From 22dccc5454a39427de7b87a080d026b6bf66a7b9 Mon Sep 17 00:00:00 2001 From: Jim Foraker Date: Tue, 1 Nov 2016 13:44:12 -0700 Subject: [PATCH] IB/rdmavt: Only put mmap_info ref if it exists rvt_create_qp() creates qp->ip only when a qp creation request comes from userspace (udata is not NULL). If we exceed the number of available queue pairs however, the error path always attempts to put a kref to this structure. If the requestor is inside the kernel, this leads to a crash. We fix this by checking that qp->ip is not NULL before caling kref_put(). Signed-off-by: Jim Foraker Acked-by: Dennis Dalessandro Acked-by: Jonathan Toppins Acked-by: Alex Estrin Signed-off-by: Doug Ledford --- drivers/infiniband/sw/rdmavt/qp.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) diff --git a/drivers/infiniband/sw/rdmavt/qp.c b/drivers/infiniband/sw/rdmavt/qp.c index 9e14addd690c..2a13ac660f2b 100644 --- a/drivers/infiniband/sw/rdmavt/qp.c +++ b/drivers/infiniband/sw/rdmavt/qp.c @@ -901,7 +901,8 @@ struct ib_qp *rvt_create_qp(struct ib_pd *ibpd, return ret; bail_ip: - kref_put(&qp->ip->ref, rvt_release_mmap_info); + if (qp->ip) + kref_put(&qp->ip->ref, rvt_release_mmap_info); bail_qpn: free_qpn(&rdi->qp_dev->qpn_table, qp->ibqp.qp_num); -- 2.20.1