Switch open_exec() and sys_uselib() to do_open_filp()

... and make path_lookup_open() static

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>

fs/exec.c

@@ -105,36 +105,28 @@ static inline void put_binfmt(struct linux_binfmt * fmt)
 SYSCALL_DEFINE1(uselib, const char __user *, library)
 {
 	struct file *file;
-	struct nameidata nd;
 	char *tmp = getname(library);
 	int error = PTR_ERR(tmp);
 
-	if (!IS_ERR(tmp)) {
-		error = path_lookup_open(AT_FDCWD, tmp,
-					 LOOKUP_FOLLOW, &nd,
-					 FMODE_READ|FMODE_EXEC);
-		putname(tmp);
-	}
-	if (error)
+	if (IS_ERR(tmp))
 		goto out;
 
-	error = -EINVAL;
-	if (!S_ISREG(nd.path.dentry->d_inode->i_mode))
-		goto exit;
-
-	error = -EACCES;
-	if (nd.path.mnt->mnt_flags & MNT_NOEXEC)
-		goto exit;
-
-	error = may_open(&nd.path, MAY_READ | MAY_EXEC | MAY_OPEN, 0);
-	if (error)
-		goto exit;
-
-	file = nameidata_to_filp(&nd, O_RDONLY|O_LARGEFILE);
+	file = do_filp_open(AT_FDCWD, tmp,
+				O_LARGEFILE | O_RDONLY | FMODE_EXEC, 0,
+				MAY_READ | MAY_EXEC | MAY_OPEN);
+	putname(tmp);
 	error = PTR_ERR(file);
 	if (IS_ERR(file))
 		goto out;
 
+	error = -EINVAL;
+	if (!S_ISREG(file->f_path.dentry->d_inode->i_mode))
+		goto exit;
+
+	error = -EACCES;
+	if (file->f_path.mnt->mnt_flags & MNT_NOEXEC)
+		goto exit;
+
 	fsnotify_open(file->f_path.dentry);
 
 	error = -ENOEXEC;
@@ -156,13 +148,10 @@ SYSCALL_DEFINE1(uselib, const char __user *, library)
 		}
 		read_unlock(&binfmt_lock);
 	}
+exit:
 	fput(file);
 out:
   	return error;
-exit:
-	release_open_intent(&nd);
-	path_put(&nd.path);
-	goto out;
 }
 
 #ifdef CONFIG_MMU
@@ -657,44 +646,33 @@ EXPORT_SYMBOL(setup_arg_pages);
 
 struct file *open_exec(const char *name)
 {
-	struct nameidata nd;
 	struct file *file;
 	int err;
 
-	err = path_lookup_open(AT_FDCWD, name, LOOKUP_FOLLOW, &nd,
-				FMODE_READ|FMODE_EXEC);
-	if (err)
+	file = do_filp_open(AT_FDCWD, name,
+				O_LARGEFILE | O_RDONLY | FMODE_EXEC, 0,
+				MAY_EXEC | MAY_OPEN);
+	if (IS_ERR(file))
 		goto out;
 
 	err = -EACCES;
-	if (!S_ISREG(nd.path.dentry->d_inode->i_mode))
-		goto out_path_put;
+	if (!S_ISREG(file->f_path.dentry->d_inode->i_mode))
+		goto exit;
 
-	if (nd.path.mnt->mnt_flags & MNT_NOEXEC)
-		goto out_path_put;
-
-	err = may_open(&nd.path, MAY_EXEC | MAY_OPEN, 0);
-	if (err)
-		goto out_path_put;
-
-	file = nameidata_to_filp(&nd, O_RDONLY|O_LARGEFILE);
-	if (IS_ERR(file))
-		return file;
+	if (file->f_path.mnt->mnt_flags & MNT_NOEXEC)
+		goto exit;
 
 	fsnotify_open(file->f_path.dentry);
 
 	err = deny_write_access(file);
-	if (err) {
-		fput(file);
-		goto out;
-	}
+	if (err)
+		goto exit;
 
+out:
 	return file;
 
- out_path_put:
-	release_open_intent(&nd);
-	path_put(&nd.path);
- out:
+exit:
+	fput(file);
 	return ERR_PTR(err);
 }
 EXPORT_SYMBOL(open_exec);

fs/namei.c

@@ -1130,8 +1130,8 @@ int vfs_path_lookup(struct dentry *dentry, struct vfsmount *mnt,
  * @nd: pointer to nameidata
  * @open_flags: open intent flags
  */
-int path_lookup_open(int dfd, const char *name, unsigned int lookup_flags,
-		struct nameidata *nd, int open_flags)
+static int path_lookup_open(int dfd, const char *name,
+		unsigned int lookup_flags, struct nameidata *nd, int open_flags)
 {
 	struct file *filp = get_empty_filp();
 	int err;
@@ -1637,18 +1637,19 @@ static int open_will_write_to_fs(int flag, struct inode *inode)
  * open_to_namei_flags() for more details.
  */
 struct file *do_filp_open(int dfd, const char *pathname,
-		int open_flag, int mode)
+		int open_flag, int mode, int acc_mode)
 {
 	struct file *filp;
 	struct nameidata nd;
-	int acc_mode, error;
+	int error;
 	struct path path;
 	struct dentry *dir;
 	int count = 0;
 	int will_write;
 	int flag = open_to_namei_flags(open_flag);
 
-	acc_mode = MAY_OPEN | ACC_MODE(flag);
+	if (!acc_mode)
+		acc_mode = MAY_OPEN | ACC_MODE(flag);
 
 	/* O_TRUNC implies we need access checks for write permissions */
 	if (flag & O_TRUNC)
@@ -1869,7 +1870,7 @@ do_link:
  */
 struct file *filp_open(const char *filename, int flags, int mode)
 {
-	return do_filp_open(AT_FDCWD, filename, flags, mode);
+	return do_filp_open(AT_FDCWD, filename, flags, mode, 0);
 }
 EXPORT_SYMBOL(filp_open);
 

fs/open.c

@@ -1033,7 +1033,7 @@ long do_sys_open(int dfd, const char __user *filename, int flags, int mode)
 	if (!IS_ERR(tmp)) {
 		fd = get_unused_fd_flags(flags);
 		if (fd >= 0) {
-			struct file *f = do_filp_open(dfd, tmp, flags, mode);
+			struct file *f = do_filp_open(dfd, tmp, flags, mode, 0);
 			if (IS_ERR(f)) {
 				put_unused_fd(fd);
 				fd = PTR_ERR(f);

include/linux/fs.h

@@ -2118,7 +2118,7 @@ extern struct file *create_write_pipe(int flags);
 extern void free_write_pipe(struct file *);
 
 extern struct file *do_filp_open(int dfd, const char *pathname,
-		int open_flag, int mode);
+		int open_flag, int mode, int acc_mode);
 extern int may_open(struct path *, int, int);
 
 extern int kernel_read(struct file *, unsigned long, char *, unsigned long);

include/linux/namei.h

@@ -69,7 +69,6 @@ extern int path_lookup(const char *, unsigned, struct nameidata *);
 extern int vfs_path_lookup(struct dentry *, struct vfsmount *,
 			   const char *, unsigned int, struct nameidata *);
 
-extern int path_lookup_open(int dfd, const char *name, unsigned lookup_flags, struct nameidata *, int open_flags);
 extern struct file *lookup_instantiate_filp(struct nameidata *nd, struct dentry *dentry,
 		int (*open)(struct inode *, struct file *));
 extern struct file *nameidata_to_filp(struct nameidata *nd, int flags);