[PATCH v3 2/6] locks: consolidate checks for compatible filp->f_mode values in setlk handlers

[Jeff Layton <jlayton@redhat.com>]

Move this check into the posix_lock_setup_common handler instead of
duplicating this check in two places. This also fixes a minor wart in
the code where we continue referring to the struct flock after
converting it to struct file_lock.

Signed-off-by: Jeff Layton <jlayton@redhat.com>
---
 fs/locks.c | 46 ++++++++++++----------------------------------
 1 file changed, 12 insertions(+), 34 deletions(-)

diff --git a/fs/locks.c b/fs/locks.c
index a5848ed..f96c455 100644
--- a/fs/locks.c
+++ b/fs/locks.c
@@ -354,6 +354,18 @@ flock_to_posix_lock_common(struct file_lock *fl, struct file *filp, short type)
 	fl->fl_ops = NULL;
 	fl->fl_lmops = NULL;
 
+	/* Ensure that fl->fl_filp has compatible f_mode */
+	switch (type) {
+	case F_RDLCK:
+		if (!(filp->f_mode & FMODE_READ))
+			return -EBADF;
+		break;
+	case F_WRLCK:
+		if (!(filp->f_mode & FMODE_WRITE))
+			return -EBADF;
+		break;
+	}
+
 	return assign_type(fl, type);
 }
 
@@ -2060,23 +2072,6 @@ again:
 		file_lock->fl_flags |= FL_SLEEP;
 	}
 	
-	error = -EBADF;
-	switch (flock.l_type) {
-	case F_RDLCK:
-		if (!(filp->f_mode & FMODE_READ))
-			goto out;
-		break;
-	case F_WRLCK:
-		if (!(filp->f_mode & FMODE_WRITE))
-			goto out;
-		break;
-	case F_UNLCK:
-		break;
-	default:
-		error = -EINVAL;
-		goto out;
-	}
-
 	error = do_lock_file_wait(filp, cmd, file_lock);
 
 	/*
@@ -2178,23 +2173,6 @@ again:
 		file_lock->fl_flags |= FL_SLEEP;
 	}
 	
-	error = -EBADF;
-	switch (flock.l_type) {
-	case F_RDLCK:
-		if (!(filp->f_mode & FMODE_READ))
-			goto out;
-		break;
-	case F_WRLCK:
-		if (!(filp->f_mode & FMODE_WRITE))
-			goto out;
-		break;
-	case F_UNLCK:
-		break;
-	default:
-		error = -EINVAL;
-		goto out;
-	}
-
 	error = do_lock_file_wait(filp, cmd, file_lock);
 
 	/*
-- 
1.8.4.2