[PATCH AUTOSEL 5.15 25/25] nfsd: zero out pointers after putting nfsd_files on COPY setup error

[Sasha Levin]

From: Jeff Layton <jlayton@xxxxxxxxxx>

[ Upstream commit 1f0001d43d0c0ac2a19a34a914f6595ad97cbc1d ]

At first, I thought this might be a source of nfsd_file overputs, but
the current callers seem to avoid an extra put when nfsd4_verify_copy
returns an error.

Still, it's "bad form" to leave the pointers filled out when we don't
have a reference to them anymore, and that might lead to bugs later.
Zero them out as a defensive coding measure.

Signed-off-by: Jeff Layton <jlayton@xxxxxxxxxx>
Signed-off-by: Chuck Lever <chuck.lever@xxxxxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
---
 fs/nfsd/nfs4proc.c | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/fs/nfsd/nfs4proc.c b/fs/nfsd/nfs4proc.c
index 0a900b9e39eac..57af9c30eb48d 100644
--- a/fs/nfsd/nfs4proc.c
+++ b/fs/nfsd/nfs4proc.c
@@ -1088,8 +1088,10 @@ nfsd4_verify_copy(struct svc_rqst *rqstp, struct nfsd4_compound_state *cstate,
 	return status;
 out_put_dst:
 	nfsd_file_put(*dst);
+	*dst = NULL;
 out_put_src:
 	nfsd_file_put(*src);
+	*src = NULL;
 	goto out;
 }
 
-- 
2.39.0