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=1793212189; b=beWH2YgBv7d7QJpBd2AZQFO6a7Jclzy6/CEWef4C+4cBS12TFpUnFhosX8xLsLpRaIqi v9cewpyupIdLHOLFUnPsyKNqBm2kIi+K1/DnOQXRU5VkLdx5erMqd5BL7Lgv9QtCidJsZ xQCh3ac11fwJhcViPOczV/M6cFNXt8l0DTFJKXjsX22cw0Kdgo8CEH9svF3g7/XBrmTLH ToKhsQZv7m39AVQH+p5kUWEeEI8LdEhrl/i4xubnHd+baJASKN7qVdxOaAROXoDIMv7hn Zf8xURw3hGM9hSUM0/zNI8DWvocZ8UfPVYsrlR2nukTMfIqP8XoE0oEqL6io0nWzsLg== ARC-Message-Signature: i=1; d=subspace.kernel.org; s=arc20261015; a=rsa-sha256; c=relaxed/relaxed; t=1793212189; h=Received:DKIM-Signature:From:To:Cc:Subject:Date:Message-ID:X-Mailer: In-Reply-To:References:User-Agent:X-stable:X-Patchwork-Hint: MIME-Version:Content-Transfer-Encoding; bh=THfMrh4F5coYew9qPAnt26W/d9zQoauNj0iu7ESCKgQ=; b=JB9EsQd6MGiIzODCYHRE/jwaBQqZuG7oOEcgtVjLUVUUXmY/hfFLpqDCjLiDkU35Uznc wQAAu7Yk5bfHzb4h6BecrAL9WfClRO7oXboyfOHAJIyYuPq7VnLPOVkeuVMe8PEgkmo3s ulTvXr+6DDlGLXCzxGz0GiuIutehve1/GUzgbuokuH525Ebuiux0yQAdiR9862zJlwTMP FuBEBDaEyoEt4M1DMXlF0NzfXQW4SUF5NmSKCd0Q90xDv8Jz8kh0UdINzAOFICwuRRNWM GUpbE+qhkXMyl+6U4nmZwvsYX9Ebin0vTrfyh3ugBfZFdW+VR4zRbI/dI/NxTZYWTrA== ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dkim=pass header.d=linuxfoundation.org header.i=@linuxfoundation.org header.a=rsa-sha256 header.s=korg header.b=Da7HiadM; 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 ESMTPS id 59D7F606A320; Wed, 28 Oct 2026 18:29:49 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key, unprotected) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.a=rsa-sha256 header.s=korg header.b=Da7HiadM Received: by smtp.kernel.org (Postfix) with ESMTPSA id AA5541F01825; Wed, 28 Oct 2026 18:29:48 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linuxfoundation.org; s=korg; t=1793212189; bh=THfMrh4F5coYew9qPAnt26W/d9zQoauNj0iu7ESCKgQ=; h=From:To:Cc:Subject:Date:In-Reply-To:References; b=Da7HiadMners/1PP/dxDM6BKJW3ChzPwM0WaucZVJ7AZuFjbOtVxoP3d73MsQh6by N6jTVoGQTxmGpfNIDZ2A8XsxjF9FeOjFhUxZrp+x2sN0bZvivb7tLOG17iGybn6Cqm 534Hj13PTSn+ARnYRkznqencSWGDGkuSLd+mMsCY= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, Chengfeng Ye , Jarkko Sakkinen , Sasha Levin Subject: [PATCH 6.1 0062/1887] KEYS: trusted: Fix TPM teardown ordering Date: Wed, 28 Oct 2026 17:35:58 +0100 Message-ID: <20261028170500.640174275@linuxfoundation.org> X-Mailer: git-send-email 2.56.0 In-Reply-To: <20261028170459.200466217@linuxfoundation.org> References: <20261028170459.200466217@linuxfoundation.org> User-Agent: quilt/0.69 X-stable: review X-Patchwork-Hint: ignore X-Mailing-List: patches@lists.linux.dev List-Id: List-Post: List-Help: List-Subscribe: List-Unsubscribe: List-Owner: Precedence: list MIME-Version: 1.0 Content-Transfer-Encoding: 8bit 6.1-stable review patch. If anyone has any objections, please let me know. ------------------ From: Chengfeng Ye [ Upstream commit 5e2d672280d97d83de43031d93761b12dadd7b8a ] trusted_tpm_exit() drops the TPM chip reference and frees the digest array before unregistering the trusted key type. key_type_lookup() holds key_types_sem for reading until the key operation finishes, while unregister_key_type() takes it for writing. It therefore provides the synchronization point that must precede backend teardown. The current order permits this interleaving: CPU 0 CPU 1 trusted_tpm_exit() key_type_lookup("trusted") put_device(&chip->dev) trusted_tpm_seal() kfree(digests) pcrlock() unregister_key_type() tpm_pcr_extend(..., digests) CPU 1 can consequently dereference the freed digest array. The chip can also be released before callbacks stop using it. KASAN reported: BUG: KASAN: slab-use-after-free in tpm_pcr_extend+0x1f0/0x200 Read of size 2 at addr ffff88810872d000 by task poc/89 Call Trace: tpm_pcr_extend+0x1f0/0x200 pcrlock+0x42/0x70 [trusted] trusted_tpm_seal+0x1b6/0x570 [trusted] trusted_instantiate+0x293/0x340 [trusted] __key_instantiate_and_link+0xb2/0x2b0 __key_create_or_update+0x61e/0xb50 __do_sys_add_key+0x1b8/0x310 Allocated by task 88: __kmalloc_noprof+0x1a7/0x490 do_one_initcall+0xa1/0x390 do_init_module+0x2df/0x840 Freed by task 90: kfree+0x131/0x3c0 trusted_tpm_exit+0x59/0xa0 [trusted] __do_sys_delete_module+0x346/0x510 Move unregister_key_type() before releasing either resource. This stops new lookups and waits for in-flight key operations to finish before the backend state is destroyed. Fixes: 0b6cf6b97b7e ("tpm: pass an array of tpm_extend_digest structures to tpm_pcr_extend()") Cc: stable@vger.kernel.org Signed-off-by: Chengfeng Ye Link: https://lore.kernel.org/r/20260731140925.2973492-1-nicoyip.dev@gmail.com Reviewed-by: Jarkko Sakkinen Tested-by: Jarkko Sakkinen Signed-off-by: Jarkko Sakkinen [ preserved the additional trusted_shash_release() cleanup after unregister_key_type() ] Signed-off-by: Sasha Levin --- security/keys/trusted-keys/trusted_tpm1.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/security/keys/trusted-keys/trusted_tpm1.c b/security/keys/trusted-keys/trusted_tpm1.c index 4863ee08b7b11..c482c54be918c 100644 --- a/security/keys/trusted-keys/trusted_tpm1.c +++ b/security/keys/trusted-keys/trusted_tpm1.c @@ -1058,10 +1058,10 @@ static int __init trusted_tpm_init(void) static void trusted_tpm_exit(void) { if (chip) { + unregister_key_type(&key_type_trusted); put_device(&chip->dev); kfree(digests); trusted_shash_release(); - unregister_key_type(&key_type_trusted); } } -- 2.53.0