From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 53F3EC433F5 for ; Mon, 18 Oct 2021 13:52:30 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 3E04660EE3 for ; Mon, 18 Oct 2021 13:52:30 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S233951AbhJRNyi (ORCPT ); Mon, 18 Oct 2021 09:54:38 -0400 Received: from mail.kernel.org ([198.145.29.99]:56112 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S233868AbhJRNwF (ORCPT ); Mon, 18 Oct 2021 09:52:05 -0400 Received: by mail.kernel.org (Postfix) with ESMTPSA id B80D36137C; Mon, 18 Oct 2021 13:38:41 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1634564322; bh=b3aGtohO717TSNZ0ihvaEzIUwQ0LZ7WFoe7mE075hAY=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=19AmSyPMpqJfpNBdWL8aQZJ22FrH2UXhQlrF2GMN7Q007qJzIdb0uOWEZ62WDREfL 8ryZQrUzV3yNGv6cwIlF3mqjqqvNucit685tbH1MKH6F4iqHStSAMPNypIyBIHnprd MFEH6GXsKPoVrdAbMmt/3bQifrrZlhGmzePwSfl4= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Joe Perches , Ard Biesheuvel Subject: [PATCH 5.14 046/151] efi/cper: use stack buffer for error record decoding Date: Mon, 18 Oct 2021 15:23:45 +0200 Message-Id: <20211018132342.199309377@linuxfoundation.org> X-Mailer: git-send-email 2.33.1 In-Reply-To: <20211018132340.682786018@linuxfoundation.org> References: <20211018132340.682786018@linuxfoundation.org> User-Agent: quilt/0.66 MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Ard Biesheuvel commit b3a72ca80351917cc23f9e24c35f3c3979d3c121 upstream. Joe reports that using a statically allocated buffer for converting CPER error records into human readable text is probably a bad idea. Even though we are not aware of any actual issues, a stack buffer is clearly a better choice here anyway, so let's move the buffer into the stack frames of the two functions that refer to it. Cc: Reported-by: Joe Perches Signed-off-by: Ard Biesheuvel Signed-off-by: Greg Kroah-Hartman --- drivers/firmware/efi/cper.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) --- a/drivers/firmware/efi/cper.c +++ b/drivers/firmware/efi/cper.c @@ -25,8 +25,6 @@ #include #include -static char rcd_decode_str[CPER_REC_LEN]; - /* * CPER record ID need to be unique even after reboot, because record * ID is used as index for ERST storage, while CPER records from @@ -313,6 +311,7 @@ const char *cper_mem_err_unpack(struct t struct cper_mem_err_compact *cmem) { const char *ret = trace_seq_buffer_ptr(p); + char rcd_decode_str[CPER_REC_LEN]; if (cper_mem_err_location(cmem, rcd_decode_str)) trace_seq_printf(p, "%s", rcd_decode_str); @@ -327,6 +326,7 @@ static void cper_print_mem(const char *p int len) { struct cper_mem_err_compact cmem; + char rcd_decode_str[CPER_REC_LEN]; /* Don't trust UEFI 2.1/2.2 structure with bad validation bits */ if (len == sizeof(struct cper_sec_mem_err_old) &&