diff mbox series

[15/31] rdma/siw: create a temporary copy of private data

Message ID a382dd6f7560b1a311484c656216fcdb9de56ff6.1620343860.git.metze@samba.org (mailing list archive)
State Changes Requested
Headers show
Series rdma/siw: fix a lot of deadlocks and use after free bugs | expand

Commit Message

Stefan Metzmacher May 6, 2021, 11:36 p.m. UTC
The final patch will implement a non-blocking connect,
which means that siw_connect() will be split into
siw_connect() and siw_connected().

kernel_bindconnect() will be the last action
in siw_connect(), while the MPA negotiation
is deferred to siw_connected().

We should not rely on the callers private data
pointers to be still valid when siw_connected()
is called, so we better create a copy.

Fixes: 6c52fdc244b5 ("rdma/siw: connection management")
Signed-off-by: Stefan Metzmacher <metze@samba.org>
Cc: Bernard Metzler <bmt@zurich.ibm.com>
Cc: linux-rdma@vger.kernel.org
---
 drivers/infiniband/sw/siw/siw_cm.c | 16 ++++++++++++++--
 1 file changed, 14 insertions(+), 2 deletions(-)

Comments

Bernard Metzler May 11, 2021, 12:15 p.m. UTC | #1
-----"Stefan Metzmacher" <metze@samba.org> wrote: -----

>To: "Bernard Metzler" <bmt@zurich.ibm.com>
>From: "Stefan Metzmacher" <metze@samba.org>
>Date: 05/07/2021 01:38AM
>Cc: linux-rdma@vger.kernel.org, "Stefan Metzmacher" <metze@samba.org>
>Subject: [EXTERNAL] [PATCH 15/31] rdma/siw: create a temporary copy
>of private data
>
>The final patch will implement a non-blocking connect,
>which means that siw_connect() will be split into
>siw_connect() and siw_connected().
>
>kernel_bindconnect() will be the last action
>in siw_connect(), while the MPA negotiation
>is deferred to siw_connected().
>

While it adds complexity, I really like the non-blocking
connect(). It would be much easier to review if a single
patch would introduce that on top of the previous work.

>We should not rely on the callers private data
>pointers to be still valid when siw_connected()
>is called, so we better create a copy.
>
>Fixes: 6c52fdc244b5 ("rdma/siw: connection management")
>Signed-off-by: Stefan Metzmacher <metze@samba.org>
>Cc: Bernard Metzler <bmt@zurich.ibm.com>
>Cc: linux-rdma@vger.kernel.org
>---
> drivers/infiniband/sw/siw/siw_cm.c | 16 ++++++++++++++--
> 1 file changed, 14 insertions(+), 2 deletions(-)
>
>diff --git a/drivers/infiniband/sw/siw/siw_cm.c
>b/drivers/infiniband/sw/siw/siw_cm.c
>index 027bc18cb801..41d3436985a6 100644
>--- a/drivers/infiniband/sw/siw/siw_cm.c
>+++ b/drivers/infiniband/sw/siw/siw_cm.c
>@@ -1519,13 +1519,25 @@ int siw_connect(struct iw_cm_id *id, struct
>iw_cm_conn_param *params)
> 	}
> 	memcpy(cep->mpa.hdr.key, MPA_KEY_REQ, 16);
> 
>+	cep->mpa.pdata = kmemdup(params->private_data, pd_len, GFP_KERNEL);
>+	if (IS_ERR_OR_NULL(cep->mpa.pdata)) {
>+		rv = -ENOMEM;
>+		goto error;
>+	}
>+	cep->mpa.hdr.params.pd_len = pd_len;
>+
> 	cep->state = SIW_EPSTATE_AWAIT_MPAREP;
> 
>-	rv = siw_send_mpareqrep(cep, params->private_data, pd_len);
>+	rv = siw_send_mpareqrep(cep, cep->mpa.pdata,
>+				cep->mpa.hdr.params.pd_len);
> 	/*
> 	 * Reset private data.
> 	 */
>-	cep->mpa.hdr.params.pd_len = 0;
>+	if (cep->mpa.hdr.params.pd_len) {
>+		cep->mpa.hdr.params.pd_len = 0;
>+		kfree(cep->mpa.pdata);
>+		cep->mpa.pdata = NULL;
>+	}
> 
> 	if (rv >= 0) {
> 		rv = siw_cm_queue_work(cep, SIW_CM_WORK_MPATIMEOUT);
>-- 
>2.25.1
>
>
diff mbox series

Patch

diff --git a/drivers/infiniband/sw/siw/siw_cm.c b/drivers/infiniband/sw/siw/siw_cm.c
index 027bc18cb801..41d3436985a6 100644
--- a/drivers/infiniband/sw/siw/siw_cm.c
+++ b/drivers/infiniband/sw/siw/siw_cm.c
@@ -1519,13 +1519,25 @@  int siw_connect(struct iw_cm_id *id, struct iw_cm_conn_param *params)
 	}
 	memcpy(cep->mpa.hdr.key, MPA_KEY_REQ, 16);
 
+	cep->mpa.pdata = kmemdup(params->private_data, pd_len, GFP_KERNEL);
+	if (IS_ERR_OR_NULL(cep->mpa.pdata)) {
+		rv = -ENOMEM;
+		goto error;
+	}
+	cep->mpa.hdr.params.pd_len = pd_len;
+
 	cep->state = SIW_EPSTATE_AWAIT_MPAREP;
 
-	rv = siw_send_mpareqrep(cep, params->private_data, pd_len);
+	rv = siw_send_mpareqrep(cep, cep->mpa.pdata,
+				cep->mpa.hdr.params.pd_len);
 	/*
 	 * Reset private data.
 	 */
-	cep->mpa.hdr.params.pd_len = 0;
+	if (cep->mpa.hdr.params.pd_len) {
+		cep->mpa.hdr.params.pd_len = 0;
+		kfree(cep->mpa.pdata);
+		cep->mpa.pdata = NULL;
+	}
 
 	if (rv >= 0) {
 		rv = siw_cm_queue_work(cep, SIW_CM_WORK_MPATIMEOUT);