Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1030454Ab2JSDCa (ORCPT ); Thu, 18 Oct 2012 23:02:30 -0400 Received: from mail.kernel.org ([198.145.19.201]:52134 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S964897Ab2JSCsu (ORCPT ); Thu, 18 Oct 2012 22:48:50 -0400 From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org, stable@vger.kernel.org Cc: Greg Kroah-Hartman , alan@lxorguk.ukuu.org.uk, Paolo Bonzini , Nicholas Bellinger Subject: [ 30/76] target: fix truncation of mode data, support zero allocation length Date: Thu, 18 Oct 2012 19:46:54 -0700 Message-Id: <20121019024354.985523098@linuxfoundation.org> X-Mailer: git-send-email 1.8.0.rc0.18.gf84667d In-Reply-To: <20121019024350.087156547@linuxfoundation.org> References: <20121019024350.087156547@linuxfoundation.org> User-Agent: quilt/0.60-2.1.2 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 2798 Lines: 88 3.6-stable review patch. If anyone has any objections, please let me know. ------------------ From: Paolo Bonzini commit 7a3f369ce31694017996524a1cdb08208a839077 upstream. The offset was not bumped back to the full size after writing the header of the MODE SENSE response, so the last 1 or 2 bytes were not copied. On top of this, support zero-length requests by checking for the return value of transport_kmap_data_sg. Testcase: sg_raw -r20 /dev/sdb 5a 00 0a 00 00 00 00 00 14 00 last byte should be 0x1e it is 0x00 without the patch it is correct with the patch Signed-off-by: Paolo Bonzini Signed-off-by: Nicholas Bellinger Signed-off-by: Greg Kroah-Hartman --- drivers/target/target_core_spc.c | 17 +++++++---------- 1 file changed, 7 insertions(+), 10 deletions(-) --- a/drivers/target/target_core_spc.c +++ b/drivers/target/target_core_spc.c @@ -784,7 +784,7 @@ static int spc_emulate_modesense(struct unsigned char *rbuf; int type = dev->transport->get_device_type(dev); int ten = (cmd->t_task_cdb[0] == MODE_SENSE_10); - int offset = ten ? 8 : 4; + u32 offset = ten ? 8 : 4; int length = 0; unsigned char buf[SE_MODE_PAGE_BUF]; @@ -817,6 +817,7 @@ static int spc_emulate_modesense(struct offset -= 2; buf[0] = (offset >> 8) & 0xff; buf[1] = offset & 0xff; + offset += 2; if ((cmd->se_lun->lun_access & TRANSPORT_LUNFLAGS_READ_ONLY) || (cmd->se_deve && @@ -826,13 +827,10 @@ static int spc_emulate_modesense(struct if ((dev->se_sub_dev->se_dev_attrib.emulate_write_cache > 0) && (dev->se_sub_dev->se_dev_attrib.emulate_fua_write > 0)) spc_modesense_dpofua(&buf[3], type); - - if ((offset + 2) > cmd->data_length) - offset = cmd->data_length; - } else { offset -= 1; buf[0] = offset & 0xff; + offset += 1; if ((cmd->se_lun->lun_access & TRANSPORT_LUNFLAGS_READ_ONLY) || (cmd->se_deve && @@ -842,14 +840,13 @@ static int spc_emulate_modesense(struct if ((dev->se_sub_dev->se_dev_attrib.emulate_write_cache > 0) && (dev->se_sub_dev->se_dev_attrib.emulate_fua_write > 0)) spc_modesense_dpofua(&buf[2], type); - - if ((offset + 1) > cmd->data_length) - offset = cmd->data_length; } rbuf = transport_kmap_data_sg(cmd); - memcpy(rbuf, buf, offset); - transport_kunmap_data_sg(cmd); + if (rbuf) { + memcpy(rbuf, buf, min(offset, cmd->data_length)); + transport_kunmap_data_sg(cmd); + } target_complete_cmd(cmd, GOOD); return 0; -- 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/