Merge branch 'misc.namei' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs
Pull namei updates from Al Viro:
"Clearing fallout from mkdirat in io_uring series. The fix in the
kern_path_locked() patch plus associated cleanups"
* 'misc.namei' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs:
putname(): IS_ERR_OR_NULL() is wrong here
namei: Standardize callers of filename_create()
namei: Standardize callers of filename_lookup()
rename __filename_parentat() to filename_parentat()
namei: Fix use after free in kern_path_locked
diff --git a/fs/fs_parser.c b/fs/fs_parser.c
index 980d44fd..3df07c0 100644
--- a/fs/fs_parser.c
+++ b/fs/fs_parser.c
@@ -165,7 +165,6 @@
return invalf(fc, "%s: not usable as path", param->key);
}
- f->refcnt++; /* filename_lookup() drops our ref. */
ret = filename_lookup(param->dirfd, f, flags, _path, NULL);
if (ret < 0) {
errorf(fc, "%s: Lookup failure for '%s'", param->key, f->name);
diff --git a/fs/namei.c b/fs/namei.c
index 95a881e..1946d96 100644
--- a/fs/namei.c
+++ b/fs/namei.c
@@ -255,7 +255,7 @@
void putname(struct filename *name)
{
- if (IS_ERR_OR_NULL(name))
+ if (IS_ERR(name))
return;
BUG_ON(name->refcnt <= 0);
@@ -2467,7 +2467,7 @@
return err;
}
-static int __filename_lookup(int dfd, struct filename *name, unsigned flags,
+int filename_lookup(int dfd, struct filename *name, unsigned flags,
struct path *path, struct path *root)
{
int retval;
@@ -2488,15 +2488,6 @@
return retval;
}
-int filename_lookup(int dfd, struct filename *name, unsigned flags,
- struct path *path, struct path *root)
-{
- int retval = __filename_lookup(dfd, name, flags, path, root);
-
- putname(name);
- return retval;
-}
-
/* Returns 0 and nd will be valid on success; Retuns error, otherwise. */
static int path_parentat(struct nameidata *nd, unsigned flags,
struct path *parent)
@@ -2514,9 +2505,10 @@
return err;
}
-static int __filename_parentat(int dfd, struct filename *name,
- unsigned int flags, struct path *parent,
- struct qstr *last, int *type)
+/* Note: this does not consume "name" */
+static int filename_parentat(int dfd, struct filename *name,
+ unsigned int flags, struct path *parent,
+ struct qstr *last, int *type)
{
int retval;
struct nameidata nd;
@@ -2538,25 +2530,14 @@
return retval;
}
-static int filename_parentat(int dfd, struct filename *name,
- unsigned int flags, struct path *parent,
- struct qstr *last, int *type)
-{
- int retval = __filename_parentat(dfd, name, flags, parent, last, type);
-
- putname(name);
- return retval;
-}
-
/* does lookup, returns the object with parent locked */
-struct dentry *kern_path_locked(const char *name, struct path *path)
+static struct dentry *__kern_path_locked(struct filename *name, struct path *path)
{
struct dentry *d;
struct qstr last;
int type, error;
- error = filename_parentat(AT_FDCWD, getname_kernel(name), 0, path,
- &last, &type);
+ error = filename_parentat(AT_FDCWD, name, 0, path, &last, &type);
if (error)
return ERR_PTR(error);
if (unlikely(type != LAST_NORM)) {
@@ -2572,10 +2553,23 @@
return d;
}
+struct dentry *kern_path_locked(const char *name, struct path *path)
+{
+ struct filename *filename = getname_kernel(name);
+ struct dentry *res = __kern_path_locked(filename, path);
+
+ putname(filename);
+ return res;
+}
+
int kern_path(const char *name, unsigned int flags, struct path *path)
{
- return filename_lookup(AT_FDCWD, getname_kernel(name),
- flags, path, NULL);
+ struct filename *filename = getname_kernel(name);
+ int ret = filename_lookup(AT_FDCWD, filename, flags, path, NULL);
+
+ putname(filename);
+ return ret;
+
}
EXPORT_SYMBOL(kern_path);
@@ -2591,10 +2585,15 @@
const char *name, unsigned int flags,
struct path *path)
{
+ struct filename *filename;
struct path root = {.mnt = mnt, .dentry = dentry};
+ int ret;
+
+ filename = getname_kernel(name);
/* the first argument of filename_lookup() is ignored with root */
- return filename_lookup(AT_FDCWD, getname_kernel(name),
- flags , path, &root);
+ ret = filename_lookup(AT_FDCWD, filename, flags, path, &root);
+ putname(filename);
+ return ret;
}
EXPORT_SYMBOL(vfs_path_lookup);
@@ -2798,8 +2797,11 @@
int user_path_at_empty(int dfd, const char __user *name, unsigned flags,
struct path *path, int *empty)
{
- return filename_lookup(dfd, getname_flags(name, flags, empty),
- flags, path, NULL);
+ struct filename *filename = getname_flags(name, flags, empty);
+ int ret = filename_lookup(dfd, filename, flags, path, NULL);
+
+ putname(filename);
+ return ret;
}
EXPORT_SYMBOL(user_path_at_empty);
@@ -3618,8 +3620,8 @@
return file;
}
-static struct dentry *__filename_create(int dfd, struct filename *name,
- struct path *path, unsigned int lookup_flags)
+static struct dentry *filename_create(int dfd, struct filename *name,
+ struct path *path, unsigned int lookup_flags)
{
struct dentry *dentry = ERR_PTR(-EEXIST);
struct qstr last;
@@ -3634,7 +3636,7 @@
*/
lookup_flags &= LOOKUP_REVAL;
- error = __filename_parentat(dfd, name, lookup_flags, path, &last, &type);
+ error = filename_parentat(dfd, name, lookup_flags, path, &last, &type);
if (error)
return ERR_PTR(error);
@@ -3687,20 +3689,14 @@
return dentry;
}
-static inline struct dentry *filename_create(int dfd, struct filename *name,
- struct path *path, unsigned int lookup_flags)
-{
- struct dentry *res = __filename_create(dfd, name, path, lookup_flags);
-
- putname(name);
- return res;
-}
-
struct dentry *kern_path_create(int dfd, const char *pathname,
struct path *path, unsigned int lookup_flags)
{
- return filename_create(dfd, getname_kernel(pathname),
- path, lookup_flags);
+ struct filename *filename = getname_kernel(pathname);
+ struct dentry *res = filename_create(dfd, filename, path, lookup_flags);
+
+ putname(filename);
+ return res;
}
EXPORT_SYMBOL(kern_path_create);
@@ -3716,7 +3712,11 @@
inline struct dentry *user_path_create(int dfd, const char __user *pathname,
struct path *path, unsigned int lookup_flags)
{
- return filename_create(dfd, getname(pathname), path, lookup_flags);
+ struct filename *filename = getname(pathname);
+ struct dentry *res = filename_create(dfd, filename, path, lookup_flags);
+
+ putname(filename);
+ return res;
}
EXPORT_SYMBOL(user_path_create);
@@ -3797,7 +3797,7 @@
if (error)
goto out1;
retry:
- dentry = __filename_create(dfd, name, &path, lookup_flags);
+ dentry = filename_create(dfd, name, &path, lookup_flags);
error = PTR_ERR(dentry);
if (IS_ERR(dentry))
goto out1;
@@ -3897,7 +3897,7 @@
unsigned int lookup_flags = LOOKUP_DIRECTORY;
retry:
- dentry = __filename_create(dfd, name, &path, lookup_flags);
+ dentry = filename_create(dfd, name, &path, lookup_flags);
error = PTR_ERR(dentry);
if (IS_ERR(dentry))
goto out_putname;
@@ -3996,7 +3996,7 @@
int type;
unsigned int lookup_flags = 0;
retry:
- error = __filename_parentat(dfd, name, lookup_flags, &path, &last, &type);
+ error = filename_parentat(dfd, name, lookup_flags, &path, &last, &type);
if (error)
goto exit1;
@@ -4137,7 +4137,7 @@
struct inode *delegated_inode = NULL;
unsigned int lookup_flags = 0;
retry:
- error = __filename_parentat(dfd, name, lookup_flags, &path, &last, &type);
+ error = filename_parentat(dfd, name, lookup_flags, &path, &last, &type);
if (error)
goto exit1;
@@ -4266,7 +4266,7 @@
goto out_putnames;
}
retry:
- dentry = __filename_create(newdfd, to, &path, lookup_flags);
+ dentry = filename_create(newdfd, to, &path, lookup_flags);
error = PTR_ERR(dentry);
if (IS_ERR(dentry))
goto out_putnames;
@@ -4426,11 +4426,11 @@
if (flags & AT_SYMLINK_FOLLOW)
how |= LOOKUP_FOLLOW;
retry:
- error = __filename_lookup(olddfd, old, how, &old_path, NULL);
+ error = filename_lookup(olddfd, old, how, &old_path, NULL);
if (error)
goto out_putnames;
- new_dentry = __filename_create(newdfd, new, &new_path,
+ new_dentry = filename_create(newdfd, new, &new_path,
(how & LOOKUP_REVAL));
error = PTR_ERR(new_dentry);
if (IS_ERR(new_dentry))
@@ -4689,13 +4689,13 @@
target_flags = 0;
retry:
- error = __filename_parentat(olddfd, from, lookup_flags, &old_path,
- &old_last, &old_type);
+ error = filename_parentat(olddfd, from, lookup_flags, &old_path,
+ &old_last, &old_type);
if (error)
goto put_names;
- error = __filename_parentat(newdfd, to, lookup_flags, &new_path, &new_last,
- &new_type);
+ error = filename_parentat(newdfd, to, lookup_flags, &new_path, &new_last,
+ &new_type);
if (error)
goto exit1;
