Description
In the Linux kernel, the following vulnerability has been resolved: mm/damon/vaddr: do not repeat pte_offset_map_lock() until success DAMON's virtual address space operation set implementation (vaddr) calls pte_offset_map_lock() inside the page table walk callback function. This is for reading and writing page table accessed bits. If pte_offset_map_lock() fails, it retries by returning the page table walk callback function with ACTION_AGAIN. pte_offset_map_lock() can continuously fail if the target is a pmd migration entry, though. Hence it could cause an infinite page table walk if the migration cannot be done until the page table walk is finished. This indeed caused a soft lockup when CPU hotplugging and DAMON were running in parallel. Avoid the infinite loop by simply not retrying the page table walk. DAMON is promising only a best-effort accuracy, so missing access to such pages is no problem.
Affected products
Version statuses are supplied by the assigning organization. Consult the original record for detailed ranges and platform conditions.
Linux Linux
Default version status: unaffected
7780d04046a2288ab85d88bedacc60fa4fad9971 to < 677ebfe5d00f94adec0c0204f6e6e2a82d3f77bfaffected7780d04046a2288ab85d88bedacc60fa4fad9971 to < ac42320ec873bfe726141069cfdd90ee5bc4e885affected7780d04046a2288ab85d88bedacc60fa4fad9971 to < 0ccd91cf749536d41307a07e60ec14ab0dbf21f5affected7780d04046a2288ab85d88bedacc60fa4fad9971 to < b93af2cc8e036754c0d9970d9ddc47f43cc94b9faffected
Linux Linux
Default version status: affected
6.5affected0 to < 6.5unaffected6.6.113 to ≤ 6.6.*unaffected6.12.54 to ≤ 6.12.*unaffected6.17.4 to ≤ 6.17.*unaffected6.18 to ≤ *unaffected