[RFC][PATCH v4 34/69] atomic_open(): lift the call of may_open() into do_last()

Al Viro
2020-03-13T23:56:45Z

there we'll be able to merge it with its counterparts in other
cases, and there's no reason to do it before the parent has
been unlocked

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
---
fs/namei.c | 26 +++++++++++---------------
1 file changed, 11 insertions(+), 15 deletions(-)

diff --git a/fs/namei.c b/fs/namei.c
index 88f985aff4f8..7e932d9a71a9 100644
--- a/fs/namei.c
+++ b/fs/namei.c
@@ -2949,23 +2949,12 @@ static struct dentry *atomic_open(struct nameidata *nd, struct dentry *dentry,
d_lookup_done(dentry);
if (!error) {
if (file->f_mode & FMODE_OPENED) {
- int acc_mode = op->acc_mode;
if (unlikely(dentry != file->f_path.dentry)) {
dput(dentry);
dentry = dget(file->f_path.dentry);
}
- /*
- * We didn't have the inode before the open, so check open
- * permission here.
- */
- if (file->f_mode & FMODE_CREATED) {
- WARN_ON(!(open_flag & O_CREAT));
+ if (file->f_mode & FMODE_CREATED)
fsnotify_create(dir, dentry);
- acc_mode = 0;
- }
- error = may_open(&file->f_path, acc_mode, open_flag);
- if (WARN_ON(error > 0))
- error = -EINVAL;
} else if (WARN_ON(file->f_path.dentry == DENTRY_NOT_SET)) {
error = -EIO;
} else {
@@ -3208,12 +3197,19 @@ static const char *do_last(struct nameidata *nd,
}

if (file->f_mode & FMODE_OPENED) {
- if ((file->f_mode & FMODE_CREATED) ||
- !S_ISREG(file_inode(file)->i_mode))
+ if (file->f_mode & FMODE_CREATED) {
+ open_flag &= ~O_TRUNC;
+ will_truncate = false;
+ acc_mode = 0;
+ } else if (!S_ISREG(file_inode(file)->i_mode))
will_truncate = false;

audit_inode(nd->name, file->f_path.dentry, 0);
- dput(dentry);
+ dput(nd->path.dentry);
+ nd->path.dentry = dentry;
+ error = may_open(&nd->path, acc_mode, open_flag);
+ if (error)
+ goto out;
goto opened;
}

--
2.11.0