Use After Free Affecting kernel-core package, versions <0:5.14.0-284.75.1.el9_2
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Test your applications- Snyk ID SNYK-RHEL9-KERNELCORE-7559377
- published 25 Jul 2024
- disclosed 22 May 2024
Introduced: 22 May 2024
CVE-2021-47459 Open this link in a new tabHow to fix?
Upgrade RHEL:9 kernel-core to version 0:5.14.0-284.75.1.el9_2 or higher.
This issue was patched in RHSA-2024:4823.
NVD Description
Note: Versions mentioned in the description apply only to the upstream kernel-core package and not the kernel-core package as distributed by RHEL.
See How to fix? for RHEL:9 relevant fixed versions and status.
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.
References
- https://access.redhat.com/security/cve/CVE-2021-47459
- https://git.kernel.org/stable/c/6e8811707e2df0c6ba920f0cad3a3bca7b42132f
- https://git.kernel.org/stable/c/864e77771a24c877aaf53aee019f78619cbcd668
- https://git.kernel.org/stable/c/a0e47d2833b4f65e6c799f28c6b636d36b8b936d
- https://git.kernel.org/stable/c/d9d52a3ebd284882f5562c88e55991add5d01586