!filp) {
+			f = fdget(notification.sigev_signo);
+			if (!f.file) {
 				ret = -EBADF;
 				goto out;
 			}
-			sock = netlink_getsockbyfilp(filp);
-			fput(filp);
+			sock = netlink_getsockbyfilp(f.file);
+			fdput(f);
 			if (IS_ERR(sock)) {
 				ret = PTR_ERR(sock);
 				sock = NULL;
@@ -1250,14 +1242,14 @@ retry:
 		}
 	}
 
-	filp = fget(mqdes);
-	if (!filp) {
+	f = fdget(mqdes);
+	if (!f.file) {
 		ret = -EBADF;
 		goto out;
 	}
 
-	inode = filp->f_path.dentry->d_inode;
-	if (unlikely(filp->f_op != &mqueue_file_operations)) {
+	inode = f.file->f_path.dentry->d_inode;
+	if (unlikely(f.file->f_op != &mqueue_file_operations)) {
 		ret = -EBADF;
 		goto out_fput;
 	}
@@ -1297,7 +1289,7 @@ retry:
 	}
 	spin_unlock(&info->lock);
 out_fput:
-	fput(filp);
+	fdput(f);
 out:
 	if (sock) {
 		netlink_detachskb(sock, nc);
@@ -1313,7 +1305,7 @@ SYSCALL_DEFINE3(mq_getsetattr, mqd_t, mqdes,
 {
 	int ret;
 	struct mq_attr mqstat, omqstat;
-	struct file *filp;
+	struct fd f;
 	struct inode *inode;
 	struct mqueue_inode_info *info;
 
@@ -1324,14 +1316,14 @@ SYSCALL_DEFINE3(mq_getsetattr, mqd_t, mqdes,
 			return -EINVAL;
 	}
 
-	filp = fget(mqdes);
-	if (!filp) {
+	f = fdget(mqdes);
+	if (!f.file) {
 		ret = -EBADF;
 		goto out;
 	}
 
-	inode = filp->f_path.dentry->d_inode;
-	if (unlikely(filp->f_op != &mqueue_file_operations)) {
+	inode = f.file->f_path.dentry->d_inode;
+	if (unlikely(f.file->f_op != &mqueue_file_operations)) {
 		ret = -EBADF;
 		goto out_fput;
 	}
@@ -1340,15 +1332,15 @@ SYSCALL_DEFINE3(mq_getsetattr, mqd_t, mqdes,
 	spin_lock(&info->lock);
 
 	omqstat = info->attr;
-	omqstat.mq_flags = filp->f_flags & O_NONBLOCK;
+	omqstat.mq_flags = f.file->f_flags & O_NONBLOCK;
 	if (u_mqstat) {
 		audit_mq_getsetattr(mqdes, &mqstat);
-		spin_lock(&filp->f_lock);
+		spin_lock(&f.file->f_lock);
 		if (mqstat.mq_flags & O_NONBLOCK)
-			filp->f_flags |= O_NONBLOCK;
+			f.file->f_flags |= O_NONBLOCK;
 		else
-			filp->f_flags &= ~O_NONBLOCK;
-		spin_unlock(&filp->f_lock);
+			f.file->f_flags &= ~O_NONBLOCK;
+		spin_unlock(&f.file->f_lock);
 
 		inode->i_atime = inode->i_ctime = CURRENT_TIME;
 	}
@@ -1361,7 +1353,7 @@ SYSCALL_DEFINE3(mq_getsetattr, mqd_t, mqdes,
 		ret = -EFAULT;
 
 out_fput:
-	fput(filp);
+	fdput(f);
 out:
 	return ret;
 }