From: Leon Romanovsky leonro@mellanox.com
[ Upstream commit f8978bd95cf92f869f3d9b34c1b699f49253b8c6 ]
Holding locks is mandatory when calling __ib_device_get_by_index, otherwise there are races during the list iteration with device removal.
Since the locks are static to device.c, __ib_device_get_by_index can never be called correctly by any user out side the file.
Make the function static and provide a safe function that gets the correct locks and returns a kref'd pointer. Fix all callers.
Fixes: e5c9469efcb1 ("RDMA/netlink: Add nldev device doit implementation") Fixes: c3f66f7b0052 ("RDMA/netlink: Implement nldev port doit callback") Fixes: 7d02f605f0dc ("RDMA/netlink: Add nldev port dumpit implementation") Reviewed-by: Mark Bloch markb@mellanox.com Signed-off-by: Leon Romanovsky leonro@mellanox.com Signed-off-by: Jason Gunthorpe jgg@mellanox.com Signed-off-by: Sasha Levin alexander.levin@microsoft.com --- drivers/infiniband/core/core_priv.h | 2 +- drivers/infiniband/core/device.c | 18 ++++++++++++- drivers/infiniband/core/nldev.c | 54 ++++++++++++++++++++++++------------- 3 files changed, 54 insertions(+), 20 deletions(-)
diff --git a/drivers/infiniband/core/core_priv.h b/drivers/infiniband/core/core_priv.h index a1d687a664f8..66f0268f37a6 100644 --- a/drivers/infiniband/core/core_priv.h +++ b/drivers/infiniband/core/core_priv.h @@ -314,7 +314,7 @@ static inline int ib_mad_enforce_security(struct ib_mad_agent_private *map, } #endif
-struct ib_device *__ib_device_get_by_index(u32 ifindex); +struct ib_device *ib_device_get_by_index(u32 ifindex); /* RDMA device netlink */ void nldev_init(void); void nldev_exit(void); diff --git a/drivers/infiniband/core/device.c b/drivers/infiniband/core/device.c index 84fc32a2c8b3..f65f64cb8455 100644 --- a/drivers/infiniband/core/device.c +++ b/drivers/infiniband/core/device.c @@ -134,7 +134,7 @@ static int ib_device_check_mandatory(struct ib_device *device) return 0; }
-struct ib_device *__ib_device_get_by_index(u32 index) +static struct ib_device *__ib_device_get_by_index(u32 index) { struct ib_device *device;
@@ -145,6 +145,22 @@ struct ib_device *__ib_device_get_by_index(u32 index) return NULL; }
+/* + * Caller is responsible to return refrerence count by calling put_device() + */ +struct ib_device *ib_device_get_by_index(u32 index) +{ + struct ib_device *device; + + down_read(&lists_rwsem); + device = __ib_device_get_by_index(index); + if (device) + get_device(&device->dev); + + up_read(&lists_rwsem); + return device; +} + static struct ib_device *__ib_device_get_by_name(const char *name) { struct ib_device *device; diff --git a/drivers/infiniband/core/nldev.c b/drivers/infiniband/core/nldev.c index 2fae850a3eff..4fbb9681f5cf 100644 --- a/drivers/infiniband/core/nldev.c +++ b/drivers/infiniband/core/nldev.c @@ -142,27 +142,34 @@ static int nldev_get_doit(struct sk_buff *skb, struct nlmsghdr *nlh,
index = nla_get_u32(tb[RDMA_NLDEV_ATTR_DEV_INDEX]);
- device = __ib_device_get_by_index(index); + device = ib_device_get_by_index(index); if (!device) return -EINVAL;
msg = nlmsg_new(NLMSG_DEFAULT_SIZE, GFP_KERNEL); - if (!msg) - return -ENOMEM; + if (!msg) { + err = -ENOMEM; + goto err; + }
nlh = nlmsg_put(msg, NETLINK_CB(skb).portid, nlh->nlmsg_seq, RDMA_NL_GET_TYPE(RDMA_NL_NLDEV, RDMA_NLDEV_CMD_GET), 0, 0);
err = fill_dev_info(msg, device); - if (err) { - nlmsg_free(msg); - return err; - } + if (err) + goto err_free;
nlmsg_end(msg, nlh);
+ put_device(&device->dev); return rdma_nl_unicast(msg, NETLINK_CB(skb).portid); + +err_free: + nlmsg_free(msg); +err: + put_device(&device->dev); + return err; }
static int _nldev_get_dumpit(struct ib_device *device, @@ -220,31 +227,40 @@ static int nldev_port_get_doit(struct sk_buff *skb, struct nlmsghdr *nlh, return -EINVAL;
index = nla_get_u32(tb[RDMA_NLDEV_ATTR_DEV_INDEX]); - device = __ib_device_get_by_index(index); + device = ib_device_get_by_index(index); if (!device) return -EINVAL;
port = nla_get_u32(tb[RDMA_NLDEV_ATTR_PORT_INDEX]); - if (!rdma_is_port_valid(device, port)) - return -EINVAL; + if (!rdma_is_port_valid(device, port)) { + err = -EINVAL; + goto err; + }
msg = nlmsg_new(NLMSG_DEFAULT_SIZE, GFP_KERNEL); - if (!msg) - return -ENOMEM; + if (!msg) { + err = -ENOMEM; + goto err; + }
nlh = nlmsg_put(msg, NETLINK_CB(skb).portid, nlh->nlmsg_seq, RDMA_NL_GET_TYPE(RDMA_NL_NLDEV, RDMA_NLDEV_CMD_GET), 0, 0);
err = fill_port_info(msg, device, port); - if (err) { - nlmsg_free(msg); - return err; - } + if (err) + goto err_free;
nlmsg_end(msg, nlh); + put_device(&device->dev);
return rdma_nl_unicast(msg, NETLINK_CB(skb).portid); + +err_free: + nlmsg_free(msg); +err: + put_device(&device->dev); + return err; }
static int nldev_port_get_dumpit(struct sk_buff *skb, @@ -265,7 +281,7 @@ static int nldev_port_get_dumpit(struct sk_buff *skb, return -EINVAL;
ifindex = nla_get_u32(tb[RDMA_NLDEV_ATTR_DEV_INDEX]); - device = __ib_device_get_by_index(ifindex); + device = ib_device_get_by_index(ifindex); if (!device) return -EINVAL;
@@ -299,7 +315,9 @@ static int nldev_port_get_dumpit(struct sk_buff *skb, nlmsg_end(skb, nlh); }
-out: cb->args[0] = idx; +out: + put_device(&device->dev); + cb->args[0] = idx; return skb->len; }