Merge branch 'work.mount' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs

Pull vfs mount infrastructure updates from Al Viro:
 "The rest of core infrastructure; no new syscalls in that pile, but the
  old parts are switched to new infrastructure. At that point
  conversions of individual filesystems can happen independently; some
  are done here (afs, cgroup, procfs, etc.), there's also a large series
  outside of that pile dealing with NFS (quite a bit of option-parsing
  stuff is getting used there - it's one of the most convoluted
  filesystems in terms of mount-related logics), but NFS bits are the
  next cycle fodder.

  It got seriously simplified since the last cycle; documentation is
  probably the weakest bit at the moment - I considered dropping the
  commit introducing Documentation/filesystems/mount_api.txt (cutting
  the size increase by quarter ;-), but decided that it would be better
  to fix it up after -rc1 instead.

  That pile allows to do followup work in independent branches, which
  should make life much easier for the next cycle. fs/super.c size
  increase is unpleasant; there's a followup series that allows to
  shrink it considerably, but I decided to leave that until the next
  cycle"

* 'work.mount' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs: (41 commits)
  afs: Use fs_context to pass parameters over automount
  afs: Add fs_context support
  vfs: Add some logging to the core users of the fs_context log
  vfs: Implement logging through fs_context
  vfs: Provide documentation for new mount API
  vfs: Remove kern_mount_data()
  hugetlbfs: Convert to fs_context
  cpuset: Use fs_context
  kernfs, sysfs, cgroup, intel_rdt: Support fs_context
  cgroup: store a reference to cgroup_ns into cgroup_fs_context
  cgroup1_get_tree(): separate "get cgroup_root to use" into a separate helper
  cgroup_do_mount(): massage calling conventions
  cgroup: stash cgroup_root reference into cgroup_fs_context
  cgroup2: switch to option-by-option parsing
  cgroup1: switch to option-by-option parsing
  cgroup: take options parsing into ->parse_monolithic()
  cgroup: fold cgroup1_mount() into cgroup1_get_tree()
  cgroup: start switching to fs_context
  ipc: Convert mqueue fs to fs_context
  proc: Add fs_context support to procfs
  ...

2 files changed, 96 insertions, 15 deletions

diff --git a/security/smack/smack.h b/security/smack/smack.h
index 9c7c95a5c497..cf52af77d15e 100644
--- a/security/smack/smack.h
+++ b/security/smack/smack.h
@@ -196,22 +196,13 @@ struct smack_known_list_elem {
 
 enum {
 	Opt_error = -1,
-	Opt_fsdefault = 1,
-	Opt_fsfloor = 2,
-	Opt_fshat = 3,
-	Opt_fsroot = 4,
-	Opt_fstransmute = 5,
+	Opt_fsdefault = 0,
+	Opt_fsfloor = 1,
+	Opt_fshat = 2,
+	Opt_fsroot = 3,
+	Opt_fstransmute = 4,
 };
 
-/*
- * Mount options
- */
-#define SMK_FSDEFAULT	"smackfsdef="
-#define SMK_FSFLOOR	"smackfsfloor="
-#define SMK_FSHAT	"smackfshat="
-#define SMK_FSROOT	"smackfsroot="
-#define SMK_FSTRANS	"smackfstransmute="
-
 #define SMACK_DELETE_OPTION	"-DELETE"
 #define SMACK_CIPSO_OPTION 	"-CIPSO"
 
diff --git a/security/smack/smack_lsm.c b/security/smack/smack_lsm.c
index 424bce4ef21d..5c1613519d5a 100644
--- a/security/smack/smack_lsm.c
+++ b/security/smack/smack_lsm.c
@@ -43,6 +43,8 @@
 #include <linux/shm.h>
 #include <linux/binfmts.h>
 #include <linux/parser.h>
+#include <linux/fs_context.h>
+#include <linux/fs_parser.h>
 #include "smack.h"
 
 #define TRANS_TRUE	"TRUE"
@@ -526,7 +528,6 @@ static int smack_syslog(int typefrom_file)
 	return rc;
 }
 
-
 /*
  * Superblock Hooks.
  */
@@ -631,6 +632,92 @@ out_opt_err:
 	return -EINVAL;
 }
 
+/**
+ * smack_fs_context_dup - Duplicate the security data on fs_context duplication
+ * @fc: The new filesystem context.
+ * @src_fc: The source filesystem context being duplicated.
+ *
+ * Returns 0 on success or -ENOMEM on error.
+ */
+static int smack_fs_context_dup(struct fs_context *fc,
+				struct fs_context *src_fc)
+{
+	struct smack_mnt_opts *dst, *src = src_fc->security;
+
+	if (!src)
+		return 0;
+
+	fc->security = kzalloc(sizeof(struct smack_mnt_opts), GFP_KERNEL);
+	if (!fc->security)
+		return -ENOMEM;
+	dst = fc->security;
+
+	if (src->fsdefault) {
+		dst->fsdefault = kstrdup(src->fsdefault, GFP_KERNEL);
+		if (!dst->fsdefault)
+			return -ENOMEM;
+	}
+	if (src->fsfloor) {
+		dst->fsfloor = kstrdup(src->fsfloor, GFP_KERNEL);
+		if (!dst->fsfloor)
+			return -ENOMEM;
+	}
+	if (src->fshat) {
+		dst->fshat = kstrdup(src->fshat, GFP_KERNEL);
+		if (!dst->fshat)
+			return -ENOMEM;
+	}
+	if (src->fsroot) {
+		dst->fsroot = kstrdup(src->fsroot, GFP_KERNEL);
+		if (!dst->fsroot)
+			return -ENOMEM;
+	}
+	if (src->fstransmute) {
+		dst->fstransmute = kstrdup(src->fstransmute, GFP_KERNEL);
+		if (!dst->fstransmute)
+			return -ENOMEM;
+	}
+	return 0;
+}
+
+static const struct fs_parameter_spec smack_param_specs[] = {
+	fsparam_string("fsdefault",	Opt_fsdefault),
+	fsparam_string("fsfloor",	Opt_fsfloor),
+	fsparam_string("fshat",		Opt_fshat),
+	fsparam_string("fsroot",	Opt_fsroot),
+	fsparam_string("fstransmute",	Opt_fstransmute),
+	{}
+};
+
+static const struct fs_parameter_description smack_fs_parameters = {
+	.name		= "smack",
+	.specs		= smack_param_specs,
+};
+
+/**
+ * smack_fs_context_parse_param - Parse a single mount parameter
+ * @fc: The new filesystem context being constructed.
+ * @param: The parameter.
+ *
+ * Returns 0 on success, -ENOPARAM to pass the parameter on or anything else on
+ * error.
+ */
+static int smack_fs_context_parse_param(struct fs_context *fc,
+					struct fs_parameter *param)
+{
+	struct fs_parse_result result;
+	int opt, rc;
+
+	opt = fs_parse(fc, &smack_fs_parameters, param, &result);
+	if (opt < 0)
+		return opt;
+
+	rc = smack_add_opt(opt, param->string, &fc->security);
+	if (!rc)
+		param->string = NULL;
+	return rc;
+}
+
 static int smack_sb_eat_lsm_opts(char *options, void **mnt_opts)
 {
 	char *from = options, *to = options;
@@ -4495,6 +4582,9 @@ static struct security_hook_list smack_hooks[] __lsm_ro_after_init = {
 	LSM_HOOK_INIT(ptrace_traceme, smack_ptrace_traceme),
 	LSM_HOOK_INIT(syslog, smack_syslog),
 
+	LSM_HOOK_INIT(fs_context_dup, smack_fs_context_dup),
+	LSM_HOOK_INIT(fs_context_parse_param, smack_fs_context_parse_param),
+
 	LSM_HOOK_INIT(sb_alloc_security, smack_sb_alloc_security),
 	LSM_HOOK_INIT(sb_free_security, smack_sb_free_security),
 	LSM_HOOK_INIT(sb_free_mnt_opts, smack_free_mnt_opts),