CVE-2021-47459

Updated on 22 May 2024

Severity

7.8 High severity

Details

CVSS score
7.8
CVSS vector
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H

Overview

About vulnerability

In the Linux kernel, the following vulnerability has been resolved:

can: j1939: j1939_netdev_start(): fix UAF for rx_kref of j1939_priv

It will trigger UAF for rx_kref of j1939_priv as following.

cpu0 cpu1 j1939_sk_bind(socket0, ndev0, …) j1939_netdev_start j1939_sk_bind(socket1, ndev0, …) j1939_netdev_start j1939_priv_set j1939_priv_get_by_ndev_locked j1939_jsk_add ….. j1939_netdev_stop kref_put_lock(&priv->rx_kref, …) kref_get(&priv->rx_kref, …) REFCOUNT_WARN(“addition on 0;…”)

==================================================== refcount_t: addition on 0; use-after-free. WARNING: CPU: 1 PID: 20874 at lib/refcount.c:25 refcount_warn_saturate+0x169/0x1e0 RIP: 0010:refcount_warn_saturate+0x169/0x1e0 Call Trace: j1939_netdev_start+0x68b/0x920 j1939_sk_bind+0x426/0xeb0 ? security_socket_bind+0x83/0xb0

The rx_kref’s kref_get() and kref_put() should use j1939_netdev_lock to protect.

Details

Affected packages:
kernel @ 2.6.32 (+9 more)

In the Linux kernel, the following vulnerability has been resolved:

can: j1939: j1939_netdev_start(): fix UAF for rx_kref of j1939_priv

It will trigger UAF for rx_kref of j1939_priv as following.

cpu0 cpu1 j1939_sk_bind(socket0, ndev0, …) j1939_netdev_start j1939_sk_bind(socket1, ndev0, …) j1939_netdev_start j1939_priv_set j1939_priv_get_by_ndev_locked j1939_jsk_add ….. j1939_netdev_stop kref_put_lock(&priv->rx_kref, …) kref_get(&priv->rx_kref, …) REFCOUNT_WARN(“addition on 0;…”)

==================================================== refcount_t: addition on 0; use-after-free. WARNING: CPU: 1 PID: 20874 at lib/refcount.c:25 refcount_warn_saturate+0x169/0x1e0 RIP: 0010:refcount_warn_saturate+0x169/0x1e0 Call Trace: j1939_netdev_start+0x68b/0x920 j1939_sk_bind+0x426/0xeb0 ? security_socket_bind+0x83/0xb0

The rx_kref’s kref_get() and kref_put() should use j1939_netdev_lock to protect.

Fixes