diff options
| author | Daniel Vetter <daniel.vetter@ffwll.ch> | 2018-12-20 18:13:53 +0100 |
|---|---|---|
| committer | Daniel Vetter <daniel.vetter@ffwll.ch> | 2018-12-20 18:13:53 +0100 |
| commit | b6aac625e579ca684448f8ace632f8dceb972afb (patch) | |
| tree | 6ea8716b486fbe05a8b12de38d9ed814fcdbb1b3 | |
| parent | 7566ec393f4161572ba6f11ad5171fd5d59b0fbd (diff) | |
| parent | 505b5240329b922f21f91d5b5d1e535c805eca6d (diff) | |
Merge tag 'drm-misc-fixes-2018-12-20' of git://anongit.freedesktop.org/drm/drm-misc into drm-fixesdrm-fixes-2018-12-21
Fix spectre v1 vuln in drm_ioctl
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
From: Sean Paul <sean@poorly.run>
Link: https://patchwork.freedesktop.org/patch/msgid/20181220165740.GA42344@art_vandelay
| -rw-r--r-- | drivers/gpu/drm/drm_ioctl.c | 10 |
1 files changed, 8 insertions, 2 deletions
diff --git a/drivers/gpu/drm/drm_ioctl.c b/drivers/gpu/drm/drm_ioctl.c index 94bd872d56c4..7e6746b2d704 100644 --- a/drivers/gpu/drm/drm_ioctl.c +++ b/drivers/gpu/drm/drm_ioctl.c @@ -37,6 +37,7 @@ #include <linux/pci.h> #include <linux/export.h> +#include <linux/nospec.h> /** * DOC: getunique and setversion story @@ -800,13 +801,17 @@ long drm_ioctl(struct file *filp, if (is_driver_ioctl) { /* driver ioctl */ - if (nr - DRM_COMMAND_BASE >= dev->driver->num_ioctls) + unsigned int index = nr - DRM_COMMAND_BASE; + + if (index >= dev->driver->num_ioctls) goto err_i1; - ioctl = &dev->driver->ioctls[nr - DRM_COMMAND_BASE]; + index = array_index_nospec(index, dev->driver->num_ioctls); + ioctl = &dev->driver->ioctls[index]; } else { /* core ioctl */ if (nr >= DRM_CORE_IOCTL_COUNT) goto err_i1; + nr = array_index_nospec(nr, DRM_CORE_IOCTL_COUNT); ioctl = &drm_ioctls[nr]; } @@ -888,6 +893,7 @@ bool drm_ioctl_flags(unsigned int nr, unsigned int *flags) if (nr >= DRM_CORE_IOCTL_COUNT) return false; + nr = array_index_nospec(nr, DRM_CORE_IOCTL_COUNT); *flags = drm_ioctls[nr].flags; return true; |