[PATCH] [46/106] nfsd: fix auth_domain reference leak on nlm operations

[Andi Kleen]

2.6.35-longterm review patch.  If anyone has any objections, please let me 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>
Signed-off-by: Andi Kleen <ak@xxxxxxxxxxxxxxx>

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

Index: linux-2.6.35.y/fs/nfsd/lockd.c
===================================================================
--- linux-2.6.35.y.orig/fs/nfsd/lockd.c
+++ linux-2.6.35.y/fs/nfsd/lockd.c
@@ -38,7 +38,6 @@ nlm_fopen(struct svc_rqst *rqstp, struct
 	exp_readlock();
 	nfserr = nfsd_open(rqstp, &fh, S_IFREG, NFSD_MAY_LOCK, filp);
 	fh_put(&fh);
-	rqstp->rq_client = NULL;
 	exp_readunlock();
  	/* We return nlm error codes as nlm doesn't know
 	 * about nfsd, but nfsd does know about nlm..
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/