2019-01-04 08:19:11

by Myungho Jung

[permalink] [raw]
Subject: [PATCH] RDMA/cma: Rollback source IP address if failing to acquire device

If cma_acquire_dev_by_src_ip() returns error in addr_handler(), the
device state changes back to RDMA_CM_ADDR_BOUND but the resolved source
IP address is still left. After that, if rdma_destroy_id() is called
after rdma_listen(), the device is freed without removed from
listen_any_list in cma_cancel_operation(). Revert to the previous IP
address if acquiring device fails.

Reported-by: [email protected]
Signed-off-by: Myungho Jung <[email protected]>
---
drivers/infiniband/core/cma.c | 8 +++++++-
1 file changed, 7 insertions(+), 1 deletion(-)

diff --git a/drivers/infiniband/core/cma.c b/drivers/infiniband/core/cma.c
index 63a7cc00bae0..d27c3b154e71 100644
--- a/drivers/infiniband/core/cma.c
+++ b/drivers/infiniband/core/cma.c
@@ -2963,13 +2963,17 @@ static void addr_handler(int status, struct sockaddr *src_addr,
{
struct rdma_id_private *id_priv = context;
struct rdma_cm_event event = {};
+ struct sockaddr *addr;
+ struct sockaddr_storage old_addr;

mutex_lock(&id_priv->handler_mutex);
if (!cma_comp_exch(id_priv, RDMA_CM_ADDR_QUERY,
RDMA_CM_ADDR_RESOLVED))
goto out;

- memcpy(cma_src_addr(id_priv), src_addr, rdma_addr_size(src_addr));
+ addr = cma_src_addr(id_priv);
+ memcpy(&old_addr, addr, rdma_addr_size(addr));
+ memcpy(addr, src_addr, rdma_addr_size(src_addr));
if (!status && !id_priv->cma_dev) {
status = cma_acquire_dev_by_src_ip(id_priv);
if (status)
@@ -2980,6 +2984,8 @@ static void addr_handler(int status, struct sockaddr *src_addr,
}

if (status) {
+ memcpy(addr, &old_addr,
+ rdma_addr_size((struct sockaddr *)&old_addr));
if (!cma_comp_exch(id_priv, RDMA_CM_ADDR_RESOLVED,
RDMA_CM_ADDR_BOUND))
goto out;
--
2.17.1



2019-01-09 14:21:02

by Parav Pandit

[permalink] [raw]
Subject: RE: [PATCH] RDMA/cma: Rollback source IP address if failing to acquire device



> -----Original Message-----
> From: [email protected] <linux-rdma-
> [email protected]> On Behalf Of Myungho Jung
> Sent: Friday, January 4, 2019 12:46 AM
> To: Doug Ledford <[email protected]>; Jason Gunthorpe <[email protected]>
> Cc: [email protected]; [email protected]
> Subject: [PATCH] RDMA/cma: Rollback source IP address if failing to acquire
> device
>
> If cma_acquire_dev_by_src_ip() returns error in addr_handler(), the device
> state changes back to RDMA_CM_ADDR_BOUND but the resolved source IP
> address is still left. After that, if rdma_destroy_id() is called after
> rdma_listen(), the device is freed without removed from listen_any_list in
> cma_cancel_operation(). Revert to the previous IP address if acquiring device
> fails.
>
> Reported-by: [email protected]
> Signed-off-by: Myungho Jung <[email protected]>
> ---
> drivers/infiniband/core/cma.c | 8 +++++++-
> 1 file changed, 7 insertions(+), 1 deletion(-)
>
> diff --git a/drivers/infiniband/core/cma.c b/drivers/infiniband/core/cma.c
> index 63a7cc00bae0..d27c3b154e71 100644
> --- a/drivers/infiniband/core/cma.c
> +++ b/drivers/infiniband/core/cma.c
> @@ -2963,13 +2963,17 @@ static void addr_handler(int status, struct
> sockaddr *src_addr, {
> struct rdma_id_private *id_priv = context;
> struct rdma_cm_event event = {};
> + struct sockaddr *addr;
> + struct sockaddr_storage old_addr;
>
> mutex_lock(&id_priv->handler_mutex);
> if (!cma_comp_exch(id_priv, RDMA_CM_ADDR_QUERY,
> RDMA_CM_ADDR_RESOLVED))
> goto out;
>
> - memcpy(cma_src_addr(id_priv), src_addr,
> rdma_addr_size(src_addr));
> + addr = cma_src_addr(id_priv);
> + memcpy(&old_addr, addr, rdma_addr_size(addr));
Please add a comment here in the patch, why we need to store the old src address and restore back.
/*
* Store the previous src address, so that if we fail to acquire matching rdma device,
* old address can be restored back, which helps to cancel the cma listen operation
* correctly.
*/
> + memcpy(addr, src_addr, rdma_addr_size(src_addr));
> if (!status && !id_priv->cma_dev) {
> status = cma_acquire_dev_by_src_ip(id_priv);
> if (status)
> @@ -2980,6 +2984,8 @@ static void addr_handler(int status, struct sockaddr
> *src_addr,
> }
>
> if (status) {
> + memcpy(addr, &old_addr,
> + rdma_addr_size((struct sockaddr *)&old_addr));
> if (!cma_comp_exch(id_priv, RDMA_CM_ADDR_RESOLVED,
> RDMA_CM_ADDR_BOUND))
> goto out;
> --
> 2.17.1

Reviewed-by: Parav Pandit <[email protected]>

2019-01-10 06:06:01

by Myungho Jung

[permalink] [raw]
Subject: Re: [PATCH] RDMA/cma: Rollback source IP address if failing to acquire device

On Wed, Jan 09, 2019 at 01:28:34PM +0000, Parav Pandit wrote:
>
>
> > -----Original Message-----
> > From: [email protected] <linux-rdma-
> > [email protected]> On Behalf Of Myungho Jung
> > Sent: Friday, January 4, 2019 12:46 AM
> > To: Doug Ledford <[email protected]>; Jason Gunthorpe <[email protected]>
> > Cc: [email protected]; [email protected]
> > Subject: [PATCH] RDMA/cma: Rollback source IP address if failing to acquire
> > device
> >
> > If cma_acquire_dev_by_src_ip() returns error in addr_handler(), the device
> > state changes back to RDMA_CM_ADDR_BOUND but the resolved source IP
> > address is still left. After that, if rdma_destroy_id() is called after
> > rdma_listen(), the device is freed without removed from listen_any_list in
> > cma_cancel_operation(). Revert to the previous IP address if acquiring device
> > fails.
> >
> > Reported-by: [email protected]
> > Signed-off-by: Myungho Jung <[email protected]>
> > ---
> > drivers/infiniband/core/cma.c | 8 +++++++-
> > 1 file changed, 7 insertions(+), 1 deletion(-)
> >
> > diff --git a/drivers/infiniband/core/cma.c b/drivers/infiniband/core/cma.c
> > index 63a7cc00bae0..d27c3b154e71 100644
> > --- a/drivers/infiniband/core/cma.c
> > +++ b/drivers/infiniband/core/cma.c
> > @@ -2963,13 +2963,17 @@ static void addr_handler(int status, struct
> > sockaddr *src_addr, {
> > struct rdma_id_private *id_priv = context;
> > struct rdma_cm_event event = {};
> > + struct sockaddr *addr;
> > + struct sockaddr_storage old_addr;
> >
> > mutex_lock(&id_priv->handler_mutex);
> > if (!cma_comp_exch(id_priv, RDMA_CM_ADDR_QUERY,
> > RDMA_CM_ADDR_RESOLVED))
> > goto out;
> >
> > - memcpy(cma_src_addr(id_priv), src_addr,
> > rdma_addr_size(src_addr));
> > + addr = cma_src_addr(id_priv);
> > + memcpy(&old_addr, addr, rdma_addr_size(addr));
> Please add a comment here in the patch, why we need to store the old src address and restore back.
> /*
> * Store the previous src address, so that if we fail to acquire matching rdma device,
> * old address can be restored back, which helps to cancel the cma listen operation
> * correctly.
> */
> > + memcpy(addr, src_addr, rdma_addr_size(src_addr));
> > if (!status && !id_priv->cma_dev) {
> > status = cma_acquire_dev_by_src_ip(id_priv);
> > if (status)
> > @@ -2980,6 +2984,8 @@ static void addr_handler(int status, struct sockaddr
> > *src_addr,
> > }
> >
> > if (status) {
> > + memcpy(addr, &old_addr,
> > + rdma_addr_size((struct sockaddr *)&old_addr));
> > if (!cma_comp_exch(id_priv, RDMA_CM_ADDR_RESOLVED,
> > RDMA_CM_ADDR_BOUND))
> > goto out;
> > --
> > 2.17.1
>
> Reviewed-by: Parav Pandit <[email protected]>

Hi Parav,

Thanks for review. Let me update and resubmit patch.

Thanks,
Myungho