diff options
author | Trond Myklebust <trond.myklebust@hammerspace.com> | 2018-12-01 23:18:00 -0500 |
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committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2018-12-21 14:15:17 +0100 |
commit | 20595815b058dc7d7ae9d16169e20407f71be2d6 (patch) | |
tree | 0b6289c29dec3e5a9e7dba0f9b0c09fa0f084b44 | |
parent | de956d40781191903c7eb8e6843b0cb506ab1f43 (diff) |
SUNRPC: Fix a potential race in xprt_connect()
[ Upstream commit 0a9a4304f3614e25d9de9b63502ca633c01c0d70 ]
If an asynchronous connection attempt completes while another task is
in xprt_connect(), then the call to rpc_sleep_on() could end up
racing with the call to xprt_wake_pending_tasks().
So add a second test of the connection state after we've put the
task to sleep and set the XPRT_CONNECTING flag, when we know that there
can be no asynchronous connection attempts still in progress.
Fixes: 0b9e79431377d ("SUNRPC: Move the test for XPRT_CONNECTING into...")
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
-rw-r--r-- | net/sunrpc/xprt.c | 11 |
1 files changed, 9 insertions, 2 deletions
diff --git a/net/sunrpc/xprt.c b/net/sunrpc/xprt.c index a8db2e3f8904..d066aae3cb6d 100644 --- a/net/sunrpc/xprt.c +++ b/net/sunrpc/xprt.c @@ -781,8 +781,15 @@ void xprt_connect(struct rpc_task *task) return; if (xprt_test_and_set_connecting(xprt)) return; - xprt->stat.connect_start = jiffies; - xprt->ops->connect(xprt, task); + /* Race breaker */ + if (!xprt_connected(xprt)) { + xprt->stat.connect_start = jiffies; + xprt->ops->connect(xprt, task); + } else { + xprt_clear_connecting(xprt); + task->tk_status = 0; + rpc_wake_up_queued_task(&xprt->pending, task); + } } xprt_release_write(xprt, task); } |