[PATCH] virtio-pci: fix leaks of msix_affinity_masks

From: Andrey Vagin
Date: Thu Jun 20 2013 - 01:39:35 EST


From: Andrew Vagin <avagin@xxxxxxxxxx>

vp_dev->msix_vectors should be initialized before allocating
msix_affinity_masks, otherwise vp_free_vectors will not free these
objects.

unreferenced object 0xffff88010f969d88 (size 512):
comm "systemd-udevd", pid 158, jiffies 4294673645 (age 80.545s)
hex dump (first 32 bytes):
00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................
00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................
backtrace:
[<ffffffff816e455e>] kmemleak_alloc+0x5e/0xc0
[<ffffffff811aa7f1>] kmem_cache_alloc_node_trace+0x141/0x2c0
[<ffffffff8133ba23>] alloc_cpumask_var_node+0x23/0x80
[<ffffffff8133ba8e>] alloc_cpumask_var+0xe/0x10
[<ffffffff813fdb3d>] vp_try_to_find_vqs+0x25d/0x810
[<ffffffff813fe171>] vp_find_vqs+0x81/0xb0
[<ffffffffa00d2a05>] init_vqs+0x85/0x120 [virtio_balloon]
[<ffffffffa00d2c29>] virtballoon_probe+0xf9/0x1a0 [virtio_balloon]
[<ffffffff813fb61e>] virtio_dev_probe+0xde/0x140
[<ffffffff814452b8>] driver_probe_device+0x98/0x3a0
[<ffffffff8144566b>] __driver_attach+0xab/0xb0
[<ffffffff814432f4>] bus_for_each_dev+0x94/0xb0
[<ffffffff81444f4e>] driver_attach+0x1e/0x20
[<ffffffff81444910>] bus_add_driver+0x200/0x280
[<ffffffff81445c14>] driver_register+0x74/0x160
[<ffffffff813fb7d0>] register_virtio_driver+0x20/0x40

v2: change msix_vectors uncoditionaly in vp_free_vectors

Cc: Rusty Russell <rusty@xxxxxxxxxxxxxxx>
Cc: "Michael S. Tsirkin" <mst@xxxxxxxxxx>
Cc: Jason Wang <jasowang@xxxxxxxxxx>
Signed-off-by: Andrew Vagin <avagin@xxxxxxxxxx>
Signed-off-by: Andrey Vagin <avagin@xxxxxxxxxx>
---
drivers/virtio/virtio_pci.c | 5 +++--
1 file changed, 3 insertions(+), 2 deletions(-)

diff --git a/drivers/virtio/virtio_pci.c b/drivers/virtio/virtio_pci.c
index a7ce730..1aba255 100644
--- a/drivers/virtio/virtio_pci.c
+++ b/drivers/virtio/virtio_pci.c
@@ -289,9 +289,9 @@ static void vp_free_vectors(struct virtio_device *vdev)

pci_disable_msix(vp_dev->pci_dev);
vp_dev->msix_enabled = 0;
- vp_dev->msix_vectors = 0;
}

+ vp_dev->msix_vectors = 0;
vp_dev->msix_used_vectors = 0;
kfree(vp_dev->msix_names);
vp_dev->msix_names = NULL;
@@ -309,6 +309,8 @@ static int vp_request_msix_vectors(struct virtio_device *vdev, int nvectors,
unsigned i, v;
int err = -ENOMEM;

+ vp_dev->msix_vectors = nvectors;
+
vp_dev->msix_entries = kmalloc(nvectors * sizeof *vp_dev->msix_entries,
GFP_KERNEL);
if (!vp_dev->msix_entries)
@@ -336,7 +338,6 @@ static int vp_request_msix_vectors(struct virtio_device *vdev, int nvectors,
err = -ENOSPC;
if (err)
goto error;
- vp_dev->msix_vectors = nvectors;
vp_dev->msix_enabled = 1;

/* Set the vector used for configuration */
--
1.8.1.4

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