From: Erez Shitrit <erezsh@xxxxxxxxxxxx>
If from some reason the SM responses to path query request with response
that doesn't contain the exact SGID, ipoib should warn and change that
part of the response before push it to the path record DB.
Otherwise, new record will be added to the path record DB with no access
to them from the ipoib.
Demonstration of the bug is as the follow:
ipoib wants to send to GID fe80:0000:0000:0000:0002:c903:00ef:5ee2, it
creates new record in the DB with that gid as a key, and issues a new
request to the sm.
Now, the SM from some reason returns path-record with other SGID (for
example, fe80:0000:0000:0001:0002:c903:00ef:5ee2 that contains the local
subnet prefix) now ipoib will overwrite the current entry with the new
one, and if new request to the original GID arrives ipoib will not find
it in the DB (was overwritten) and will create new record that in its
turn will also be overwritten by the response from the SM, and so on
till the driver eats all the device memory.
Signed-off-by: Erez Shitrit <erezsh@xxxxxxxxxxxx>
Signed-off-by: Leon Romanovsky <leon@xxxxxxxxxx>
---
drivers/infiniband/ulp/ipoib/ipoib_main.c | 10 ++++++++++
1 file changed, 10 insertions(+)
diff --git a/drivers/infiniband/ulp/ipoib/ipoib_main.c b/drivers/infiniband/ulp/ipoib/ipoib_main.c
index 12b7f911f0e5..b173d618c59c 100644
--- a/drivers/infiniband/ulp/ipoib/ipoib_main.c
+++ b/drivers/infiniband/ulp/ipoib/ipoib_main.c
@@ -775,6 +775,16 @@ static void path_rec_completion(int status,
spin_lock_irqsave(&priv->lock, flags);
if (!IS_ERR_OR_NULL(ah)) {
+ /* check there is no mismatch from the request */
+ if (memcmp(pathrec->dgid.raw, path->pathrec.dgid.raw,
+ sizeof(union ib_gid))) {
+ pr_warn("%s got PathRec for gid %pI6 while asked for %pI6\n",
+ dev->name, pathrec->dgid.raw, path->pathrec.dgid.raw);
+ /* overwrite the response from the sm before copy to the db */
+ memcpy(pathrec->dgid.raw, path->pathrec.dgid.raw,
+ sizeof(union ib_gid));
+ }
+
path->pathrec = *pathrec;
old_ah = path->ah;
--
2.15.0
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