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 X-Spam-Level: X-Spam-Status: No, score=-15.8 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER, INCLUDES_PATCH,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED autolearn=unavailable autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id D01ACC433DB for ; Tue, 29 Dec 2020 23:15:53 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id A015620771 for ; Tue, 29 Dec 2020 23:15:53 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726289AbgL2XPx (ORCPT ); Tue, 29 Dec 2020 18:15:53 -0500 Received: from mail.kernel.org ([198.145.29.99]:37886 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726161AbgL2XPx (ORCPT ); Tue, 29 Dec 2020 18:15:53 -0500 Received: by mail.kernel.org (Postfix) with ESMTPSA id 0B236223DB; Tue, 29 Dec 2020 23:15:02 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linux-foundation.org; s=korg; t=1609283702; bh=I+kANtDsJWBoHJ0KQZKqJmAYuK8D3gsAukkRlX/7QCI=; h=Date:From:To:Subject:In-Reply-To:From; b=CtY4oX0zTLAE2dJBLxDOUdDiDo0R01dc7Tx6WhjESeNp+PoaTLkcP1NA4w+R6xF5V eBIGghV4Vk6zt65SU+LRyVBRmqiQACrYXS5wzXAfJc6h2C4XormG5YGHmqrX4Uz0Dx 3BFe+GLfxuzo+ShKMaLU248iKc5GiOi5aLVDHuVY= Date: Tue, 29 Dec 2020 15:15:01 -0800 From: Andrew Morton To: akpm@linux-foundation.org, borntraeger@de.ibm.com, gor@linux.ibm.com, hca@linux.ibm.com, iii@linux.ibm.com, linux-mm@kvack.org, mm-commits@vger.kernel.org, stable@vger.kernel.org, torvalds@linux-foundation.org, zaslonko@linux.ibm.com Subject: [patch 14/16] lib/zlib: fix inflating zlib streams on s390 Message-ID: <20201229231501.ix0FESQg2%akpm@linux-foundation.org> In-Reply-To: <20201229151349.3285926ec0d1f65a27ac8534@linux-foundation.org> User-Agent: s-nail v14.8.16 Precedence: bulk Reply-To: linux-kernel@vger.kernel.org List-ID: X-Mailing-List: mm-commits@vger.kernel.org From: Ilya Leoshkevich Subject: lib/zlib: fix inflating zlib streams on s390 Decompressing zlib streams on s390 fails with "incorrect data check" error. Userspace zlib checks inflate_state.flags in order to byteswap checksums only for zlib streams, and s390 hardware inflate code, which was ported from there, tries to match this behavior. At the same time, kernel zlib does not use inflate_state.flags, so it contains essentially random values. For many use cases either zlib stream is zeroed out or checksum is not used, so this problem is masked, but at least SquashFS is still affected. Fix by always passing a checksum to and from the hardware as is, which matches zlib_inflate()'s expectations. Link: https://lkml.kernel.org/r/20201215155551.894884-1-iii@linux.ibm.com Fixes: 126196100063 ("lib/zlib: add s390 hardware support for kernel zlib_inflate") Signed-off-by: Ilya Leoshkevich Tested-by: Christian Borntraeger Acked-by: Mikhail Zaslonko Acked-by: Christian Borntraeger Cc: Heiko Carstens Cc: Vasily Gorbik Cc: Mikhail Zaslonko Cc: [5.6+] Signed-off-by: Andrew Morton --- lib/zlib_dfltcc/dfltcc_inflate.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) --- a/lib/zlib_dfltcc/dfltcc_inflate.c~lib-zlib-fix-inflating-zlib-streams-on-s390 +++ a/lib/zlib_dfltcc/dfltcc_inflate.c @@ -125,7 +125,7 @@ dfltcc_inflate_action dfltcc_inflate( param->ho = (state->write - state->whave) & ((1 << HB_BITS) - 1); if (param->hl) param->nt = 0; /* Honor history for the first block */ - param->cv = state->flags ? REVERSE(state->check) : state->check; + param->cv = state->check; /* Inflate */ do { @@ -138,7 +138,7 @@ dfltcc_inflate_action dfltcc_inflate( state->bits = param->sbb; state->whave = param->hl; state->write = (param->ho + param->hl) & ((1 << HB_BITS) - 1); - state->check = state->flags ? REVERSE(param->cv) : param->cv; + state->check = param->cv; if (cc == DFLTCC_CC_OP2_CORRUPT && param->oesc != 0) { /* Report an error if stream is corrupted */ state->mode = BAD; _