From 951880e634a79884236a575b896abf55c39ae0bf Mon Sep 17 00:00:00 2001 From: Linus Torvalds Date: Tue, 17 Jan 2012 10:19:41 -0800 Subject: [PATCH] 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 Acked-by: Eric Paris Signed-off-by: Linus Torvalds --- kernel/capability.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/kernel/capability.c b/kernel/capability.c index 0fcf1c14a297..3f1adb6c6470 100644 --- a/kernel/capability.c +++ b/kernel/capability.c @@ -384,7 +384,7 @@ bool ns_capable(struct user_namespace *ns, int cap) BUG(); } - if (has_ns_capability(current, ns, cap)) { + if (security_capable(current_cred(), ns, cap) == 0) { current->flags |= PF_SUPERPRIV; return true; } -- 2.20.1