Re: [PATCH RESEND v2] RDMA/siw: Remove direct link to net_device

Zhu Yanjun
2024-12-15T17:37:52Z

在 2024/12/14 13:37, Zhu Yanjun 写道:
> 在 2024/12/12 16:18, Bernard Metzler 写道:
>> 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@syzkaller.appspotmail.com
>> Link: https://syzkaller.appspot.com/bug?extid=4b87489410b4efd181bf
>> Signed-off-by: Bernard Metzler <bmt@zurich.ibm.com>
>> ---
>>   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 | 35 ++++++++++++++++++---------
>>   4 files changed, 53 insertions(+), 35 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);
>> +
>
> dev_put will invoke netdev_put. In netdev_put, dev is checked.
> Thus, no need to check ndev before dev_put function?

Reviewed-by: Zhu Yanjun <yanjun.zhu@linux.dev>

Zhu Yanjun

>
> static inline void netdev_put(struct net_device *dev,
>                   netdevice_tracker *tracker)
> {
>     if (dev) {
>         netdev_tracker_free(dev, tracker);
>         __dev_put(dev);
>     }
> }
>
>>       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..7ca0297d68a4 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;
>>   }
>> @@ -505,21 +514,24 @@ int siw_query_qp(struct ib_qp *base_qp, struct
>> ib_qp_attr *qp_attr,
>>            int qp_attr_mask, struct ib_qp_init_attr *qp_init_attr)
>>   {
>>       struct siw_qp *qp;
>> -    struct siw_device *sdev;
>> +    struct net_device *ndev;
>> -    if (base_qp && qp_attr && qp_init_attr) {
>> +    if (base_qp && qp_attr && qp_init_attr)
>>           qp = to_siw_qp(base_qp);
>> -        sdev = to_siw_dev(base_qp->device);
>> -    } else {
>> +    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 +546,7 @@ 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;
>>   }
>

--
Best Regards,
Yanjun.Zhu