From f984579a01d85166ee7380204a96d978a67687a1 Mon Sep 17 00:00:00 2001 From: Tomas Bortoli Date: Mon, 23 Jul 2018 17:44:04 +0200 Subject: 9p: validate PDU length This commit adds length check for the PDU size. The size contained in the header has to match the actual size, except for TCP (trans_fd.c) where actual length is not known ahead and the header's length will be checked only against the validity range. Link: http://lkml.kernel.org/r/20180723154404.2406-1-tomasbortoli@gmail.com Signed-off-by: Tomas Bortoli Reported-by: syzbot+65c6b72f284a39d416b4@syzkaller.appspotmail.com To: Eric Van Hensbergen To: Ron Minnich To: Latchesar Ionkov Cc: David S. Miller Signed-off-by: Dominique Martinet --- net/9p/trans_fd.c | 5 ++++- 1 file changed, 4 insertions(+), 1 deletion(-) (limited to 'net/9p/trans_fd.c') diff --git a/net/9p/trans_fd.c b/net/9p/trans_fd.c index cce41b20a709..964260265b13 100644 --- a/net/9p/trans_fd.c +++ b/net/9p/trans_fd.c @@ -325,7 +325,9 @@ static void p9_read_work(struct work_struct *work) if ((!m->req) && (m->rc.offset == m->rc.capacity)) { p9_debug(P9_DEBUG_TRANS, "got new header\n"); - err = p9_parse_header(&m->rc, NULL, NULL, NULL, 0); + /* Header size */ + m->rc.size = 7; + err = p9_parse_header(&m->rc, &m->rc.size, NULL, NULL, 0); if (err) { p9_debug(P9_DEBUG_ERROR, "error parsing header: %d\n", err); @@ -370,6 +372,7 @@ static void p9_read_work(struct work_struct *work) */ if ((m->req) && (m->rc.offset == m->rc.capacity)) { p9_debug(P9_DEBUG_TRANS, "got new packet\n"); + m->req->rc->size = m->rc.offset; spin_lock(&m->client->lock); if (m->req->status != REQ_STATUS_ERROR) status = REQ_STATUS_RCVD; -- cgit v1.2.3-70-g09d2