From: Dan Carpenter dan.carpenter@oracle.com
[ Upstream commit 74b67efa8d7b4f90137f0ab9a80dd319da050350 ]
The copy_from_user() function returns the number of bytes remaining to be copied but we want to return a negative error code. Otherwise the callers treat it as a successful copy.
Signed-off-by: Dan Carpenter dan.carpenter@oracle.com Signed-off-by: Sean Paul seanpaul@chromium.org Link: https://patchwork.freedesktop.org/patch/msgid/20190618131843.GA29463@mwanda Signed-off-by: Sasha Levin sashal@kernel.org --- drivers/gpu/drm/drm_bufs.c | 5 ++++- drivers/gpu/drm/drm_ioc32.c | 5 ++++- 2 files changed, 8 insertions(+), 2 deletions(-)
diff --git a/drivers/gpu/drm/drm_bufs.c b/drivers/gpu/drm/drm_bufs.c index 0f05b8d8fefa..b829fde80f7b 100644 --- a/drivers/gpu/drm/drm_bufs.c +++ b/drivers/gpu/drm/drm_bufs.c @@ -1321,7 +1321,10 @@ static int copy_one_buf(void *data, int count, struct drm_buf_entry *from) .size = from->buf_size, .low_mark = from->low_mark, .high_mark = from->high_mark}; - return copy_to_user(to, &v, offsetof(struct drm_buf_desc, flags)); + + if (copy_to_user(to, &v, offsetof(struct drm_buf_desc, flags))) + return -EFAULT; + return 0; }
int drm_legacy_infobufs(struct drm_device *dev, void *data, diff --git a/drivers/gpu/drm/drm_ioc32.c b/drivers/gpu/drm/drm_ioc32.c index f8e96e648acf..bfeeb6a56135 100644 --- a/drivers/gpu/drm/drm_ioc32.c +++ b/drivers/gpu/drm/drm_ioc32.c @@ -372,7 +372,10 @@ static int copy_one_buf32(void *data, int count, struct drm_buf_entry *from) .size = from->buf_size, .low_mark = from->low_mark, .high_mark = from->high_mark}; - return copy_to_user(to + count, &v, offsetof(drm_buf_desc32_t, flags)); + + if (copy_to_user(to + count, &v, offsetof(drm_buf_desc32_t, flags))) + return -EFAULT; + return 0; }
static int drm_legacy_infobufs32(struct drm_device *dev, void *data,