From 39f60c1ccee72caa0104145b5dbf5d37cce1ea39 Mon Sep 17 00:00:00 2001 From: Christian Brauner Date: Fri, 13 Jan 2023 12:49:23 +0100 Subject: fs: port xattr to mnt_idmap Convert to struct mnt_idmap. Last cycle we merged the necessary infrastructure in 256c8aed2b42 ("fs: introduce dedicated idmap type for mounts"). This is just the conversion to struct mnt_idmap. Currently we still pass around the plain namespace that was attached to a mount. This is in general pretty convenient but it makes it easy to conflate namespaces that are relevant on the filesystem with namespaces that are relevent on the mount level. Especially for non-vfs developers without detailed knowledge in this area this can be a potential source for bugs. Once the conversion to struct mnt_idmap is done all helpers down to the really low-level helpers will take a struct mnt_idmap argument instead of two namespace arguments. This way it becomes impossible to conflate the two eliminating the possibility of any bugs. All of the vfs and all filesystems only operate on struct mnt_idmap. Acked-by: Dave Chinner Reviewed-by: Christoph Hellwig Signed-off-by: Christian Brauner (Microsoft) --- fs/xattr.c | 27 ++++++++++++--------------- 1 file changed, 12 insertions(+), 15 deletions(-) (limited to 'fs/xattr.c') diff --git a/fs/xattr.c b/fs/xattr.c index d056d9ac247a..1cc1420eccce 100644 --- a/fs/xattr.c +++ b/fs/xattr.c @@ -185,7 +185,7 @@ xattr_supported_namespace(struct inode *inode, const char *prefix) EXPORT_SYMBOL(xattr_supported_namespace); int -__vfs_setxattr(struct user_namespace *mnt_userns, struct dentry *dentry, +__vfs_setxattr(struct mnt_idmap *idmap, struct dentry *dentry, struct inode *inode, const char *name, const void *value, size_t size, int flags) { @@ -201,7 +201,7 @@ __vfs_setxattr(struct user_namespace *mnt_userns, struct dentry *dentry, return -EOPNOTSUPP; if (size == 0) value = ""; /* empty EA, do not remove */ - return handler->set(handler, mnt_userns, dentry, inode, name, value, + return handler->set(handler, idmap, dentry, inode, name, value, size, flags); } EXPORT_SYMBOL(__vfs_setxattr); @@ -210,7 +210,7 @@ EXPORT_SYMBOL(__vfs_setxattr); * __vfs_setxattr_noperm - perform setxattr operation without performing * permission checks. * - * @mnt_userns: user namespace of the mount the inode was found from + * @idmap: idmap of the mount the inode was found from * @dentry: object to perform setxattr on * @name: xattr name to set * @value: value to set @name to @@ -223,7 +223,7 @@ EXPORT_SYMBOL(__vfs_setxattr); * is executed. It also assumes that the caller will make the appropriate * permission checks. */ -int __vfs_setxattr_noperm(struct user_namespace *mnt_userns, +int __vfs_setxattr_noperm(struct mnt_idmap *idmap, struct dentry *dentry, const char *name, const void *value, size_t size, int flags) { @@ -235,7 +235,7 @@ int __vfs_setxattr_noperm(struct user_namespace *mnt_userns, if (issec) inode->i_flags &= ~S_NOSEC; if (inode->i_opflags & IOP_XATTR) { - error = __vfs_setxattr(mnt_userns, dentry, inode, name, value, + error = __vfs_setxattr(idmap, dentry, inode, name, value, size, flags); if (!error) { fsnotify_xattr(dentry); @@ -280,7 +280,6 @@ __vfs_setxattr_locked(struct mnt_idmap *idmap, struct dentry *dentry, const char *name, const void *value, size_t size, int flags, struct inode **delegated_inode) { - struct user_namespace *mnt_userns = mnt_idmap_owner(idmap); struct inode *inode = dentry->d_inode; int error; @@ -288,7 +287,7 @@ __vfs_setxattr_locked(struct mnt_idmap *idmap, struct dentry *dentry, if (error) return error; - error = security_inode_setxattr(mnt_userns, dentry, name, value, size, + error = security_inode_setxattr(idmap, dentry, name, value, size, flags); if (error) goto out; @@ -297,7 +296,7 @@ __vfs_setxattr_locked(struct mnt_idmap *idmap, struct dentry *dentry, if (error) goto out; - error = __vfs_setxattr_noperm(mnt_userns, dentry, name, value, + error = __vfs_setxattr_noperm(idmap, dentry, name, value, size, flags); out: @@ -309,14 +308,13 @@ int vfs_setxattr(struct mnt_idmap *idmap, struct dentry *dentry, const char *name, const void *value, size_t size, int flags) { - struct user_namespace *mnt_userns = mnt_idmap_owner(idmap); struct inode *inode = dentry->d_inode; struct inode *delegated_inode = NULL; const void *orig_value = value; int error; if (size && strcmp(name, XATTR_NAME_CAPS) == 0) { - error = cap_convert_nscap(mnt_userns, dentry, &value, size); + error = cap_convert_nscap(idmap, dentry, &value, size); if (error < 0) return error; size = error; @@ -484,7 +482,7 @@ vfs_listxattr(struct dentry *dentry, char *list, size_t size) EXPORT_SYMBOL_GPL(vfs_listxattr); int -__vfs_removexattr(struct user_namespace *mnt_userns, struct dentry *dentry, +__vfs_removexattr(struct mnt_idmap *idmap, struct dentry *dentry, const char *name) { struct inode *inode = d_inode(dentry); @@ -498,7 +496,7 @@ __vfs_removexattr(struct user_namespace *mnt_userns, struct dentry *dentry, return PTR_ERR(handler); if (!handler->set) return -EOPNOTSUPP; - return handler->set(handler, mnt_userns, dentry, inode, name, NULL, 0, + return handler->set(handler, idmap, dentry, inode, name, NULL, 0, XATTR_REPLACE); } EXPORT_SYMBOL(__vfs_removexattr); @@ -518,7 +516,6 @@ __vfs_removexattr_locked(struct mnt_idmap *idmap, struct dentry *dentry, const char *name, struct inode **delegated_inode) { - struct user_namespace *mnt_userns = mnt_idmap_owner(idmap); struct inode *inode = dentry->d_inode; int error; @@ -526,7 +523,7 @@ __vfs_removexattr_locked(struct mnt_idmap *idmap, if (error) return error; - error = security_inode_removexattr(mnt_userns, dentry, name); + error = security_inode_removexattr(idmap, dentry, name); if (error) goto out; @@ -534,7 +531,7 @@ __vfs_removexattr_locked(struct mnt_idmap *idmap, if (error) goto out; - error = __vfs_removexattr(mnt_userns, dentry, name); + error = __vfs_removexattr(idmap, dentry, name); if (!error) { fsnotify_xattr(dentry); -- cgit v1.2.3