SeongJae Park 4401e9d10a mm/damon/core: avoid overflow in damon_feed_loop_next_input() ... damon_feed_loop_next_input() is inefficient and fragile to overflows. Specifically, 'score_goal_diff_bp' calculation can overflow when 'score' is high. The calculation is actually unnecessary at all because 'goal' is a constant of value 10,000. Calculation of 'compensation' is again fragile to overflow. Final calculation of return value for under-achiving case is again fragile to overflow when the current score is under-achieving the target. Add two corner cases handling at the beginning of the function to make the body easier to read, and rewrite the body of the function to avoid overflows and the unnecessary bp value calcuation. Link: https://lkml.kernel.org/r/20241031161203.47751-1-sj@kernel.org Fixes: 9294a037c0 ("mm/damon/core: implement goal-oriented feedback-driven quota auto-tuning") Signed-off-by: SeongJae Park <sj@kernel.org> Reported-by: Guenter Roeck <linux@roeck-us.net> Closes: https://lore.kernel.org/944f3d5b-9177-48e7-8ec9-7f1331a3fea3@roeck-us.net Tested-by: Guenter Roeck <linux@roeck-us.net> Cc: <stable@vger.kernel.org> [6.8.x] Signed-off-by: Andrew Morton <akpm@linux-foundation.org>		2024-11-07 14:14:59 -08:00
..
tests	mm/damon/tests/sysfs-kunit.h: fix memory leak in damon_sysfs_test_add_targets()	2024-10-17 00:28:08 -07:00
core.c	mm/damon/core: avoid overflow in damon_feed_loop_next_input()	2024-11-07 14:14:59 -08:00
dbgfs.c	mm/damon: move kunit tests to tests/ subdirectory with _kunit suffix	2024-09-03 21:15:58 -07:00
Kconfig	mm/damon/Kconfig: update DAMON doc URL	2024-09-26 14:01:44 -07:00
lru_sort.c	Revert "mm/damon/lru_sort: adjust local variable to dynamic allocation"	2024-09-09 16:39:00 -07:00
Makefile
modules-common.c	mm/damon: update email of SeongJae	2023-12-20 14:48:13 -08:00
modules-common.h
ops-common.c	mm/damon/ops-common: avoid divide-by-zero during region hotness calculation	2023-10-25 16:47:15 -07:00
ops-common.h
paddr.c	mm/damon/paddr: initialize nr_succeeded in __damon_pa_migrate_folio_list()	2024-07-04 18:05:50 -07:00
reclaim.c	mm/damon/reclaim: remove unnecessary code for online tuning	2024-07-03 19:30:14 -07:00
sysfs-common.c
sysfs-common.h	mm/damon/sysfs-schemes: rename *_set_{schemes,scheme_filters,quota_score,schemes}()	2024-07-03 19:30:14 -07:00
sysfs-schemes.c	mm/damon/sysfs-schemes: rename *_set_{schemes,scheme_filters,quota_score,schemes}()	2024-07-03 19:30:14 -07:00
sysfs.c	mm/damon: move kunit tests to tests/ subdirectory with _kunit suffix	2024-09-03 21:15:58 -07:00
vaddr.c	ALong with the usual shower of singleton patches, notable patch series in	2024-09-21 07:29:05 -07:00