From mboxrd@z Thu Jan 1 00:00:00 1970 Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.remote-ip=100.103.45.18 ARC-Seal: i=1; d=subspace.kernel.org; s=arc20261015; a=rsa-sha256; cv=none; t=1792887144; b=Y1jFZHEZ8IWIamkfrh3Tt0lyiePUcw/gbQk4KAxBS4r6KcNGrOMxg5BNvkoBuAzobdaL pDwhcLsHUXjQnoIqL/EfLIsn3MNnMbR2Pe6bLhndjB37OwnhX1jWLUZ73pJmAY16ci1N6 cQr4bOpPGPD289Gbcqc9JFHI5Kjk2cE6XTuh2c5IdXanpvlURsZoda0C16DEoEQFRP+MX GE5Zs1ypn0uctVTizlgEJyAouu7FL9AoZlb9vB08bQsMSAPl1vG0SiRDXr36JXR3NbOZr 28B1B0c43G42PlcnG0g5AATdU9XtUcPZR/iCmP9Gw4/vw8sGk3nslcgskvXnLrltkVQ== ARC-Message-Signature: i=1; d=subspace.kernel.org; s=arc20261015; a=rsa-sha256; c=relaxed/relaxed; t=1792887144; h=Received:DKIM-Signature:From:To:Cc:Subject:Date:Message-ID:X-Mailer: In-Reply-To:References:MIME-Version:Content-Transfer-Encoding; bh=d0/08Y7FCHEGVevGTNjTfPTBox7sBeP1ImWEFHXBc7U=; b=N+dx5JCyQpKpdb+ASC0u0DSSae51+AvxjSWgg0DwKeCerOTY2JGJrPkc3rxf+32DhmCr LfZL2w4G+rghi/DLKzAmDJ6SJhJWWVkEzEBfhB4J5zGpVG/excojA7KPRAGO6sGSPZPZR sQY3CJecCRpKSTF/AI3mQ0OKEZWUWBa07lLqdp1t9Xes81fVdNu5IAXvgRAyds+/ofnY7 GnUXlgalt+CFhETdHbB98owjUdrMeewyB7lCSEP5yGTxsYcOiQY+xBFSEjbTWX+VbJUSS 8JUGuP3cxQhuBS+yXp/81eADl7RnvEZWuTZEOYyazwBJej2AzFWQYnlCpIPSAFAprHg== ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dkim=pass header.d=kernel.org header.i=@kernel.org header.a=rsa-sha256 header.s=k20260515 header.b=WN4Hv2Iq; arc=none smtp.remote-ip=100.103.45.18 Received: from smtp.kernel.org (quasi.space.kernel.org [100.103.45.18]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature ECDSA (prime256v1)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with UTF8SMTPS id 0ABC4606A31A; Sun, 25 Oct 2026 00:12:24 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key, unprotected) header.d=kernel.org header.i=@kernel.org header.a=rsa-sha256 header.s=k20260515 header.b=WN4Hv2Iq Received: by smtp.kernel.org (Postfix) with UTF8SMTPSA id 33C6F1F01825; Sun, 25 Oct 2026 00:12:23 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=kernel.org; s=k20260515; t=1792887143; bh=d0/08Y7FCHEGVevGTNjTfPTBox7sBeP1ImWEFHXBc7U=; h=From:To:Cc:Subject:Date:In-Reply-To:References; b=WN4Hv2IqQWLVRP/M4vAiyAP5X3mm8J5IoQ2L1ebzSJC7Dl93iyjjKp8RDsjnL4SfI uTa3vB52skHgrJf+3C21jON6CVuJSSF65O9+D8Awt3RhVlfB44q1YPdXk5+l9YxSZ8 xcAKoY46pCgH6u5EM1/bRZOxT6swuFe++psPWLIgBafboJtLWQVNB8yn8ycHljFVwR VA9jow8jDmAHT69hWz2+4G80yO1m/Vm/XCutHlD5JNVPmw7y/qKSrB1S+WRVtrxwuq ZfEsu4cyM4LbH0mwOWXKDdSoMEOPC68q+Gesd8EcIF8oQqwGCQyODUAeOQJ0IIzgsJ t70zM+F6cZ4VA== From: Jarkko Sakkinen To: David Howells Cc: keyrings@vger.kernel.org, Linus Torvalds , Eric Biggers , Jarkko Sakkinen , Alasdair Kergon , Mike Snitzer , Mikulas Patocka , Benjamin Marzinski , "Theodore Y. Ts'o" , Thomas Graf , Herbert Xu , Andrew Morton , Paul Moore , James Morris , "Serge E. Hallyn" , Shuah Khan , Christian Brauner , dm-devel@lists.linux.dev (open list:DEVICE-MAPPER (LVM)), linux-kernel@vger.kernel.org (open list), fsverity@lists.linux.dev (open list:FSVERITY: READ-ONLY FILE-BASED AUTHENTICITY PRO...), linux-crypto@vger.kernel.org (open list:RHASHTABLE), linux-security-module@vger.kernel.org (open list:SECURITY SUBSYSTEM), linux-kselftest@vger.kernel.org (open list:KERNEL SELFTEST FRAMEWORK) Subject: [PATCH v3 4/6] KEYS: Introduce keyring_is_empty() Date: Sun, 25 Oct 2026 03:10:12 +0300 Message-ID: <20261025001105.1824178-5-jarkko@kernel.org> X-Mailer: git-send-email 2.47.3 In-Reply-To: <20261025001105.1824178-1-jarkko@kernel.org> References: <20261025001105.1824178-1-jarkko@kernel.org> X-Mailing-List: linux-security-module@vger.kernel.org List-Id: List-Post: List-Help: List-Subscribe: List-Unsubscribe: List-Owner: Precedence: list MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Introduce keyring_is_empty() in order to decouple for dm-verity and fs-verity how keyring internally manages the keys. Signed-off-by: Jarkko Sakkinen --- drivers/md/dm-verity-verify-sig.c | 2 +- fs/verity/signature.c | 2 +- include/linux/key.h | 1 + security/keys/keyring.c | 10 ++++++++++ .../selftests/dm-verity/test-dm-verity-keyring.sh | 2 +- 5 files changed, 14 insertions(+), 3 deletions(-) diff --git a/drivers/md/dm-verity-verify-sig.c b/drivers/md/dm-verity-verify-sig.c index b2b55c41e2cb..2ccb71bfb3ca 100644 --- a/drivers/md/dm-verity-verify-sig.c +++ b/drivers/md/dm-verity-verify-sig.c @@ -153,7 +153,7 @@ int verity_verify_root_hash(const void *root_hash, size_t root_hash_len, if (ret != -ENOKEY && ret != -EKEYREJECTED) return ret; - if (dm_verity_keyring->keys.nr_leaves_on_tree && + if (!keyring_is_empty(dm_verity_keyring) && dm_verity_keyring->restrict_link) ret = verify_pkcs7_signature(root_hash, root_hash_len, sig_data, sig_len, diff --git a/fs/verity/signature.c b/fs/verity/signature.c index 0302a4e506ec..890d33b9d812 100644 --- a/fs/verity/signature.c +++ b/fs/verity/signature.c @@ -67,7 +67,7 @@ int fsverity_verify_signature(const struct fsverity_info *vi, return 0; } - if (fsverity_keyring->keys.nr_leaves_on_tree == 0) { + if (keyring_is_empty(fsverity_keyring)) { /* * The ".fs-verity" keyring is empty, due to builtin signatures * being supported by the kernel but not actually being used. diff --git a/include/linux/key.h b/include/linux/key.h index 3b8af14fb323..df2034fc5436 100644 --- a/include/linux/key.h +++ b/include/linux/key.h @@ -439,6 +439,7 @@ extern int restrict_link_reject(struct key *keyring, struct key *restriction_key); extern int keyring_clear(struct key *keyring); +bool keyring_is_empty(const struct key *keyring); extern key_ref_t keyring_search(key_ref_t keyring, struct key_type *type, diff --git a/security/keys/keyring.c b/security/keys/keyring.c index 5281da9d5bf7..4642754db6bf 100644 --- a/security/keys/keyring.c +++ b/security/keys/keyring.c @@ -443,6 +443,16 @@ static void keyring_destroy(struct key *keyring) assoc_array_destroy(&keyring->keys, &keyring_assoc_array_ops); } +/** + * keyring_is_empty - Check whether a keyring contains any links + * @keyring: The keyring to check. + */ +bool keyring_is_empty(const struct key *keyring) +{ + return READ_ONCE(keyring->keys.nr_leaves_on_tree) == 0; +} +EXPORT_SYMBOL(keyring_is_empty); + /* * Describe a keyring for /proc. */ diff --git a/tools/testing/selftests/dm-verity/test-dm-verity-keyring.sh b/tools/testing/selftests/dm-verity/test-dm-verity-keyring.sh index 1f9601ef22f8..792449d356cf 100755 --- a/tools/testing/selftests/dm-verity/test-dm-verity-keyring.sh +++ b/tools/testing/selftests/dm-verity/test-dm-verity-keyring.sh @@ -746,7 +746,7 @@ test_keyring_inactive_when_empty() { log_info "TEST: Verify dm-verity keyring is inactive when sealed empty" # When keyring_unsealed=0, the keyring is sealed immediately while empty - # This means it should NOT be used for verification (nr_leaves_on_tree=0) + # An empty keyring should NOT be used for verification. log_info "Keyring state (should be empty and sealed):" list_keyring_keys -- 2.47.3