Re: [PATCH] vhost: vringh: Modify the return value check

From: zhang jiao <redacted>

The return value of copy_from_iter and copy_to_iter can't be negative,
check whether the copied lengths are equal.

Signed-off-by: zhang jiao <redacted>
---
 drivers/vhost/vringh.c | 7 ++++---
 1 file changed, 4 insertions(+), 3 deletions(-)

diff --git a/drivers/vhost/vringh.c b/drivers/vhost/vringh.c
index 9f27c3f6091b..0c8a17cbb22e 100644
--- a/drivers/vhost/vringh.c
+++ b/drivers/vhost/vringh.c

@@ -1115,6 +1115,7 @@ static inline int copy_from_iotlb(const struct vringh *vrh, void *dst,
                struct iov_iter iter;
                u64 translated;
                int ret;
+               size_t size;

                ret = iotlb_translate(vrh, (u64)(uintptr_t)src,
                                      len - total_translated, &translated,

@@ -1132,9 +1133,9 @@ static inline int copy_from_iotlb(const struct vringh *vrh, void *dst,
                                      translated);
                }

-               ret = copy_from_iter(dst, translated, &iter);
-               if (ret < 0)
-                       return ret;
+               size = copy_from_iter(dst, translated, &iter);
+               if (size != translated)
+                       return -EFAULT;

                src += translated;
                dst += translated;
--

2.33.0