lists.openwall.net   lists  /  announce  owl-users  owl-dev  john-users  john-dev  passwdqc-users  yescrypt  popa3d-users  /  oss-security  kernel-hardening  musl  sabotage  tlsify  passwords  /  crypt-dev  xvendor  /  Bugtraq  Full-Disclosure  linux-kernel  linux-netdev  linux-ext4  linux-hardening  linux-cve-announce  PHC 
Open Source and information security mailing list archives
 
Hash Suite: Windows password security audit tool. GUI, reports in PDF.
[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]
Message-ID: <1391630568-49251-137-git-send-email-paul.gortmaker@windriver.com>
Date:	Wed, 5 Feb 2014 15:01:31 -0500
From:	Paul Gortmaker <paul.gortmaker@...driver.com>
To:	<stable@...r.kernel.org>, <linux-kernel@...r.kernel.org>
CC:	Matthew Garrett <mjg@...hat.com>,
	Sarah Sharp <sarah.a.sharp@...ux.intel.com>,
	Paul Gortmaker <paul.gortmaker@...driver.com>
Subject: [v2.6.34-stable 136/213] xhci: Make handover code more robust

From: Matthew Garrett <mjg@...hat.com>

                   -------------------
    This is a commit scheduled for the next v2.6.34 longterm release.
    http://git.kernel.org/?p=linux/kernel/git/paulg/longterm-queue-2.6.34.git
    If you see a problem with using this for longterm, please comment.
                   -------------------

commit e955a1cd086de4d165ae0f4c7be7289d84b63bdc upstream.

My test platform (Intel DX79SI) boots reliably under BIOS, but frequently
crashes when booting via UEFI. I finally tracked this down to the xhci
handoff code. It seems that reads from the device occasionally just return
0xff, resulting in xhci_find_next_cap_offset generating a value that's
larger than the resource region. We then oops when attempting to read the
value. Sanity checking that value lets us avoid the crash.

I've no idea what's causing the underlying problem, and xhci still doesn't
actually *work* even with this, but the machine at least boots which will
probably make further debugging easier.

This should be backported to kernels as old as 2.6.31, that contain the
commit 66d4eadd8d067269ea8fead1a50fe87c2979a80d "USB: xhci: BIOS handoff
and HW initialization."

Signed-off-by: Matthew Garrett <mjg@...hat.com>
Signed-off-by: Sarah Sharp <sarah.a.sharp@...ux.intel.com>
Signed-off-by: Paul Gortmaker <paul.gortmaker@...driver.com>
---
 drivers/usb/host/pci-quirks.c | 12 ++++++++++--
 1 file changed, 10 insertions(+), 2 deletions(-)

diff --git a/drivers/usb/host/pci-quirks.c b/drivers/usb/host/pci-quirks.c
index eae8b18437cb..bfbc6b97eb8f 100644
--- a/drivers/usb/host/pci-quirks.c
+++ b/drivers/usb/host/pci-quirks.c
@@ -418,12 +418,12 @@ static void __devinit quirk_usb_handoff_xhci(struct pci_dev *pdev)
 	void __iomem *op_reg_base;
 	u32 val;
 	int timeout;
+	int len = pci_resource_len(pdev, 0);
 
 	if (!mmio_resource_enabled(pdev, 0))
 		return;
 
-	base = ioremap_nocache(pci_resource_start(pdev, 0),
-				pci_resource_len(pdev, 0));
+	base = ioremap_nocache(pci_resource_start(pdev, 0), len);
 	if (base == NULL)
 		return;
 
@@ -433,9 +433,17 @@ static void __devinit quirk_usb_handoff_xhci(struct pci_dev *pdev)
 	 */
 	ext_cap_offset = xhci_find_next_cap_offset(base, XHCI_HCC_PARAMS_OFFSET);
 	do {
+		if ((ext_cap_offset + sizeof(val)) > len) {
+			/* We're reading garbage from the controller */
+			dev_warn(&pdev->dev,
+				 "xHCI controller failing to respond");
+			return;
+		}
+
 		if (!ext_cap_offset)
 			/* We've reached the end of the extended capabilities */
 			goto hc_init;
+
 		val = readl(base + ext_cap_offset);
 		if (XHCI_EXT_CAPS_ID(val) == XHCI_EXT_CAPS_LEGACY)
 			break;
-- 
1.8.5.2

--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/

Powered by blists - more mailing lists

Powered by Openwall GNU/*/Linux Powered by OpenVZ