linux/drivers/gpu
Gustavo A. R. Silva 505b524032 drm/ioctl: Fix Spectre v1 vulnerabilities
nr is indirectly controlled by user-space, hence leading to a
potential exploitation of the Spectre variant 1 vulnerability.

This issue was detected with the help of Smatch:

drivers/gpu/drm/drm_ioctl.c:805 drm_ioctl() warn: potential spectre issue 'dev->driver->ioctls' [r]
drivers/gpu/drm/drm_ioctl.c:810 drm_ioctl() warn: potential spectre issue 'drm_ioctls' [r] (local cap)
drivers/gpu/drm/drm_ioctl.c:892 drm_ioctl_flags() warn: potential spectre issue 'drm_ioctls' [r] (local cap)

Fix this by sanitizing nr before using it to index dev->driver->ioctls
and drm_ioctls.

Notice that given that speculation windows are large, the policy is
to kill the speculation on the first load and not worry if it can be
completed with a dependent load/store [1].

[1] https://marc.info/?l=linux-kernel&m=152449131114778&w=2

Cc: stable@vger.kernel.org
Signed-off-by: Gustavo A. R. Silva <gustavo@embeddedor.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Link: https://patchwork.freedesktop.org/patch/msgid/20181220000015.GA18973@embeddedor
2018-12-20 08:13:29 +01:00
..
drm drm/ioctl: Fix Spectre v1 vulnerabilities 2018-12-20 08:13:29 +01:00
host1x gpu: host1x: Detach Host1x from IOMMU DMA domain on arm32 2018-09-26 17:11:14 +02:00
ipu-v3 media: v4l: mediabus: Recognise CSI-2 D-PHY and C-PHY 2018-10-04 16:06:15 -04:00
vga vga_switcheroo: Fix missing gpu_bound call at audio client registration 2018-11-05 14:56:21 +01:00
Makefile