Merge tag 'selinux-pr-20200330' of git://git.kernel.org/pub/scm/linux/kernel/git/pcmoore/selinux

Pull SELinux updates from Paul Moore:
 "We've got twenty SELinux patches for the v5.7 merge window, the
  highlights are below:

   - Deprecate setting /sys/fs/selinux/checkreqprot to 1.

     This flag was originally created to deal with legacy userspace and
     the READ_IMPLIES_EXEC personality flag. We changed the default from
     1 to 0 back in Linux v4.4 and now we are taking the next step of
     deprecating it, at some point in the future we will take the final
     step of rejecting 1.

   - Allow kernfs symlinks to inherit the SELinux label of the parent
     directory. In order to preserve backwards compatibility this is
     protected by the genfs_seclabel_symlinks SELinux policy capability.

   - Optimize how we store filename transitions in the kernel, resulting
     in some significant improvements to policy load times.

   - Do a better job calculating our internal hash table sizes which
     resulted in additional policy load improvements and likely general
     SELinux performance improvements as well.

   - Remove the unused initial SIDs (labels) and improve how we handle
     initial SIDs.

   - Enable per-file labeling for the bpf filesystem.

   - Ensure that we properly label NFS v4.2 filesystems to avoid a
     temporary unlabeled condition.

   - Add some missing XFS quota command types to the SELinux quota
     access controls.

   - Fix a problem where we were not updating the seq_file position
     index correctly in selinuxfs.

   - We consolidate some duplicated code into helper functions.

   - A number of list to array conversions.

   - Update Stephen Smalley's email address in MAINTAINERS"

* tag 'selinux-pr-20200330' of git://git.kernel.org/pub/scm/linux/kernel/git/pcmoore/selinux:
  selinux: clean up indentation issue with assignment statement
  NFS: Ensure security label is set for root inode
  MAINTAINERS: Update my email address
  selinux: avtab_init() and cond_policydb_init() return void
  selinux: clean up error path in policydb_init()
  selinux: remove unused initial SIDs and improve handling
  selinux: reduce the use of hard-coded hash sizes
  selinux: Add xfs quota command types
  selinux: optimize storage of filename transitions
  selinux: factor out loop body from filename_trans_read()
  security: selinux: allow per-file labeling for bpffs
  selinux: generalize evaluate_cond_node()
  selinux: convert cond_expr to array
  selinux: convert cond_av_list to array
  selinux: convert cond_list to array
  selinux: sel_avc_get_stat_idx should increase position index
  selinux: allow kernfs symlinks to inherit parent directory context
  selinux: simplify evaluate_cond_node()
  Documentation,selinux: deprecate setting checkreqprot to 1
  selinux: move status variables out of selinux_ss

Author: torvalds

Documentation/ABI/obsolete/sysfs-selinux-checkreqprot

@@ -0,0 +1,23 @@
+What:		/sys/fs/selinux/checkreqprot
+Date:		April 2005 (predates git)
+KernelVersion:	2.6.12-rc2 (predates git)
+Contact:	[email protected]
+Description:
+
+	The selinuxfs "checkreqprot" node allows SELinux to be configured
+	to check the protection requested by userspace for mmap/mprotect
+	calls instead of the actual protection applied by the kernel.
+	This was a compatibility mechanism for legacy userspace and
+	for the READ_IMPLIES_EXEC personality flag.  However, if set to
+	1, it weakens security by allowing mappings to be made executable
+	without authorization by policy.  The default value of checkreqprot
+	at boot was changed starting in Linux v4.4 to 0 (i.e. check the
+	actual protection), and Android and Linux distributions have been
+	explicitly writing a "0" to /sys/fs/selinux/checkreqprot during
+	initialization for some time.  Support for setting checkreqprot to 1
+	will be	removed in a future kernel release, at which point the kernel
+	will always cease using checkreqprot internally and will always
+	check the actual protections being applied upon mmap/mprotect calls.
+	The checkreqprot selinuxfs node will remain for backward compatibility
+	but will discard writes of the "0" value and will reject writes of the
+	"1" value when this mechanism is removed.

Documentation/admin-guide/kernel-parameters.txt

@@ -525,6 +525,7 @@
 			Default value is set via a kernel config option.
 			Value can be changed at runtime via
 				/sys/fs/selinux/checkreqprot.
+			Setting checkreqprot to 1 is deprecated.
 
 	cio_ignore=	[S390]
 			See Documentation/s390/common_io.rst for details.

MAINTAINERS

@@ -15027,7 +15027,7 @@ X:	security/selinux/
 
 SELINUX SECURITY MODULE
 M:	Paul Moore <[email protected]>
-M:	Stephen Smalley <[email protected]>
+M:	Stephen Smalley <[email protected]>
 M:	Eric Paris <[email protected]>
 L:	[email protected]
 W:	https://selinuxproject.org
@@ -15039,6 +15039,7 @@ F:	security/selinux/
 F:	scripts/selinux/
 F:	Documentation/admin-guide/LSM/SELinux.rst
 F:	Documentation/ABI/obsolete/sysfs-selinux-disable
+F:	Documentation/ABI/obsolete/sysfs-selinux-checkreqprot
 
 SENSABLE PHANTOM
 M:	Jiri Slaby <[email protected]>

fs/nfs/getroot.c

@@ -73,6 +73,7 @@ int nfs_get_root(struct super_block *s, struct fs_context *fc)
 	struct inode *inode;
 	char *name;
 	int error = -ENOMEM;
+	unsigned long kflags = 0, kflags_out = 0;
 
 	name = kstrdup(fc->source, GFP_KERNEL);
 	if (!name)
@@ -83,24 +84,27 @@ int nfs_get_root(struct super_block *s, struct fs_context *fc)
 	if (fsinfo.fattr == NULL)
 		goto out_name;
 
+	fsinfo.fattr->label = nfs4_label_alloc(server, GFP_KERNEL);
+	if (IS_ERR(fsinfo.fattr->label))
+		goto out_fattr;
 	error = server->nfs_client->rpc_ops->getroot(server, ctx->mntfh, &fsinfo);
 	if (error < 0) {
 		dprintk("nfs_get_root: getattr error = %d\n", -error);
 		nfs_errorf(fc, "NFS: Couldn't getattr on root");
-		goto out_fattr;
+		goto out_label;
 	}
 
 	inode = nfs_fhget(s, ctx->mntfh, fsinfo.fattr, NULL);
 	if (IS_ERR(inode)) {
 		dprintk("nfs_get_root: get root inode failed\n");
 		error = PTR_ERR(inode);
 		nfs_errorf(fc, "NFS: Couldn't get root inode");
-		goto out_fattr;
+		goto out_label;
 	}
 
 	error = nfs_superblock_set_dummy_root(s, inode);
 	if (error != 0)
-		goto out_fattr;
+		goto out_label;
 
 	/* root dentries normally start off anonymous and get spliced in later
 	 * if the dentry tree reaches them; however if the dentry already
@@ -111,7 +115,7 @@ int nfs_get_root(struct super_block *s, struct fs_context *fc)
 		dprintk("nfs_get_root: get root dentry failed\n");
 		error = PTR_ERR(root);
 		nfs_errorf(fc, "NFS: Couldn't get root dentry");
-		goto out_fattr;
+		goto out_label;
 	}
 
 	security_d_instantiate(root, inode);
@@ -123,12 +127,39 @@ int nfs_get_root(struct super_block *s, struct fs_context *fc)
 	}
 	spin_unlock(&root->d_lock);
 	fc->root = root;
+	if (NFS_SB(s)->caps & NFS_CAP_SECURITY_LABEL)
+		kflags |= SECURITY_LSM_NATIVE_LABELS;
+	if (ctx->clone_data.sb) {
+		if (d_inode(fc->root)->i_fop != &nfs_dir_operations) {
+			error = -ESTALE;
+			goto error_splat_root;
+		}
+		/* clone lsm security options from the parent to the new sb */
+		error = security_sb_clone_mnt_opts(ctx->clone_data.sb,
+						   s, kflags, &kflags_out);
+	} else {
+		error = security_sb_set_mnt_opts(s, fc->security,
+							kflags, &kflags_out);
+	}
+	if (error)
+		goto error_splat_root;
+	if (NFS_SB(s)->caps & NFS_CAP_SECURITY_LABEL &&
+		!(kflags_out & SECURITY_LSM_NATIVE_LABELS))
+		NFS_SB(s)->caps &= ~NFS_CAP_SECURITY_LABEL;
+
+	nfs_setsecurity(inode, fsinfo.fattr, fsinfo.fattr->label);
 	error = 0;
 
+out_label:
+	nfs4_label_free(fsinfo.fattr->label);
 out_fattr:
 	nfs_free_fattr(fsinfo.fattr);
 out_name:
 	kfree(name);
 out:
 	return error;
+error_splat_root:
+	dput(fc->root);
+	fc->root = NULL;
+	goto out_label;
 }

fs/nfs/nfs4proc.c

@@ -4002,31 +4002,25 @@ static int nfs4_proc_get_root(struct nfs_server *server, struct nfs_fh *mntfh,
 {
 	int error;
 	struct nfs_fattr *fattr = info->fattr;
-	struct nfs4_label *label = NULL;
+	struct nfs4_label *label = fattr->label;
 
 	error = nfs4_server_capabilities(server, mntfh);
 	if (error < 0) {
 		dprintk("nfs4_get_root: getcaps error = %d\n", -error);
 		return error;
 	}
 
-	label = nfs4_label_alloc(server, GFP_KERNEL);
-	if (IS_ERR(label))
-		return PTR_ERR(label);
-
 	error = nfs4_proc_getattr(server, mntfh, fattr, label, NULL);
 	if (error < 0) {
 		dprintk("nfs4_get_root: getattr error = %d\n", -error);
-		goto err_free_label;
+		goto out;
 	}
 
 	if (fattr->valid & NFS_ATTR_FATTR_FSID &&
 	    !nfs_fsid_equal(&server->fsid, &fattr->fsid))
 		memcpy(&server->fsid, &fattr->fsid, sizeof(server->fsid));
 
-err_free_label:
-	nfs4_label_free(label);
-
+out:
 	return error;
 }
 

fs/nfs/super.c

@@ -1179,7 +1179,6 @@ int nfs_get_tree_common(struct fs_context *fc)
 	struct super_block *s;
 	int (*compare_super)(struct super_block *, struct fs_context *) = nfs_compare_super;
 	struct nfs_server *server = ctx->server;
-	unsigned long kflags = 0, kflags_out = 0;
 	int error;
 
 	ctx->server = NULL;
@@ -1239,26 +1238,6 @@ int nfs_get_tree_common(struct fs_context *fc)
 		goto error_splat_super;
 	}
 
-	if (NFS_SB(s)->caps & NFS_CAP_SECURITY_LABEL)
-		kflags |= SECURITY_LSM_NATIVE_LABELS;
-	if (ctx->clone_data.sb) {
-		if (d_inode(fc->root)->i_fop != &nfs_dir_operations) {
-			error = -ESTALE;
-			goto error_splat_root;
-		}
-		/* clone any lsm security options from the parent to the new sb */
-		error = security_sb_clone_mnt_opts(ctx->clone_data.sb, s, kflags,
-				&kflags_out);
-	} else {
-		error = security_sb_set_mnt_opts(s, fc->security,
-							kflags, &kflags_out);
-	}
-	if (error)
-		goto error_splat_root;
-	if (NFS_SB(s)->caps & NFS_CAP_SECURITY_LABEL &&
-		!(kflags_out & SECURITY_LSM_NATIVE_LABELS))
-		NFS_SB(s)->caps &= ~NFS_CAP_SECURITY_LABEL;
-
 	s->s_flags |= SB_ACTIVE;
 	error = 0;
 
@@ -1268,10 +1247,6 @@ int nfs_get_tree_common(struct fs_context *fc)
 out_err_nosb:
 	nfs_free_server(server);
 	goto out;
-
-error_splat_root:
-	dput(fc->root);
-	fc->root = NULL;
 error_splat_super:
 	deactivate_locked_super(s);
 	goto out;

include/linux/nfs_xdr.h

@@ -75,6 +75,7 @@ struct nfs_fattr {
 	struct nfs4_string	*owner_name;
 	struct nfs4_string	*group_name;
 	struct nfs4_threshold	*mdsthreshold;	/* pNFS threshold hints */
+	struct nfs4_label	*label;
 };
 
 #define NFS_ATTR_FATTR_TYPE		(1U << 0)

scripts/selinux/genheaders/genheaders.c

@@ -67,8 +67,12 @@ int main(int argc, char *argv[])
 	}
 
 	isids_len = sizeof(initial_sid_to_string) / sizeof (char *);
-	for (i = 1; i < isids_len; i++)
-		initial_sid_to_string[i] = stoupperx(initial_sid_to_string[i]);
+	for (i = 1; i < isids_len; i++) {
+		const char *s = initial_sid_to_string[i];
+
+		if (s)
+			initial_sid_to_string[i] = stoupperx(s);
+	}
 
 	fprintf(fout, "/* This file is automatically generated.  Do not edit. */\n");
 	fprintf(fout, "#ifndef _SELINUX_FLASK_H_\n#define _SELINUX_FLASK_H_\n\n");
@@ -82,7 +86,8 @@ int main(int argc, char *argv[])
 
 	for (i = 1; i < isids_len; i++) {
 		const char *s = initial_sid_to_string[i];
-		fprintf(fout, "#define SECINITSID_%-39s %2d\n", s, i);
+		if (s)
+			fprintf(fout, "#define SECINITSID_%-39s %2d\n", s, i);
 	}
 	fprintf(fout, "\n#define SECINITSID_NUM %d\n", i-1);
 	fprintf(fout, "\nstatic inline bool security_is_socket_class(u16 kern_tclass)\n");

security/selinux/Kconfig

@@ -88,6 +88,9 @@ config SECURITY_SELINUX_CHECKREQPROT_VALUE
 	  'checkreqprot=' boot parameter.  It may also be changed at runtime
 	  via /sys/fs/selinux/checkreqprot if authorized by policy.
 
+	  WARNING: this option is deprecated and will be removed in a future
+	  kernel release.
+
 	  If you are unsure how to answer this question, answer 0.
 
 config SECURITY_SELINUX_SIDTAB_HASH_BITS

security/selinux/Makefile

@@ -6,9 +6,9 @@
 obj-$(CONFIG_SECURITY_SELINUX) := selinux.o
 
 selinux-y := avc.o hooks.o selinuxfs.o netlink.o nlmsgtab.o netif.o \
-	     netnode.o netport.o \
+	     netnode.o netport.o status.o \
 	     ss/ebitmap.o ss/hashtab.o ss/symtab.o ss/sidtab.o ss/avtab.o \
-	     ss/policydb.o ss/services.o ss/conditional.o ss/mls.o ss/status.o
+	     ss/policydb.o ss/services.o ss/conditional.o ss/mls.o
 
 selinux-$(CONFIG_SECURITY_NETWORK_XFRM) += xfrm.o