Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752828Ab3J3AhE (ORCPT ); Tue, 29 Oct 2013 20:37:04 -0400 Received: from mout.gmx.net ([212.227.15.18]:60645 "EHLO mout.gmx.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751470Ab3J3AhB (ORCPT ); Tue, 29 Oct 2013 20:37:01 -0400 From: Peter Huewe To: Peter Huewe Cc: Ashley Lai , Rajiv Andrade , Marcel Selhorst , tpmdd-devel@lists.sourceforge.net, linux-kernel@vger.kernel.org, Xiaoyan Zhang , Gang Wei , stable@vger.kernel.org Subject: [PATCH 1/2] tpm/tpm_ppi: Do not compare strcmp(a,b) == -1 Date: Wed, 30 Oct 2013 01:40:27 +0100 Message-Id: <1383093628-31580-1-git-send-email-peterhuewe@gmx.de> X-Mailer: git-send-email 1.7.8.6 X-Provags-ID: V03:K0:XlkUzEREDthOFy6Yd7AdD7vbEvTU7fZTVxB3HsSBt49W5xKbVdK Z2ulf8ijhjdo3zEfw1lsgzqYmw5Foj8SxNtIXdbLDc1NjcJMBljXT9bwGjS/4zMaKP6K2No In6vhV4HLoJG9JSIY+/hIKroc0DydpOJgJV3JeTdS/iltrgr1ne5Brmhu/PQpuP0Yh+kJUq GwhGMOQGXTFTGspxKNPLQ== Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 2519 Lines: 69 strcmp does return the difference between two strings not only -1,0,1 consequently if (strcmp (a,b) == -1) might lead to taking the wrong branch -> compare with <= instead. This also makes the code/behavior compliant with its comments. (e.g. if PPI Version is 1.0) Fixes Coverity complaints: CID: 741083 Misuse of memcmp-style function CID: 741084 Misuse of memcmp-style function CID: 741085 Misuse of memcmp-style function Cc: stable@vger.kernel.org Signed-off-by: Peter Huewe --- drivers/char/tpm/tpm_ppi.c | 8 ++++---- 1 files changed, 4 insertions(+), 4 deletions(-) diff --git a/drivers/char/tpm/tpm_ppi.c b/drivers/char/tpm/tpm_ppi.c index 8e562dc..8b2e05a 100644 --- a/drivers/char/tpm/tpm_ppi.c +++ b/drivers/char/tpm/tpm_ppi.c @@ -169,7 +169,7 @@ static ssize_t tpm_store_ppi_request(struct device *dev, * is updated with function index from SUBREQ to SUBREQ2 since PPI * version 1.1 */ - if (strcmp(version, "1.1") == -1) + if (strcmp(version, "1.1") <= -1) params[2].integer.value = TPM_PPI_FN_SUBREQ; else params[2].integer.value = TPM_PPI_FN_SUBREQ2; @@ -179,7 +179,7 @@ static ssize_t tpm_store_ppi_request(struct device *dev, * string/package type. For PPI version 1.0 and 1.1, use buffer type * for compatibility, and use package type since 1.2 according to spec. */ - if (strcmp(version, "1.2") == -1) { + if (strcmp(version, "1.2") <= -1) { params[3].type = ACPI_TYPE_BUFFER; params[3].buffer.length = sizeof(req); sscanf(buf, "%d", &req); @@ -245,7 +245,7 @@ static ssize_t tpm_show_ppi_transition_action(struct device *dev, * (e.g. Capella with PPI 1.0) need integer/string/buffer type, so for * compatibility, define params[3].type as buffer, if PPI version < 1.2 */ - if (strcmp(version, "1.2") == -1) { + if (strcmp(version, "1.2") <= -1) { params[3].type = ACPI_TYPE_BUFFER; params[3].buffer.length = 0; params[3].buffer.pointer = NULL; @@ -387,7 +387,7 @@ static ssize_t show_ppi_operations(char *buf, u32 start, u32 end) kfree(output.pointer); output.length = ACPI_ALLOCATE_BUFFER; output.pointer = NULL; - if (strcmp(version, "1.2") == -1) + if (strcmp(version, "1.2") <= -1) return -EPERM; params[2].integer.value = TPM_PPI_FN_GETOPR; -- 1.7.8.6 -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/