[PATCH 4.9 62/91] iw_cxgb4: fix srqidx leak during connection abort

From: Greg Kroah-Hartman
Date: Thu Apr 04 2019 - 04:52:08 EST


4.9-stable review patch. If anyone has any objections, please let me know.

------------------

[ Upstream commit f368ff188ae4b3ef6f740a15999ea0373261b619 ]

When an application aborts the connection by moving QP from RTS to ERROR,
then iw_cxgb4's modify_rc_qp() RTS->ERROR logic sets the
*srqidxp to 0 via t4_set_wq_in_error(&qhp->wq, 0), and aborts the
connection by calling c4iw_ep_disconnect().

c4iw_ep_disconnect() does the following:
1. sends up a close_complete_upcall(ep, -ECONNRESET) to libcxgb4.
2. sends abort request CPL to hw.

But, since the close_complete_upcall() is sent before sending the
ABORT_REQ to hw, libcxgb4 would fail to release the srqidx if the
connection holds one. Because, the srqidx is passed up to libcxgb4 only
after corresponding ABORT_RPL is processed by kernel in abort_rpl().

This patch handle the corner-case by moving the call to
close_complete_upcall() from c4iw_ep_disconnect() to abort_rpl(). So that
libcxgb4 is notified about the -ECONNRESET only after abort_rpl(), and
libcxgb4 can relinquish the srqidx properly.

Signed-off-by: Raju Rangoju <rajur@xxxxxxxxxxx>
Signed-off-by: Jason Gunthorpe <jgg@xxxxxxxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
---
drivers/infiniband/hw/cxgb4/cm.c | 5 +++--
1 file changed, 3 insertions(+), 2 deletions(-)

diff --git a/drivers/infiniband/hw/cxgb4/cm.c b/drivers/infiniband/hw/cxgb4/cm.c
index dd18b74cd01d..a2322b2dbd82 100644
--- a/drivers/infiniband/hw/cxgb4/cm.c
+++ b/drivers/infiniband/hw/cxgb4/cm.c
@@ -1872,8 +1872,10 @@ static int abort_rpl(struct c4iw_dev *dev, struct sk_buff *skb)
}
mutex_unlock(&ep->com.mutex);

- if (release)
+ if (release) {
+ close_complete_upcall(ep, -ECONNRESET);
release_ep_resources(ep);
+ }
c4iw_put_ep(&ep->com);
return 0;
}
@@ -3567,7 +3569,6 @@ int c4iw_ep_disconnect(struct c4iw_ep *ep, int abrupt, gfp_t gfp)
if (close) {
if (abrupt) {
set_bit(EP_DISC_ABORT, &ep->com.history);
- close_complete_upcall(ep, -ECONNRESET);
ret = send_abort(ep);
} else {
set_bit(EP_DISC_CLOSE, &ep->com.history);
--
2.19.1