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=1794672745; b=bsX16GJPfTc9U0eZgtfq6vveOKdlFyVKP6bQpD+cushvYkcgV53PWwuiuW4vut1QkBT/ OUuP4ioRjlppwrye2lZJ65qZUlKkshbedjqGpJRAsbVf750Hu/ZtPzyn1GyRNAZ2J6KVu K4YNB8oZdRDrSKgd7CD6K7WuPvHuQI1KdkgWWHZ0faTi6pIytU/VrZ7mtARTI+tZ3DDz5 uMzXNZiUFJDYxiLZCFVSZFYz73fNgmTb7ZWhIhSiraPMubXHRYd23Z1+77UvPB39xYH/y TLm5RB+U8RfdwhV/+ahzAdSpGV/Hd6WDrc60rodv+F1prEL0TeGbLHkWna20kkDHHMw== ARC-Message-Signature: i=1; d=subspace.kernel.org; s=arc20261015; a=rsa-sha256; c=relaxed/relaxed; t=1794672745; h=Received:DKIM-Signature:From:To:Cc:Subject:Date:Message-ID:X-Mailer: In-Reply-To:References:MIME-Version:Content-Transfer-Encoding; bh=I0LV/JQpN8yDGYTTWcI8HQY8CmcG+PtzomAV8QbPhzo=; b=yK+XDEgTE+X97lM2NhyZHp+PasfXfCHXW0K8+iaw7SyblWiHhL8t/iLF0PET9rAJUm9n +AFRxkr1N9COJkcPMk1vVkpCEf/TBr8J+alyNavMHK4Hy8UBr4VejK7LEhPfkXCFTArKy GyNMj1YlwITOU0NAX9PJIXIwoaE33ZVpXQ52l+a3FYuySeLXGscEbt7DkKEBAbpw4C5bR /Axbzay3h23kF1c122uE9dJKlFCfE2NDzZCJgSJC1l6Lm57xwwAA8IQUh/TFRbI+Q6VQp lVrYUBsKN62oz1keoQJqxPaXK4Qas4GhdmSk4DrtyNtpXnQ5ky/qmvYBXTs6iz6DNew== 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=cY0hz8bN; 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 EC6B0606A33B; Sat, 14 Nov 2026 16:12:24 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.a=rsa-sha256 header.s=k20260515 header.b=cY0hz8bN Received: by smtp.kernel.org (Postfix) with UTF8SMTPSA id ED1361F000C9; Sat, 14 Nov 2026 16:12:23 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=kernel.org; s=k20260515; t=1794672744; bh=I0LV/JQpN8yDGYTTWcI8HQY8CmcG+PtzomAV8QbPhzo=; h=From:To:Cc:Subject:Date:In-Reply-To:References; b=cY0hz8bNYhXf9O8n4uRhQOzSP6DAXLGTdDeDBam8K8sTTtff5pwce1qXEv0/lYWvl ae5IXyOOZ6yGkighwoKxBhGuCPl64DMW9MxZa2Z2j6uDK7bmnS+0CIDe76B6C7VGgH YV4r3+ekqWPoLPMncwaoY42i8otFlzkPK3r8CxfEF2orckBaKnnJr9xWm7l930mO0V RflBGE250Ach2i9/mdTnZCk79JdqA2ss5JrrYUkIGfvGDH6JtCAAyZ/8q0CDlYvAa9 LXib2QScwUOP/jbQ91Sg/gMGupVi2a5n5A8lwTzwTL5mGP2P3EOaXn3xlmbxdGHMak f+vVnRAtkaFEg== From: Jarkko Sakkinen To: David Howells Cc: Jarkko Sakkinen , bpf@vger.kernel.org, dm-devel@lists.linux.dev, fsverity@lists.linux.dev, keyrings@vger.kernel.org, linux-doc@vger.kernel.org, linux-kernel@vger.kernel.org, linux-kselftest@vger.kernel.org, linux-security-module@vger.kernel.org, Alasdair Kergon , Alexander Gordeev , Alexei Starovoitov , Alex Shi , Anastasia Eskova , Andrew Morton , Andrii Nakryiko , Benjamin Marzinski , Christian Borntraeger , Daniel Borkmann , Dongliang Mu , Eduard Zingerman , Emil Tsalapatis , Eric Biggers , Ignat Korchagin , Heiko Carstens , Ihor Solodrai , James Bottomley , James Morris , Jiri Olsa , Jonathan Corbet , Kumar Kartikeya Dwivedi , Linus Torvalds , Martin KaFai Lau , Mike Snitzer , Mikulas Patocka , Mimi Zohar , Paul Moore , Peter Oberparleiter , Randy Dunlap , Roberto Sassu , "Serge E. Hallyn" , Shuah Khan , Song Liu , Sven Schnelle , "Theodore Y. Ts'o" , Vasily Gorbik , Yanteng Si , Yonghong Song , stable@vger.kernel.org Subject: [PATCH v11 1/6] s390/cert_store: Pin the user session keyring Date: Sat, 14 Nov 2026 18:12:06 +0200 Message-ID: <20261114161211.376859-2-jarkko@kernel.org> X-Mailer: git-send-email 2.47.3 In-Reply-To: <20261114161211.376859-1-jarkko@kernel.org> References: <20261114161211.376859-1-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 The user session keyring stays alive only because the session keyring is pinned by current_cred(). Pin the reference at: 1. find_cs_keyring() 2. cleanup_cs_keys() 3. create_cs_keyring() Cc: David Howells Cc: stable@vger.kernel.org # v6.1+ Fixes: 8cf57d7217c3 ("s390: add support for user-defined certificates") Signed-off-by: Jarkko Sakkinen --- arch/s390/kernel/cert_store.c | 27 +++++++++++++++++++++++---- 1 file changed, 23 insertions(+), 4 deletions(-) diff --git a/arch/s390/kernel/cert_store.c b/arch/s390/kernel/cert_store.c index 998f2da56175..bb218b42a2c9 100644 --- a/arch/s390/kernel/cert_store.c +++ b/arch/s390/kernel/cert_store.c @@ -307,7 +307,6 @@ static struct key *get_user_session_keyring(void) PTR_ERR(us_keyring_ref)); return ERR_PTR(-ENOKEY); } - key_ref_put(us_keyring_ref); return key_ref_to_ptr(us_keyring_ref); } @@ -352,11 +351,17 @@ static int invalidate_keyring_keys(struct key *keyring) static struct key *find_cs_keyring(void) { key_ref_t cs_keyring_ref; + struct key *us_keyring; struct key *cs_keyring; - cs_keyring_ref = keyring_search(make_key_ref(get_user_session_keyring(), true), + us_keyring = get_user_session_keyring(); + if (IS_ERR(us_keyring)) + return NULL; + + cs_keyring_ref = keyring_search(make_key_ref(us_keyring, true), &key_type_keyring, CERT_STORE_KEYRING_NAME, false); + key_put(us_keyring); if (!IS_ERR(cs_keyring_ref)) { cs_keyring = key_ref_to_ptr(cs_keyring_ref); key_ref_put(cs_keyring_ref); @@ -373,6 +378,7 @@ static struct key *find_cs_keyring(void) static void cleanup_cs_keys(void) { + struct key *us_keyring; struct key *cs_keyring; cs_keyring = find_cs_keyring(); @@ -390,20 +396,33 @@ static void cleanup_cs_keys(void) keyring_clear(cs_keyring); key_invalidate(cs_keyring); key_put(cs_keyring); - key_unlink(get_user_session_keyring(), cs_keyring); + + us_keyring = get_user_session_keyring(); + if (IS_ERR(us_keyring)) + return; + + key_unlink(us_keyring, cs_keyring); + key_put(us_keyring); } static struct key *create_cs_keyring(void) { static struct key *cs_keyring; + struct key *us_keyring; /* Cleanup previous cs_keyring and all associated keys if any. */ cleanup_cs_keys(); + + us_keyring = get_user_session_keyring(); + if (IS_ERR(us_keyring)) + return NULL; + cs_keyring = keyring_alloc(CERT_STORE_KEYRING_NAME, GLOBAL_ROOT_UID, GLOBAL_ROOT_GID, current_cred(), (KEY_POS_ALL & ~KEY_POS_SETATTR) | KEY_USR_VIEW | KEY_USR_READ, KEY_ALLOC_NOT_IN_QUOTA | KEY_ALLOC_SET_KEEP, - NULL, get_user_session_keyring()); + NULL, us_keyring); + key_put(us_keyring); if (IS_ERR(cs_keyring)) { pr_dbf_msg("Can't allocate cert_store keyring"); return NULL; -- 2.47.3