Commit 7e6a72e5 authored by Christoph Hellwig's avatar Christoph Hellwig Committed by J. Bruce Fields
Browse files

nfsd: fix file access refcount leak when nfsd4_truncate fails 



nfsd4_process_open2 will currently will get access to the file, and then
call nfsd4_truncate to (possibly) truncate it. If that operation fails
though, then the access references will never be released as the
nfs4_ol_stateid is never initialized.

Fix by moving the nfsd4_truncate call into nfs4_get_vfs_file, ensuring
that the refcounts are properly put if the truncate fails.

Signed-off-by: default avatarJeff Layton <jlayton@primarydata.com>
Signed-off-by: default avatarChristoph Hellwig <hch@infradead.org>
Signed-off-by: default avatarJ. Bruce Fields <bfields@redhat.com>
parent 1055414f

fs/nfsd/nfs4state.c

+30 −32
Original line number Diff line number Diff line
@@ -3046,6 +3046,21 @@ static inline int nfs4_access_to_access(u32 nfs4_access) 
	return flags;

}



static inline __be32

nfsd4_truncate(struct svc_rqst *rqstp, struct svc_fh *fh,

		struct nfsd4_open *open)

{

	struct iattr iattr = {

		.ia_valid = ATTR_SIZE,

		.ia_size = 0,

	};

	if (!open->op_truncate)

		return 0;

	if (!(open->op_share_access & NFS4_SHARE_ACCESS_WRITE))

		return nfserr_inval;

	return nfsd_setattr(rqstp, fh, &iattr, 0, (time_t)0);

}



static __be32 nfs4_get_vfs_file(struct svc_rqst *rqstp, struct nfs4_file *fp,

		struct svc_fh *cur_fh, struct nfsd4_open *open)

{
@@ -3057,53 +3072,39 @@ static __be32 nfs4_get_vfs_file(struct svc_rqst *rqstp, struct nfs4_file *fp, 
		status = nfsd_open(rqstp, cur_fh, S_IFREG, access,

			&fp->fi_fds[oflag]);

		if (status)

			return status;

			goto out;

	}

	nfs4_file_get_access(fp, oflag);



	status = nfsd4_truncate(rqstp, cur_fh, open);

	if (status)

		goto out_put_access;



	return nfs_ok;

}



static inline __be32

nfsd4_truncate(struct svc_rqst *rqstp, struct svc_fh *fh,

		struct nfsd4_open *open)

{

	struct iattr iattr = {

		.ia_valid = ATTR_SIZE,

		.ia_size = 0,

	};

	if (!open->op_truncate)

		return 0;

	if (!(open->op_share_access & NFS4_SHARE_ACCESS_WRITE))

		return nfserr_inval;

	return nfsd_setattr(rqstp, fh, &iattr, 0, (time_t)0);

out_put_access:

	nfs4_file_put_access(fp, oflag);

out:

	return status;

}



static __be32

nfs4_upgrade_open(struct svc_rqst *rqstp, struct nfs4_file *fp, struct svc_fh *cur_fh, struct nfs4_ol_stateid *stp, struct nfsd4_open *open)

{

	u32 op_share_access = open->op_share_access;

	bool new_access;

	__be32 status;



	new_access = !test_access(op_share_access, stp);

	if (new_access) {

	if (!test_access(op_share_access, stp))

		status = nfs4_get_vfs_file(rqstp, fp, cur_fh, open);

		if (status)

			return status;

	}

	else

		status = nfsd4_truncate(rqstp, cur_fh, open);

	if (status) {

		if (new_access) {

			int oflag = nfs4_access_to_omode(op_share_access);

			nfs4_file_put_access(fp, oflag);

		}



	if (status)

		return status;

	}



	/* remember the open */

	set_access(op_share_access, stp);

	set_deny(open->op_share_deny, stp);



	return nfs_ok;

}
@@ -3352,9 +3353,6 @@ nfsd4_process_open2(struct svc_rqst *rqstp, struct svc_fh *current_fh, struct nf 
			goto out;

	} else {

		status = nfs4_get_vfs_file(rqstp, fp, current_fh, open);

		if (status)

			goto out;

		status = nfsd4_truncate(rqstp, current_fh, open);

		if (status)

			goto out;

		stp = open->op_stp;

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