[66/74] nfsd: fix auth_domain reference leak on nlm operations

From: Greg KH
Date: Wed Apr 13 2011 - 11:58:25 EST

2.6.32-longterm review patch. If anyone has any objections, please let us know.


From: J. Bruce Fields <bfields@xxxxxxxxxx>

commit 954032d2527f2fce7355ba70709b5e143d6b686f upstream.

This was noticed by users who performed more than 2^32 lock operations
and hence made this counter overflow (eventually leading to
use-after-free's). Setting rq_client to NULL here means that it won't
later get auth_domain_put() when it should be.

Appears to have been introduced in 2.5.42 by "[PATCH] kNFSd: Move auth
domain lookup into svcauth" which moved most of the rq_client handling
to common svcauth code, but left behind this one line.

Cc: Neil Brown <neilb@xxxxxxx>
Signed-off-by: J. Bruce Fields <bfields@xxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxx>

fs/nfsd/lockd.c | 1 -
1 file changed, 1 deletion(-)

--- a/fs/nfsd/lockd.c
+++ b/fs/nfsd/lockd.c
@@ -44,7 +44,6 @@ nlm_fopen(struct svc_rqst *rqstp, struct
nfserr = nfsd_open(rqstp, &fh, S_IFREG, NFSD_MAY_LOCK, filp);
- rqstp->rq_client = NULL;
/* We return nlm error codes as nlm doesn't know
* about nfsd, but nfsd does know about nlm..

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