This is a note to let you know that I've just added the patch titled
NFS prevent double free in async nfs4_exchange_id
to the 4.9-stable tree which can be found at:
http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary
The filename of the patch is:
nfs-prevent-double-free-in-async-nfs4_exchange_id.patch
and it can be found in the queue-4.9 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@xxxxxxxxxxxxxxx> know about it.
>From 63513232f8cd219dcaa5eafae028740ed3067d83 Mon Sep 17 00:00:00 2001
From: Olga Kornievskaia <kolga@xxxxxxxxxx>
Date: Mon, 13 Mar 2017 10:36:19 -0400
Subject: NFS prevent double free in async nfs4_exchange_id
From: Olga Kornievskaia <kolga@xxxxxxxxxx>
commit 63513232f8cd219dcaa5eafae028740ed3067d83 upstream.
Since rpc_task is async, the release function should be called which
will free the impl_id, scope, and owner.
Trond pointed at 2 more problems:
-- use of client pointer after free in the nfs4_exchangeid_release() function
-- cl_count mismatch if rpc_run_task() isn't run
Fixes: 8d89bd70bc9 ("NFS setup async exchange_id")
Signed-off-by: Olga Kornievskaia <kolga@xxxxxxxxxx>
Signed-off-by: Anna Schumaker <Anna.Schumaker@xxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
fs/nfs/nfs4proc.c | 9 ++++-----
1 file changed, 4 insertions(+), 5 deletions(-)
--- a/fs/nfs/nfs4proc.c
+++ b/fs/nfs/nfs4proc.c
@@ -7426,11 +7426,11 @@ static void nfs4_exchange_id_release(voi
struct nfs41_exchange_id_data *cdata =
(struct nfs41_exchange_id_data *)data;
- nfs_put_client(cdata->args.client);
if (cdata->xprt) {
xprt_put(cdata->xprt);
rpc_clnt_xprt_switch_put(cdata->args.client->cl_rpcclient);
}
+ nfs_put_client(cdata->args.client);
kfree(cdata->res.impl_id);
kfree(cdata->res.server_scope);
kfree(cdata->res.server_owner);
@@ -7537,10 +7537,8 @@ static int _nfs4_proc_exchange_id(struct
task_setup_data.callback_data = calldata;
task = rpc_run_task(&task_setup_data);
- if (IS_ERR(task)) {
- status = PTR_ERR(task);
- goto out_impl_id;
- }
+ if (IS_ERR(task))
+ return PTR_ERR(task);
if (!xprt) {
status = rpc_wait_for_completion_task(task);
@@ -7568,6 +7566,7 @@ out_server_owner:
kfree(calldata->res.server_owner);
out_calldata:
kfree(calldata);
+ nfs_put_client(clp);
goto out;
}
Patches currently in stable-queue which might be from kolga@xxxxxxxxxx are
queue-4.9/nfs-prevent-double-free-in-async-nfs4_exchange_id.patch