thunderbolt: Reject oversized XDomain properties responses

Overview

In the Linux kernel, the following vulnerability has been resolved:

thunderbolt: Reject oversized XDomain properties responses

tb_xdp_properties_request() allocates room for 45 data dwords in its 252-byte response buffer. The XDomain length field is six bits wide, however, and a malicious peer can set it to 63. After the fixed response fields are subtracted, the driver treats this as 48 data dwords.

Commit 322e93448d90 ("thunderbolt: Clamp XDomain response data copy to allocation size") only bounds the copy against data_len. If data_len is at least 48, memcpy() reads 192 bytes from the 180-byte res->data array, causing a 12-byte heap out-of-bounds read. Commit 4db2bd2ed478 ("thunderbolt: Limit XDomain response copy to actual frame size") limits the earlier copy but does not constrain this header-derived length.

Reject response data lengths that exceed the allocated source buffer before copying them into the assembled property block.

Affected

• Linux >= d1ff70241a275133e1a0258b7c23588b122276c8 < b270c1074860de74da0d6b5250fb06b359b9d509
• Linux >= d1ff70241a275133e1a0258b7c23588b122276c8 < a766a86ff48acee76aeb8e2575771040749e509d
• Linux >= d1ff70241a275133e1a0258b7c23588b122276c8 < 2f97f929dad9eb3e1f63b721d2dd49bf9bc68efa
• Linux >= d1ff70241a275133e1a0258b7c23588b122276c8 < 737a1d2e9642d5f718bd29aa4a98b9eef3832f0a
• Linux >= d1ff70241a275133e1a0258b7c23588b122276c8 < 80756e263846ab694984e749e8c626897331438f
• Linux 4.15

Remediation

Refer to the linked advisories for vendor-supplied fixes and affected version ranges.