]> git.baikalelectronics.ru Git - kernel.git/commit
SUNRPC: Ensure we release the socket write lock if the rpc_task exits early
authorTrond Myklebust <Trond.Myklebust@netapp.com>
Mon, 7 Jan 2013 19:30:46 +0000 (14:30 -0500)
committerTrond Myklebust <Trond.Myklebust@netapp.com>
Tue, 8 Jan 2013 19:30:43 +0000 (14:30 -0500)
commitfc24d5a6601c4cedc71145e6f263c875ee770b45
tree8bd92625c340176d92ab0b77c0617bffd20a97eb
parent7250e9080349dd83b03f810789827ee067924755
SUNRPC: Ensure we release the socket write lock if the rpc_task exits early

If the rpc_task exits while holding the socket write lock before it has
allocated an rpc slot, then the usual mechanism for releasing the write
lock in xprt_release() is defeated.

The problem occurs if the call to xprt_lock_write() initially fails, so
that the rpc_task is put on the xprt->sending wait queue. If the task
exits after being assigned the lock by __xprt_lock_write_func, but
before it has retried the call to xprt_lock_and_alloc_slot(), then
it calls xprt_release() while holding the write lock, but will
immediately exit due to the test for task->tk_rqstp != NULL.

Reported-by: Chris Perl <chris.perl@gmail.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
Cc: stable@vger.kernel.org [>= 3.1]
net/sunrpc/sched.c
net/sunrpc/xprt.c