[PATCH 3/3] NFSD fixing possible null pointer derefering in copy offload

Olga Kornievskaia
2019-12-04T20:14:03Z

Static checker revealed possible error path leading to possible
NULL pointer dereferencing.

Reported-by: Dan Carpenter <dan.carpenter@oracle.com>
Fixes: e0639dc5805a: ("NFSD introduce async copy feature")
Signed-off-by: Olga Kornievskaia <kolga@netapp.com>
---
fs/nfsd/nfs4proc.c | 6 ++++--
1 file changed, 4 insertions(+), 2 deletions(-)

diff --git a/fs/nfsd/nfs4proc.c b/fs/nfsd/nfs4proc.c
index 187cef6..d33c39c 100644
--- a/fs/nfsd/nfs4proc.c
+++ b/fs/nfsd/nfs4proc.c
@@ -1446,7 +1446,8 @@ static void cleanup_async_copy(struct nfsd4_copy *copy)
{
nfs4_free_copy_state(copy);
nfsd_file_put(copy->nf_dst);
- nfsd_file_put(copy->nf_src);
+ if (copy->cp_intra)
+ nfsd_file_put(copy->nf_src);
spin_lock(&copy->cp_clp->async_lock);
list_del(&copy->copies);
spin_unlock(&copy->cp_clp->async_lock);
@@ -1551,7 +1552,8 @@ static int nfsd4_do_async_copy(void *data)
out:
return status;
out_err:
- cleanup_async_copy(async_copy);
+ if (async_copy)
+ cleanup_async_copy(async_copy);
status = nfserrno(-ENOMEM);
if (!copy->cp_intra)
nfsd4_interssc_disconnect(copy->ss_mnt);
--
1.8.3.1