diff options
| author | Namjae Jeon | 2023-12-31 16:12:37 +0900 |
|---|---|---|
| committer | Greg Kroah-Hartman | 2024-01-05 15:18:29 +0100 |
| commit | 6927ffe7479c72e7ebf885507227266a75f7c97d (patch) | |
| tree | 844007646c22b2fdce3b294e40f62f0983e29155 /include/linux | |
| parent | 6e99fbb4296ad0a2f8c6674246a345045ef1eccb (diff) | |
ksmbd: fix racy issue from using ->d_parent and ->d_name
[ Upstream commit 74d7970febf7e9005375aeda0df821d2edffc9f7 ]
Al pointed out that ksmbd has racy issue from using ->d_parent and ->d_name
in ksmbd_vfs_unlink and smb2_vfs_rename(). and use new lock_rename_child()
to lock stable parent while underlying rename racy.
Introduce vfs_path_parent_lookup helper to avoid out of share access and
export vfs functions like the following ones to use
vfs_path_parent_lookup().
- rename __lookup_hash() to lookup_one_qstr_excl().
- export lookup_one_qstr_excl().
- export getname_kernel() and putname().
vfs_path_parent_lookup() is used for parent lookup of destination file
using absolute pathname given from FILE_RENAME_INFORMATION request.
Signed-off-by: Namjae Jeon <linkinjeon@kernel.org>
Signed-off-by: Steve French <stfrench@microsoft.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
Diffstat (limited to 'include/linux')
| -rw-r--r-- | include/linux/namei.h | 6 |
1 files changed, 6 insertions, 0 deletions
diff --git a/include/linux/namei.h b/include/linux/namei.h index 2b66021c740d..5c0149603dc3 100644 --- a/include/linux/namei.h +++ b/include/linux/namei.h @@ -57,12 +57,18 @@ static inline int user_path_at(int dfd, const char __user *name, unsigned flags, return user_path_at_empty(dfd, name, flags, path, NULL); } +struct dentry *lookup_one_qstr_excl(const struct qstr *name, + struct dentry *base, + unsigned int flags); extern int kern_path(const char *, unsigned, struct path *); extern struct dentry *kern_path_create(int, const char *, struct path *, unsigned int); extern struct dentry *user_path_create(int, const char __user *, struct path *, unsigned int); extern void done_path_create(struct path *, struct dentry *); extern struct dentry *kern_path_locked(const char *, struct path *); +int vfs_path_parent_lookup(struct filename *filename, unsigned int flags, + struct path *parent, struct qstr *last, int *type, + const struct path *root); extern struct dentry *try_lookup_one_len(const char *, struct dentry *, int); extern struct dentry *lookup_one_len(const char *, struct dentry *, int); |