diff options
| author | Dan Carpenter <dan.carpenter@oracle.com> | 2020-01-13 14:08:14 +0300 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2020-04-24 07:59:14 +0200 |
| commit | 14d59995ffbb4b42ecb1e9fcf5e329cfcbd81615 (patch) | |
| tree | d8759e78631ac023a1fed400d04bd0c6a32087a8 | |
| parent | a42a984c7b0cf8ceab08c0ff581d474d9657b5a7 (diff) | |
fbdev: potential information leak in do_fb_ioctl()
commit d3d19d6fc5736a798b118971935ce274f7deaa82 upstream.
The "fix" struct has a 2 byte hole after ->ywrapstep and the
"fix = info->fix;" assignment doesn't necessarily clear it. It depends
on the compiler. The solution is just to replace the assignment with an
memcpy().
Fixes: 1f5e31d7e55a ("fbmem: don't call copy_from/to_user() with mutex held")
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: "Eric W. Biederman" <ebiederm@xmission.com>
Cc: Andrea Righi <righi.andrea@gmail.com>
Cc: Daniel Vetter <daniel.vetter@ffwll.ch>
Cc: Sam Ravnborg <sam@ravnborg.org>
Cc: Maarten Lankhorst <maarten.lankhorst@linux.intel.com>
Cc: Daniel Thompson <daniel.thompson@linaro.org>
Cc: Peter Rosin <peda@axentia.se>
Cc: Jani Nikula <jani.nikula@intel.com>
Cc: Gerd Hoffmann <kraxel@redhat.com>
Signed-off-by: Bartlomiej Zolnierkiewicz <b.zolnierkie@samsung.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20200113100132.ixpaymordi24n3av@kili.mountain
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
| -rw-r--r-- | drivers/video/fbdev/core/fbmem.c | 2 |
1 files changed, 1 insertions, 1 deletions
diff --git a/drivers/video/fbdev/core/fbmem.c b/drivers/video/fbdev/core/fbmem.c index c928190666ac..ae623cd04d6c 100644 --- a/drivers/video/fbdev/core/fbmem.c +++ b/drivers/video/fbdev/core/fbmem.c @@ -1132,7 +1132,7 @@ static long do_fb_ioctl(struct fb_info *info, unsigned int cmd, case FBIOGET_FSCREENINFO: if (!lock_fb_info(info)) return -ENODEV; - fix = info->fix; + memcpy(&fix, &info->fix, sizeof(fix)); unlock_fb_info(info); ret = copy_to_user(argp, &fix, sizeof(fix)) ? -EFAULT : 0; |