This is a note to let you know that I've just added the patch titled drm: Prevent overwriting from userspace underallocating core ioctl structs to the 3.4-stable tree which can be found at: http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary The filename of the patch is: drm-prevent-overwriting-from-userspace-underallocating-core-ioctl-structs.patch and it can be found in the queue-3.4 subdirectory. If you, or anyone else, feels it should not be added to the stable tree, please let <stable@xxxxxxxxxxxxxxx> know about it. >From b062672e305ce071f21eb9e18b102c2a430e0999 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 From: Chris Wilson <chris@xxxxxxxxxxxxxxxxxx> 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: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> --- drivers/gpu/drm/drm_drv.c | 9 ++++++++- 1 file changed, 8 insertions(+), 1 deletion(-) --- a/drivers/gpu/drm/drm_drv.c +++ b/drivers/gpu/drm/drm_drv.c @@ -420,9 +420,16 @@ 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; Patches currently in stable-queue which might be from chris@xxxxxxxxxxxxxxxxxx are queue-3.4/drm-prevent-overwriting-from-userspace-underallocating-core-ioctl-structs.patch -- To unsubscribe from this list: send the line "unsubscribe stable" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html