Description
Integer signedness error in the drm_modeset_ctl function in (1) drivers/gpu/drm/drm_irq.c in the Direct Rendering Manager (DRM) subsystem in the Linux kernel before 2.6.38 and (2) sys/dev/pci/drm/drm_irq.c in the kernel in OpenBSD before 4.9 allows local users to trigger out-of-bounds write operations, and consequently cause a denial of service (system crash) or possibly have unspecified other impact, via a crafted num_crtcs (aka vb_num) structure member in an ioctl argument.
Fixed in Linux distributions
Distributions backport fixes, so the version that fixes this vulnerability differs per release — upgrade to at least the version shown. From the distributions' security trackers and advisories.
Red Hat
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| RHEL 6 | perf +13 | 2.6.32-71.29.1.el6 | RHSA-2011:0498 |
Show 1 more (older releases, extended support, other products)Fewer releases
| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Red Hat MRG 1 | perf +10 | 2.6.33.9-rt31.64.el5rt | RHSA-2011:0500 |
Advisories 2
- RHSA-2011:0500 Red Hat Security Advisory: kernel-rt security and bug fix update Red Hat Security Advisories (RHSA) · Jun 28, 2026
- RHSA-2011:0498 Red Hat Security Advisory: kernel security, bug fix, and enhancement update Red Hat Security Advisories (RHSA) · Jun 28, 2026
References
- kernel-drmioctl-priv-escalation(67199) vdb-entry
- 47639 vdb-entry
- https://bugzilla.redhat.com/show_bug.cgi?id=679925
- http://www.openbsd.org/cgi-bin/cvsweb/src/sys/dev/pci/drm/drm_irq.c.diff?r1=1.41%3Br2=1.42%3Bf=h
- http://www.openbsd.org/cgi-bin/cvsweb/src/sys/dev/pci/drm/drm_irq.c
- http://www.kernel.org/pub/linux/kernel/v2.6/ChangeLog-2.6.38
- http://git.kernel.org/?p=linux/kernel/git/torvalds/linux-2.6.git%3Ba=commit%3Bh=1922756124ddd53846877416d92ba4a802bc658f