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From:   trondmy@kernel.org
To:     Anna Schumaker <anna.schumaker@netapp.com>
Cc:     Russell Cattelan <cattelan@thebarn.com>,
        Chuck Lever <chuck.lever@oracle.com>,
        Jeff Layton <jlayton@kernel.org>, linux-nfs@vger.kernel.org
Subject: [PATCH] Revert "SUNRPC: Fail faster on bad verifier"
Date:   Tue,  5 Sep 2023 21:03:28 -0400
Message-ID: <20230906010328.54634-1-trondmy@kernel.org>
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From: Trond Myklebust <trond.myklebust@hammerspace.com>

This reverts commit 0701214cd6e66585a999b132eb72ae0489beb724.

The premise of this commit was incorrect. There are exactly 2 cases
where rpcauth_checkverf() will return an error:

1) If there was an XDR decode problem (i.e. garbage data).
2) If gss_validate() had a problem verifying the RPCSEC_GSS MIC.

In the second case, there are again 2 subcases:

a) The GSS context expires, in which case gss_validate() will force a
   new context negotiation on retry by invalidating the cred.
b) The sequence number check failed because an RPC call timed out, and
   the client retransmitted the request using a new sequence number,
   as required by RFC2203.

In neither subcase is this a fatal error.

Reported-by: Russell Cattelan <cattelan@thebarn.com>
Fixes: 0701214cd6e6 ("SUNRPC: Fail faster on bad verifier")
Cc: stable@vger.kernel.org
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
---
 net/sunrpc/clnt.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/net/sunrpc/clnt.c b/net/sunrpc/clnt.c
index 12c46e129db8..5a7de7e55548 100644
--- a/net/sunrpc/clnt.c
+++ b/net/sunrpc/clnt.c
@@ -2724,7 +2724,7 @@ rpc_decode_header(struct rpc_task *task, struct xdr_stream *xdr)
 
 out_verifier:
 	trace_rpc_bad_verifier(task);
-	goto out_err;
+	goto out_garbage;
 
 out_msg_denied:
 	error = -EACCES;
-- 
2.41.0