Colin Ian King reported the following
1. create a minix file system and mount it
2. open a file on the file system with O_RDWR | O_CREAT | O_TRUNC | O_DIRECT
3. open fails with -EINVAL but leaves an empty file behind. All other open() failures don't leave the
failed open files behind.
The reason is because when checking the O_DIRECT in do_dentry_open, the inode has created, and later err
processing can't remove the inode:
/* NB: we're sure to have correct a_ops only after f_op->open */
if (f->f_flags & O_DIRECT) {
if (!f->f_mapping->a_ops || !f->f_mapping->a_ops->direct_IO)
return -EINVAL;
}
The patch will check the O_DIRECT before creating the inode in lookup_open function.
Signed-off-by: Qinghua Jin <qhjin_dev@xxxxxxx>
Reported-by: Colin Ian King <colin.king@xxxxxxxxxxxxx>
---
fs/namei.c | 7 +++++++
fs/open.c | 6 ------
2 files changed, 7 insertions(+), 6 deletions(-)
diff --git a/fs/namei.c b/fs/namei.c
index 1f9d2187c765..24c6bcba702d 100644
--- a/fs/namei.c
+++ b/fs/namei.c
@@ -3277,6 +3277,13 @@ static struct dentry *lookup_open(struct nameidata *nd, struct file *file,
goto out_dput;
}
+ if (open_flag & O_DIRECT) {
+ if (!dir_inode->i_mapping || !dir_inode->i_mapping->a_ops ||
+ !dir_inode->i_mapping->a_ops->direct_IO) {
+ error = -EINVAL;
+ goto out_dput;
+ }
+ }
error = dir_inode->i_op->create(mnt_userns, dir_inode, dentry,
mode, open_flag & O_EXCL);
if (error)
diff --git a/fs/open.c b/fs/open.c
index f732fb94600c..2829c3613c0f 100644
--- a/fs/open.c
+++ b/fs/open.c
@@ -838,12 +838,6 @@ static int do_dentry_open(struct file *f,
file_ra_state_init(&f->f_ra, f->f_mapping->host->i_mapping);
- /* NB: we're sure to have correct a_ops only after f_op->open */
- if (f->f_flags & O_DIRECT) {
- if (!f->f_mapping->a_ops || !f->f_mapping->a_ops->direct_IO)
- return -EINVAL;
- }
-
/*
* XXX: Huge page cache doesn't support writing yet. Drop all page
* cache for this file before processing writes.
--
2.30.2
