diff --git a/security/apparmor/apparmorfs.c b/security/apparmor/apparmorfs.c index 7a6ca7c5500d..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 @@ -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); @@ -453,7 +526,7 @@ 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); + 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); @@ -471,7 +544,7 @@ 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, f->f_cred); aa_put_ns(ns); @@ -491,7 +564,7 @@ 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 @@ -581,7 +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; @@ -1067,7 +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) { @@ -1259,7 +1332,7 @@ 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_i_loaddata(inode->i_private); + struct aa_loaddata *data = get_loaddata_common_ref(inode->i_private); int error; if (!data) @@ -1392,7 +1465,7 @@ static int rawdata_open(struct inode *inode, struct file *file) if (!aa_current_policy_view_capable(NULL)) return -EACCES; - loaddata = aa_get_i_loaddata(inode->i_private); + loaddata = get_loaddata_common_ref(inode->i_private); if (!loaddata) return -ENOENT; @@ -1437,7 +1510,6 @@ static void remove_rawdata_dents(struct aa_loaddata *rawdata) if (!IS_ERR_OR_NULL(rawdata->dents[i])) { aafs_remove(rawdata->dents[i]); rawdata->dents[i] = NULL; - aa_put_i_loaddata(rawdata); } } } @@ -1476,45 +1548,41 @@ int __aa_fs_create_rawdata(struct aa_ns *ns, struct aa_loaddata *rawdata) if (IS_ERR(dir)) /* ->name freed when rawdata freed */ return PTR_ERR(dir); - aa_get_i_loaddata(rawdata); 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; - aa_get_i_loaddata(rawdata); 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; - aa_get_i_loaddata(rawdata); 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; - aa_get_i_loaddata(rawdata); 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; - aa_get_i_loaddata(rawdata); 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; - aa_get_i_loaddata(rawdata); rawdata->dents[AAFS_LOADDATA_DATA] = dent; d_inode(dent)->i_size = rawdata->size; @@ -1525,7 +1593,6 @@ int __aa_fs_create_rawdata(struct aa_ns *ns, struct aa_loaddata *rawdata) fail: remove_rawdata_dents(rawdata); - aa_put_i_loaddata(rawdata); return PTR_ERR(dent); } #endif /* CONFIG_SECURITY_APPARMOR_EXPORT_BINARY */ @@ -1549,13 +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; } } @@ -1589,14 +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 @@ -1646,7 +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; @@ -1788,27 +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 */ @@ -1845,7 +1900,7 @@ static struct dentry *ns_mkdir_op(struct mnt_idmap *idmap, struct inode *dir, 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 @@ -1895,7 +1950,7 @@ static int ns_rmdir_op(struct inode *dir, struct dentry *dentry) 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. @@ -1965,27 +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; @@ -2010,40 +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; diff --git a/security/apparmor/include/label.h b/security/apparmor/include/label.h index c0812dbc1b5b..335f21930702 100644 --- a/security/apparmor/include/label.h +++ b/security/apparmor/include/label.h @@ -102,7 +102,7 @@ enum label_flags { struct aa_label; struct aa_proxy { - struct kref count; + struct aa_common_ref count; struct aa_label __rcu *label; }; @@ -125,7 +125,7 @@ struct label_it { * vec: vector of profiles comprising the compound label */ struct aa_label { - struct kref count; + struct aa_common_ref count; struct rb_node node; struct rcu_head rcu; struct aa_proxy *proxy; @@ -357,7 +357,7 @@ int aa_label_match(struct aa_profile *profile, struct aa_ruleset *rules, */ static inline struct aa_label *__aa_get_label(struct aa_label *l) { - if (l && kref_get_unless_zero(&l->count)) + if (l && kref_get_unless_zero(&l->count.count)) return l; return NULL; @@ -366,7 +366,7 @@ static inline struct aa_label *__aa_get_label(struct aa_label *l) static inline struct aa_label *aa_get_label(struct aa_label *l) { if (l) - kref_get(&(l->count)); + kref_get(&(l->count.count)); return l; } @@ -386,7 +386,7 @@ static inline struct aa_label *aa_get_label_rcu(struct aa_label __rcu **l) rcu_read_lock(); do { c = rcu_dereference(*l); - } while (c && !kref_get_unless_zero(&c->count)); + } while (c && !kref_get_unless_zero(&c->count.count)); rcu_read_unlock(); return c; @@ -426,7 +426,7 @@ static inline struct aa_label *aa_get_newest_label(struct aa_label *l) static inline void aa_put_label(struct aa_label *l) { if (l) - kref_put(&l->count, aa_label_kref); + kref_put(&l->count.count, aa_label_kref); } /* wrapper fn to indicate semantics of the check */ @@ -443,7 +443,7 @@ void aa_proxy_kref(struct kref *kref); static inline struct aa_proxy *aa_get_proxy(struct aa_proxy *proxy) { if (proxy) - kref_get(&(proxy->count)); + kref_get(&(proxy->count.count)); return proxy; } @@ -451,7 +451,7 @@ static inline struct aa_proxy *aa_get_proxy(struct aa_proxy *proxy) static inline void aa_put_proxy(struct aa_proxy *proxy) { if (proxy) - kref_put(&proxy->count, aa_proxy_kref); + kref_put(&proxy->count.count, aa_proxy_kref); } void __aa_proxy_redirect(struct aa_label *orig, struct aa_label *new); diff --git a/security/apparmor/include/lib.h b/security/apparmor/include/lib.h index 1c5d1f60f6a7..8c6ce8484552 100644 --- a/security/apparmor/include/lib.h +++ b/security/apparmor/include/lib.h @@ -102,6 +102,18 @@ void aa_info_message(const char *str); /* Security blob offsets */ extern struct lsm_blob_sizes apparmor_blob_sizes; +enum reftype { + REF_NS, + REF_PROXY, + REF_RAWDATA, +}; + +/* common reference count used by data the shows up in aafs */ +struct aa_common_ref { + struct kref count; + enum reftype reftype; +}; + /** * aa_strneq - compare null terminated @str to a non null terminated substring * @str: a null terminated string diff --git a/security/apparmor/include/policy.h b/security/apparmor/include/policy.h index fda9e75b8879..3895f8774a3f 100644 --- a/security/apparmor/include/policy.h +++ b/security/apparmor/include/policy.h @@ -379,7 +379,7 @@ static inline bool profile_mediates_safe(struct aa_profile *profile, static inline struct aa_profile *aa_get_profile(struct aa_profile *p) { if (p) - kref_get(&(p->label.count)); + kref_get(&(p->label.count.count)); return p; } @@ -393,7 +393,7 @@ static inline struct aa_profile *aa_get_profile(struct aa_profile *p) */ static inline struct aa_profile *aa_get_profile_not0(struct aa_profile *p) { - if (p && kref_get_unless_zero(&p->label.count)) + if (p && kref_get_unless_zero(&p->label.count.count)) return p; return NULL; @@ -413,7 +413,7 @@ static inline struct aa_profile *aa_get_profile_rcu(struct aa_profile __rcu **p) rcu_read_lock(); do { c = rcu_dereference(*p); - } while (c && !kref_get_unless_zero(&c->label.count)); + } while (c && !kref_get_unless_zero(&c->label.count.count)); rcu_read_unlock(); return c; @@ -426,7 +426,7 @@ static inline struct aa_profile *aa_get_profile_rcu(struct aa_profile __rcu **p) static inline void aa_put_profile(struct aa_profile *p) { if (p) - kref_put(&p->label.count, aa_label_kref); + kref_put(&p->label.count.count, aa_label_kref); } static inline int AUDIT_MODE(struct aa_profile *profile) diff --git a/security/apparmor/include/policy_unpack.h b/security/apparmor/include/policy_unpack.h index 4f800fbb805a..e5a95dc4da1f 100644 --- a/security/apparmor/include/policy_unpack.h +++ b/security/apparmor/include/policy_unpack.h @@ -108,7 +108,7 @@ struct aa_ext { * fs entries and drops the associated @count ref. */ struct aa_loaddata { - struct kref count; + struct aa_common_ref count; struct kref pcount; struct list_head list; struct work_struct work; @@ -143,7 +143,7 @@ aa_get_i_loaddata(struct aa_loaddata *data) { if (data) - kref_get(&(data->count)); + kref_get(&(data->count.count)); return data; } @@ -171,7 +171,7 @@ struct aa_loaddata *aa_loaddata_alloc(size_t size); static inline void aa_put_i_loaddata(struct aa_loaddata *data) { if (data) - kref_put(&data->count, aa_loaddata_kref); + kref_put(&data->count.count, aa_loaddata_kref); } static inline void aa_put_profile_loaddata(struct aa_loaddata *data) diff --git a/security/apparmor/label.c b/security/apparmor/label.c index e478283bc514..3a721fdf1833 100644 --- a/security/apparmor/label.c +++ b/security/apparmor/label.c @@ -52,7 +52,8 @@ static void free_proxy(struct aa_proxy *proxy) void aa_proxy_kref(struct kref *kref) { - struct aa_proxy *proxy = container_of(kref, struct aa_proxy, count); + struct aa_proxy *proxy = container_of(kref, struct aa_proxy, + count.count); free_proxy(proxy); } @@ -63,7 +64,8 @@ struct aa_proxy *aa_alloc_proxy(struct aa_label *label, gfp_t gfp) new = kzalloc_obj(struct aa_proxy, gfp); if (new) { - kref_init(&new->count); + kref_init(&new->count.count); + new->count.reftype = REF_PROXY; rcu_assign_pointer(new->label, aa_get_label(label)); } return new; @@ -375,7 +377,8 @@ static void label_free_rcu(struct rcu_head *head) void aa_label_kref(struct kref *kref) { - struct aa_label *label = container_of(kref, struct aa_label, count); + struct aa_label *label = container_of(kref, struct aa_label, + count.count); struct aa_ns *ns = labels_ns(label); if (!ns) { @@ -412,7 +415,8 @@ bool aa_label_init(struct aa_label *label, int size, gfp_t gfp) label->size = size; /* doesn't include null */ label->vec[size] = NULL; /* null terminate */ - kref_init(&label->count); + kref_init(&label->count.count); + label->count.reftype = REF_NS; /* for aafs purposes */ RB_CLEAR_NODE(&label->node); return true; diff --git a/security/apparmor/policy_unpack.c b/security/apparmor/policy_unpack.c index 69a040194e36..076d3ff14da6 100644 --- a/security/apparmor/policy_unpack.c +++ b/security/apparmor/policy_unpack.c @@ -119,7 +119,8 @@ static void do_loaddata_free(struct aa_loaddata *d) void aa_loaddata_kref(struct kref *kref) { - struct aa_loaddata *d = container_of(kref, struct aa_loaddata, count); + struct aa_loaddata *d = container_of(kref, struct aa_loaddata, + count.count); do_loaddata_free(d); } @@ -166,7 +167,8 @@ struct aa_loaddata *aa_loaddata_alloc(size_t size) kfree(d); return ERR_PTR(-ENOMEM); } - kref_init(&d->count); + kref_init(&d->count.count); + d->count.reftype = REF_RAWDATA; kref_init(&d->pcount); INIT_LIST_HEAD(&d->list);