CVE-2024-50227

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

thunderbolt: Fix KASAN reported stack out-of-bounds read in tbretimerscan()

KASAN reported following issue:

BUG: KASAN: stack-out-of-bounds in tbretimerscan+0xffe/0x1550 [thunderbolt] Read of size 4 at addr ffff88810111fc1c by task kworker/u56:0/11 CPU: 0 UID: 0 PID: 11 Comm: kworker/u56:0 Tainted: G U 6.11.0+ #1387 Tainted: [U]=USER Workqueue: thunderbolt0 tbhandlehotplug [thunderbolt] Call Trace: <TASK> dumpstacklvl+0x6c/0x90 printreport+0xd1/0x630 kasanreport+0xdb/0x110 _asanreportload4noabort+0x14/0x20 tbretimerscan+0xffe/0x1550 [thunderbolt] tbscanport+0xa6f/0x2060 [thunderbolt] tbhandlehotplug+0x17b1/0x3080 [thunderbolt] processonework+0x626/0x1100 workerthread+0x6c8/0xfa0 kthread+0x2c8/0x3a0 retfromfork+0x3a/0x80 retfromforkasm+0x1a/0x30

This happens because the loop variable still gets incremented by one so max becomes 3 instead of 2, and this makes the second loop read past the the array declared on the stack.

Fix this by assigning to max directly in the loop body.