NeilBrown f9e1aedc6c sunrpc/cache: remove races with queuing an upcall. ... We currently queue an upcall after setting CACHE_PENDING, and dequeue after clearing CACHE_PENDING. So a request should only be present when CACHE_PENDING is set. However we don't combine the test and the enqueue/dequeue in a protected region, so it is possible (if unlikely) for a race to result in a request being queued without CACHE_PENDING set, or a request to be absent despite CACHE_PENDING. So: include a test for CACHE_PENDING inside the regions of enqueue and dequeue where queue_lock is held, and abort the operation if the value is not as expected. Also remove the early 'return' from cache_dequeue() to ensure that it always removes all entries: As there is no locking between setting CACHE_PENDING and calling sunrpc_cache_pipe_upcall it is not inconceivable for some other thread to clear CACHE_PENDING and then someone else to set it and call sunrpc_cache_pipe_upcall, both before the original threads completed the call. With this, it perfectly safe and correct to: - call cache_dequeue() if and only if we have just cleared CACHE_PENDING - call sunrpc_cache_pipe_upcall() (via cache_make_upcall) if and only if we have just set CACHE_PENDING. Reported-by: Bodo Stroesser <bstroesser@ts.fujitsu.com> Signed-off-by: NeilBrown <neilb@suse.de> Signed-off-by: Bodo Stroesser <bstroesser@ts.fujitsu.com> Signed-off-by: J. Bruce Fields <bfields@redhat.com>		2013-07-01 17:42:53 -04:00
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auth_gss	svcrpc: store gss mech in svc_cred	2013-07-01 17:23:06 -04:00
xprtrdma
addr.c
auth_generic.c
auth_null.c
auth_unix.c
auth.c
backchannel_rqst.c
bc_svc.c
cache.c	sunrpc/cache: remove races with queuing an upcall.	2013-07-01 17:42:53 -04:00
clnt.c
Kconfig
Makefile
netns.h
rpc_pipe.c
rpcb_clnt.c
sched.c
socklib.c
stats.c
sunrpc_syms.c
sunrpc.h
svc_xprt.c
svc.c
svcauth_unix.c
svcauth.c
svcsock.c	svcrpc: don't error out on small tcp fragment	2013-07-01 17:32:04 -04:00
sysctl.c
timer.c
xdr.c
xprt.c
xprtsock.c