Description

In the Linux kernel, the following vulnerability has been resolved: net: caif: clear client service pointer on teardown `caif_connect()` can tear down an existing client after remote shutdown by calling `caif_disconnect_client()` followed by `caif_free_client()`. `caif_free_client()` releases the service layer referenced by `adap_layer->dn`, but leaves that pointer stale. When the socket is later destroyed, `caif_sock_destructor()` calls `caif_free_client()` again and dereferences the freed service pointer. Clear the client/service links before releasing the service object so repeated teardown becomes harmless.

References 8

• git.kernel.org https://git.kernel.org/stable/c/3ac6db584d9d420267bb8413115707eeec76d9cf
• git.kernel.org https://git.kernel.org/stable/c/63d21a3aa0108b9dde4e99b0d3d5d679ac68c0f9
• git.kernel.org https://git.kernel.org/stable/c/7ef97d4675b05a103648bd9244d91dff7d8c08b0
• git.kernel.org https://git.kernel.org/stable/c/914c6456fcfc21a3d553945dff62fd1621d6155d
• git.kernel.org https://git.kernel.org/stable/c/a4b191ddc12c55ddb62feb096536f819f384d6f1
• git.kernel.org https://git.kernel.org/stable/c/cffca7a18b8f9de7c3d3013a1f5740c412b2a501
• git.kernel.org https://git.kernel.org/stable/c/e16859f3f4426fa349bc5519d582a93d28f5a15d
• git.kernel.org https://git.kernel.org/stable/c/f7cf8ece8cee3c1ee361991470cdb1eb65ab02e8

Remediation