Received-SPF: pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 23.128.96.18 as permitted sender) client-ip=23.128.96.18;
From:   Sasha Levin <sashal@kernel.org>
To:     linux-kernel@vger.kernel.org, stable@vger.kernel.org
Cc:     Zenghui Yu <yuzenghui@huawei.com>, Marc Zyngier <maz@kernel.org>,
        Sasha Levin <sashal@kernel.org>,
        linux-arm-kernel@lists.infradead.org, kvmarm@lists.cs.columbia.edu,
        kvm@vger.kernel.org
Subject: [PATCH AUTOSEL 5.4 243/330] KVM: arm64: vgic-its: Fix memory leak on the error path of vgic_add_lpi()
Date:   Thu, 17 Sep 2020 21:59:43 -0400
Message-Id: <20200918020110.2063155-243-sashal@kernel.org>
In-Reply-To: <20200918020110.2063155-1-sashal@kernel.org>
References: <20200918020110.2063155-1-sashal@kernel.org>
MIME-Version: 1.0
Content-Transfer-Encoding: 8bit
Precedence: bulk

From: Zenghui Yu <yuzenghui@huawei.com>

[ Upstream commit 57bdb436ce869a45881d8aa4bc5dac8e072dd2b6 ]

If we're going to fail out the vgic_add_lpi(), let's make sure the
allocated vgic_irq memory is also freed. Though it seems that both
cases are unlikely to fail.

Signed-off-by: Zenghui Yu <yuzenghui@huawei.com>
Signed-off-by: Marc Zyngier <maz@kernel.org>
Link: https://lore.kernel.org/r/20200414030349.625-3-yuzenghui@huawei.com
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
 virt/kvm/arm/vgic/vgic-its.c | 11 +++++++++--
 1 file changed, 9 insertions(+), 2 deletions(-)

diff --git a/virt/kvm/arm/vgic/vgic-its.c b/virt/kvm/arm/vgic/vgic-its.c
index f8ad7096555d7..35be0e2a46393 100644
--- a/virt/kvm/arm/vgic/vgic-its.c
+++ b/virt/kvm/arm/vgic/vgic-its.c
@@ -96,14 +96,21 @@ out_unlock:
 	 * We "cache" the configuration table entries in our struct vgic_irq's.
 	 * However we only have those structs for mapped IRQs, so we read in
 	 * the respective config data from memory here upon mapping the LPI.
+	 *
+	 * Should any of these fail, behave as if we couldn't create the LPI
+	 * by dropping the refcount and returning the error.
 	 */
 	ret = update_lpi_config(kvm, irq, NULL, false);
-	if (ret)
+	if (ret) {
+		vgic_put_irq(kvm, irq);
 		return ERR_PTR(ret);
+	}
 
 	ret = vgic_v3_lpi_sync_pending_status(kvm, irq);
-	if (ret)
+	if (ret) {
+		vgic_put_irq(kvm, irq);
 		return ERR_PTR(ret);
+	}
 
 	return irq;
 }
-- 
2.25.1