From: David Howells Date: Mon, 19 Oct 2015 10:20:28 +0000 (+0100) Subject: KEYS: Don't permit request_key() to construct a new keyring X-Git-Tag: v3.18.89~59 X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=337cde8f541783dbc7fb0f974cd82798ba77794c;p=thirdparty%2Fkernel%2Fstable.git KEYS: Don't permit request_key() to construct a new keyring commit 911b79cde95c7da0ec02f48105358a36636b7a71 upstream. If request_key() is used to find a keyring, only do the search part - don't do the construction part if the keyring was not found by the search. We don't really want keyrings in the negative instantiated state since the rejected/negative instantiation error value in the payload is unioned with keyring metadata. Now the kernel gives an error: request_key("keyring", "#selinux,bdekeyring", "keyring", KEY_SPEC_USER_SESSION_KEYRING) = -1 EPERM (Operation not permitted) Signed-off-by: David Howells Signed-off-by: Eric Biggers Signed-off-by: Greg Kroah-Hartman --- diff --git a/security/keys/request_key.c b/security/keys/request_key.c index 2e6eefda4f50f..3ca46e5e43dc5 100644 --- a/security/keys/request_key.c +++ b/security/keys/request_key.c @@ -467,6 +467,9 @@ static struct key *construct_key_and_link(struct keyring_search_context *ctx, if (ret) goto error; + if (ctx->index_key.type == &key_type_keyring) + return ERR_PTR(-EPERM); + user = key_user_lookup(current_fsuid()); if (!user) { ret = -ENOMEM;