From cf3aa02cb4a0c5af5557dd47f15a08a7df33182a Mon Sep 17 00:00:00 2001 From: "J. Bruce Fields" Date: Wed, 26 Jun 2013 11:09:06 -0400 Subject: [PATCH] svcrpc: fix handling of too-short rpc's If we detect that an rpc is too short, we abort and close the connection. Except, there's a bug here: we're leaving sk_datalen nonzero without leaving any pages in the sk_pages array. The most likely result of the inconsistency is a subsequent crash in svc_tcp_clear_pages. Also demote the BUG_ON in svc_tcp_clear_pages to a WARN. Cc: stable@kernel.org Signed-off-by: J. Bruce Fields --- net/sunrpc/svcsock.c | 9 +++++++-- 1 file changed, 7 insertions(+), 2 deletions(-) diff --git a/net/sunrpc/svcsock.c b/net/sunrpc/svcsock.c index 0f679df7d072..df74919c81c0 100644 --- a/net/sunrpc/svcsock.c +++ b/net/sunrpc/svcsock.c @@ -917,7 +917,10 @@ static void svc_tcp_clear_pages(struct svc_sock *svsk) len = svsk->sk_datalen; npages = (len + PAGE_SIZE - 1) >> PAGE_SHIFT; for (i = 0; i < npages; i++) { - BUG_ON(svsk->sk_pages[i] == NULL); + if (svsk->sk_pages[i] == NULL) { + WARN_ON_ONCE(1); + continue; + } put_page(svsk->sk_pages[i]); svsk->sk_pages[i] = NULL; } @@ -1092,8 +1095,10 @@ static int svc_tcp_recvfrom(struct svc_rqst *rqstp) goto err_noclose; } - if (svc_sock_reclen(svsk) < 8) + if (svc_sock_reclen(svsk) < 8) { + svsk->sk_datalen = 0; goto err_delete; /* client is nuts. */ + } rqstp->rq_arg.len = svsk->sk_datalen; rqstp->rq_arg.page_base = 0; -- 2.20.1