This is a note to let you know that I have just added a patch titled drm: Prevent overwriting from userspace underallocating core ioctl to the linux-3.8.y-queue branch of the 3.8.y.z extended stable tree which can be found at: http://kernel.ubuntu.com/git?p=ubuntu/linux.git;a=shortlog;h=refs/heads/linux-3.8.y-queue This patch is scheduled to be released in version 3.8.13.13. If you, or anyone else, feels it should not be added to this tree, please reply to this email. For more information about the 3.8.y.z tree, see https://wiki.ubuntu.com/Kernel/Dev/ExtendedStable Thanks. -Kamal ------ >From 95e3ee2e369592d92a2d67da82b855907e4f9898 Mon Sep 17 00:00:00 2001 From: Chris Wilson <chris@xxxxxxxxxxxxxxxxxx> Date: Wed, 16 Oct 2013 11:22:44 +0100 Subject: drm: Prevent overwriting from userspace underallocating core ioctl structs MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit commit b062672e305ce071f21eb9e18b102c2a430e0999 upstream. Apply the protections from commit 1b2f1489633888d4a06028315dc19d65768a1c05 Author: Dave Airlie <airlied@xxxxxxxxxx> Date: Sat Aug 14 20:20:34 2010 +1000 drm: block userspace under allocating buffer and having drivers overwrite it (v2) to the core ioctl structs as well, for we found one instance where there is a 32-/64-bit size mismatch and were guilty of writing beyond the end of the user's buffer. Signed-off-by: Chris Wilson <chris@xxxxxxxxxxxxxxxxxx> Cc: Dave Airlie <airlied@xxxxxxxxxx> Reviewed-by: Ville Syrjälä <ville.syrjala@xxxxxxxxxxxxxxx> Cc: dri-devel@xxxxxxxxxxxxxxxxxxxxx Signed-off-by: Dave Airlie <airlied@xxxxxxxxxx> Signed-off-by: Kamal Mostafa <kamal@xxxxxxxxxxxxx> --- drivers/gpu/drm/drm_drv.c | 9 ++++++++- 1 file changed, 8 insertions(+), 1 deletion(-) diff --git a/drivers/gpu/drm/drm_drv.c b/drivers/gpu/drm/drm_drv.c index be174ca..4177780 100644 --- a/drivers/gpu/drm/drm_drv.c +++ b/drivers/gpu/drm/drm_drv.c @@ -411,9 +411,16 @@ long drm_ioctl(struct file *filp, asize = drv_size; } else if ((nr >= DRM_COMMAND_END) || (nr < DRM_COMMAND_BASE)) { + u32 drv_size; + ioctl = &drm_ioctls[nr]; - cmd = ioctl->cmd; + + drv_size = _IOC_SIZE(ioctl->cmd); usize = asize = _IOC_SIZE(cmd); + if (drv_size > asize) + asize = drv_size; + + cmd = ioctl->cmd; } else goto err_i1; -- 1.8.1.2 _______________________________________________ dri-devel mailing list dri-devel@xxxxxxxxxxxxxxxxxxxxx http://lists.freedesktop.org/mailman/listinfo/dri-devel