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=1793208229; b=4ORZmpvvUKeiEAYMLLIk7mwyknxoiV21rF6eyIr5qb9ETTnBS8tEe/xqUsfnTV6WZRyO KYbGnLfFagmqLHgIXl+UrAoLYwyiJiJ3P7DndYqeaA47Tpw9CoRIPI5q6wd1MQtGP7dMd PgUZ8F8YxewX99zPLNYaElhtA4slmm2x0BLy6dLNPs6Wzn/66g3OfQdOU8MmbW96FfhTT Eds3rnjwB/h9/IOn8gmAYh3/fTx0TTIkgSXgjhR99WDsxDV95eTtl8SaNZFXSd39M24vY y2LbMRX+UJ9Cm6pJz8S8zrlGL+wgV3kMQ5fluVgbGzGD37NEx6XgckHrl52YVqS6rvw== ARC-Message-Signature: i=1; d=subspace.kernel.org; s=arc20261015; a=rsa-sha256; c=relaxed/relaxed; t=1793208229; 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=CYoUAF36lPR0nF6YimsH2J3efiNt/9UZ+g8qm7lkOdU=; b=YB3cVkkmXzRS4JEA+bxxQYZuZ+xUEm+bdk7xAS7yxFVab7Vwth6AkCDT90d5sKrkjz7U 2DcfMeZVx+23yY6zwZNXFgPJb+AcCPXGVXMabwli+0lkqmdLfx+Dbow36liCfT/RlXYhf cBZhzqNrNE5FblCCpCV1c6ht0b7ikD/1/1XsL7hsLeMlPAslYdQkgoQP9wPZByoaPl2ba sCBTnGxI7+j1F/klR7WRuwDxCDQVnstxK8ky8geq8YSGN9GtOfiWQglBRJvOHZsBEGRf5 4gL/Bn68x+DQHrObLac5eTzZ1ZWt5zXpysEqUnJjzexAZyJotEKe7YEF8zCqhJPhSPw== 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=tnGgFBrF; 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 34E61606A31C; Wed, 28 Oct 2026 17:23:49 +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=tnGgFBrF Received: by smtp.kernel.org (Postfix) with ESMTPSA id 85E411F01829; Wed, 28 Oct 2026 17:23:48 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linuxfoundation.org; s=korg; t=1793208229; bh=CYoUAF36lPR0nF6YimsH2J3efiNt/9UZ+g8qm7lkOdU=; h=From:To:Cc:Subject:Date:In-Reply-To:References; b=tnGgFBrFWMFkRhZIFzdx5XX3FSjWhJlPzgMSjvG3q/agC3W3Ch2BS+UCfuZepitIS J6cEqHpUJflZHtzYyM8gr4ynPmPuiVJWTHScTbhnLr1A2/q3D5oYjOtdWkvC/g64Ty Z3z50+WUWnLjkjmKBaU74evl94TAWPiyGDvSOScA= 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 5.10 044/516] KEYS: trusted: Fix TPM teardown ordering Date: Wed, 28 Oct 2026 17:53:16 +0100 Message-ID: <20261028170004.576402764@linuxfoundation.org> X-Mailer: git-send-email 2.56.0 In-Reply-To: <20261028170003.522232767@linuxfoundation.org> References: <20261028170003.522232767@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 5.10-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 3e9dc03d59c91..ca5efa7988e6a 100644 --- a/security/keys/trusted-keys/trusted_tpm1.c +++ b/security/keys/trusted-keys/trusted_tpm1.c @@ -1287,10 +1287,10 @@ static int __init init_trusted(void) static void __exit cleanup_trusted(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