From: Leon Romanovsky <leonro@xxxxxxxxxxxx>
There is a chance that device will be removed during device query
operations and it will cause to kernel panic in the flows which
doesn't hold lists_rwsem semaphore.
Fixes: e5c9469efcb1 ("RDMA/netlink: Add nldev device doit implementation")
Reviewed-by: Mark Bloch <markb@xxxxxxxxxxxx>
Signed-off-by: Leon Romanovsky <leonro@xxxxxxxxxxxx>
---
drivers/infiniband/core/nldev.c | 25 +++++++++++++++----------
1 file changed, 15 insertions(+), 10 deletions(-)
diff --git a/drivers/infiniband/core/nldev.c b/drivers/infiniband/core/nldev.c
index 2b631307349d..e3033d7a4029 100644
--- a/drivers/infiniband/core/nldev.c
+++ b/drivers/infiniband/core/nldev.c
@@ -141,36 +141,41 @@ static int nldev_get_doit(struct sk_buff *skb, struct nlmsghdr *nlh,
struct ib_device *device;
struct sk_buff *msg;
u32 index;
- int err;
+ int ret = -ENOMEM;
- err = nlmsg_parse(nlh, 0, tb, RDMA_NLDEV_ATTR_MAX - 1,
+ ret = nlmsg_parse(nlh, 0, tb, RDMA_NLDEV_ATTR_MAX - 1,
nldev_policy, extack);
- if (err || !tb[RDMA_NLDEV_ATTR_DEV_INDEX])
+ if (ret || !tb[RDMA_NLDEV_ATTR_DEV_INDEX])
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;
msg = nlmsg_new(NLMSG_DEFAULT_SIZE, GFP_KERNEL);
if (!msg)
- return -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;
- }
+ ret = fill_dev_info(msg, device);
+ if (ret)
+ 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 ret;
}
static int _nldev_get_dumpit(struct ib_device *device,
--
2.15.1
--
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