From db042925a5ab7a550b710addeadbf6f72e3a8a4b Mon Sep 17 00:00:00 2001 From: zhang jiao Date: Wed, 10 Sep 2025 17:17:38 +0800 Subject: [PATCH] vhost: vringh: Modify the return value check [ Upstream commit 82a8d0fda55b35361ee7f35b54fa2b66d7847d2b ] The return value of copy_from_iter and copy_to_iter can't be negative, check whether the copied lengths are equal. Fixes: 309bba39c945 ("vringh: iterate on iotlb_translate to handle large translations") Cc: "Stefano Garzarella" Signed-off-by: zhang jiao Message-Id: <20250910091739.2999-1-zhangjiao2@cmss.chinamobile.com> Signed-off-by: Michael S. Tsirkin Signed-off-by: Sasha Levin --- 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 c570d214d5b68..d89c2bce94cbf 100644 --- a/drivers/vhost/vringh.c +++ b/drivers/vhost/vringh.c @@ -1162,6 +1162,7 @@ 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, @@ -1173,9 +1174,9 @@ static inline int copy_from_iotlb(const struct vringh *vrh, void *dst, iov_iter_bvec(&iter, ITER_SOURCE, iov, ret, 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; -- 2.47.3