[PATCH 2/4] vdpa: Add queue index attr to vdpa_nl_policy for nlattr length check

From: Dragos Tatulea
Date: Thu Jul 27 2023 - 13:58:44 EST


From: Lin Ma <linma@xxxxxxxxxx>

The vdpa_nl_policy structure is used to validate the nlattr when parsing
the incoming nlmsg. It will ensure the attribute being described produces
a valid nlattr pointer in info->attrs before entering into each handler
in vdpa_nl_ops.

That is to say, the missing part in vdpa_nl_policy may lead to illegal
nlattr after parsing, which could lead to OOB read just like CVE-2023-3773.

This patch adds the missing nla_policy for vdpa queue index attr to avoid
such bugs.

Fixes: 13b00b135665 ("vdpa: Add support for querying vendor statistics")
Signed-off-by: Lin Ma <linma@xxxxxxxxxx>
Cc: stable@vger.kernelorg
---
drivers/vdpa/vdpa.c | 1 +
1 file changed, 1 insertion(+)

diff --git a/drivers/vdpa/vdpa.c b/drivers/vdpa/vdpa.c
index 3ad355a2208a..75f1df2b9d2a 100644
--- a/drivers/vdpa/vdpa.c
+++ b/drivers/vdpa/vdpa.c
@@ -1249,6 +1249,7 @@ static const struct nla_policy vdpa_nl_policy[VDPA_ATTR_MAX + 1] = {
[VDPA_ATTR_DEV_NET_CFG_MACADDR] = NLA_POLICY_ETH_ADDR,
/* virtio spec 1.1 section 5.1.4.1 for valid MTU range */
[VDPA_ATTR_DEV_NET_CFG_MTU] = NLA_POLICY_MIN(NLA_U16, 68),
+ [VDPA_ATTR_DEV_QUEUE_INDEX] = { .type = NLA_U32 },
[VDPA_ATTR_DEV_FEATURES] = { .type = NLA_U64 },
};

--
2.41.0