Revert "capabitlies: ns_capable can use the cap helpers rather than lsm call"
This reverts commit d2a7009f0bb03fa22ad08dd25472efa0568126b9.
J. R. Okajima explains:
"After this commit, I am afraid access(2) on NFS may not work
correctly. The scenario based upon my guess.
- access(2) overrides the credentials.
- calls inode_permission() -- ... -- generic_permission() --
ns_capable().
- while the old ns_capable() calls security_capable(current_cred()),
the new ns_capable() calls has_ns_capability(current) --
security_capable(__task_cred(t)).
current_cred() returns current->cred which is effective (overridden)
credentials, but __task_cred(current) returns current->real_cred (the
NFSD's credential). And the overridden credentials by access(2) lost."
Requested-by: J. R. Okajima <hooanon05@yahoo.co.jp>
Acked-by: Eric Paris <eparis@redhat.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
diff --git a/kernel/capability.c b/kernel/capability.c
index 0fcf1c1..3f1adb6 100644
--- a/kernel/capability.c
+++ b/kernel/capability.c
@@ -384,7 +384,7 @@
BUG();
}
- if (has_ns_capability(current, ns, cap)) {
+ if (security_capable(current_cred(), ns, cap) == 0) {
current->flags |= PF_SUPERPRIV;
return true;
}