vulnerability
Debian: CVE-2021-47459: linux -- security update
| Severity | CVSS | Published | Added | Modified |
|---|---|---|---|---|
| 7 | (AV:L/AC:L/Au:S/C:C/I:C/A:C) | 2024-05-22 | 2024-07-30 | 2025-01-30 |
Description
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.
Solution
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