From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (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 92E293806B4 for ; Mon, 9 Mar 2026 10:22:54 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1773051774; cv=none; b=ZHTyaOFcBthnFnkVSXeRkB/YGsaK/GfehLUBDNFzKKRm9rG9HzKBm+LV/JVnYb7/SRndWKEm3NAn0B1uvttFsZD+d/oalHZ65LegeVpBYTcQNIT/JsbrnBOLFHA1/kkAiz0aWLy/yv/hgxvXKu+O8k3pzax/6rn10KlIHQ+PNBY= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1773051774; c=relaxed/simple; bh=ZF69Wlgn5ML/uhTwSvHiJdfj9/4UR0yi9gNrplNyd40=; h=Subject:To:Cc:From:Date:Message-ID:MIME-Version:Content-Type; b=rMKVOv12swkrix0I66Z+XhlQu1mBb6H3ZcJ7W/0AIfsoKFl7mtS2V5/OcO/v1yi79MjIbWrsBb3mefbYZChqCd2kYl7lXsjARkJifx9KQdU4TP3ZoABBkDeGrie5Kz5xAZvbi/YmfT/hKcvhSYQqzfVakdSzYxVsEXOqdlGcikQ= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b=Fi58MjGf; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b="Fi58MjGf" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 2822FC4CEF7; Mon, 9 Mar 2026 10:22:53 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1773051774; bh=ZF69Wlgn5ML/uhTwSvHiJdfj9/4UR0yi9gNrplNyd40=; h=Subject:To:Cc:From:Date:From; b=Fi58MjGfWpOCd3zT+QwNr4XrYKE08YNgylyl/nzX4vVmOOONU8WqPpY+9VhhIzD2G 82dkIkKO64NIZ9nEZ380IoA47QmK/IrzVHySKTzLhRPeWPoh42pADUH1K6SjHeIVJD 6A1gow/pzwC6OJ/YGLSckZD6r+QhUiU8nTk+Ni0Q= Subject: FAILED: patch "[PATCH] ksmbd: Compare MACs in constant time" failed to apply to 6.1-stable tree To: ebiggers@kernel.org,linkinjeon@kernel.org,stfrench@microsoft.com Cc: From: Date: Mon, 09 Mar 2026 11:22:37 +0100 Message-ID: <2026030937-ship-unsuited-7745@gregkh> Precedence: bulk X-Mailing-List: stable@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=ANSI_X3.4-1968 Content-Transfer-Encoding: 8bit The patch below does not apply to the 6.1-stable tree. If someone wants it applied there, or to any other stable or longterm tree, then please email the backport, including the original git commit id to . To reproduce the conflict and resubmit, you may use the following commands: git fetch https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/ linux-6.1.y git checkout FETCH_HEAD git cherry-pick -x c5794709bc9105935dbedef8b9cf9c06f2b559fa # git commit -s git send-email --to '' --in-reply-to '2026030937-ship-unsuited-7745@gregkh' --subject-prefix 'PATCH 6.1.y' HEAD^.. Possible dependencies: thanks, greg k-h ------------------ original commit in Linus's tree ------------------ >From c5794709bc9105935dbedef8b9cf9c06f2b559fa Mon Sep 17 00:00:00 2001 From: Eric Biggers Date: Tue, 17 Feb 2026 20:28:29 -0800 Subject: [PATCH] ksmbd: Compare MACs in constant time To prevent timing attacks, MAC comparisons need to be constant-time. Replace the memcmp() with the correct function, crypto_memneq(). Fixes: e2f34481b24d ("cifsd: add server-side procedures for SMB3") Cc: stable@vger.kernel.org Signed-off-by: Eric Biggers Acked-by: Namjae Jeon Signed-off-by: Steve French diff --git a/fs/smb/server/Kconfig b/fs/smb/server/Kconfig index 2775162c535c..12594879cb64 100644 --- a/fs/smb/server/Kconfig +++ b/fs/smb/server/Kconfig @@ -13,6 +13,7 @@ config SMB_SERVER select CRYPTO_LIB_MD5 select CRYPTO_LIB_SHA256 select CRYPTO_LIB_SHA512 + select CRYPTO_LIB_UTILS select CRYPTO_CMAC select CRYPTO_AEAD2 select CRYPTO_CCM diff --git a/fs/smb/server/auth.c b/fs/smb/server/auth.c index 580c4d303dc3..5fe8c667c6b1 100644 --- a/fs/smb/server/auth.c +++ b/fs/smb/server/auth.c @@ -15,6 +15,7 @@ #include #include #include +#include #include #include @@ -165,7 +166,8 @@ int ksmbd_auth_ntlmv2(struct ksmbd_conn *conn, struct ksmbd_session *sess, ntlmv2_rsp, CIFS_HMAC_MD5_HASH_SIZE, sess->sess_key); - if (memcmp(ntlmv2->ntlmv2_hash, ntlmv2_rsp, CIFS_HMAC_MD5_HASH_SIZE) != 0) + if (crypto_memneq(ntlmv2->ntlmv2_hash, ntlmv2_rsp, + CIFS_HMAC_MD5_HASH_SIZE)) return -EINVAL; return 0; } diff --git a/fs/smb/server/smb2pdu.c b/fs/smb/server/smb2pdu.c index 95901a78951c..743c629fe7ec 100644 --- a/fs/smb/server/smb2pdu.c +++ b/fs/smb/server/smb2pdu.c @@ -4,6 +4,7 @@ * Copyright (C) 2018 Samsung Electronics Co., Ltd. */ +#include #include #include #include @@ -8880,7 +8881,7 @@ int smb2_check_sign_req(struct ksmbd_work *work) ksmbd_sign_smb2_pdu(work->conn, work->sess->sess_key, iov, 1, signature); - if (memcmp(signature, signature_req, SMB2_SIGNATURE_SIZE)) { + if (crypto_memneq(signature, signature_req, SMB2_SIGNATURE_SIZE)) { pr_err("bad smb2 signature\n"); return 0; } @@ -8968,7 +8969,7 @@ int smb3_check_sign_req(struct ksmbd_work *work) if (ksmbd_sign_smb3_pdu(conn, signing_key, iov, 1, signature)) return 0; - if (memcmp(signature, signature_req, SMB2_SIGNATURE_SIZE)) { + if (crypto_memneq(signature, signature_req, SMB2_SIGNATURE_SIZE)) { pr_err("bad smb2 signature\n"); return 0; }