[patch 13/41] nfsd: only set file_lock.fl_lmops in nfsd4_lockt ifa stateowner is found
From: Greg KH
Date: Wed Feb 04 2009 - 13:56:28 EST
2.6.27-stable review patch. If anyone has any objections, please let us know.
------------------
From: Jeff Layton <jlayton@xxxxxxxxxx>
commit fa82a491275a613b15489aab4b99acecb00958d3 upstream.
nfsd4_lockt does a search for a lockstateowner when building the lock
struct to test. If one is found, it'll set fl_owner to it. Regardless of
whether that happens, it'll also set fl_lmops. Given that this lock is
basically a "lightweight" lock that's just used for checking conflicts,
setting fl_lmops is probably not appropriate for it.
This behavior exposed a bug in DLM's GETLK implementation where it
wasn't clearing out the fields in the file_lock before filling in
conflicting lock info. While we were able to fix this in DLM, it
still seems pointless and dangerous to set the fl_lmops this way
when we may have a NULL lockstateowner.
Signed-off-by: Jeff Layton <jlayton@xxxxxxxxxx>
Signed-off-by: J. Bruce Fields <bfields@xxxxxxxxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxx>
---
fs/nfsd/nfs4state.c | 1 -
1 file changed, 1 deletion(-)
--- a/fs/nfsd/nfs4state.c
+++ b/fs/nfsd/nfs4state.c
@@ -2840,7 +2840,6 @@ nfsd4_lockt(struct svc_rqst *rqstp, stru
file_lock.fl_owner = (fl_owner_t)lockt->lt_stateowner;
file_lock.fl_pid = current->tgid;
file_lock.fl_flags = FL_POSIX;
- file_lock.fl_lmops = &nfsd_posix_mng_ops;
file_lock.fl_start = lockt->lt_offset;
if ((lockt->lt_length == ~(u64)0) || LOFF_OVERFLOW(lockt->lt_offset, lockt->lt_length))
--
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