vulnerability
Ubuntu: (CVE-2021-47459): linux vulnerability
| Severity | CVSS | Published | Added | Modified |
|---|---|---|---|---|
| 7 | (AV:L/AC:L/Au:S/C:C/I:C/A:C) | May 22, 2024 | Nov 19, 2024 | Sep 1, 2025 |
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.
Solutions
References
- CVE-2021-47459
- https://attackerkb.com/topics/CVE-2021-47459
- CWE-416
- URL-https://git.kernel.org/linus/d9d52a3ebd284882f5562c88e55991add5d01586
- URL-https://git.kernel.org/stable/c/6e8811707e2df0c6ba920f0cad3a3bca7b42132f
- URL-https://git.kernel.org/stable/c/864e77771a24c877aaf53aee019f78619cbcd668
- URL-https://git.kernel.org/stable/c/a0e47d2833b4f65e6c799f28c6b636d36b8b936d
- URL-https://git.kernel.org/stable/c/d9d52a3ebd284882f5562c88e55991add5d01586
- URL-https://www.cve.org/CVERecord?id=CVE-2021-47459
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