From patchwork Thu Dec 29 06:56:03 2016 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: "Reshetova, Elena" X-Patchwork-Id: 9491055 Return-Path: Received: from mail.wl.linuxfoundation.org (pdx-wl-mail.web.codeaurora.org [172.30.200.125]) by pdx-korg-patchwork.web.codeaurora.org (Postfix) with ESMTP id EE54560488 for ; Thu, 29 Dec 2016 06:58:29 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id DE1821FF65 for ; Thu, 29 Dec 2016 06:58:29 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id D154B2094F; Thu, 29 Dec 2016 06:58:29 +0000 (UTC) X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on pdx-wl-mail.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-4.2 required=2.0 tests=BAYES_00, RCVD_IN_DNSWL_MED autolearn=ham version=3.3.1 Received: from mother.openwall.net (mother.openwall.net [195.42.179.200]) by mail.wl.linuxfoundation.org (Postfix) with SMTP id 342C91FF65 for ; Thu, 29 Dec 2016 06:58:28 +0000 (UTC) Received: (qmail 28037 invoked by uid 550); 29 Dec 2016 06:57:33 -0000 Mailing-List: contact kernel-hardening-help@lists.openwall.com; run by ezmlm Precedence: bulk List-Post: List-Help: List-Unsubscribe: List-Subscribe: List-ID: Reply-To: kernel-hardening@lists.openwall.com Delivered-To: mailing list kernel-hardening@lists.openwall.com Received: (qmail 27966 invoked from network); 29 Dec 2016 06:57:32 -0000 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.33,425,1477983600"; d="scan'208";a="803215805" From: Elena Reshetova To: kernel-hardening@lists.openwall.com Cc: keescook@chromium.org, arnd@arndb.de, tglx@linutronix.de, mingo@redhat.com, h.peter.anvin@intel.com, peterz@infradead.org, will.deacon@arm.com, dwindsor@gmail.com, gregkh@linuxfoundation.org, ishkamiel@gmail.com, Elena Reshetova Date: Thu, 29 Dec 2016 08:56:03 +0200 Message-Id: <1482994571-18687-12-git-send-email-elena.reshetova@intel.com> X-Mailer: git-send-email 2.7.4 In-Reply-To: <1482994571-18687-1-git-send-email-elena.reshetova@intel.com> References: <1482994571-18687-1-git-send-email-elena.reshetova@intel.com> Subject: [kernel-hardening] [RFC PATCH 11/19] security: convert from atomic_t to refcount_t X-Virus-Scanned: ClamAV using ClamSMTP refcount_t type and corresponding API should be used instead of atomic_t when the variable is used as a reference counter. Convert the cases found. Signed-off-by: Elena Reshetova Signed-off-by: Hans Liljestrand --- include/linux/key.h | 5 +++-- security/keys/gc.c | 2 +- security/keys/internal.h | 3 ++- security/keys/key.c | 12 ++++++------ security/keys/keyring.c | 8 ++++---- security/keys/proc.c | 4 ++-- security/keys/process_keys.c | 2 +- security/keys/request_key_auth.c | 2 +- security/selinux/hooks.c | 9 +++++---- security/selinux/include/xfrm.h | 5 +++-- security/selinux/xfrm.c | 11 ++++++----- security/tomoyo/common.c | 11 ++++++----- 12 files changed, 40 insertions(+), 34 deletions(-) diff --git a/include/linux/key.h b/include/linux/key.h index 7229147..43d468e 100644 --- a/include/linux/key.h +++ b/include/linux/key.h @@ -23,6 +23,7 @@ #include #include #include +#include #ifdef __KERNEL__ #include @@ -135,7 +136,7 @@ static inline bool is_key_possessed(const key_ref_t key_ref) * - Kerberos TGTs and tickets */ struct key { - atomic_t usage; /* number of references */ + refcount_t usage; /* number of references */ key_serial_t serial; /* key serial number */ union { struct list_head graveyard_link; @@ -242,7 +243,7 @@ extern void key_put(struct key *key); static inline struct key *__key_get(struct key *key) { - atomic_inc(&key->usage); + refcount_inc(&key->usage); return key; } diff --git a/security/keys/gc.c b/security/keys/gc.c index addf060..4478925 100644 --- a/security/keys/gc.c +++ b/security/keys/gc.c @@ -220,7 +220,7 @@ static void key_garbage_collector(struct work_struct *work) key = rb_entry(cursor, struct key, serial_node); cursor = rb_next(cursor); - if (atomic_read(&key->usage) == 0) + if (refcount_read(&key->usage) == 0) goto found_unreferenced_key; if (unlikely(gc_state & KEY_GC_REAPING_DEAD_1)) { diff --git a/security/keys/internal.h b/security/keys/internal.h index a705a7d..110d661 100644 --- a/security/keys/internal.h +++ b/security/keys/internal.h @@ -16,6 +16,7 @@ #include #include #include +#include struct iovec; @@ -52,7 +53,7 @@ struct key_user { struct rb_node node; struct mutex cons_lock; /* construction initiation lock */ spinlock_t lock; - atomic_t usage; /* for accessing qnkeys & qnbytes */ + refcount_t usage; /* for accessing qnkeys & qnbytes */ atomic_t nkeys; /* number of keys */ atomic_t nikeys; /* number of instantiated keys */ kuid_t uid; diff --git a/security/keys/key.c b/security/keys/key.c index 346fbf2..b4958b3 100644 --- a/security/keys/key.c +++ b/security/keys/key.c @@ -93,7 +93,7 @@ struct key_user *key_user_lookup(kuid_t uid) /* if we get here, then the user record still hadn't appeared on the * second pass - so we use the candidate record */ - atomic_set(&candidate->usage, 1); + refcount_set(&candidate->usage, 1); atomic_set(&candidate->nkeys, 0); atomic_set(&candidate->nikeys, 0); candidate->uid = uid; @@ -110,7 +110,7 @@ struct key_user *key_user_lookup(kuid_t uid) /* okay - we found a user record for this UID */ found: - atomic_inc(&user->usage); + refcount_inc(&user->usage); spin_unlock(&key_user_lock); kfree(candidate); out: @@ -122,7 +122,7 @@ struct key_user *key_user_lookup(kuid_t uid) */ void key_user_put(struct key_user *user) { - if (atomic_dec_and_lock(&user->usage, &key_user_lock)) { + if (refcount_dec_and_lock(&user->usage, &key_user_lock)) { rb_erase(&user->node, &key_user_tree); spin_unlock(&key_user_lock); @@ -285,7 +285,7 @@ struct key *key_alloc(struct key_type *type, const char *desc, if (!key->index_key.description) goto no_memory_3; - atomic_set(&key->usage, 1); + refcount_set(&key->usage, 1); init_rwsem(&key->sem); lockdep_set_class(&key->sem, &type->lock_class); key->index_key.type = type; @@ -621,7 +621,7 @@ void key_put(struct key *key) if (key) { key_check(key); - if (atomic_dec_and_test(&key->usage)) + if (refcount_dec_and_test(&key->usage)) schedule_work(&key_gc_work); } } @@ -656,7 +656,7 @@ struct key *key_lookup(key_serial_t id) found: /* pretend it doesn't exist if it is awaiting deletion */ - if (atomic_read(&key->usage) == 0) + if (refcount_read(&key->usage) == 0) goto not_found; /* this races with key_put(), but that doesn't matter since key_put() diff --git a/security/keys/keyring.c b/security/keys/keyring.c index c91e4e0..3d95f7d 100644 --- a/security/keys/keyring.c +++ b/security/keys/keyring.c @@ -1033,7 +1033,7 @@ struct key *find_keyring_by_name(const char *name, bool skip_perm_check) /* we've got a match but we might end up racing with * key_cleanup() if the keyring is currently 'dead' * (ie. it has a zero usage count) */ - if (!atomic_inc_not_zero(&keyring->usage)) + if (!refcount_inc_not_zero(&keyring->usage)) continue; keyring->last_used_at = current_kernel_time().tv_sec; goto out; @@ -1250,14 +1250,14 @@ int key_link(struct key *keyring, struct key *key) struct assoc_array_edit *edit; int ret; - kenter("{%d,%d}", keyring->serial, atomic_read(&keyring->usage)); + kenter("{%d,%d}", keyring->serial, refcount_read(&keyring->usage)); key_check(keyring); key_check(key); ret = __key_link_begin(keyring, &key->index_key, &edit); if (ret == 0) { - kdebug("begun {%d,%d}", keyring->serial, atomic_read(&keyring->usage)); + kdebug("begun {%d,%d}", keyring->serial, refcount_read(&keyring->usage)); ret = __key_link_check_restriction(keyring, key); if (ret == 0) ret = __key_link_check_live_key(keyring, key); @@ -1266,7 +1266,7 @@ int key_link(struct key *keyring, struct key *key) __key_link_end(keyring, &key->index_key, edit); } - kleave(" = %d {%d,%d}", ret, keyring->serial, atomic_read(&keyring->usage)); + kleave(" = %d {%d,%d}", ret, keyring->serial, refcount_read(&keyring->usage)); return ret; } EXPORT_SYMBOL(key_link); diff --git a/security/keys/proc.c b/security/keys/proc.c index b9f531c..bf08d02 100644 --- a/security/keys/proc.c +++ b/security/keys/proc.c @@ -252,7 +252,7 @@ static int proc_keys_show(struct seq_file *m, void *v) showflag(key, 'U', KEY_FLAG_USER_CONSTRUCT), showflag(key, 'N', KEY_FLAG_NEGATIVE), showflag(key, 'i', KEY_FLAG_INVALIDATED), - atomic_read(&key->usage), + refcount_read(&key->usage), xbuf, key->perm, from_kuid_munged(seq_user_ns(m), key->uid), @@ -340,7 +340,7 @@ static int proc_key_users_show(struct seq_file *m, void *v) seq_printf(m, "%5u: %5d %d/%d %d/%d %d/%d\n", from_kuid_munged(seq_user_ns(m), user->uid), - atomic_read(&user->usage), + refcount_read(&user->usage), atomic_read(&user->nkeys), atomic_read(&user->nikeys), user->qnkeys, diff --git a/security/keys/process_keys.c b/security/keys/process_keys.c index 40a8852..31c9e2a 100644 --- a/security/keys/process_keys.c +++ b/security/keys/process_keys.c @@ -29,7 +29,7 @@ static DEFINE_MUTEX(key_user_keyring_mutex); /* The root user's tracking struct */ struct key_user root_key_user = { - .usage = ATOMIC_INIT(3), + .usage = REFCOUNT_INIT(3), .cons_lock = __MUTEX_INITIALIZER(root_key_user.cons_lock), .lock = __SPIN_LOCK_UNLOCKED(root_key_user.lock), .nkeys = ATOMIC_INIT(2), diff --git a/security/keys/request_key_auth.c b/security/keys/request_key_auth.c index 9db8b4a..415bddc 100644 --- a/security/keys/request_key_auth.c +++ b/security/keys/request_key_auth.c @@ -213,7 +213,7 @@ struct key *request_key_auth_new(struct key *target, const void *callout_info, if (ret < 0) goto error_inst; - kleave(" = {%d,%d}", authkey->serial, atomic_read(&authkey->usage)); + kleave(" = {%d,%d}", authkey->serial, refcount_read(&authkey->usage)); return authkey; auth_key_revoked: diff --git a/security/selinux/hooks.c b/security/selinux/hooks.c index c7c6619..1241b07 100644 --- a/security/selinux/hooks.c +++ b/security/selinux/hooks.c @@ -83,6 +83,7 @@ #include #include #include +#include #include "avc.h" #include "objsec.h" @@ -95,7 +96,7 @@ #include "avc_ss.h" /* SECMARK reference count */ -static atomic_t selinux_secmark_refcount = ATOMIC_INIT(0); +static refcount_t selinux_secmark_refcount = REFCOUNT_INIT(0); #ifdef CONFIG_SECURITY_SELINUX_DEVELOP int selinux_enforcing; @@ -141,7 +142,7 @@ static struct kmem_cache *file_security_cache; */ static int selinux_secmark_enabled(void) { - return (selinux_policycap_alwaysnetwork || atomic_read(&selinux_secmark_refcount)); + return (selinux_policycap_alwaysnetwork || refcount_read(&selinux_secmark_refcount)); } /** @@ -4915,12 +4916,12 @@ static int selinux_secmark_relabel_packet(u32 sid) static void selinux_secmark_refcount_inc(void) { - atomic_inc(&selinux_secmark_refcount); + refcount_inc(&selinux_secmark_refcount); } static void selinux_secmark_refcount_dec(void) { - atomic_dec(&selinux_secmark_refcount); + refcount_dec(&selinux_secmark_refcount); } static void selinux_req_classify_flow(const struct request_sock *req, diff --git a/security/selinux/include/xfrm.h b/security/selinux/include/xfrm.h index 1450f85..182dc95 100644 --- a/security/selinux/include/xfrm.h +++ b/security/selinux/include/xfrm.h @@ -8,6 +8,7 @@ #define _SELINUX_XFRM_H_ #include +#include int selinux_xfrm_policy_alloc(struct xfrm_sec_ctx **ctxp, struct xfrm_user_sec_ctx *uctx, @@ -28,11 +29,11 @@ int selinux_xfrm_state_pol_flow_match(struct xfrm_state *x, const struct flowi *fl); #ifdef CONFIG_SECURITY_NETWORK_XFRM -extern atomic_t selinux_xfrm_refcount; +extern refcount_t selinux_xfrm_refcount; static inline int selinux_xfrm_enabled(void) { - return (atomic_read(&selinux_xfrm_refcount) > 0); + return (refcount_read(&selinux_xfrm_refcount) > 0); } int selinux_xfrm_sock_rcv_skb(u32 sk_sid, struct sk_buff *skb, diff --git a/security/selinux/xfrm.c b/security/selinux/xfrm.c index 56e354f..f485965 100644 --- a/security/selinux/xfrm.c +++ b/security/selinux/xfrm.c @@ -44,13 +44,14 @@ #include #include #include +#include #include "avc.h" #include "objsec.h" #include "xfrm.h" /* Labeled XFRM instance counter */ -atomic_t selinux_xfrm_refcount = ATOMIC_INIT(0); +refcount_t selinux_xfrm_refcount = REFCOUNT_INIT(0); /* * Returns true if the context is an LSM/SELinux context. @@ -111,7 +112,7 @@ static int selinux_xfrm_alloc_user(struct xfrm_sec_ctx **ctxp, goto err; *ctxp = ctx; - atomic_inc(&selinux_xfrm_refcount); + refcount_inc(&selinux_xfrm_refcount); return 0; err: @@ -127,7 +128,7 @@ static void selinux_xfrm_free(struct xfrm_sec_ctx *ctx) if (!ctx) return; - atomic_dec(&selinux_xfrm_refcount); + refcount_dec(&selinux_xfrm_refcount); kfree(ctx); } @@ -302,7 +303,7 @@ int selinux_xfrm_policy_clone(struct xfrm_sec_ctx *old_ctx, GFP_ATOMIC); if (!new_ctx) return -ENOMEM; - atomic_inc(&selinux_xfrm_refcount); + refcount_inc(&selinux_xfrm_refcount); *new_ctxp = new_ctx; return 0; @@ -369,7 +370,7 @@ int selinux_xfrm_state_alloc_acquire(struct xfrm_state *x, memcpy(ctx->ctx_str, ctx_str, str_len); x->security = ctx; - atomic_inc(&selinux_xfrm_refcount); + refcount_inc(&selinux_xfrm_refcount); out: kfree(ctx_str); return rc; diff --git a/security/tomoyo/common.c b/security/tomoyo/common.c index e0fb750..9a7605a 100644 --- a/security/tomoyo/common.c +++ b/security/tomoyo/common.c @@ -7,6 +7,7 @@ #include #include #include +#include #include "common.h" /* String table for operation mode. */ @@ -1907,7 +1908,7 @@ static DEFINE_SPINLOCK(tomoyo_query_list_lock); * Number of "struct file" referring /sys/kernel/security/tomoyo/query * interface. */ -static atomic_t tomoyo_query_observers = ATOMIC_INIT(0); +static refcount_t tomoyo_query_observers = REFCOUNT_INIT(0); /** * tomoyo_truncate - Truncate a line. @@ -2015,7 +2016,7 @@ int tomoyo_supervisor(struct tomoyo_request_info *r, const char *fmt, ...) switch (r->mode) { case TOMOYO_CONFIG_ENFORCING: error = -EPERM; - if (atomic_read(&tomoyo_query_observers)) + if (refcount_read(&tomoyo_query_observers)) break; goto out; case TOMOYO_CONFIG_LEARNING: @@ -2059,7 +2060,7 @@ int tomoyo_supervisor(struct tomoyo_request_info *r, const char *fmt, ...) wake_up_all(&tomoyo_query_wait); if (wait_event_interruptible_timeout (tomoyo_answer_wait, entry.answer || - !atomic_read(&tomoyo_query_observers), HZ)) + !refcount_read(&tomoyo_query_observers), HZ)) break; else entry.timer++; @@ -2437,7 +2438,7 @@ int tomoyo_open_control(const u8 type, struct file *file) * there is some process monitoring /sys/kernel/security/tomoyo/query. */ if (type == TOMOYO_QUERY) - atomic_inc(&tomoyo_query_observers); + refcount_inc(&tomoyo_query_observers); file->private_data = head; tomoyo_notify_gc(head, true); return 0; @@ -2687,7 +2688,7 @@ void tomoyo_close_control(struct tomoyo_io_buffer *head) * observer counter. */ if (head->type == TOMOYO_QUERY && - atomic_dec_and_test(&tomoyo_query_observers)) + refcount_dec_and_test(&tomoyo_query_observers)) wake_up_all(&tomoyo_answer_wait); tomoyo_notify_gc(head, false); }