Clamp XDomain response data copy to allocation size

Summary

In the Linux kernel, the following vulnerability has been resolved: thunderbolt: Clamp XDomain response data copy to allocation size tb_xdp_properties_request() derives the per-packet copy length from the response header without checking that it fits in the previously allocated data buffer. A malicious peer can set its length field larger than the declared data_length, causing memcpy to write past the kcalloc allocation. Clamp the per-packet copy length so that the cumulative offset never exceeds data_len. A flaw was found in the Linux kernel's Thunderbolt driver. A malicious peer can exploit this vulnerability by sending a specially crafted response that causes the system to write data beyond an allocated memory buffer. This out-of-bounds write can lead to memory corruption, which may allow an attacker to cause a denial of service or potentially execute arbitrary code. Red Hat severity: Important — CVSS 7 (CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:U/C:H/I:H/A:H). Weakness: CWE-787. No fixing RHSA erratum has published yet; monitor the Red Hat CVE page and patch when it ships.