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Subject: [PATCH net 1/9] rxrpc: Fix missing unlock in rxrpc_do_sendmsg()
From:   David Howells <dhowells@redhat.com>
To:     netdev@vger.kernel.org
Cc:     Marc Dionne <marc.dionne@auristor.com>,
        linux-afs@lists.infradead.org, dhowells@redhat.com,
        linux-afs@lists.infradead.org, linux-kernel@vger.kernel.org
Date:   Thu, 15 Dec 2022 16:19:47 +0000
Message-ID: <167112118790.152641.2918682447555593225.stgit@warthog.procyon.org.uk>
In-Reply-To: <167112117887.152641.6194213035340041732.stgit@warthog.procyon.org.uk>
References: <167112117887.152641.6194213035340041732.stgit@warthog.procyon.org.uk>
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One of the error paths in rxrpc_do_sendmsg() doesn't unlock the call mutex
before returning.  Fix it to do this.

Note that this still doesn't get rid of the checker warning:

   ../net/rxrpc/sendmsg.c:617:5: warning: context imbalance in 'rxrpc_do_sendmsg' - wrong count at exit

I think the interplay between the socket lock and the call's user_mutex may
be too complicated for checker to analyse, especially as
rxrpc_new_client_call_for_sendmsg(), which it calls, returns with the
call's user_mutex if successful but unconditionally drops the socket lock.

Fixes: e754eba685aa ("rxrpc: Provide a cmsg to specify the amount of Tx data for a call")
Signed-off-by: David Howells <dhowells@redhat.com>
cc: Marc Dionne <marc.dionne@auristor.com>
cc: linux-afs@lists.infradead.org
---

 net/rxrpc/sendmsg.c |    2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/net/rxrpc/sendmsg.c b/net/rxrpc/sendmsg.c
index 9fa7e37f7155..cde1e65f16b4 100644
--- a/net/rxrpc/sendmsg.c
+++ b/net/rxrpc/sendmsg.c
@@ -625,7 +625,7 @@ int rxrpc_do_sendmsg(struct rxrpc_sock *rx, struct msghdr *msg, size_t len)
 			if (call->tx_total_len != -1 ||
 			    call->tx_pending ||
 			    call->tx_top != 0)
-				goto error_put;
+				goto out_put_unlock;
 			call->tx_total_len = p.call.tx_total_len;
 		}
 	}