svcrdma: bound check rq_pages index in inline path

[ Upstream commit d1bea0ce35b6095544ee82bb54156fc62c067e58 ]

svc_rdma_copy_inline_range indexed rqstp->rq_pages[rc_curpage] without
verifying rc_curpage stays within the allocated page array. Add guards
before the first use and after advancing to a new page.

Fixes: d7cc73972661 ("svcrdma: support multiple Read chunks per RPC")
Cc: stable@vger.kernel.org
Signed-off-by: Joshua Rogers <linux@joshua.hu>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
[ replaced rqstp->rq_maxpages with ARRAY_SIZE(rqstp->rq_pages) ]
Signed-off-by: Sasha Levin <sashal@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

diff --git a/net/sunrpc/xprtrdma/svc_rdma_rw.c b/net/sunrpc/xprtrdma/svc_rdma_rw.c
index 1452630d640c1b4469056a5b30d9877c045ef5f5..8156dc20b852fa6b8d289ad4864c915b82a34c1f 100644 (file)
--- a/net/sunrpc/xprtrdma/svc_rdma_rw.c
+++ b/net/sunrpc/xprtrdma/svc_rdma_rw.c
@@ -841,6 +841,9 @@ static int svc_rdma_copy_inline_range(struct svc_rqst *rqstp,
        for (page_no = 0; page_no < numpages; page_no++) {
                unsigned int page_len;
 
+               if (head->rc_curpage >= ARRAY_SIZE(rqstp->rq_pages))
+                       return -EINVAL;
+
                page_len = min_t(unsigned int, remaining,
                                 PAGE_SIZE - head->rc_pageoff);