svcrpc: fix handling of too-short rpc's

commit cf3aa02cb4a0c5af5557dd47f15a08a7df33182a upstream.

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.

Signed-off-by: J. Bruce Fields <bfields@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This commit is contained in:
J. Bruce Fields 2013-06-26 11:09:06 -04:00 committed by Greg Kroah-Hartman
parent c814208bb3
commit 57370589c1
1 changed files with 7 additions and 2 deletions

View File

@ -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;