From mboxrd@z Thu Jan 1 00:00:00 1970 From: "Stephen M. Cameron" Subject: [PATCH 13/13] hpsa: defend against zero sized buffers in passthru ioctls Date: Fri, 08 Oct 2010 15:07:08 -0500 Message-ID: <20101008200708.24279.8723.stgit@beardog.cce.hp.com> References: <20101008200453.24279.6638.stgit@beardog.cce.hp.com> Mime-Version: 1.0 Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: 7bit Return-path: In-Reply-To: <20101008200453.24279.6638.stgit@beardog.cce.hp.com> Sender: linux-kernel-owner@vger.kernel.org To: axboe@kernel.dk, James.Bottomley@HansenPartnership.com Cc: akpm@linux-foundation.org, thenzl@redhat.com, mike.miller@hp.com, linux-scsi@vger.kernel.org, linux-kernel@vger.kernel.org List-Id: linux-scsi@vger.kernel.org From: Stephen M. Cameron Signed-off-by: Stephen M. Cameron --- drivers/scsi/hpsa.c | 36 ++++++++++++++++-------------------- 1 files changed, 16 insertions(+), 20 deletions(-) diff --git a/drivers/scsi/hpsa.c b/drivers/scsi/hpsa.c index c36427d..cba5bf4 100644 --- a/drivers/scsi/hpsa.c +++ b/drivers/scsi/hpsa.c @@ -2458,15 +2458,17 @@ static int hpsa_passthru_ioctl(struct ctlr_info *h, void __user *argp) buff = kmalloc(iocommand.buf_size, GFP_KERNEL); if (buff == NULL) return -EFAULT; - } - if (iocommand.Request.Type.Direction == XFER_WRITE) { - /* Copy the data into the buffer we created */ - if (copy_from_user(buff, iocommand.buf, iocommand.buf_size)) { - kfree(buff); - return -EFAULT; + if (iocommand.Request.Type.Direction == XFER_WRITE) { + /* Copy the data into the buffer we created */ + if (copy_from_user(buff, iocommand.buf, + iocommand.buf_size)) { + kfree(buff); + return -EFAULT; + } + } else { + memset(buff, 0, iocommand.buf_size); } - } else - memset(buff, 0, iocommand.buf_size); + } c = cmd_special_alloc(h); if (c == NULL) { kfree(buff); @@ -2512,8 +2514,8 @@ static int hpsa_passthru_ioctl(struct ctlr_info *h, void __user *argp) cmd_special_free(h, c); return -EFAULT; } - - if (iocommand.Request.Type.Direction == XFER_READ) { + if (iocommand.Request.Type.Direction == XFER_READ && + iocommand.buf_size > 0) { /* Copy the data out of the buffer we created */ if (copy_to_user(iocommand.buf, buff, iocommand.buf_size)) { kfree(buff); @@ -2606,14 +2608,7 @@ static int hpsa_big_passthru_ioctl(struct ctlr_info *h, void __user *argp) } c->cmd_type = CMD_IOCTL_PEND; c->Header.ReplyQueue = 0; - - if (ioc->buf_size > 0) { - c->Header.SGList = sg_used; - c->Header.SGTotal = sg_used; - } else { - c->Header.SGList = 0; - c->Header.SGTotal = 0; - } + c->Header.SGList = c->Header.SGTotal = sg_used; memcpy(&c->Header.LUN, &ioc->LUN_info, sizeof(c->Header.LUN)); c->Header.Tag.lower = c->busaddr; memcpy(&c->Request, &ioc->Request, sizeof(c->Request)); @@ -2630,7 +2625,8 @@ static int hpsa_big_passthru_ioctl(struct ctlr_info *h, void __user *argp) } } hpsa_scsi_do_simple_cmd_core(h, c); - hpsa_pci_unmap(h->pdev, c, sg_used, PCI_DMA_BIDIRECTIONAL); + if (sg_used) + hpsa_pci_unmap(h->pdev, c, sg_used, PCI_DMA_BIDIRECTIONAL); check_ioctl_unit_attention(h, c); /* Copy the error information out */ memcpy(&ioc->error_info, c->err_info, sizeof(ioc->error_info)); @@ -2639,7 +2635,7 @@ static int hpsa_big_passthru_ioctl(struct ctlr_info *h, void __user *argp) status = -EFAULT; goto cleanup1; } - if (ioc->Request.Type.Direction == XFER_READ) { + if (ioc->Request.Type.Direction == XFER_READ && ioc->buf_size > 0) { /* Copy the data out of the buffer we created */ BYTE __user *ptr = ioc->buf; for (i = 0; i < sg_used; i++) {