linux-kernel - [PATCH 5.10 047/157] vhost_vdpa: fix the missing irq_bypass_unregister

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, 22 Mar 2021 13:26:44 +0100
From:   Greg Kroah-Hartman <gregkh@...uxfoundation.org>
To:     linux-kernel@...r.kernel.org
Cc:     Greg Kroah-Hartman <gregkh@...uxfoundation.org>,
        stable@...r.kernel.org, Gautam Dawar <gdawar.xilinx@...il.com>,
        Jason Wang <jasowang@...hat.com>,
        "Michael S. Tsirkin" <mst@...hat.com>
Subject: [PATCH 5.10 047/157] vhost_vdpa: fix the missing irq_bypass_unregister_producer() invocation

From: Gautam Dawar <gdawar.xilinx@...il.com>

commit 4c050286bb202cffd5467c1cba982dff391d62e1 upstream.

When qemu with vhost-vdpa netdevice is run for the first time,
it works well. But after the VM is powered off, the next qemu run
causes kernel panic due to a NULL pointer dereference in
irq_bypass_register_producer().

When the VM is powered off, vhost_vdpa_clean_irq() misses on calling
irq_bypass_unregister_producer() for irq 0 because of the existing check.

This leaves stale producer nodes, which are reset in
vhost_vring_call_reset() when vhost_dev_init() is invoked during the
second qemu run.

As the node member of struct irq_bypass_producer is also initialized
to zero, traversal on the producers list causes crash due to NULL
pointer dereference.

Fixes: 2cf1ba9a4d15c ("vhost_vdpa: implement IRQ offloading in vhost_vdpa")
Bugzilla: https://bugzilla.kernel.org/show_bug.cgi?id=211711
Signed-off-by: Gautam Dawar <gdawar.xilinx@...il.com>
Acked-by: Jason Wang <jasowang@...hat.com>
Link: https://lore.kernel.org/r/20210224114845.104173-1-gdawar.xilinx@gmail.com
Signed-off-by: Michael S. Tsirkin <mst@...hat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@...uxfoundation.org>
---
 drivers/vhost/vdpa.c |    8 ++------
 1 file changed, 2 insertions(+), 6 deletions(-)

--- a/drivers/vhost/vdpa.c
+++ b/drivers/vhost/vdpa.c
@@ -910,14 +910,10 @@ err:
 
 static void vhost_vdpa_clean_irq(struct vhost_vdpa *v)
 {
-	struct vhost_virtqueue *vq;
 	int i;
 
-	for (i = 0; i < v->nvqs; i++) {
-		vq = &v->vqs[i];
-		if (vq->call_ctx.producer.irq)
-			irq_bypass_unregister_producer(&vq->call_ctx.producer);
-	}
+	for (i = 0; i < v->nvqs; i++)
+		vhost_vdpa_unsetup_vq_irq(v, i);
 }
 
 static int vhost_vdpa_release(struct inode *inode, struct file *filep)