diff mbox series

[4.19,033/206] nfsd: Fix svc_xprt refcnt leak when setup callback client failed

Message ID 20200623195318.610731014@linuxfoundation.org
State New
Headers show
Series None | expand

Commit Message

Greg Kroah-Hartman June 23, 2020, 7:56 p.m. UTC 
From: Xiyu Yang <xiyuyang19@fudan.edu.cn>

[ Upstream commit a4abc6b12eb1f7a533c2e7484cfa555454ff0977 ]

nfsd4_process_cb_update() invokes svc_xprt_get(), which increases the
refcount of the "c->cn_xprt".

The reference counting issue happens in one exception handling path of
nfsd4_process_cb_update(). When setup callback client failed, the
function forgets to decrease the refcnt increased by svc_xprt_get(),
causing a refcnt leak.

Fix this issue by calling svc_xprt_put() when setup callback client
failed.

Signed-off-by: Xiyu Yang <xiyuyang19@fudan.edu.cn>
Signed-off-by: Xin Tan <tanxin.ctf@gmail.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
 fs/nfsd/nfs4callback.c | 2 ++
 1 file changed, 2 insertions(+)
diff mbox series

Patch

diff --git a/fs/nfsd/nfs4callback.c b/fs/nfsd/nfs4callback.c
index ebbb0285addb0..7ee417b685e98 100644
--- a/fs/nfsd/nfs4callback.c
+++ b/fs/nfsd/nfs4callback.c
@@ -1149,6 +1149,8 @@  static void nfsd4_process_cb_update(struct nfsd4_callback *cb)
 	err = setup_callback_client(clp, &conn, ses);
 	if (err) {
 		nfsd4_mark_cb_down(clp, err);
+		if (c)
+			svc_xprt_put(c->cn_xprt);
 		return;
 	}
 }