The definition of the function get_empty_filp() has been modified in order
to pass to it the credentials of the subject creating a new file
descriptor.
This function is called by dentry_open() in fs/open.c, do_filp_open() in
fs/namei.c and alloc_file() in fs/file_table.c.
The credentials passed by these functions are not NULL only in the first
case because dentry_open() is the only which explicitly receives them as
parameter.
The 'cred' variable in the function get_empty_filp() is initialized with
the supplied credentials if they are not NULL, the credentials of the
'current' process in the other case.
Signed-off-by: Roberto Sassu <[email protected]>
---
fs/file_table.c | 6 +++---
fs/internal.h | 2 +-
fs/namei.c | 2 +-
fs/open.c | 2 +-
4 files changed, 6 insertions(+), 6 deletions(-)
diff --git a/fs/file_table.c b/fs/file_table.c
index c3dee38..fd446e3 100644
--- a/fs/file_table.c
+++ b/fs/file_table.c
@@ -102,9 +102,9 @@ int proc_nr_files(ctl_table *table, int write,
* done, you will imbalance int the mount's writer count
* and a warning at __fput() time.
*/
-struct file *get_empty_filp(void)
+struct file *get_empty_filp(const struct cred *task_cred)
{
- const struct cred *cred = current_cred();
+ const struct cred *cred = task_cred ? task_cred : current_cred();
static long old_max;
struct file * f;
@@ -171,7 +171,7 @@ struct file *alloc_file(struct path *path, fmode_t mode,
{
struct file *file;
- file = get_empty_filp();
+ file = get_empty_filp(NULL);
if (!file)
return NULL;
diff --git a/fs/internal.h b/fs/internal.h
index e43b9a4..c165615 100644
--- a/fs/internal.h
+++ b/fs/internal.h
@@ -86,7 +86,7 @@ extern void chroot_fs_refs(struct path *, struct path *);
extern void file_sb_list_add(struct file *f, struct super_block *sb);
extern void file_sb_list_del(struct file *f);
extern void mark_files_ro(struct super_block *);
-extern struct file *get_empty_filp(void);
+extern struct file *get_empty_filp(const struct cred *task_cred);
/*
* super.c
diff --git a/fs/namei.c b/fs/namei.c
index 5362af9..c78e1ef 100644
--- a/fs/namei.c
+++ b/fs/namei.c
@@ -1791,7 +1791,7 @@ reval:
*/
error = -ENFILE;
- filp = get_empty_filp();
+ filp = get_empty_filp(NULL);
if (filp == NULL)
goto exit_parent;
nd.intent.open.file = filp;
diff --git a/fs/open.c b/fs/open.c
index 4197b9e..02adb56 100644
--- a/fs/open.c
+++ b/fs/open.c
@@ -819,7 +819,7 @@ struct file *dentry_open(struct dentry *dentry, struct vfsmount *mnt, int flags,
}
error = -ENFILE;
- f = get_empty_filp();
+ f = get_empty_filp(cred);
if (f == NULL) {
dput(dentry);
mntput(mnt);
--
1.7.2.3