hi,
-----Original Message----- From: Parav Pandit parav@nvidia.com Sent: Thursday, October 31, 2024 12:15 PM To: Lege Wang lege.wang@jaguarmicro.com; virtualization@lists.linux.dev Cc: stable@vger.kernel.org; mst@redhat.com; jasowang@redhat.com Subject: RE: [PATCH] vp_vdpa: fix id_table array not null terminated error
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From: Xiaoguang Wang lege.wang@jaguarmicro.com Sent: Thursday, October 31, 2024 9:35 AM
Allocate one extra virtio_device_id as null terminator, otherwise vdpa_mgmtdev_get_classes() may iterate multiple times and visit undefined memory.
Fixes: ffbda8e9df10 ("vdpa/vp_vdpa : add vdpa tool support in vp_vdpa") Cc: stable@vger.kernel.org Signed-off-by: Xiaoguang Wang lege.wang@jaguarmicro.com
drivers/vdpa/virtio_pci/vp_vdpa.c | 6 +++++- 1 file changed, 5 insertions(+), 1 deletion(-)
diff --git a/drivers/vdpa/virtio_pci/vp_vdpa.c b/drivers/vdpa/virtio_pci/vp_vdpa.c index ac4ab22f7d8b..74cc4ed77cc4 100644 --- a/drivers/vdpa/virtio_pci/vp_vdpa.c +++ b/drivers/vdpa/virtio_pci/vp_vdpa.c @@ -612,7 +612,11 @@ static int vp_vdpa_probe(struct pci_dev *pdev, const struct pci_device_id *id) goto mdev_err; }
mdev_id = kzalloc(sizeof(struct virtio_device_id), GFP_KERNEL);
/** id_table should be a null terminated array.* See vdpa_mgmtdev_get_classes().*/mdev_id = kzalloc(sizeof(struct virtio_device_id) * 2, GFP_KERNEL);Only one additional entry is needed for null termination. No need to allocate 2x memory. Even though you have only two entries. Reading code as +1 is better to understand null termination.
Sorry, I don't get your point here, vp_vdpa_probe only needs one struct virtio_device_id, plus one null termination, "sizeof(struct virtio_device_id) * 2 " should be enough here?
And for array, you should use, array = kcalloc(2, sizeof(mdev_id), GFP_KERNEL);
OK, thanks for your suggestion.
Regards, Xiaoguang Wang
if (!mdev_id) { err = -ENOMEM; goto mdev_id_err;-- 2.40.1