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-next>] [day] [month] [year] [list]
Message-ID: <20140827185651.29388.16082.stgit@gimli.home>
Date:	Wed, 27 Aug 2014 12:57:33 -0600
From:	Alex Williamson <alex.williamson@...hat.com>
To:	airlied@...ux.ie, dri-devel@...ts.freedesktop.org
Cc:	linux-kernel@...r.kernel.org, alex.williamson@...hat.com
Subject: [PATCH] drm: Test for PCI root bus to avoid NULL pointer dereference

If we have a GPU on the PCI root bus that calls
drm_pcie_get_speed_cap_mask() we end up with a NULL pointer
dereference since pdev->bus->self is NULL.  We already protect
against callers passing non-PCI devices, so let's also catch this
case and return -EINVAL.

Root complex graphics are not terribly likely outside of IGD, but
when we assign a standard plugin GPU to a virtual machine, our
assumption that we have a parent device quickly becomes invalid.

Signed-off-by: Alex Williamson <alex.williamson@...hat.com>
---

 drivers/gpu/drm/drm_pci.c |    2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/gpu/drm/drm_pci.c b/drivers/gpu/drm/drm_pci.c
index 020cfd9..411e806 100644
--- a/drivers/gpu/drm/drm_pci.c
+++ b/drivers/gpu/drm/drm_pci.c
@@ -390,7 +390,7 @@ int drm_pcie_get_speed_cap_mask(struct drm_device *dev, u32 *mask)
 	u32 lnkcap, lnkcap2;
 
 	*mask = 0;
-	if (!dev->pdev)
+	if (!dev->pdev || pci_is_root_bus(dev->pdev->bus))
 		return -EINVAL;
 
 	root = dev->pdev->bus->self;

--
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