From: Dan Aloni <dan@kernelim.com>
Date: Fri, 2 Oct 2020 19:33:43 +0000 (+0300)
Subject: svcrdma: fix bounce buffers for unaligned offsets and multiple pages
X-Git-Tag: v5.4.73~131
X-Git-Url: https://www.infradead.org/git/?a=commitdiff_plain;h=9c27185e12e8c2317e5b1507fdf9c23a99d39c7a;p=users%2Fdwmw2%2Flinux.git

svcrdma: fix bounce buffers for unaligned offsets and multiple pages

[ Upstream commit c327a310ec4d6ecbea13185ed56c11def441d9ab ]

This was discovered using O_DIRECT at the client side, with small
unaligned file offsets or IOs that span multiple file pages.

Fixes: e248aa7be86 ("svcrdma: Remove max_sge check at connect time")
Signed-off-by: Dan Aloni <dan@kernelim.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---

diff --git a/net/sunrpc/xprtrdma/svc_rdma_sendto.c b/net/sunrpc/xprtrdma/svc_rdma_sendto.c
index 217106c66a13c..25e8922c10b28 100644
--- a/net/sunrpc/xprtrdma/svc_rdma_sendto.c
+++ b/net/sunrpc/xprtrdma/svc_rdma_sendto.c
@@ -609,10 +609,11 @@ static int svc_rdma_pull_up_reply_msg(struct svcxprt_rdma *rdma,
 		while (remaining) {
 			len = min_t(u32, PAGE_SIZE - pageoff, remaining);
 
-			memcpy(dst, page_address(*ppages), len);
+			memcpy(dst, page_address(*ppages) + pageoff, len);
 			remaining -= len;
 			dst += len;
 			pageoff = 0;
+			ppages++;
 		}
 	}