From: Dai Ngo <dai.ngo@oracle.com>
Date: Thu, 29 Oct 2020 19:07:16 +0000 (-0400)
Subject: NFSD: fix missing refcount in nfsd4_copy by nfsd4_do_async_copy
X-Git-Tag: v5.9.9~111
X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=d7cad33df1cab120b83099a8f45d2486dd56a8fa;p=thirdparty%2Fkernel%2Fstable.git

NFSD: fix missing refcount in nfsd4_copy by nfsd4_do_async_copy

[ Upstream commit 49a361327332c9221438397059067f9b205f690d ]

Need to initialize nfsd4_copy's refcount to 1 to avoid use-after-free
warning when nfs4_put_copy is called from nfsd4_cb_offload_release.

Fixes: ce0887ac96d3 ("NFSD add nfs4 inter ssc to nfsd4_copy")
Signed-off-by: Dai Ngo <dai.ngo@oracle.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---

diff --git a/fs/nfsd/nfs4proc.c b/fs/nfsd/nfs4proc.c
index 80effaa18b7b2..3ba17b5fc9286 100644
--- a/fs/nfsd/nfs4proc.c
+++ b/fs/nfsd/nfs4proc.c
@@ -1486,6 +1486,7 @@ do_callback:
 	cb_copy = kzalloc(sizeof(struct nfsd4_copy), GFP_KERNEL);
 	if (!cb_copy)
 		goto out;
+	refcount_set(&cb_copy->refcount, 1);
 	memcpy(&cb_copy->cp_res, &copy->cp_res, sizeof(copy->cp_res));
 	cb_copy->cp_clp = copy->cp_clp;
 	cb_copy->nfserr = copy->nfserr;