diff options
author | Daniel Vetter <daniel.vetter@ffwll.ch> | 2021-02-22 13:06:43 +0300 |
---|---|---|
committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2021-03-17 18:34:30 +0300 |
commit | beefac3c93bcc67208bad9f5e851204a7d7682b6 (patch) | |
tree | 93a15c504622eecba7f16bccca950b68abeddc46 | |
parent | 87515f38983d913cf196f0fadf2bef7f9dd4f84e (diff) | |
download | linux-beefac3c93bcc67208bad9f5e851204a7d7682b6.tar.xz |
drm/compat: Clear bounce structures
commit de066e116306baf3a6a62691ac63cfc0b1dabddb upstream.
Some of them have gaps, or fields we don't clear. Native ioctl code
does full copies plus zero-extends on size mismatch, so nothing can
leak. But compat is more hand-rolled so need to be careful.
None of these matter for performance, so just memset.
Also I didn't fix up the CONFIG_DRM_LEGACY or CONFIG_DRM_AGP ioctl, those
are security holes anyway.
Acked-by: Maxime Ripard <mripard@kernel.org>
Reported-by: syzbot+620cf21140fc7e772a5d@syzkaller.appspotmail.com # vblank ioctl
Cc: syzbot+620cf21140fc7e772a5d@syzkaller.appspotmail.com
Cc: stable@vger.kernel.org
Signed-off-by: Daniel Vetter <daniel.vetter@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20210222100643.400935-1-daniel.vetter@ffwll.ch
(cherry picked from commit e926c474ebee404441c838d18224cd6f246a71b7)
Signed-off-by: Maarten Lankhorst <maarten.lankhorst@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
-rw-r--r-- | drivers/gpu/drm/drm_ioc32.c | 11 |
1 files changed, 11 insertions, 0 deletions
diff --git a/drivers/gpu/drm/drm_ioc32.c b/drivers/gpu/drm/drm_ioc32.c index bfeeb6a56135..86105e7f07fc 100644 --- a/drivers/gpu/drm/drm_ioc32.c +++ b/drivers/gpu/drm/drm_ioc32.c @@ -96,6 +96,8 @@ static int compat_drm_version(struct file *file, unsigned int cmd, if (copy_from_user(&v32, (void __user *)arg, sizeof(v32))) return -EFAULT; + memset(&v, 0, sizeof(v)); + v = (struct drm_version) { .name_len = v32.name_len, .name = compat_ptr(v32.name), @@ -134,6 +136,9 @@ static int compat_drm_getunique(struct file *file, unsigned int cmd, if (copy_from_user(&uq32, (void __user *)arg, sizeof(uq32))) return -EFAULT; + + memset(&uq, 0, sizeof(uq)); + uq = (struct drm_unique){ .unique_len = uq32.unique_len, .unique = compat_ptr(uq32.unique), @@ -260,6 +265,8 @@ static int compat_drm_getclient(struct file *file, unsigned int cmd, if (copy_from_user(&c32, argp, sizeof(c32))) return -EFAULT; + memset(&client, 0, sizeof(client)); + client.idx = c32.idx; err = drm_ioctl_kernel(file, drm_getclient, &client, DRM_UNLOCKED); @@ -842,6 +849,8 @@ static int compat_drm_wait_vblank(struct file *file, unsigned int cmd, if (copy_from_user(&req32, argp, sizeof(req32))) return -EFAULT; + memset(&req, 0, sizeof(req)); + req.request.type = req32.request.type; req.request.sequence = req32.request.sequence; req.request.signal = req32.request.signal; @@ -879,6 +888,8 @@ static int compat_drm_mode_addfb2(struct file *file, unsigned int cmd, struct drm_mode_fb_cmd2 req64; int err; + memset(&req64, 0, sizeof(req64)); + if (copy_from_user(&req64, argp, offsetof(drm_mode_fb_cmd232_t, modifier))) return -EFAULT; |