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:   Greg Kroah-Hartman <gregkh@linuxfoundation.org>
To:     linux-kernel@vger.kernel.org
Cc:     Greg Kroah-Hartman <gregkh@linuxfoundation.org>,
        stable@vger.kernel.org,
        Stefano Stabellini <stefano.stabellini@xilinx.com>,
        Julien Grall <jgrall@amazon.com>,
        Juergen Gross <jgross@suse.com>
Subject: [PATCH 5.4 08/13] xen/arm: dont ignore return errors from set_phys_to_machine
Date:   Mon, 22 Feb 2021 13:13:25 +0100
Message-Id: <20210222121018.539342040@linuxfoundation.org>
In-Reply-To: <20210222121013.583922436@linuxfoundation.org>
References: <20210222121013.583922436@linuxfoundation.org>
User-Agent: quilt/0.66
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit
Precedence: bulk

From: Stefano Stabellini <stefano.stabellini@xilinx.com>

commit 36bf1dfb8b266e089afa9b7b984217f17027bf35 upstream.

set_phys_to_machine can fail due to lack of memory, see the kzalloc call
in arch/arm/xen/p2m.c:__set_phys_to_machine_multi.

Don't ignore the potential return error in set_foreign_p2m_mapping,
returning it to the caller instead.

This is part of XSA-361.

Signed-off-by: Stefano Stabellini <stefano.stabellini@xilinx.com>
Cc: stable@vger.kernel.org
Reviewed-by: Julien Grall <jgrall@amazon.com>
Signed-off-by: Juergen Gross <jgross@suse.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

---
 arch/arm/xen/p2m.c |    6 ++++--
 1 file changed, 4 insertions(+), 2 deletions(-)

--- a/arch/arm/xen/p2m.c
+++ b/arch/arm/xen/p2m.c
@@ -95,8 +95,10 @@ int set_foreign_p2m_mapping(struct gntta
 	for (i = 0; i < count; i++) {
 		if (map_ops[i].status)
 			continue;
-		set_phys_to_machine(map_ops[i].host_addr >> XEN_PAGE_SHIFT,
-				    map_ops[i].dev_bus_addr >> XEN_PAGE_SHIFT);
+		if (unlikely(!set_phys_to_machine(map_ops[i].host_addr >> XEN_PAGE_SHIFT,
+				    map_ops[i].dev_bus_addr >> XEN_PAGE_SHIFT))) {
+			return -ENOMEM;
+		}
 	}
 
 	return 0;