diff options
| author | Serge E. Hallyn <serge@hallyn.com> | 2011-03-23 16:43:25 -0700 |
|---|---|---|
| committer | Linus Torvalds <torvalds@linux-foundation.org> | 2011-03-23 19:47:08 -0700 |
| commit | e795b71799ff0b27365020c9ddaa25d0d83f99c8 (patch) | |
| tree | f3b628c2366f181380a8fbcd490910eb086a7b8e /fs/inode.c | |
| parent | b0e77598f87107001a00b8a4ece9c95e4254ccc4 (diff) | |
userns: userns: check user namespace for task->file uid equivalence checks
Cheat for now and say all files belong to init_user_ns. Next step will be
to let superblocks belong to a user_ns, and derive inode_userns(inode)
from inode->i_sb->s_user_ns. Finally we'll introduce more flexible
arrangements.
Changelog:
Feb 15: make is_owner_or_cap take const struct inode
Feb 23: make is_owner_or_cap bool
[akpm@linux-foundation.org: coding-style fixes]
Signed-off-by: Serge E. Hallyn <serge.hallyn@canonical.com>
Acked-by: "Eric W. Biederman" <ebiederm@xmission.com>
Acked-by: Daniel Lezcano <daniel.lezcano@free.fr>
Acked-by: David Howells <dhowells@redhat.com>
Cc: James Morris <jmorris@namei.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Diffstat (limited to 'fs/inode.c')
| -rw-r--r-- | fs/inode.c | 17 |
1 files changed, 17 insertions, 0 deletions
diff --git a/fs/inode.c b/fs/inode.c index 16fefd373fc..a21d5a938a1 100644 --- a/fs/inode.c +++ b/fs/inode.c @@ -25,6 +25,7 @@ #include <linux/async.h> #include <linux/posix_acl.h> #include <linux/ima.h> +#include <linux/cred.h> /* * This is needed for the following functions: @@ -1733,3 +1734,19 @@ void inode_init_owner(struct inode *inode, const struct inode *dir, inode->i_mode = mode; } EXPORT_SYMBOL(inode_init_owner); + +/* + * return true if current either has CAP_FOWNER to the + * file, or owns the file. + */ +bool is_owner_or_cap(const struct inode *inode) +{ + struct user_namespace *ns = inode_userns(inode); + + if (current_user_ns() == ns && current_fsuid() == inode->i_uid) + return true; + if (ns_capable(ns, CAP_FOWNER)) + return true; + return false; +} +EXPORT_SYMBOL(is_owner_or_cap); |