From: Parav Pandit <parav@xxxxxxxxxxxx>
When AF_IB addresses are used during rdma_resolve_addr(), currently lock
is not held. A cma device can get removed while such list traversal is
in progress which may lead to crash.
Therefore, hold a lock while traversing the list which avoids such
situation.
This patch doesn't come as an outcome of real crash, but from code review.
Cc: <stable@xxxxxxxxxxxxxxx> # 3.10
Fixes: f17df3b0d ("RDMA/cma: Add support for AF_IB to rdma_resolve_addr()")
Signed-off-by: Parav Pandit <parav@xxxxxxxxxxxx>
Reviewed-by: Daniel Jurgens <danielj@xxxxxxxxxxxx>
Signed-off-by: Leon Romanovsky <leonro@xxxxxxxxxxxx>
---
Changelog v0->v1:
* Updated commit message to replace "This patch is not tested"
sentence, to more adequate variant.
---
drivers/infiniband/core/cma.c | 12 +++++++-----
1 file changed, 7 insertions(+), 5 deletions(-)
diff --git a/drivers/infiniband/core/cma.c b/drivers/infiniband/core/cma.c
index 4ba77f4e7098..7d89a21a0483 100644
--- a/drivers/infiniband/core/cma.c
+++ b/drivers/infiniband/core/cma.c
@@ -724,6 +724,7 @@ static int cma_resolve_ib_dev(struct rdma_id_private *id_priv)
dgid = (union ib_gid *) &addr->sib_addr;
pkey = ntohs(addr->sib_pkey);
+ mutex_lock(&lock);
list_for_each_entry(cur_dev, &dev_list, list) {
for (p = 1; p <= cur_dev->device->phys_port_cnt; ++p) {
if (!rdma_cap_af_ib(cur_dev->device, p))
@@ -750,18 +751,19 @@ static int cma_resolve_ib_dev(struct rdma_id_private *id_priv)
cma_dev = cur_dev;
sgid = gid;
id_priv->id.port_num = p;
+ goto found;
}
}
}
}
-
- if (!cma_dev)
- return -ENODEV;
+ mutex_unlock(&lock);
+ return -ENODEV;
found:
cma_attach_to_dev(id_priv, cma_dev);
- addr = (struct sockaddr_ib *) cma_src_addr(id_priv);
- memcpy(&addr->sib_addr, &sgid, sizeof sgid);
+ mutex_unlock(&lock);
+ addr = (struct sockaddr_ib *)cma_src_addr(id_priv);
+ memcpy(&addr->sib_addr, &sgid, sizeof(sgid));
cma_translate_ib(addr, &id_priv->id.route.addr.dev_addr);
return 0;
}
--
2.14.4
