linux-kernel - [PATCH 1/2] KVM: lib: use jump label to handle resource release in irq_bypass_register

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:   Fri, 6 Dec 2019 10:53:52 +0800
From:   linmiaohe <linmiaohe@...wei.com>
To:     <pbonzini@...hat.com>, <alex.williamson@...hat.com>
CC:     <linmiaohe@...wei.com>, <kvm@...r.kernel.org>,
        <linux-kernel@...r.kernel.org>
Subject: [PATCH 1/2] KVM: lib: use jump label to handle resource release in irq_bypass_register_consumer()

From: Miaohe Lin <linmiaohe@...wei.com>

Use out_err jump label to handle resource release. It's a
good practice to release resource in one place and help
eliminate some duplicated code.

Signed-off-by: Miaohe Lin <linmiaohe@...wei.com>
---
 virt/lib/irqbypass.c | 19 ++++++++++---------
 1 file changed, 10 insertions(+), 9 deletions(-)

diff --git a/virt/lib/irqbypass.c b/virt/lib/irqbypass.c
index 43de8ae78fa1..cb0c801b3bc2 100644
--- a/virt/lib/irqbypass.c
+++ b/virt/lib/irqbypass.c
@@ -179,6 +179,7 @@ int irq_bypass_register_consumer(struct irq_bypass_consumer *consumer)
 {
 	struct irq_bypass_consumer *tmp;
 	struct irq_bypass_producer *producer;
+	int ret;
 
 	if (!consumer->token ||
 	    !consumer->add_producer || !consumer->del_producer)
@@ -193,20 +194,16 @@ int irq_bypass_register_consumer(struct irq_bypass_consumer *consumer)
 
 	list_for_each_entry(tmp, &consumers, node) {
 		if (tmp->token == consumer->token || tmp == consumer) {
-			mutex_unlock(&lock);
-			module_put(THIS_MODULE);
-			return -EBUSY;
+			ret = -EBUSY;
+			goto out_err;
 		}
 	}
 
 	list_for_each_entry(producer, &producers, node) {
 		if (producer->token == consumer->token) {
-			int ret = __connect(producer, consumer);
-			if (ret) {
-				mutex_unlock(&lock);
-				module_put(THIS_MODULE);
-				return ret;
-			}
+			ret = __connect(producer, consumer);
+			if (ret)
+				goto out_err;
 			break;
 		}
 	}
@@ -216,6 +213,10 @@ int irq_bypass_register_consumer(struct irq_bypass_consumer *consumer)
 	mutex_unlock(&lock);
 
 	return 0;
+out_err:
+	mutex_unlock(&lock);
+	module_put(THIS_MODULE);
+	return ret;
 }
 EXPORT_SYMBOL_GPL(irq_bypass_register_consumer);
 
-- 
2.19.1