linux-kernel - Re: [PATCH v2 0/2] mm/damon: fixes for address alignment issues in DAMON_LRU_SORT and DAMON

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Message-ID: <20251020150625.34941-1-sj@kernel.org>
Date: Mon, 20 Oct 2025 08:06:25 -0700
From: SeongJae Park <sj@...nel.org>
To: Quanmin Yan <yanquanmin1@...wei.com>
Cc: SeongJae Park <sj@...nel.org>,
	akpm@...ux-foundation.org,
	damon@...ts.linux.dev,
	linux-kernel@...r.kernel.org,
	linux-mm@...ck.org,
	wangkefeng.wang@...wei.com,
	zuoze1@...wei.com
Subject: Re: [PATCH v2 0/2] mm/damon: fixes for address alignment issues in DAMON_LRU_SORT and DAMON_RECLAIM

On Mon, 20 Oct 2025 21:01:23 +0800 Quanmin Yan <yanquanmin1@...wei.com> wrote:

> In DAMON_LRU_SORT and DAMON_RECLAIM, damon_set_regions() will apply
> DAMON_MIN_REGION as the core address alignment, and the monitoring
> target address ranges would be aligned on DAMON_MIN_REGION * addr_unit.
> When users 1) set addr_unit to a value larger than 1, and 2) set the
> monitoring target address range as not aligned on DAMON_MIN_REGION *
> addr_unit, it will cause DAMON_LRU_SORT and DAMON_RECLAIM to operate
> on unexpectedly large physical address ranges.
> 
> For example, if the user sets the monitoring target address range to
> [4, 8) and addr_unit as 1024, the aimed monitoring target address range
> is [4 KiB, 8 KiB). Assuming DAMON_MIN_REGION is 4096, so resulting
> target address range will be [0, 4096) in the DAMON core layer address
> system, and [0, 4 MiB) in the physical address space, which is an
> unexpected range.
> 
> To fix the issue, add a min_sz_region parameter to
> damon_set_region_biggest_system_ram_default() and use it when calling
> damon_set_regions(), replacing the direct use of DAMON_MIN_REGION.
> 
> Changes from v1
> (https://lore.kernel.org/all/20251016104717.2194909-1-yanquanmin1@huawei.com/)
> - Added more issue description in the commit message.
> - Split the original fix patch into two separate patches.

Thank you for nicely revising this!


Thanks,
SJ

[...]