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=-16.8 required=3.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER,INCLUDES_PATCH, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,USER_AGENT_GIT autolearn=ham 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 A68F8C07E9D for ; Mon, 19 Jul 2021 23:39:40 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 99F65610F7 for ; Mon, 19 Jul 2021 23:39:40 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1346541AbhGSW6O (ORCPT ); Mon, 19 Jul 2021 18:58:14 -0400 Received: from mail-pj1-f46.google.com ([209.85.216.46]:41552 "EHLO mail-pj1-f46.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S243150AbhGSWa5 (ORCPT ); Mon, 19 Jul 2021 18:30:57 -0400 Received: by mail-pj1-f46.google.com with SMTP id jx7-20020a17090b46c7b02901757deaf2c8so1389263pjb.0 for ; Mon, 19 Jul 2021 16:11:37 -0700 (PDT) X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:from:to:cc:subject:date:message-id:mime-version :content-transfer-encoding; bh=I526wSzOkW00CVxYXad8tWeRPw9m3Gt17/KZq068/AA=; b=fN2Kv4Yce9HmRQ4wTAkKI2dKTlQqinvSOx5E5DBmqTZhIa1oQ7yEvTvlxhu6/uOxxA xaIRZ+XZoY5doEJ4lriZamIxDjNlZkpilcCRbDexTaWHweR1Ht5Vb2N/d7kQruVIrkLH IBry/8vnuMiYPLML0PsLClA/G4tDDwlh4J07Essj8qTvxemDHmfG11CG7CEiMXK+kibe gKyEkG7giC/sR1iQ0N3mtUZS26MsMTOg9hz2U/79qAen++Q/SLfuvlPZtLu34VFyR+uF 9LlqIhPX1r0uIr3GSK4XTyC39A3ei9/IXOVdSyaBuEKV1RR5uX/f5mwLlKLc9/8id8Db swAg== X-Gm-Message-State: AOAM5304UCfcGtLgL61r0D1d2QXSUqeuxk6VyT4OMCxT4DNnKfYKFLZK VNFAwnIYfI1o0LY3t8wg+aw= X-Google-Smtp-Source: ABdhPJx+gMyR3YFvAvIePUmM2o9//jognnaCMgE3wvh6dbcj7DPA+xF3mn1Rq3GsJotcRJrS4Af1Zg== X-Received: by 2002:a17:90b:3617:: with SMTP id ml23mr26792259pjb.236.1626736296849; Mon, 19 Jul 2021 16:11:36 -0700 (PDT) Received: from bvanassche-glaptop.corp.google.com ([2620:0:1000:2004:b968:4d11:8f24:cf85]) by smtp.gmail.com with ESMTPSA id n32sm20855140pfv.59.2021.07.19.16.11.34 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Mon, 19 Jul 2021 16:11:35 -0700 (PDT) From: Bart Van Assche To: "Martin K . Petersen" Cc: Jaegeuk Kim , linux-scsi@vger.kernel.org, Bart Van Assche , "James E.J. Bottomley" , Can Guo , Stanley Chu , Bean Huo , Avri Altman , Asutosh Das Subject: [PATCH] scsi: ufs: Fix memory corruption by ufshcd_read_desc_param() Date: Mon, 19 Jul 2021 16:11:22 -0700 Message-Id: <20210719231127.869088-1-bvanassche@acm.org> X-Mailer: git-send-email 2.32.0.402.g57bb445576-goog MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: linux-scsi@vger.kernel.org If param_offset > buff_len then the memcpy() statement in ufshcd_read_desc_param() corrupts memory since it copies 256 + buff_len - param_offset bytes into a buffer with size buff_len. Since param_offset < 256 this results in writing past the bound of the output buffer. Fixes: cbe193f6f093 ("scsi: ufs: Fix potential NULL pointer access during memcpy") Signed-off-by: Bart Van Assche --- drivers/scsi/ufs/ufshcd.c | 4 +++- 1 file changed, 3 insertions(+), 1 deletion(-) diff --git a/drivers/scsi/ufs/ufshcd.c b/drivers/scsi/ufs/ufshcd.c index 89da2cf2c969..00502ffe9b4a 100644 --- a/drivers/scsi/ufs/ufshcd.c +++ b/drivers/scsi/ufs/ufshcd.c @@ -3365,7 +3365,9 @@ int ufshcd_read_desc_param(struct ufs_hba *hba, if (is_kmalloc) { /* Make sure we don't copy more data than available */ - if (param_offset + param_size > buff_len) + if (buff_len < param_offset) + param_size = 0; + else if (param_offset + param_size > buff_len) param_size = buff_len - param_offset; memcpy(param_read_buf, &desc_buf[param_offset], param_size); }