From 549c7297717c32ee53f156cd949e055e601f67bb Mon Sep 17 00:00:00 2001 From: Christian Brauner Date: Thu, 21 Jan 2021 14:19:43 +0100 Subject: fs: make helpers idmap mount aware Extend some inode methods with an additional user namespace argument. A filesystem that is aware of idmapped mounts will receive the user namespace the mount has been marked with. This can be used for additional permission checking and also to enable filesystems to translate between uids and gids if they need to. We have implemented all relevant helpers in earlier patches. As requested we simply extend the exisiting inode method instead of introducing new ones. This is a little more code churn but it's mostly mechanical and doesnt't leave us with additional inode methods. Link: https://lore.kernel.org/r/20210121131959.646623-25-christian.brauner@ubuntu.com Cc: Christoph Hellwig Cc: David Howells Cc: Al Viro Cc: linux-fsdevel@vger.kernel.org Reviewed-by: Christoph Hellwig Signed-off-by: Christian Brauner --- fs/libfs.c | 31 +++++++++++++++---------------- 1 file changed, 15 insertions(+), 16 deletions(-) (limited to 'fs/libfs.c') diff --git a/fs/libfs.c b/fs/libfs.c index 508e9ea8e6f3..967aefda6ee3 100644 --- a/fs/libfs.c +++ b/fs/libfs.c @@ -27,8 +27,9 @@ #include "internal.h" -int simple_getattr(const struct path *path, struct kstat *stat, - u32 request_mask, unsigned int query_flags) +int simple_getattr(struct user_namespace *mnt_userns, const struct path *path, + struct kstat *stat, u32 request_mask, + unsigned int query_flags) { struct inode *inode = d_inode(path->dentry); generic_fillattr(&init_user_ns, inode, stat); @@ -447,9 +448,9 @@ int simple_rmdir(struct inode *dir, struct dentry *dentry) } EXPORT_SYMBOL(simple_rmdir); -int simple_rename(struct inode *old_dir, struct dentry *old_dentry, - struct inode *new_dir, struct dentry *new_dentry, - unsigned int flags) +int simple_rename(struct user_namespace *mnt_userns, struct inode *old_dir, + struct dentry *old_dentry, struct inode *new_dir, + struct dentry *new_dentry, unsigned int flags) { struct inode *inode = d_inode(old_dentry); int they_are_dirs = d_is_dir(old_dentry); @@ -492,18 +493,19 @@ EXPORT_SYMBOL(simple_rename); * on simple regular filesystems. Anything that needs to change on-disk * or wire state on size changes needs its own setattr method. */ -int simple_setattr(struct dentry *dentry, struct iattr *iattr) +int simple_setattr(struct user_namespace *mnt_userns, struct dentry *dentry, + struct iattr *iattr) { struct inode *inode = d_inode(dentry); int error; - error = setattr_prepare(&init_user_ns, dentry, iattr); + error = setattr_prepare(mnt_userns, dentry, iattr); if (error) return error; if (iattr->ia_valid & ATTR_SIZE) truncate_setsize(inode, iattr->ia_size); - setattr_copy(&init_user_ns, inode, iattr); + setattr_copy(mnt_userns, inode, iattr); mark_inode_dirty(inode); return 0; } @@ -1300,7 +1302,8 @@ static struct dentry *empty_dir_lookup(struct inode *dir, struct dentry *dentry, return ERR_PTR(-ENOENT); } -static int empty_dir_getattr(const struct path *path, struct kstat *stat, +static int empty_dir_getattr(struct user_namespace *mnt_userns, + const struct path *path, struct kstat *stat, u32 request_mask, unsigned int query_flags) { struct inode *inode = d_inode(path->dentry); @@ -1308,7 +1311,8 @@ static int empty_dir_getattr(const struct path *path, struct kstat *stat, return 0; } -static int empty_dir_setattr(struct dentry *dentry, struct iattr *attr) +static int empty_dir_setattr(struct user_namespace *mnt_userns, + struct dentry *dentry, struct iattr *attr) { return -EPERM; } @@ -1318,14 +1322,9 @@ static ssize_t empty_dir_listxattr(struct dentry *dentry, char *list, size_t siz return -EOPNOTSUPP; } -static int empty_dir_permission(struct inode *inode, int mask) -{ - return generic_permission(&init_user_ns, inode, mask); -} - static const struct inode_operations empty_dir_inode_operations = { .lookup = empty_dir_lookup, - .permission = empty_dir_permission, + .permission = generic_permission, .setattr = empty_dir_setattr, .getattr = empty_dir_getattr, .listxattr = empty_dir_listxattr, -- cgit