From: Jia-Ju Bai <baijiaju1990@gmail.com>
To: bfields@fieldses.org, chuck.lever@oracle.com
Cc: linux-nfs@vger.kernel.org, linux-kernel@vger.kernel.org,
Jia-Ju Bai <baijiaju1990@gmail.com>
Subject: [PATCH] fs: nfsd: Fix three possible null-pointer dereferences
Date: Wed, 24 Jul 2019 16:28:03 +0800 [thread overview]
Message-ID: <20190724082803.1077-1-baijiaju1990@gmail.com> (raw)
In nfs4_xdr_dec_cb_recall(), nfs4_xdr_dec_cb_layout() and
nfs4_xdr_dec_cb_notify_lock(), there is an if statement to check whether
cb is NULL.
When cb is NULL, the three functions all call:
decode_cb_op_status(..., &cb->cb_status);
Thus, possible null-pointer dereferences may occur.
To fix these possible bugs, -EINVAL is returned when cb is NULL.
These bugs are found by a static analysis tool STCheck written by us.
Signed-off-by: Jia-Ju Bai <baijiaju1990@gmail.com>
---
fs/nfsd/nfs4callback.c | 11 ++++++++---
1 file changed, 8 insertions(+), 3 deletions(-)
diff --git a/fs/nfsd/nfs4callback.c b/fs/nfsd/nfs4callback.c
index 397eb7820929..55949a158b6b 100644
--- a/fs/nfsd/nfs4callback.c
+++ b/fs/nfsd/nfs4callback.c
@@ -516,7 +516,8 @@ static int nfs4_xdr_dec_cb_recall(struct rpc_rqst *rqstp,
status = decode_cb_sequence4res(xdr, cb);
if (unlikely(status || cb->cb_seq_status))
return status;
- }
+ } else
+ return -EINVAL;
return decode_cb_op_status(xdr, OP_CB_RECALL, &cb->cb_status);
}
@@ -608,7 +609,9 @@ static int nfs4_xdr_dec_cb_layout(struct rpc_rqst *rqstp,
status = decode_cb_sequence4res(xdr, cb);
if (unlikely(status || cb->cb_seq_status))
return status;
- }
+ } else
+ return -EINVAL;
+
return decode_cb_op_status(xdr, OP_CB_LAYOUTRECALL, &cb->cb_status);
}
#endif /* CONFIG_NFSD_PNFS */
@@ -667,7 +670,9 @@ static int nfs4_xdr_dec_cb_notify_lock(struct rpc_rqst *rqstp,
status = decode_cb_sequence4res(xdr, cb);
if (unlikely(status || cb->cb_seq_status))
return status;
- }
+ } else
+ return -EINVAL;
+
return decode_cb_op_status(xdr, OP_CB_NOTIFY_LOCK, &cb->cb_status);
}
--
2.17.0
next reply other threads:[~2019-07-24 8:28 UTC|newest]
Thread overview: 3+ messages / expand[flat|nested] mbox.gz Atom feed top
2019-07-24 8:28 Jia-Ju Bai [this message]
2019-07-30 23:03 ` [PATCH] fs: nfsd: Fix three possible null-pointer dereferences J. Bruce Fields
2019-07-30 23:08 ` J. Bruce Fields
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