From 91c427ac3a61ccabae0fdef53563edf40394b6c9 Mon Sep 17 00:00:00 2001 From: Jeff Layton Date: Fri, 4 May 2012 11:44:12 -0400 Subject: sunrpc: do array overrun check in svc_recv before allocating pages There's little point in waiting until after we allocate all of the pages to see if we're going to overrun the array. In the event that this calculation is really off we could end up scribbling over a bunch of memory and make it tougher to debug. Signed-off-by: Jeff Layton Signed-off-by: J. Bruce Fields --- net/sunrpc/svc_xprt.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) (limited to 'net/sunrpc') diff --git a/net/sunrpc/svc_xprt.c b/net/sunrpc/svc_xprt.c index 4bda09d..8195c6a 100644 --- a/net/sunrpc/svc_xprt.c +++ b/net/sunrpc/svc_xprt.c @@ -601,6 +601,7 @@ int svc_recv(struct svc_rqst *rqstp, long timeout) /* now allocate needed pages. If we get a failure, sleep briefly */ pages = (serv->sv_max_mesg + PAGE_SIZE) / PAGE_SIZE; + BUG_ON(pages >= RPCSVC_MAXPAGES); for (i = 0; i < pages ; i++) while (rqstp->rq_pages[i] == NULL) { struct page *p = alloc_page(GFP_KERNEL); @@ -615,7 +616,6 @@ int svc_recv(struct svc_rqst *rqstp, long timeout) rqstp->rq_pages[i] = p; } rqstp->rq_pages[i++] = NULL; /* this might be seen in nfs_read_actor */ - BUG_ON(pages >= RPCSVC_MAXPAGES); /* Make arg->head point to first page and arg->pages point to rest */ arg = &rqstp->rq_arg; -- cgit v1.1