diff options
Diffstat (limited to 'security/selinux/selinuxfs.c')
-rw-r--r-- | security/selinux/selinuxfs.c | 259 |
1 files changed, 174 insertions, 85 deletions
diff --git a/security/selinux/selinuxfs.c b/security/selinux/selinuxfs.c index 4781314c2510..4bde570d56a2 100644 --- a/security/selinux/selinuxfs.c +++ b/security/selinux/selinuxfs.c @@ -20,6 +20,7 @@ #include <linux/fs_context.h> #include <linux/mount.h> #include <linux/mutex.h> +#include <linux/namei.h> #include <linux/init.h> #include <linux/string.h> #include <linux/security.h> @@ -74,7 +75,6 @@ struct selinux_fs_info { unsigned long last_class_ino; bool policy_opened; struct dentry *policycap_dir; - struct mutex mutex; unsigned long last_ino; struct selinux_state *state; struct super_block *sb; @@ -88,7 +88,6 @@ static int selinux_fs_info_create(struct super_block *sb) if (!fsi) return -ENOMEM; - mutex_init(&fsi->mutex); fsi->last_ino = SEL_INO_NEXT - 1; fsi->state = &selinux_state; fsi->sb = sb; @@ -117,6 +116,10 @@ static void selinux_fs_info_free(struct super_block *sb) #define SEL_POLICYCAP_INO_OFFSET 0x08000000 #define SEL_INO_MASK 0x00ffffff +#define BOOL_DIR_NAME "booleans" +#define CLASS_DIR_NAME "class" +#define POLICYCAP_DIR_NAME "policy_capabilities" + #define TMPBUFLEN 12 static ssize_t sel_read_enforce(struct file *filp, char __user *buf, size_t count, loff_t *ppos) @@ -346,14 +349,24 @@ static const struct file_operations sel_policyvers_ops = { }; /* declaration for sel_write_load */ -static int sel_make_bools(struct selinux_fs_info *fsi); -static int sel_make_classes(struct selinux_fs_info *fsi); -static int sel_make_policycap(struct selinux_fs_info *fsi); +static int sel_make_bools(struct selinux_policy *newpolicy, struct dentry *bool_dir, + unsigned int *bool_num, char ***bool_pending_names, + unsigned int **bool_pending_values); +static int sel_make_classes(struct selinux_policy *newpolicy, + struct dentry *class_dir, + unsigned long *last_class_ino); /* declaration for sel_make_class_dirs */ static struct dentry *sel_make_dir(struct dentry *dir, const char *name, unsigned long *ino); +/* declaration for sel_make_policy_nodes */ +static struct dentry *sel_make_disconnected_dir(struct super_block *sb, + unsigned long *ino); + +/* declaration for sel_make_policy_nodes */ +static void sel_remove_entries(struct dentry *de); + static ssize_t sel_read_mls(struct file *filp, char __user *buf, size_t count, loff_t *ppos) { @@ -385,7 +398,7 @@ static int sel_open_policy(struct inode *inode, struct file *filp) BUG_ON(filp->private_data); - mutex_lock(&fsi->mutex); + mutex_lock(&fsi->state->policy_mutex); rc = avc_has_perm(&selinux_state, current_sid(), SECINITSID_SECURITY, @@ -402,25 +415,25 @@ static int sel_open_policy(struct inode *inode, struct file *filp) if (!plm) goto err; - if (i_size_read(inode) != security_policydb_len(state)) { - inode_lock(inode); - i_size_write(inode, security_policydb_len(state)); - inode_unlock(inode); - } - rc = security_read_policy(state, &plm->data, &plm->len); if (rc) goto err; + if ((size_t)i_size_read(inode) != plm->len) { + inode_lock(inode); + i_size_write(inode, plm->len); + inode_unlock(inode); + } + fsi->policy_opened = 1; filp->private_data = plm; - mutex_unlock(&fsi->mutex); + mutex_unlock(&fsi->state->policy_mutex); return 0; err: - mutex_unlock(&fsi->mutex); + mutex_unlock(&fsi->state->policy_mutex); if (plm) vfree(plm->data); @@ -508,29 +521,94 @@ static const struct file_operations sel_policy_ops = { .llseek = generic_file_llseek, }; -static int sel_make_policy_nodes(struct selinux_fs_info *fsi) +static void sel_remove_old_bool_data(unsigned int bool_num, char **bool_names, + unsigned int *bool_values) { - int ret; + u32 i; + + /* bool_dir cleanup */ + for (i = 0; i < bool_num; i++) + kfree(bool_names[i]); + kfree(bool_names); + kfree(bool_values); +} - ret = sel_make_bools(fsi); +static int sel_make_policy_nodes(struct selinux_fs_info *fsi, + struct selinux_policy *newpolicy) +{ + int ret = 0; + struct dentry *tmp_parent, *tmp_bool_dir, *tmp_class_dir, *old_dentry; + unsigned int tmp_bool_num, old_bool_num; + char **tmp_bool_names, **old_bool_names; + unsigned int *tmp_bool_values, *old_bool_values; + unsigned long tmp_ino = fsi->last_ino; /* Don't increment last_ino in this function */ + + tmp_parent = sel_make_disconnected_dir(fsi->sb, &tmp_ino); + if (IS_ERR(tmp_parent)) + return PTR_ERR(tmp_parent); + + tmp_ino = fsi->bool_dir->d_inode->i_ino - 1; /* sel_make_dir will increment and set */ + tmp_bool_dir = sel_make_dir(tmp_parent, BOOL_DIR_NAME, &tmp_ino); + if (IS_ERR(tmp_bool_dir)) { + ret = PTR_ERR(tmp_bool_dir); + goto out; + } + + tmp_ino = fsi->class_dir->d_inode->i_ino - 1; /* sel_make_dir will increment and set */ + tmp_class_dir = sel_make_dir(tmp_parent, CLASS_DIR_NAME, &tmp_ino); + if (IS_ERR(tmp_class_dir)) { + ret = PTR_ERR(tmp_class_dir); + goto out; + } + + ret = sel_make_bools(newpolicy, tmp_bool_dir, &tmp_bool_num, + &tmp_bool_names, &tmp_bool_values); if (ret) { pr_err("SELinux: failed to load policy booleans\n"); - return ret; + goto out; } - ret = sel_make_classes(fsi); + ret = sel_make_classes(newpolicy, tmp_class_dir, + &fsi->last_class_ino); if (ret) { pr_err("SELinux: failed to load policy classes\n"); - return ret; + goto out; } - ret = sel_make_policycap(fsi); - if (ret) { - pr_err("SELinux: failed to load policy capabilities\n"); - return ret; - } + /* booleans */ + old_dentry = fsi->bool_dir; + lock_rename(tmp_bool_dir, old_dentry); + d_exchange(tmp_bool_dir, fsi->bool_dir); - return 0; + old_bool_num = fsi->bool_num; + old_bool_names = fsi->bool_pending_names; + old_bool_values = fsi->bool_pending_values; + + fsi->bool_num = tmp_bool_num; + fsi->bool_pending_names = tmp_bool_names; + fsi->bool_pending_values = tmp_bool_values; + + sel_remove_old_bool_data(old_bool_num, old_bool_names, old_bool_values); + + fsi->bool_dir = tmp_bool_dir; + unlock_rename(tmp_bool_dir, old_dentry); + + /* classes */ + old_dentry = fsi->class_dir; + lock_rename(tmp_class_dir, old_dentry); + d_exchange(tmp_class_dir, fsi->class_dir); + fsi->class_dir = tmp_class_dir; + unlock_rename(tmp_class_dir, old_dentry); + +out: + /* Since the other temporary dirs are children of tmp_parent + * this will handle all the cleanup in the case of a failure before + * the swapover + */ + sel_remove_entries(tmp_parent); + dput(tmp_parent); /* d_genocide() only handles the children */ + + return ret; } static ssize_t sel_write_load(struct file *file, const char __user *buf, @@ -538,10 +616,11 @@ static ssize_t sel_write_load(struct file *file, const char __user *buf, { struct selinux_fs_info *fsi = file_inode(file)->i_sb->s_fs_info; + struct selinux_policy *newpolicy; ssize_t length; void *data = NULL; - mutex_lock(&fsi->mutex); + mutex_lock(&fsi->state->policy_mutex); length = avc_has_perm(&selinux_state, current_sid(), SECINITSID_SECURITY, @@ -563,15 +642,19 @@ static ssize_t sel_write_load(struct file *file, const char __user *buf, if (copy_from_user(data, buf, count) != 0) goto out; - length = security_load_policy(fsi->state, data, count); + length = security_load_policy(fsi->state, data, count, &newpolicy); if (length) { pr_warn_ratelimited("SELinux: failed to load policy\n"); goto out; } - length = sel_make_policy_nodes(fsi); - if (length) + length = sel_make_policy_nodes(fsi, newpolicy); + if (length) { + selinux_policy_cancel(fsi->state, newpolicy); goto out1; + } + + selinux_policy_commit(fsi->state, newpolicy); length = count; @@ -581,7 +664,7 @@ out1: from_kuid(&init_user_ns, audit_get_loginuid(current)), audit_get_sessionid(current)); out: - mutex_unlock(&fsi->mutex); + mutex_unlock(&fsi->state->policy_mutex); vfree(data); return length; } @@ -634,7 +717,8 @@ static ssize_t sel_read_checkreqprot(struct file *filp, char __user *buf, char tmpbuf[TMPBUFLEN]; ssize_t length; - length = scnprintf(tmpbuf, TMPBUFLEN, "%u", fsi->state->checkreqprot); + length = scnprintf(tmpbuf, TMPBUFLEN, "%u", + checkreqprot_get(fsi->state)); return simple_read_from_buffer(buf, count, ppos, tmpbuf, length); } @@ -676,7 +760,7 @@ static ssize_t sel_write_checkreqprot(struct file *file, const char __user *buf, comm, current->pid); } - fsi->state->checkreqprot = new_value ? 1 : 0; + checkreqprot_set(fsi->state, (new_value ? 1 : 0)); length = count; out: kfree(page); @@ -1186,7 +1270,7 @@ static ssize_t sel_read_bool(struct file *filep, char __user *buf, unsigned index = file_inode(filep)->i_ino & SEL_INO_MASK; const char *name = filep->f_path.dentry->d_name.name; - mutex_lock(&fsi->mutex); + mutex_lock(&fsi->state->policy_mutex); ret = -EINVAL; if (index >= fsi->bool_num || strcmp(name, @@ -1205,14 +1289,14 @@ static ssize_t sel_read_bool(struct file *filep, char __user *buf, } length = scnprintf(page, PAGE_SIZE, "%d %d", cur_enforcing, fsi->bool_pending_values[index]); - mutex_unlock(&fsi->mutex); + mutex_unlock(&fsi->state->policy_mutex); ret = simple_read_from_buffer(buf, count, ppos, page, length); out_free: free_page((unsigned long)page); return ret; out_unlock: - mutex_unlock(&fsi->mutex); + mutex_unlock(&fsi->state->policy_mutex); goto out_free; } @@ -1237,7 +1321,7 @@ static ssize_t sel_write_bool(struct file *filep, const char __user *buf, if (IS_ERR(page)) return PTR_ERR(page); - mutex_lock(&fsi->mutex); + mutex_lock(&fsi->state->policy_mutex); length = avc_has_perm(&selinux_state, current_sid(), SECINITSID_SECURITY, @@ -1262,7 +1346,7 @@ static ssize_t sel_write_bool(struct file *filep, const char __user *buf, length = count; out: - mutex_unlock(&fsi->mutex); + mutex_unlock(&fsi->state->policy_mutex); kfree(page); return length; } @@ -1293,7 +1377,7 @@ static ssize_t sel_commit_bools_write(struct file *filep, if (IS_ERR(page)) return PTR_ERR(page); - mutex_lock(&fsi->mutex); + mutex_lock(&fsi->state->policy_mutex); length = avc_has_perm(&selinux_state, current_sid(), SECINITSID_SECURITY, @@ -1315,7 +1399,7 @@ static ssize_t sel_commit_bools_write(struct file *filep, length = count; out: - mutex_unlock(&fsi->mutex); + mutex_unlock(&fsi->state->policy_mutex); kfree(page); return length; } @@ -1331,14 +1415,13 @@ static void sel_remove_entries(struct dentry *de) shrink_dcache_parent(de); } -#define BOOL_DIR_NAME "booleans" - -static int sel_make_bools(struct selinux_fs_info *fsi) +static int sel_make_bools(struct selinux_policy *newpolicy, struct dentry *bool_dir, + unsigned int *bool_num, char ***bool_pending_names, + unsigned int **bool_pending_values) { int ret; ssize_t len; struct dentry *dentry = NULL; - struct dentry *dir = fsi->bool_dir; struct inode *inode = NULL; struct inode_security_struct *isec; char **names = NULL, *page; @@ -1346,34 +1429,23 @@ static int sel_make_bools(struct selinux_fs_info *fsi) int *values = NULL; u32 sid; - /* remove any existing files */ - for (i = 0; i < fsi->bool_num; i++) - kfree(fsi->bool_pending_names[i]); - kfree(fsi->bool_pending_names); - kfree(fsi->bool_pending_values); - fsi->bool_num = 0; - fsi->bool_pending_names = NULL; - fsi->bool_pending_values = NULL; - - sel_remove_entries(dir); - ret = -ENOMEM; page = (char *)get_zeroed_page(GFP_KERNEL); if (!page) goto out; - ret = security_get_bools(fsi->state, &num, &names, &values); + ret = security_get_bools(newpolicy, &num, &names, &values); if (ret) goto out; for (i = 0; i < num; i++) { ret = -ENOMEM; - dentry = d_alloc_name(dir, names[i]); + dentry = d_alloc_name(bool_dir, names[i]); if (!dentry) goto out; ret = -ENOMEM; - inode = sel_make_inode(dir->d_sb, S_IFREG | S_IRUGO | S_IWUSR); + inode = sel_make_inode(bool_dir->d_sb, S_IFREG | S_IRUGO | S_IWUSR); if (!inode) { dput(dentry); goto out; @@ -1388,7 +1460,7 @@ static int sel_make_bools(struct selinux_fs_info *fsi) } isec = selinux_inode(inode); - ret = security_genfs_sid(fsi->state, "selinuxfs", page, + ret = selinux_policy_genfs_sid(newpolicy, "selinuxfs", page, SECCLASS_FILE, &sid); if (ret) { pr_warn_ratelimited("SELinux: no sid found, defaulting to security isid for %s\n", @@ -1402,9 +1474,9 @@ static int sel_make_bools(struct selinux_fs_info *fsi) inode->i_ino = i|SEL_BOOL_INO_OFFSET; d_add(dentry, inode); } - fsi->bool_num = num; - fsi->bool_pending_names = names; - fsi->bool_pending_values = values; + *bool_num = num; + *bool_pending_names = names; + *bool_pending_values = values; free_page((unsigned long)page); return 0; @@ -1417,7 +1489,7 @@ out: kfree(names); } kfree(values); - sel_remove_entries(dir); + sel_remove_entries(bool_dir); return ret; } @@ -1791,14 +1863,14 @@ static const struct file_operations sel_policycap_ops = { .llseek = generic_file_llseek, }; -static int sel_make_perm_files(char *objclass, int classvalue, - struct dentry *dir) +static int sel_make_perm_files(struct selinux_policy *newpolicy, + char *objclass, int classvalue, + struct dentry *dir) { - struct selinux_fs_info *fsi = dir->d_sb->s_fs_info; int i, rc, nperms; char **perms; - rc = security_get_permissions(fsi->state, objclass, &perms, &nperms); + rc = security_get_permissions(newpolicy, objclass, &perms, &nperms); if (rc) return rc; @@ -1831,8 +1903,9 @@ out: return rc; } -static int sel_make_class_dir_entries(char *classname, int index, - struct dentry *dir) +static int sel_make_class_dir_entries(struct selinux_policy *newpolicy, + char *classname, int index, + struct dentry *dir) { struct super_block *sb = dir->d_sb; struct selinux_fs_info *fsi = sb->s_fs_info; @@ -1858,39 +1931,38 @@ static int sel_make_class_dir_entries(char *classname, int index, if (IS_ERR(dentry)) return PTR_ERR(dentry); - rc = sel_make_perm_files(classname, index, dentry); + rc = sel_make_perm_files(newpolicy, classname, index, dentry); return rc; } -static int sel_make_classes(struct selinux_fs_info *fsi) +static int sel_make_classes(struct selinux_policy *newpolicy, + struct dentry *class_dir, + unsigned long *last_class_ino) { int rc, nclasses, i; char **classes; - /* delete any existing entries */ - sel_remove_entries(fsi->class_dir); - - rc = security_get_classes(fsi->state, &classes, &nclasses); + rc = security_get_classes(newpolicy, &classes, &nclasses); if (rc) return rc; /* +2 since classes are 1-indexed */ - fsi->last_class_ino = sel_class_to_ino(nclasses + 2); + *last_class_ino = sel_class_to_ino(nclasses + 2); for (i = 0; i < nclasses; i++) { struct dentry *class_name_dir; - class_name_dir = sel_make_dir(fsi->class_dir, classes[i], - &fsi->last_class_ino); + class_name_dir = sel_make_dir(class_dir, classes[i], + last_class_ino); if (IS_ERR(class_name_dir)) { rc = PTR_ERR(class_name_dir); goto out; } /* i+1 since class values are 1-indexed */ - rc = sel_make_class_dir_entries(classes[i], i + 1, + rc = sel_make_class_dir_entries(newpolicy, classes[i], i + 1, class_name_dir); if (rc) goto out; @@ -1909,8 +1981,6 @@ static int sel_make_policycap(struct selinux_fs_info *fsi) struct dentry *dentry = NULL; struct inode *inode = NULL; - sel_remove_entries(fsi->policycap_dir); - for (iter = 0; iter <= POLICYDB_CAPABILITY_MAX; iter++) { if (iter < ARRAY_SIZE(selinux_policycap_names)) dentry = d_alloc_name(fsi->policycap_dir, @@ -1962,6 +2032,22 @@ static struct dentry *sel_make_dir(struct dentry *dir, const char *name, return dentry; } +static struct dentry *sel_make_disconnected_dir(struct super_block *sb, + unsigned long *ino) +{ + struct inode *inode = sel_make_inode(sb, S_IFDIR | S_IRUGO | S_IXUGO); + + if (!inode) + return ERR_PTR(-ENOMEM); + + inode->i_op = &simple_dir_inode_operations; + inode->i_fop = &simple_dir_operations; + inode->i_ino = ++(*ino); + /* directory inodes start off with i_nlink == 2 (for "." entry) */ + inc_nlink(inode); + return d_obtain_alias(inode); +} + #define NULL_FILE_NAME "null" static int sel_fill_super(struct super_block *sb, struct fs_context *fc) @@ -2060,14 +2146,14 @@ static int sel_fill_super(struct super_block *sb, struct fs_context *fc) if (ret) goto err; - fsi->class_dir = sel_make_dir(sb->s_root, "class", &fsi->last_ino); + fsi->class_dir = sel_make_dir(sb->s_root, CLASS_DIR_NAME, &fsi->last_ino); if (IS_ERR(fsi->class_dir)) { ret = PTR_ERR(fsi->class_dir); fsi->class_dir = NULL; goto err; } - fsi->policycap_dir = sel_make_dir(sb->s_root, "policy_capabilities", + fsi->policycap_dir = sel_make_dir(sb->s_root, POLICYCAP_DIR_NAME, &fsi->last_ino); if (IS_ERR(fsi->policycap_dir)) { ret = PTR_ERR(fsi->policycap_dir); @@ -2075,9 +2161,12 @@ static int sel_fill_super(struct super_block *sb, struct fs_context *fc) goto err; } - ret = sel_make_policy_nodes(fsi); - if (ret) + ret = sel_make_policycap(fsi); + if (ret) { + pr_err("SELinux: failed to load policy capabilities\n"); goto err; + } + return 0; err: pr_err("SELinux: %s: failed while creating inodes\n", |