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| author | Christian Brauner <christian.brauner@ubuntu.com> | 2021-01-21 14:19:24 +0100 |
|---|---|---|
| committer | Christian Brauner <christian.brauner@ubuntu.com> | 2021-01-24 14:27:16 +0100 |
| commit | 47291baa8ddfdae10663624ff0a15ab165952708 (patch) | |
| tree | 132a9486b82c5eada1c4b375f693522f0a04d629 /fs/libfs.c | |
| parent | 0558c1bf5a0811bf5e3753eed911a15b9bd08271 (diff) | |
| download | linux-47291baa8ddfdae10663624ff0a15ab165952708.tar.gz linux-47291baa8ddfdae10663624ff0a15ab165952708.tar.bz2 linux-47291baa8ddfdae10663624ff0a15ab165952708.zip | |
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 <hch@lst.de>
Cc: David Howells <dhowells@redhat.com>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: linux-fsdevel@vger.kernel.org
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: James Morris <jamorris@linux.microsoft.com>
Acked-by: Serge Hallyn <serge@hallyn.com>
Signed-off-by: Christian Brauner <christian.brauner@ubuntu.com>
Diffstat (limited to 'fs/libfs.c')
| -rw-r--r-- | fs/libfs.c | 7 |
1 files changed, 6 insertions, 1 deletions
diff --git a/fs/libfs.c b/fs/libfs.c index d1c3bade9f30..f8b3c02b4f0f 100644 --- a/fs/libfs.c +++ b/fs/libfs.c @@ -1318,9 +1318,14 @@ 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 = generic_permission, + .permission = empty_dir_permission, .setattr = empty_dir_setattr, .getattr = empty_dir_getattr, .listxattr = empty_dir_listxattr, |