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@suse.de> Cc: stable@kernel.org Signed-off-by: J. Bruce Fields <bfields@redhat.com>
		
			
				
	
	
		
			79 lines
		
	
	
	
		
			1.7 KiB
			
		
	
	
	
		
			C
		
	
	
	
	
	
			
		
		
	
	
			79 lines
		
	
	
	
		
			1.7 KiB
			
		
	
	
	
		
			C
		
	
	
	
	
	
/*
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 * This file contains all the stubs needed when communicating with lockd.
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 * This level of indirection is necessary so we can run nfsd+lockd without
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 * requiring the nfs client to be compiled in/loaded, and vice versa.
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 *
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 * Copyright (C) 1996, Olaf Kirch <okir@monad.swb.de>
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 */
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#include <linux/file.h>
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#include <linux/lockd/bind.h>
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#include "nfsd.h"
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#include "vfs.h"
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#define NFSDDBG_FACILITY		NFSDDBG_LOCKD
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#ifdef CONFIG_LOCKD_V4
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#define nlm_stale_fh	nlm4_stale_fh
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#define nlm_failed	nlm4_failed
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#else
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#define nlm_stale_fh	nlm_lck_denied_nolocks
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#define nlm_failed	nlm_lck_denied_nolocks
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#endif
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/*
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 * Note: we hold the dentry use count while the file is open.
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 */
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static __be32
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nlm_fopen(struct svc_rqst *rqstp, struct nfs_fh *f, struct file **filp)
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{
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	__be32		nfserr;
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	struct svc_fh	fh;
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	/* must initialize before using! but maxsize doesn't matter */
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	fh_init(&fh,0);
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	fh.fh_handle.fh_size = f->size;
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	memcpy((char*)&fh.fh_handle.fh_base, f->data, f->size);
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	fh.fh_export = NULL;
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	exp_readlock();
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	nfserr = nfsd_open(rqstp, &fh, S_IFREG, NFSD_MAY_LOCK, filp);
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	fh_put(&fh);
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	exp_readunlock();
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 	/* We return nlm error codes as nlm doesn't know
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	 * about nfsd, but nfsd does know about nlm..
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	 */
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	switch (nfserr) {
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	case nfs_ok:
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		return 0;
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	case nfserr_dropit:
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		return nlm_drop_reply;
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	case nfserr_stale:
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		return nlm_stale_fh;
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	default:
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		return nlm_failed;
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	}
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}
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static void
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nlm_fclose(struct file *filp)
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{
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	fput(filp);
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}
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static struct nlmsvc_binding	nfsd_nlm_ops = {
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	.fopen		= nlm_fopen,		/* open file for locking */
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	.fclose		= nlm_fclose,		/* close file */
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};
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void
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nfsd_lockd_init(void)
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{
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	dprintk("nfsd: initializing lockd\n");
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	nlmsvc_ops = &nfsd_nlm_ops;
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}
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void
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nfsd_lockd_shutdown(void)
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{
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	nlmsvc_ops = NULL;
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}
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