linux-kernel - [PATCH 2/5] firmware: fix capturing errors on fw_cache

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Date:   Mon, 20 Nov 2017 09:45:32 -0800
From:   "Luis R. Rodriguez" <mcgrof@...nel.org>
To:     gregkh@...uxfoundation.org
Cc:     keescook@...omium.org, mfuzzey@...keon.com,
        zohar@...ux.vnet.ibm.com, dhowells@...hat.com,
        pali.rohar@...il.com, tiwai@...e.de, arend.vanspriel@...adcom.com,
        zajec5@...il.com, nbroeking@...com, markivx@...eaurora.org,
        stephen.boyd@...aro.org, broonie@...nel.org,
        dmitry.torokhov@...il.com, dwmw2@...radead.org,
        torvalds@...ux-foundation.org, Abhay_Salunke@...l.com,
        bjorn.andersson@...aro.org, jewalt@...innovations.com,
        linux-kernel@...r.kernel.org, linux-fsdevel@...r.kernel.org,
        "Luis R. Rodriguez" <mcgrof@...nel.org>
Subject: [PATCH 2/5] firmware: fix capturing errors on fw_cache_init() on early init

register_pm_notifier() can technically fail, caputure this.
Note that register_syscore_ops() cannot fail given it just
adds an element to a linked list. This has been broken since
v3.7. Chances of this failing however are slim.

To improve code readability move the code folded under CONFIG_PM_SLEEP
into a helper.

Fixes: 07646d9c0938d ("firmware loader: cache devices firmware during suspend/resume cycle")
Signed-off-by: Luis R. Rodriguez <mcgrof@...nel.org>
---
 drivers/base/firmware_class.c | 45 ++++++++++++++++++++++++++++++-------------
 1 file changed, 32 insertions(+), 13 deletions(-)

diff --git a/drivers/base/firmware_class.c b/drivers/base/firmware_class.c
index 149413a376cf..c8033c5488f9 100644
--- a/drivers/base/firmware_class.c
+++ b/drivers/base/firmware_class.c
@@ -1768,6 +1768,26 @@ static struct syscore_ops fw_syscore_ops = {
 	.suspend = fw_suspend,
 };
 
+static int __init register_fw_pm_ops(void)
+{
+	int ret;
+
+	spin_lock_init(&fw_cache.name_lock);
+	INIT_LIST_HEAD(&fw_cache.fw_names);
+
+	INIT_DELAYED_WORK(&fw_cache.work,
+			  device_uncache_fw_images_work);
+
+	fw_cache.pm_notify.notifier_call = fw_pm_notify;
+	ret = register_pm_notifier(&fw_cache.pm_notify);
+	if (ret)
+		return ret;
+
+	register_syscore_ops(&fw_syscore_ops);
+
+	return ret;
+}
+
 static inline void unregister_fw_pm_ops(void)
 {
 	unregister_syscore_ops(&fw_syscore_ops);
@@ -1778,6 +1798,10 @@ static int fw_cache_piggyback_on_request(const char *name)
 {
 	return 0;
 }
+static inline int register_fw_pm_ops(void)
+{
+	return 0;
+}
 static inline void unregister_fw_pm_ops(void)
 {
 }
@@ -1788,19 +1812,6 @@ static void __init fw_cache_init(void)
 	spin_lock_init(&fw_cache.lock);
 	INIT_LIST_HEAD(&fw_cache.head);
 	fw_cache.state = FW_LOADER_NO_CACHE;
-
-#ifdef CONFIG_PM_SLEEP
-	spin_lock_init(&fw_cache.name_lock);
-	INIT_LIST_HEAD(&fw_cache.fw_names);
-
-	INIT_DELAYED_WORK(&fw_cache.work,
-			  device_uncache_fw_images_work);
-
-	fw_cache.pm_notify.notifier_call = fw_pm_notify;
-	register_pm_notifier(&fw_cache.pm_notify);
-
-	register_syscore_ops(&fw_syscore_ops);
-#endif
 }
 
 static int fw_shutdown_notify(struct notifier_block *unused1,
@@ -1821,7 +1832,15 @@ static struct notifier_block fw_shutdown_nb = {
 
 static int __init firmware_class_init(void)
 {
+	int ret;
+
+	/* No need to unfold these on exit */
 	fw_cache_init();
+
+	ret = register_fw_pm_ops();
+	if (ret)
+		return ret;
+
 	register_reboot_notifier(&fw_shutdown_nb);
 #ifdef CONFIG_FW_LOADER_USER_HELPER
 	return class_register(&firmware_class);
-- 
2.15.0