From 47291baa8ddfdae10663624ff0a15ab165952708 Mon Sep 17 00:00:00 2001 From: Christian Brauner Date: Thu, 21 Jan 2021 14:19:24 +0100 Subject: namei: make permission helpers idmapped mount aware The two helpers inode_permission() and generic_permission() are used by the vfs to perform basic permission checking by verifying that the caller is privileged over an inode. In order to handle idmapped mounts we extend the two helpers with an additional user namespace argument. On idmapped mounts the two helpers will make sure to map the inode according to the mount's user namespace and then peform identical permission checks to inode_permission() and generic_permission(). If the initial user namespace is passed nothing changes so non-idmapped mounts will see identical behavior as before. Link: https://lore.kernel.org/r/20210121131959.646623-6-christian.brauner@ubuntu.com Cc: Christoph Hellwig Cc: David Howells Cc: Al Viro Cc: linux-fsdevel@vger.kernel.org Reviewed-by: Christoph Hellwig Reviewed-by: James Morris Acked-by: Serge Hallyn Signed-off-by: Christian Brauner --- fs/ocfs2/file.c | 2 +- fs/ocfs2/refcounttree.c | 4 ++-- 2 files changed, 3 insertions(+), 3 deletions(-) (limited to 'fs/ocfs2') diff --git a/fs/ocfs2/file.c b/fs/ocfs2/file.c index 85979e2214b3..0c75619adf54 100644 --- a/fs/ocfs2/file.c +++ b/fs/ocfs2/file.c @@ -1355,7 +1355,7 @@ int ocfs2_permission(struct inode *inode, int mask) dump_stack(); } - ret = generic_permission(inode, mask); + ret = generic_permission(&init_user_ns, inode, mask); ocfs2_inode_unlock_tracker(inode, 0, &oh, had_lock); out: diff --git a/fs/ocfs2/refcounttree.c b/fs/ocfs2/refcounttree.c index 3b397fa9c9e8..c26937824be1 100644 --- a/fs/ocfs2/refcounttree.c +++ b/fs/ocfs2/refcounttree.c @@ -4346,7 +4346,7 @@ static inline int ocfs2_may_create(struct inode *dir, struct dentry *child) return -EEXIST; if (IS_DEADDIR(dir)) return -ENOENT; - return inode_permission(dir, MAY_WRITE | MAY_EXEC); + return inode_permission(&init_user_ns, dir, MAY_WRITE | MAY_EXEC); } /** @@ -4400,7 +4400,7 @@ static int ocfs2_vfs_reflink(struct dentry *old_dentry, struct inode *dir, * file. */ if (!preserve) { - error = inode_permission(inode, MAY_READ); + error = inode_permission(&init_user_ns, inode, MAY_READ); if (error) return error; } -- cgit v1.2.3