> -----Original Message-----
> From: Bernard Metzler <bmt@xxxxxxxxxxxxxx>
> Sent: Thursday, December 12, 2024 3:36 PM
> To: linux-rdma@xxxxxxxxxxxxxxx
> Cc: jgg@xxxxxxxx; leon@xxxxxxxxxx; linux-kernel@xxxxxxxxxxxxxxx;
> netdev@xxxxxxxxxxxxxxx; syzkaller-bugs@xxxxxxxxxxxxxxxx;
> zyjzyj2000@xxxxxxxxx; Bernard Metzler <BMT@xxxxxxxxxxxxxx>;
> syzbot+4b87489410b4efd181bf@xxxxxxxxxxxxxxxxxxxxxxxxx
> Subject: [PATCH RESEND] RDMA/siw: Remove direct link to net_device
>
> Do not manage a per device direct link to net_device. Rely
> on associated ib_devices net_device management, not doubling
> the effort locally. A badly managed local link to net_device
> was causing a 'KASAN: slab-use-after-free' exception during
> siw_query_port() call.
>
> Fixes: bdcf26bf9b3a ("rdma/siw: network and RDMA core interface")
> Reported-by: syzbot+4b87489410b4efd181bf@xxxxxxxxxxxxxxxxxxxxxxxxx
> Link: https://syzkaller.appspot.com/bug?extid=4b87489410b4efd181bf
> Signed-off-by: Bernard Metzler <bmt@xxxxxxxxxxxxxx>
> ---
> drivers/infiniband/sw/siw/siw.h | 7 +++---
> drivers/infiniband/sw/siw/siw_cm.c | 31 +++++++++++++++++++++------
> drivers/infiniband/sw/siw/siw_main.c | 15 +------------
> drivers/infiniband/sw/siw/siw_verbs.c | 27 +++++++++++++++++------
> 4 files changed, 50 insertions(+), 30 deletions(-)
>
> diff --git a/drivers/infiniband/sw/siw/siw.h
> b/drivers/infiniband/sw/siw/siw.h
> index 86d4d6a2170e..ea5eee50dc39 100644
> --- a/drivers/infiniband/sw/siw/siw.h
> +++ b/drivers/infiniband/sw/siw/siw.h
> @@ -46,6 +46,9 @@
> */
> #define SIW_IRQ_MAXBURST_SQ_ACTIVE 4
>
> +/* There is always only a port 1 per siw device */
> +#define SIW_PORT 1
> +
> struct siw_dev_cap {
> int max_qp;
> int max_qp_wr;
> @@ -69,16 +72,12 @@ struct siw_pd {
>
> struct siw_device {
> struct ib_device base_dev;
> - struct net_device *netdev;
> struct siw_dev_cap attrs;
>
> u32 vendor_part_id;
> int numa_node;
> char raw_gid[ETH_ALEN];
>
> - /* physical port state (only one port per device) */
> - enum ib_port_state state;
> -
> spinlock_t lock;
>
> struct xarray qp_xa;
> diff --git a/drivers/infiniband/sw/siw/siw_cm.c
> b/drivers/infiniband/sw/siw/siw_cm.c
> index 86323918a570..b157bd01e70b 100644
> --- a/drivers/infiniband/sw/siw/siw_cm.c
> +++ b/drivers/infiniband/sw/siw/siw_cm.c
> @@ -1759,6 +1759,7 @@ int siw_create_listen(struct iw_cm_id *id, int
> backlog)
> {
> struct socket *s;
> struct siw_cep *cep = NULL;
> + struct net_device *ndev = NULL;
> struct siw_device *sdev = to_siw_dev(id->device);
> int addr_family = id->local_addr.ss_family;
> int rv = 0;
> @@ -1779,9 +1780,15 @@ int siw_create_listen(struct iw_cm_id *id, int
> backlog)
> struct sockaddr_in *laddr = &to_sockaddr_in(id->local_addr);
>
> /* For wildcard addr, limit binding to current device only */
> - if (ipv4_is_zeronet(laddr->sin_addr.s_addr))
> - s->sk->sk_bound_dev_if = sdev->netdev->ifindex;
> -
> + if (ipv4_is_zeronet(laddr->sin_addr.s_addr)) {
> + ndev = ib_device_get_netdev(id->device, SIW_PORT);
> + if (ndev) {
> + s->sk->sk_bound_dev_if = ndev->ifindex;
> + } else {
> + rv = -ENODEV;
> + goto error;
> + }
> + }
> rv = s->ops->bind(s, (struct sockaddr *)laddr,
> sizeof(struct sockaddr_in));
> } else {
> @@ -1797,9 +1804,15 @@ int siw_create_listen(struct iw_cm_id *id, int
> backlog)
> }
>
> /* For wildcard addr, limit binding to current device only */
> - if (ipv6_addr_any(&laddr->sin6_addr))
> - s->sk->sk_bound_dev_if = sdev->netdev->ifindex;
> -
> + if (ipv6_addr_any(&laddr->sin6_addr)) {
> + ndev = ib_device_get_netdev(id->device, SIW_PORT);
> + if (ndev) {
> + s->sk->sk_bound_dev_if = ndev->ifindex;
> + } else {
> + rv = -ENODEV;
> + goto error;
> + }
> + }
> rv = s->ops->bind(s, (struct sockaddr *)laddr,
> sizeof(struct sockaddr_in6));
> }
> @@ -1861,6 +1874,9 @@ int siw_create_listen(struct iw_cm_id *id, int
> backlog)
> list_add_tail(&cep->listenq, (struct list_head *)id->provider_data);
> cep->state = SIW_EPSTATE_LISTENING;
>
> + if (ndev)
> + dev_put(ndev);
> +
> siw_dbg(id->device, "Listen at laddr %pISp\n", &id->local_addr);
>
> return 0;
> @@ -1880,6 +1896,9 @@ int siw_create_listen(struct iw_cm_id *id, int
> backlog)
> }
> sock_release(s);
>
> + if (ndev)
> + dev_put(ndev);
> +
> return rv;
> }
>
> diff --git a/drivers/infiniband/sw/siw/siw_main.c
> b/drivers/infiniband/sw/siw/siw_main.c
> index 17abef48abcd..14d3103aee6f 100644
> --- a/drivers/infiniband/sw/siw/siw_main.c
> +++ b/drivers/infiniband/sw/siw/siw_main.c
> @@ -287,7 +287,6 @@ static struct siw_device *siw_device_create(struct
> net_device *netdev)
> return NULL;
>
> base_dev = &sdev->base_dev;
> - sdev->netdev = netdev;
>
> if (netdev->addr_len) {
> memcpy(sdev->raw_gid, netdev->dev_addr,
> @@ -381,12 +380,10 @@ static int siw_netdev_event(struct notifier_block
> *nb, unsigned long event,
>
> switch (event) {
> case NETDEV_UP:
> - sdev->state = IB_PORT_ACTIVE;
> siw_port_event(sdev, 1, IB_EVENT_PORT_ACTIVE);
> break;
>
> case NETDEV_DOWN:
> - sdev->state = IB_PORT_DOWN;
> siw_port_event(sdev, 1, IB_EVENT_PORT_ERR);
> break;
>
> @@ -407,12 +404,8 @@ static int siw_netdev_event(struct notifier_block *nb,
> unsigned long event,
> siw_port_event(sdev, 1, IB_EVENT_LID_CHANGE);
> break;
> /*
> - * Todo: Below netdev events are currently not handled.
> + * All other events are not handled
> */
> - case NETDEV_CHANGEMTU:
> - case NETDEV_CHANGE:
> - break;
> -
> default:
> break;
> }
> @@ -442,12 +435,6 @@ static int siw_newlink(const char *basedev_name,
> struct net_device *netdev)
> sdev = siw_device_create(netdev);
> if (sdev) {
> dev_dbg(&netdev->dev, "siw: new device\n");
> -
> - if (netif_running(netdev) && netif_carrier_ok(netdev))
> - sdev->state = IB_PORT_ACTIVE;
> - else
> - sdev->state = IB_PORT_DOWN;
> -
> ib_mark_name_assigned_by_user(&sdev->base_dev);
> rv = siw_device_register(sdev, basedev_name);
> if (rv)
> diff --git a/drivers/infiniband/sw/siw/siw_verbs.c
> b/drivers/infiniband/sw/siw/siw_verbs.c
> index 986666c19378..35f3744a3007 100644
> --- a/drivers/infiniband/sw/siw/siw_verbs.c
> +++ b/drivers/infiniband/sw/siw/siw_verbs.c
> @@ -171,21 +171,29 @@ int siw_query_device(struct ib_device *base_dev,
> struct ib_device_attr *attr,
> int siw_query_port(struct ib_device *base_dev, u32 port,
> struct ib_port_attr *attr)
> {
> - struct siw_device *sdev = to_siw_dev(base_dev);
> + struct net_device *ndev;
> int rv;
>
> memset(attr, 0, sizeof(*attr));
>
> rv = ib_get_eth_speed(base_dev, port, &attr->active_speed,
> &attr->active_width);
> + if (rv)
> + return rv;
> +
> + ndev = ib_device_get_netdev(base_dev, SIW_PORT);
> + if (!ndev)
> + return -ENODEV;
> +
> attr->gid_tbl_len = 1;
> attr->max_msg_sz = -1;
> - attr->max_mtu = ib_mtu_int_to_enum(sdev->netdev->mtu);
> - attr->active_mtu = ib_mtu_int_to_enum(sdev->netdev->mtu);
> - attr->phys_state = sdev->state == IB_PORT_ACTIVE ?
> + attr->max_mtu = ib_mtu_int_to_enum(ndev->max_mtu);
> + attr->active_mtu = ib_mtu_int_to_enum(READ_ONCE(ndev->mtu));
> + attr->phys_state = (netif_running(ndev) && netif_carrier_ok(ndev)) ?
> IB_PORT_PHYS_STATE_LINK_UP : IB_PORT_PHYS_STATE_DISABLED;
> + attr->state = attr->phys_state == IB_PORT_PHYS_STATE_LINK_UP ?
> + IB_PORT_ACTIVE : IB_PORT_DOWN;
> attr->port_cap_flags = IB_PORT_CM_SUP | IB_PORT_DEVICE_MGMT_SUP;
> - attr->state = sdev->state;
> /*
> * All zero
> *
> @@ -199,6 +207,7 @@ int siw_query_port(struct ib_device *base_dev, u32
> port,
> * attr->subnet_timeout = 0;
> * attr->init_type_repy = 0;
> */
> + dev_put(ndev);
> return rv;
> }
>
> @@ -506,6 +515,7 @@ int siw_query_qp(struct ib_qp *base_qp, struct
> ib_qp_attr *qp_attr,
> {
> struct siw_qp *qp;
> struct siw_device *sdev;
The sdev is no longer needed. Sorry for not catching it.
I'll resend v2.
> + struct net_device *ndev;
>
> if (base_qp && qp_attr && qp_init_attr) {
> qp = to_siw_qp(base_qp);
> @@ -513,13 +523,17 @@ int siw_query_qp(struct ib_qp *base_qp, struct
> ib_qp_attr *qp_attr,
> } else {
> return -EINVAL;
> }
> + ndev = ib_device_get_netdev(base_qp->device, SIW_PORT);
> + if (!ndev)
> + return -ENODEV;
> +
> qp_attr->qp_state = siw_qp_state_to_ib_qp_state[qp->attrs.state];
> qp_attr->cap.max_inline_data = SIW_MAX_INLINE;
> qp_attr->cap.max_send_wr = qp->attrs.sq_size;
> qp_attr->cap.max_send_sge = qp->attrs.sq_max_sges;
> qp_attr->cap.max_recv_wr = qp->attrs.rq_size;
> qp_attr->cap.max_recv_sge = qp->attrs.rq_max_sges;
> - qp_attr->path_mtu = ib_mtu_int_to_enum(sdev->netdev->mtu);
> + qp_attr->path_mtu = ib_mtu_int_to_enum(READ_ONCE(ndev->mtu));
> qp_attr->max_rd_atomic = qp->attrs.irq_size;
> qp_attr->max_dest_rd_atomic = qp->attrs.orq_size;
>
> @@ -534,6 +548,7 @@ int siw_query_qp(struct ib_qp *base_qp, struct
> ib_qp_attr *qp_attr,
>
> qp_init_attr->cap = qp_attr->cap;
>
> + dev_put(ndev);
> return 0;
> }
>
> --
> 2.38.1
