From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-alma10-1.taild15c8.ts.net [100.103.45.18]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 0F5C65293E9; Wed, 23 Sep 2026 14:27:55 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=100.103.45.18 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1790173676; cv=none; b=bODB0EmuSvGrvlxrxNHG2C9rLkqXbjS6yATZfyME0v5EjWRnDp6bFv+ulYqH7eUJtBi26y2NauBxWL/EDfexAipDbCl0FY3eR6pELTQSBZjSXfdVkRWAspdhYxl3dOs6+jnZkfYF7m3MQXIjYF8CjeKozq5qsAKe+LgHryCRMDA= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1790173676; c=relaxed/simple; bh=MXRCrGBOHk1nPWOh8Ft28rhjscJnFojs2ly2jnTjFi8=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=d8ijTDD3zHADA9tpBCS3XqvUlkSlLPUhhZImS+JkJvVQOSARJwJFediulHqx1sUSVSbkuJhM17ja6TE11F8ecrH/yYeCTt/mXgWclrH+wl93SpH7g1n6SOo08VXqdvUL5FomRPsREIajW3DDcRay3tQxIy46so8fnklucQJigsg= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b=I2AZrlVP; arc=none smtp.client-ip=100.103.45.18 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b="I2AZrlVP" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 6A4141F00893; Wed, 23 Sep 2026 14:27:54 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linuxfoundation.org; s=korg; t=1790173675; bh=rMcNt1oba2QEpptl61mXxIYhiWegb+jN0H4mX18H/sA=; h=From:To:Cc:Subject:Date:In-Reply-To:References; b=I2AZrlVPmDVBdnEV2BF1qI2/MGe/eR7Krb0FcCEbBowrp7n1AWU164SxGcsjGYgVt eNcnt7WpWe+btqER5cZVg7Mb8EaggKnWIGmsvXHEN5YwZNbU3mUy/auSbe952EgX29 vrRAPZ/cHMu6D4HTLISroHsHHeB/Usroj3blXt1s= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, Cen Zhang , Francis Perron , Jarkko Sakkinen , R Nageswara Sastry Subject: [PATCH 7.2 320/438] KEYS: encrypted: fix integer overflow of datablob_len Date: Wed, 23 Sep 2026 16:05:41 +0200 Message-ID: <20260923140653.090060579@linuxfoundation.org> X-Mailer: git-send-email 2.55.0 In-Reply-To: <20260923140644.756254324@linuxfoundation.org> References: <20260923140644.756254324@linuxfoundation.org> User-Agent: quilt/0.69 X-stable: review X-Patchwork-Hint: ignore Precedence: bulk X-Mailing-List: patches@lists.linux.dev List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit 7.2-stable review patch. If anyone has any objections, please let me know. ------------------ From: Cen Zhang commit 8697c431e297eb0d0ab13dda6bc172b48a34f05c upstream. encrypted_key_alloc() stores datablob_len in a u16. It is computed from multiple string and payload lengths. If the result exceeds U16_MAX, the assignment truncates the allocation size. KASAN reports a 32760-byte slab-out-of-bounds write when __ekey_init() copies the master key description into the undersized buffer. The total payload length stored in key->datalen is also a u16. Use check_add_overflow() to reject values that do not fit either destination, and use kzalloc_flex() for the flexible-array allocation. Fixes: 7e70cb497850 ("keys: add new key-type encrypted") Cc: stable@vger.kernel.org Assisted-by: GitHub-Copilot:claude-opus-4.6 Signed-off-by: Cen Zhang Signed-off-by: Francis Perron Reviewed-by: Jarkko Sakkinen Tested-by: R Nageswara Sastry Link: https://lore.kernel.org/r/20260909153433.83117-1-cenzhang@linux.microsoft.com Signed-off-by: Jarkko Sakkinen Signed-off-by: Greg Kroah-Hartman --- security/keys/encrypted-keys/encrypted.c | 20 ++++++++++++++------ 1 file changed, 14 insertions(+), 6 deletions(-) --- a/security/keys/encrypted-keys/encrypted.c +++ b/security/keys/encrypted-keys/encrypted.c @@ -19,6 +19,7 @@ #include #include #include +#include #include #include #include @@ -579,6 +580,7 @@ static struct encrypted_key_payload *enc { struct encrypted_key_payload *epayload = NULL; unsigned short datablob_len; + unsigned short payload_totallen; unsigned short decrypted_datalen; unsigned short payload_datalen; unsigned int encrypted_datalen; @@ -632,16 +634,22 @@ static struct encrypted_key_payload *enc encrypted_datalen = roundup(decrypted_datalen, blksize); - datablob_len = format_len + 1 + strlen(master_desc) + 1 - + strlen(datalen) + 1 + ivsize + 1 + encrypted_datalen; + if (check_add_overflow(format_len + 1 + strlen(master_desc) + 1 + + strlen(datalen) + 1 + ivsize + 1, + encrypted_datalen, &datablob_len)) + return ERR_PTR(-EINVAL); + + if (check_add_overflow(datablob_len, + payload_datalen + HASH_SIZE + 1, + &payload_totallen)) + return ERR_PTR(-EINVAL); - ret = key_payload_reserve(key, payload_datalen + datablob_len - + HASH_SIZE + 1); + ret = key_payload_reserve(key, payload_totallen); if (ret < 0) return ERR_PTR(ret); - epayload = kzalloc(sizeof(*epayload) + payload_datalen + - datablob_len + HASH_SIZE + 1, GFP_KERNEL); + epayload = kzalloc_flex(*epayload, payload_data, payload_totallen, + GFP_KERNEL); if (!epayload) return ERR_PTR(-ENOMEM);