NFSv4.2: condition READDIR's mask for security label based on LSM state (05ad9175) · Commits · 戴 / test

Currently, the client will always ask for security_labels if the server returns that it supports that feature regardless of any LSM modules (such as Selinux) enforcing security policy. This adds performance penalty to the READDIR operation. Client adjusts superblock's support of the security_label based on the server's support but also current client's configuration of the LSM modules. Thus, prior to using the default bitmask in READDIR, this patch checks the server's capabilities and then instructs READDIR to remove FATTR4_WORD2_SECURITY_LABEL from the bitmask. v5: fixing silly mistakes of the rushed v4 v4: simplifying logic v3: changing label's initialization per Ondrej's comment v2: dropping selinux hook and using the sb cap. Suggested-by:

Ondrej Mosnacek <omosnace@redhat.com> Suggested-by:

Scott Mayhew <smayhew@redhat.com> Signed-off-by:

Olga Kornievskaia <kolga@netapp.com> Fixes: ("VFS: normal filesystems (and lustre): d_inode() annotations") Signed-off-by:

Trond Myklebust <trond.myklebust@hammerspace.com>

fs/nfs/nfs4proc.c

+8 −2

Original line number	Diff line number	Diff line
		@@ -4965,12 +4965,12 @@ static int _nfs4_proc_readdir(struct dentry dentry, const struct cred cred,
		u64 cookie, struct page **pages, unsigned int count, bool plus)
		{
		struct inode *dir = d_inode(dentry);
		struct nfs_server *server = NFS_SERVER(dir);
		struct nfs4_readdir_arg args = {
		.fh = NFS_FH(dir),
		.pages = pages,
		.pgbase = 0,
		.count = count,
		.bitmask = NFS_SERVER(d_inode(dentry))->attr_bitmask,
		.plus = plus,
		};
		struct nfs4_readdir_res res;
		@@ -4985,9 +4985,15 @@ static int _nfs4_proc_readdir(struct dentry dentry, const struct cred cred,
		dprintk("%s: dentry = %pd2, cookie = %Lu\n", __func__,
		dentry,
		(unsigned long long)cookie);
		if (!(server->caps & NFS_CAP_SECURITY_LABEL))
		args.bitmask = server->attr_bitmask_nl;
		else
		args.bitmask = server->attr_bitmask;

		nfs4_setup_readdir(cookie, NFS_I(dir)->cookieverf, dentry, &args);
		res.pgbase = args.pgbase;
		status = nfs4_call_sync(NFS_SERVER(dir)->client, NFS_SERVER(dir), &msg, &args.seq_args, &res.seq_res, 0);
		status = nfs4_call_sync(server->client, server, &msg, &args.seq_args,
		&res.seq_res, 0);
		if (status >= 0) {
		memcpy(NFS_I(dir)->cookieverf, res.verifier.data, NFS4_VERIFIER_SIZE);
		status += args.pgbase;

Admin message