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 9DF1953B333; Wed, 23 Sep 2026 14:48:30 +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=1790174911; cv=none; b=duKNcer8QygjlrPddCfycSiSMw1oJ95VtXQVuhgCXv0UiAYcualAy3BOq7+ZjyjiCwr9PYKtWdkxysuQvJTWlQZnJnohpPwgA3x0Ls5URPqp42N+QwMWyRrchk3FPmkTb1sLIJzZDyEUmvHY3jQZvjZHoblg9v4fFQ3dRNr4GoE= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1790174911; c=relaxed/simple; bh=L33zpBf1Ws093DPgX2Uw9xrYLq3fpsGqDaTQuCe6hqE=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=DLg16e4J9FgjiyIMvcBbnEAIPMQBDwufWev4BWJ+5nF3WmME01cQgumNRhOmy/FvN4aGaiCCE1xD6KP1a/Pbw27/FdypQV5VG/NIvj3DSMmpmiG7wLs6AptHL0wzoFYhTZ8S0NQlKwer8sr9kcuftcwKiZR+s4lUvulmFvIG/QA= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b=gxJi96Bt; 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="gxJi96Bt" Received: by smtp.kernel.org (Postfix) with ESMTPSA id CDBE21F000FF; Wed, 23 Sep 2026 14:48:29 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linuxfoundation.org; s=korg; t=1790174910; bh=vT0/FlmhJew9cKVO1wHrP1rNhDBxmejzaFFz1MsIHi0=; h=From:To:Cc:Subject:Date:In-Reply-To:References; b=gxJi96BtbGQUiJJuZwQuFZOORwJ6BAfS7R+DcIIW8wgbRkHWi1bKefQOtx3lYV3B5 wfQ65y5ii/Dem1jJNlQyDPYtIGM5qrk52WkN9XnDC6bJoCuRIgb4nSbJaEwfa2AgFh IKz32DXuaSdxvE/hazJvCjjr5JkI6GATKPmJQkUk= 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 6.18 263/398] KEYS: encrypted: fix integer overflow of datablob_len Date: Wed, 23 Sep 2026 16:05:37 +0200 Message-ID: <20260923140650.228565453@linuxfoundation.org> X-Mailer: git-send-email 2.55.0 In-Reply-To: <20260923140643.441954610@linuxfoundation.org> References: <20260923140643.441954610@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 6.18-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 @@ -18,6 +18,7 @@ #include #include #include +#include #include #include #include @@ -578,6 +579,7 @@ 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; @@ -631,16 +633,22 @@ 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);