1 files changed, 134 insertions, 91 deletions

diff --git a/security/apparmor/apparmorfs.c b/security/apparmor/apparmorfs.c
index 2f84bd23edb6..242c71b3fb6e 100644
--- a/security/apparmor/apparmorfs.c
+++ b/security/apparmor/apparmorfs.c
@@ -32,6 +32,7 @@
 #include "include/crypto.h"
 #include "include/ipc.h"
 #include "include/label.h"
+#include "include/lib.h"
 #include "include/policy.h"
 #include "include/policy_ns.h"
 #include "include/resource.h"
@@ -62,6 +63,7 @@
  * securityfs and apparmorfs filesystems.
  */
 
+#define IREF_POISON 101
 
 /*
  * support fns
@@ -79,7 +81,7 @@ static void rawdata_f_data_free(struct rawdata_f_data *private)
 	if (!private)
 		return;
 
-	aa_put_loaddata(private->loaddata);
+	aa_put_i_loaddata(private->loaddata);
 	kvfree(private);
 }
 
@@ -153,6 +155,71 @@ static int aafs_show_path(struct seq_file *seq, struct dentry *dentry)
 	return 0;
 }
 
+static struct aa_ns *get_ns_common_ref(struct aa_common_ref *ref)
+{
+	if (ref) {
+		struct aa_label *reflabel = container_of(ref, struct aa_label,
+							 count);
+		return aa_get_ns(labels_ns(reflabel));
+	}
+
+	return NULL;
+}
+
+static struct aa_proxy *get_proxy_common_ref(struct aa_common_ref *ref)
+{
+	if (ref)
+		return aa_get_proxy(container_of(ref, struct aa_proxy, count));
+
+	return NULL;
+}
+
+static struct aa_loaddata *get_loaddata_common_ref(struct aa_common_ref *ref)
+{
+	if (ref)
+		return aa_get_i_loaddata(container_of(ref, struct aa_loaddata,
+						      count));
+	return NULL;
+}
+
+static void aa_put_common_ref(struct aa_common_ref *ref)
+{
+	if (!ref)
+		return;
+
+	switch (ref->reftype) {
+	case REF_RAWDATA:
+		aa_put_i_loaddata(container_of(ref, struct aa_loaddata,
+					       count));
+		break;
+	case REF_PROXY:
+		aa_put_proxy(container_of(ref, struct aa_proxy,
+					  count));
+		break;
+	case REF_NS:
+		/* ns count is held on its unconfined label */
+		aa_put_ns(labels_ns(container_of(ref, struct aa_label, count)));
+		break;
+	default:
+		AA_BUG(true, "unknown refcount type");
+		break;
+	}
+}
+
+static void aa_get_common_ref(struct aa_common_ref *ref)
+{
+	kref_get(&ref->count);
+}
+
+static void aafs_evict(struct inode *inode)
+{
+	struct aa_common_ref *ref = inode->i_private;
+
+	clear_inode(inode);
+	aa_put_common_ref(ref);
+	inode->i_private = (void *) IREF_POISON;
+}
+
 static void aafs_free_inode(struct inode *inode)
 {
 	if (S_ISLNK(inode->i_mode))
@@ -162,6 +229,7 @@ static void aafs_free_inode(struct inode *inode)
 
 static const struct super_operations aafs_super_ops = {
 	.statfs = simple_statfs,
+	.evict_inode = aafs_evict,
 	.free_inode = aafs_free_inode,
 	.show_path = aafs_show_path,
 };
@@ -262,7 +330,8 @@ static int __aafs_setup_d_inode(struct inode *dir, struct dentry *dentry,
  * aafs_remove(). Will return ERR_PTR on failure.
  */
 static struct dentry *aafs_create(const char *name, umode_t mode,
-				  struct dentry *parent, void *data, void *link,
+				  struct dentry *parent,
+				  struct aa_common_ref *data, void *link,
 				  const struct file_operations *fops,
 				  const struct inode_operations *iops)
 {
@@ -299,6 +368,9 @@ static struct dentry *aafs_create(const char *name, umode_t mode,
 		goto fail_dentry;
 	inode_unlock(dir);
 
+	if (data)
+		aa_get_common_ref(data);
+
 	return dentry;
 
 fail_dentry:
@@ -323,7 +395,8 @@ fail_lock:
  * see aafs_create
  */
 static struct dentry *aafs_create_file(const char *name, umode_t mode,
-				       struct dentry *parent, void *data,
+				       struct dentry *parent,
+				       struct aa_common_ref *data,
 				       const struct file_operations *fops)
 {
 	return aafs_create(name, mode, parent, data, NULL, fops, NULL);
@@ -409,7 +482,8 @@ static struct aa_loaddata *aa_simple_write_to_buffer(const char __user *userbuf,
 
 	data->size = copy_size;
 	if (copy_from_user(data->data, userbuf, copy_size)) {
-		aa_put_loaddata(data);
+		/* trigger free - don't need to put pcount */
+		aa_put_i_loaddata(data);
 		return ERR_PTR(-EFAULT);
 	}
 
@@ -417,7 +491,8 @@ static struct aa_loaddata *aa_simple_write_to_buffer(const char __user *userbuf,
 }
 
 static ssize_t policy_update(u32 mask, const char __user *buf, size_t size,
-			     loff_t *pos, struct aa_ns *ns)
+			     loff_t *pos, struct aa_ns *ns,
+			     const struct cred *ocred)
 {
 	struct aa_loaddata *data;
 	struct aa_label *label;
@@ -428,7 +503,7 @@ static ssize_t policy_update(u32 mask, const char __user *buf, size_t size,
 	/* high level check about policy management - fine grained in
 	 * below after unpack
 	 */
-	error = aa_may_manage_policy(current_cred(), label, ns, mask);
+	error = aa_may_manage_policy(current_cred(), label, ns, ocred, mask);
 	if (error)
 		goto end_section;
 
@@ -436,7 +511,10 @@ static ssize_t policy_update(u32 mask, const char __user *buf, size_t size,
 	error = PTR_ERR(data);
 	if (!IS_ERR(data)) {
 		error = aa_replace_profiles(ns, label, mask, data);
-		aa_put_loaddata(data);
+		/* put pcount, which will put count and free if no
+		 * profiles referencing it.
+		 */
+		aa_put_profile_loaddata(data);
 	}
 end_section:
 	end_current_label_crit_section(label);
@@ -448,8 +526,9 @@ end_section:
 static ssize_t profile_load(struct file *f, const char __user *buf, size_t size,
 			    loff_t *pos)
 {
-	struct aa_ns *ns = aa_get_ns(f->f_inode->i_private);
-	int error = policy_update(AA_MAY_LOAD_POLICY, buf, size, pos, ns);
+	struct aa_ns *ns = get_ns_common_ref(f->f_inode->i_private);
+	int error = policy_update(AA_MAY_LOAD_POLICY, buf, size, pos, ns,
+				  f->f_cred);
 
 	aa_put_ns(ns);
 
@@ -465,9 +544,9 @@ static const struct file_operations aa_fs_profile_load = {
 static ssize_t profile_replace(struct file *f, const char __user *buf,
 			       size_t size, loff_t *pos)
 {
-	struct aa_ns *ns = aa_get_ns(f->f_inode->i_private);
+	struct aa_ns *ns = get_ns_common_ref(f->f_inode->i_private);
 	int error = policy_update(AA_MAY_LOAD_POLICY | AA_MAY_REPLACE_POLICY,
-				  buf, size, pos, ns);
+				  buf, size, pos, ns, f->f_cred);
 	aa_put_ns(ns);
 
 	return error;
@@ -485,14 +564,14 @@ static ssize_t profile_remove(struct file *f, const char __user *buf,
 	struct aa_loaddata *data;
 	struct aa_label *label;
 	ssize_t error;
-	struct aa_ns *ns = aa_get_ns(f->f_inode->i_private);
+	struct aa_ns *ns = get_ns_common_ref(f->f_inode->i_private);
 
 	label = begin_current_label_crit_section();
 	/* high level check about policy management - fine grained in
 	 * below after unpack
 	 */
 	error = aa_may_manage_policy(current_cred(), label, ns,
-				     AA_MAY_REMOVE_POLICY);
+				     f->f_cred, AA_MAY_REMOVE_POLICY);
 	if (error)
 		goto out;
 
@@ -506,7 +585,7 @@ static ssize_t profile_remove(struct file *f, const char __user *buf,
 	if (!IS_ERR(data)) {
 		data->data[size] = 0;
 		error = aa_remove_profiles(ns, label, data->data, size);
-		aa_put_loaddata(data);
+		aa_put_profile_loaddata(data);
 	}
  out:
 	end_current_label_crit_section(label);
@@ -575,7 +654,7 @@ static int ns_revision_open(struct inode *inode, struct file *file)
 	if (!rev)
 		return -ENOMEM;
 
-	rev->ns = aa_get_ns(inode->i_private);
+	rev->ns = get_ns_common_ref(inode->i_private);
 	if (!rev->ns)
 		rev->ns = aa_get_current_ns();
 	file->private_data = rev;
@@ -1061,7 +1140,7 @@ static const struct file_operations seq_profile_ ##NAME ##_fops = {	      \
 static int seq_profile_open(struct inode *inode, struct file *file,
 			    int (*show)(struct seq_file *, void *))
 {
-	struct aa_proxy *proxy = aa_get_proxy(inode->i_private);
+	struct aa_proxy *proxy = get_proxy_common_ref(inode->i_private);
 	int error = single_open(file, show, proxy);
 
 	if (error) {
@@ -1253,18 +1332,17 @@ static const struct file_operations seq_rawdata_ ##NAME ##_fops = {	      \
 static int seq_rawdata_open(struct inode *inode, struct file *file,
 			    int (*show)(struct seq_file *, void *))
 {
-	struct aa_loaddata *data = __aa_get_loaddata(inode->i_private);
+	struct aa_loaddata *data = get_loaddata_common_ref(inode->i_private);
 	int error;
 
 	if (!data)
-		/* lost race this ent is being reaped */
 		return -ENOENT;
 
 	error = single_open(file, show, data);
 	if (error) {
 		AA_BUG(file->private_data &&
 		       ((struct seq_file *)file->private_data)->private);
-		aa_put_loaddata(data);
+		aa_put_i_loaddata(data);
 	}
 
 	return error;
@@ -1275,7 +1353,7 @@ static int seq_rawdata_release(struct inode *inode, struct file *file)
 	struct seq_file *seq = (struct seq_file *) file->private_data;
 
 	if (seq)
-		aa_put_loaddata(seq->private);
+		aa_put_i_loaddata(seq->private);
 
 	return single_release(inode, file);
 }
@@ -1387,9 +1465,8 @@ static int rawdata_open(struct inode *inode, struct file *file)
 	if (!aa_current_policy_view_capable(NULL))
 		return -EACCES;
 
-	loaddata = __aa_get_loaddata(inode->i_private);
+	loaddata = get_loaddata_common_ref(inode->i_private);
 	if (!loaddata)
-		/* lost race: this entry is being reaped */
 		return -ENOENT;
 
 	private = rawdata_f_data_alloc(loaddata->size);
@@ -1414,7 +1491,7 @@ fail_decompress:
 	return error;
 
 fail_private_alloc:
-	aa_put_loaddata(loaddata);
+	aa_put_i_loaddata(loaddata);
 	return error;
 }
 
@@ -1431,7 +1508,6 @@ static void remove_rawdata_dents(struct aa_loaddata *rawdata)
 
 	for (i = 0; i < AAFS_LOADDATA_NDENTS; i++) {
 		if (!IS_ERR_OR_NULL(rawdata->dents[i])) {
-			/* no refcounts on i_private */
 			aafs_remove(rawdata->dents[i]);
 			rawdata->dents[i] = NULL;
 		}
@@ -1474,35 +1550,37 @@ int __aa_fs_create_rawdata(struct aa_ns *ns, struct aa_loaddata *rawdata)
 		return PTR_ERR(dir);
 	rawdata->dents[AAFS_LOADDATA_DIR] = dir;
 
-	dent = aafs_create_file("abi", S_IFREG | 0444, dir, rawdata,
+	dent = aafs_create_file("abi", S_IFREG | 0444, dir, &rawdata->count,
 				      &seq_rawdata_abi_fops);
 	if (IS_ERR(dent))
 		goto fail;
 	rawdata->dents[AAFS_LOADDATA_ABI] = dent;
 
-	dent = aafs_create_file("revision", S_IFREG | 0444, dir, rawdata,
-				      &seq_rawdata_revision_fops);
+	dent = aafs_create_file("revision", S_IFREG | 0444, dir,
+				&rawdata->count,
+				&seq_rawdata_revision_fops);
 	if (IS_ERR(dent))
 		goto fail;
 	rawdata->dents[AAFS_LOADDATA_REVISION] = dent;
 
 	if (aa_g_hash_policy) {
 		dent = aafs_create_file("sha256", S_IFREG | 0444, dir,
-					      rawdata, &seq_rawdata_hash_fops);
+					&rawdata->count,
+					&seq_rawdata_hash_fops);
 		if (IS_ERR(dent))
 			goto fail;
 		rawdata->dents[AAFS_LOADDATA_HASH] = dent;
 	}
 
 	dent = aafs_create_file("compressed_size", S_IFREG | 0444, dir,
-				rawdata,
+				&rawdata->count,
 				&seq_rawdata_compressed_size_fops);
 	if (IS_ERR(dent))
 		goto fail;
 	rawdata->dents[AAFS_LOADDATA_COMPRESSED_SIZE] = dent;
 
-	dent = aafs_create_file("raw_data", S_IFREG | 0444,
-				      dir, rawdata, &rawdata_fops);
+	dent = aafs_create_file("raw_data", S_IFREG | 0444, dir,
+				&rawdata->count, &rawdata_fops);
 	if (IS_ERR(dent))
 		goto fail;
 	rawdata->dents[AAFS_LOADDATA_DATA] = dent;
@@ -1510,13 +1588,11 @@ int __aa_fs_create_rawdata(struct aa_ns *ns, struct aa_loaddata *rawdata)
 
 	rawdata->ns = aa_get_ns(ns);
 	list_add(&rawdata->list, &ns->rawdata_list);
-	/* no refcount on inode rawdata */
 
 	return 0;
 
 fail:
 	remove_rawdata_dents(rawdata);
-
 	return PTR_ERR(dent);
 }
 #endif /* CONFIG_SECURITY_APPARMOR_EXPORT_BINARY */
@@ -1540,13 +1616,10 @@ void __aafs_profile_rmdir(struct aa_profile *profile)
 		__aafs_profile_rmdir(child);
 
 	for (i = AAFS_PROF_SIZEOF - 1; i >= 0; --i) {
-		struct aa_proxy *proxy;
 		if (!profile->dents[i])
 			continue;
 
-		proxy = d_inode(profile->dents[i])->i_private;
 		aafs_remove(profile->dents[i]);
-		aa_put_proxy(proxy);
 		profile->dents[i] = NULL;
 	}
 }
@@ -1580,14 +1653,7 @@ static struct dentry *create_profile_file(struct dentry *dir, const char *name,
 					  struct aa_profile *profile,
 					  const struct file_operations *fops)
 {
-	struct aa_proxy *proxy = aa_get_proxy(profile->label.proxy);
-	struct dentry *dent;
-
-	dent = aafs_create_file(name, S_IFREG | 0444, dir, proxy, fops);
-	if (IS_ERR(dent))
-		aa_put_proxy(proxy);
-
-	return dent;
+	return aafs_create_file(name, S_IFREG | 0444, dir, &profile->label.proxy->count, fops);
 }
 
 #ifdef CONFIG_SECURITY_APPARMOR_EXPORT_BINARY
@@ -1637,7 +1703,8 @@ static const char *rawdata_get_link_base(struct dentry *dentry,
 					 struct delayed_call *done,
 					 const char *name)
 {
-	struct aa_proxy *proxy = inode->i_private;
+	struct aa_common_ref *ref = inode->i_private;
+	struct aa_proxy *proxy = container_of(ref, struct aa_proxy, count);
 	struct aa_label *label;
 	struct aa_profile *profile;
 	char *target;
@@ -1779,27 +1846,24 @@ int __aafs_profile_mkdir(struct aa_profile *profile, struct dentry *parent)
 	if (profile->rawdata) {
 		if (aa_g_hash_policy) {
 			dent = aafs_create("raw_sha256", S_IFLNK | 0444, dir,
-					   profile->label.proxy, NULL, NULL,
-					   &rawdata_link_sha256_iops);
+					   &profile->label.proxy->count, NULL,
+					   NULL, &rawdata_link_sha256_iops);
 			if (IS_ERR(dent))
 				goto fail;
-			aa_get_proxy(profile->label.proxy);
 			profile->dents[AAFS_PROF_RAW_HASH] = dent;
 		}
 		dent = aafs_create("raw_abi", S_IFLNK | 0444, dir,
-				   profile->label.proxy, NULL, NULL,
+				   &profile->label.proxy->count, NULL, NULL,
 				   &rawdata_link_abi_iops);
 		if (IS_ERR(dent))
 			goto fail;
-		aa_get_proxy(profile->label.proxy);
 		profile->dents[AAFS_PROF_RAW_ABI] = dent;
 
 		dent = aafs_create("raw_data", S_IFLNK | 0444, dir,
-				   profile->label.proxy, NULL, NULL,
+				   &profile->label.proxy->count, NULL, NULL,
 				   &rawdata_link_data_iops);
 		if (IS_ERR(dent))
 			goto fail;
-		aa_get_proxy(profile->label.proxy);
 		profile->dents[AAFS_PROF_RAW_DATA] = dent;
 	}
 #endif /*CONFIG_SECURITY_APPARMOR_EXPORT_BINARY */
@@ -1830,13 +1894,13 @@ static struct dentry *ns_mkdir_op(struct mnt_idmap *idmap, struct inode *dir,
 	int error;
 
 	label = begin_current_label_crit_section();
-	error = aa_may_manage_policy(current_cred(), label, NULL,
+	error = aa_may_manage_policy(current_cred(), label, NULL, NULL,
 				     AA_MAY_LOAD_POLICY);
 	end_current_label_crit_section(label);
 	if (error)
 		return ERR_PTR(error);
 
-	parent = aa_get_ns(dir->i_private);
+	parent = get_ns_common_ref(dir->i_private);
 	AA_BUG(d_inode(ns_subns_dir(parent)) != dir);
 
 	/* we have to unlock and then relock to get locking order right
@@ -1880,13 +1944,13 @@ static int ns_rmdir_op(struct inode *dir, struct dentry *dentry)
 	int error;
 
 	label = begin_current_label_crit_section();
-	error = aa_may_manage_policy(current_cred(), label, NULL,
+	error = aa_may_manage_policy(current_cred(), label, NULL, NULL,
 				     AA_MAY_LOAD_POLICY);
 	end_current_label_crit_section(label);
 	if (error)
 		return error;
 
-	parent = aa_get_ns(dir->i_private);
+	parent = get_ns_common_ref(dir->i_private);
 	/* rmdir calls the generic securityfs functions to remove files
 	 * from the apparmor dir. It is up to the apparmor ns locking
 	 * to avoid races.
@@ -1956,27 +2020,6 @@ void __aafs_ns_rmdir(struct aa_ns *ns)
 
 	__aa_fs_list_remove_rawdata(ns);
 
-	if (ns_subns_dir(ns)) {
-		sub = d_inode(ns_subns_dir(ns))->i_private;
-		aa_put_ns(sub);
-	}
-	if (ns_subload(ns)) {
-		sub = d_inode(ns_subload(ns))->i_private;
-		aa_put_ns(sub);
-	}
-	if (ns_subreplace(ns)) {
-		sub = d_inode(ns_subreplace(ns))->i_private;
-		aa_put_ns(sub);
-	}
-	if (ns_subremove(ns)) {
-		sub = d_inode(ns_subremove(ns))->i_private;
-		aa_put_ns(sub);
-	}
-	if (ns_subrevision(ns)) {
-		sub = d_inode(ns_subrevision(ns))->i_private;
-		aa_put_ns(sub);
-	}
-
 	for (i = AAFS_NS_SIZEOF - 1; i >= 0; --i) {
 		aafs_remove(ns->dents[i]);
 		ns->dents[i] = NULL;
@@ -2001,40 +2044,40 @@ static int __aafs_ns_mkdir_entries(struct aa_ns *ns, struct dentry *dir)
 		return PTR_ERR(dent);
 	ns_subdata_dir(ns) = dent;
 
-	dent = aafs_create_file("revision", 0444, dir, ns,
+	dent = aafs_create_file("revision", 0444, dir,
+				&ns->unconfined->label.count,
 				&aa_fs_ns_revision_fops);
 	if (IS_ERR(dent))
 		return PTR_ERR(dent);
-	aa_get_ns(ns);
 	ns_subrevision(ns) = dent;
 
-	dent = aafs_create_file(".load", 0640, dir, ns,
-				      &aa_fs_profile_load);
+	dent = aafs_create_file(".load", 0640, dir,
+				&ns->unconfined->label.count,
+				&aa_fs_profile_load);
 	if (IS_ERR(dent))
 		return PTR_ERR(dent);
-	aa_get_ns(ns);
 	ns_subload(ns) = dent;
 
-	dent = aafs_create_file(".replace", 0640, dir, ns,
-				      &aa_fs_profile_replace);
+	dent = aafs_create_file(".replace", 0640, dir,
+				&ns->unconfined->label.count,
+				&aa_fs_profile_replace);
 	if (IS_ERR(dent))
 		return PTR_ERR(dent);
-	aa_get_ns(ns);
 	ns_subreplace(ns) = dent;
 
-	dent = aafs_create_file(".remove", 0640, dir, ns,
-				      &aa_fs_profile_remove);
+	dent = aafs_create_file(".remove", 0640, dir,
+				&ns->unconfined->label.count,
+				&aa_fs_profile_remove);
 	if (IS_ERR(dent))
 		return PTR_ERR(dent);
-	aa_get_ns(ns);
 	ns_subremove(ns) = dent;
 
 	  /* use create_dentry so we can supply private data */
-	dent = aafs_create("namespaces", S_IFDIR | 0755, dir, ns, NULL, NULL,
-			   &ns_dir_inode_operations);
+	dent = aafs_create("namespaces", S_IFDIR | 0755, dir,
+			   &ns->unconfined->label.count,
+			   NULL, NULL, &ns_dir_inode_operations);
 	if (IS_ERR(dent))
 		return PTR_ERR(dent);
-	aa_get_ns(ns);
 	ns_subns_dir(ns) = dent;
 
 	return 0;