Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs

Pull vfs fixes from Al Viro:
 "atomic_open-related fixes (Miklos' series, with EEXIST-related parts
  replaced with fix in fs/namei.c:atomic_open() instead of messing with
  the instances) + race fix in autofs + leak on failure exit in 9p"

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs:
  9p: don't forget to destroy inode cache if fscache registration fails
  atomic_open: take care of EEXIST in no-open case with O_CREAT|O_EXCL in fs/namei.c
  vfs: don't set FILE_CREATED before calling ->atomic_open()
  nfs: set FILE_CREATED
  gfs2: set FILE_CREATED
  cifs: fix filp leak in cifs_atomic_open()
  vfs: improve i_op->atomic_open() documentation
  autofs4: close the races around autofs4_notify_daemon()

1 files changed, 22 insertions, 12 deletions

diff --git a/fs/namei.c b/fs/namei.c
index 0dc4cbf21f3..645268f23eb 100644
--- a/fs/namei.c
+++ b/fs/namei.c
@@ -2656,6 +2656,7 @@ static int atomic_open(struct nameidata *nd, struct dentry *dentry,
 	int acc_mode;
 	int create_error = 0;
 	struct dentry *const DENTRY_NOT_SET = (void *) -1UL;
+	bool excl;
 
 	BUG_ON(dentry->d_inode);
 
@@ -2669,10 +2670,9 @@ static int atomic_open(struct nameidata *nd, struct dentry *dentry,
 	if ((open_flag & O_CREAT) && !IS_POSIXACL(dir))
 		mode &= ~current_umask();
 
-	if ((open_flag & (O_EXCL | O_CREAT)) == (O_EXCL | O_CREAT)) {
+	excl = (open_flag & (O_EXCL | O_CREAT)) == (O_EXCL | O_CREAT);
+	if (excl)
 		open_flag &= ~O_TRUNC;
-		*opened |= FILE_CREATED;
-	}
 
 	/*
 	 * Checking write permission is tricky, bacuse we don't know if we are
@@ -2725,12 +2725,6 @@ static int atomic_open(struct nameidata *nd, struct dentry *dentry,
 		goto out;
 	}
 
-	acc_mode = op->acc_mode;
-	if (*opened & FILE_CREATED) {
-		fsnotify_create(dir, dentry);
-		acc_mode = MAY_OPEN;
-	}
-
 	if (error) {	/* returned 1, that is */
 		if (WARN_ON(file->f_path.dentry == DENTRY_NOT_SET)) {
 			error = -EIO;
@@ -2740,9 +2734,19 @@ static int atomic_open(struct nameidata *nd, struct dentry *dentry,
 			dput(dentry);
 			dentry = file->f_path.dentry;
 		}
-		if (create_error && dentry->d_inode == NULL) {
-			error = create_error;
-			goto out;
+		if (*opened & FILE_CREATED)
+			fsnotify_create(dir, dentry);
+		if (!dentry->d_inode) {
+			WARN_ON(*opened & FILE_CREATED);
+			if (create_error) {
+				error = create_error;
+				goto out;
+			}
+		} else {
+			if (excl && !(*opened & FILE_CREATED)) {
+				error = -EEXIST;
+				goto out;
+			}
 		}
 		goto looked_up;
 	}
@@ -2751,6 +2755,12 @@ static int atomic_open(struct nameidata *nd, struct dentry *dentry,
 	 * We didn't have the inode before the open, so check open permission
 	 * here.
 	 */
+	acc_mode = op->acc_mode;
+	if (*opened & FILE_CREATED) {
+		WARN_ON(!(open_flag & O_CREAT));
+		fsnotify_create(dir, dentry);
+		acc_mode = MAY_OPEN;
+	}
 	error = may_open(&file->f_path, acc_mode, open_flag);
 	if (error)
 		fput(file);