From: Michael S. Tsirkin Date: Tue, 23 Sep 2025 21:44:26 +0000 (-0400) Subject: vhost: vringh: Fix copy_to_iter return value check X-Git-Url: https://www.infradead.org/git/?a=commitdiff_plain;h=c0e1116189acfec74c8f5032da257b954d3f757f;p=users%2Fhch%2Fmisc.git vhost: vringh: Fix copy_to_iter return value check The return value of copy_to_iter can't be negative, check whether the copied length is equal to the requested length instead of checking for negative values. Fixes: 309bba39c945 ("vringh: iterate on iotlb_translate to handle large translations") Cc: "Stefano Garzarella" Cc: zhang jiao Link: https://lore.kernel.org/all/20250910091739.2999-1-zhangjiao2@cmss.chinamobile.com Message-ID: Signed-off-by: Michael S. Tsirkin --- diff --git a/drivers/vhost/vringh.c b/drivers/vhost/vringh.c index 0c8a17cbb22e..925858cc6096 100644 --- a/drivers/vhost/vringh.c +++ b/drivers/vhost/vringh.c @@ -1162,6 +1162,7 @@ static inline int copy_to_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)dst, len - total_translated, &translated, @@ -1179,9 +1180,9 @@ static inline int copy_to_iotlb(const struct vringh *vrh, void *dst, translated); } - ret = copy_to_iter(src, translated, &iter); - if (ret < 0) - return ret; + size = copy_to_iter(src, translated, &iter); + if (size != translated) + return -EFAULT; src += translated; dst += translated;