linux/mm/damon
SeongJae Park 1de09a7281 mm/damon/dbgfs: check if rm_contexts input is for a real context
A user could write a name of a file under 'damon/' debugfs directory,
which is not a user-created context, to 'rm_contexts' file.  In the case,
'dbgfs_rm_context()' just assumes it's the valid DAMON context directory
only if a file of the name exist.  As a result, invalid memory access
could happen as below.  Fix the bug by checking if the given input is for
a directory.  This check can filter out non-context inputs because
directories under 'damon/' debugfs directory can be created via only
'mk_contexts' file.

This bug has found by syzbot[1].

[1] https://lore.kernel.org/damon/000000000000ede3ac05ec4abf8e@google.com/

Link: https://lkml.kernel.org/r/20221107165001.5717-2-sj@kernel.org
Fixes: 75c1c2b53c ("mm/damon/dbgfs: support multiple contexts")
Signed-off-by: SeongJae Park <sj@kernel.org>
Reported-by: syzbot+6087eafb76a94c4ac9eb@syzkaller.appspotmail.com
Cc: <stable@vger.kernel.org>	[5.15.x]
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2022-11-08 15:57:25 -08:00
..
core-test.h mm/damon/core-test: test damon_set_regions 2022-10-03 14:03:06 -07:00
core.c - Alistair Popple has a series which addresses a race which causes page 2022-10-14 12:28:43 -07:00
dbgfs-test.h mm/damon/dbgfs-test: fix is_target_id() change 2022-03-22 15:57:12 -07:00
dbgfs.c mm/damon/dbgfs: check if rm_contexts input is for a real context 2022-11-08 15:57:25 -08:00
Kconfig mm/damon/Kconfig: notify debugfs deprecation plan 2022-10-03 14:03:06 -07:00
lru_sort.c mm/damon: deduplicate damon_{reclaim,lru_sort}_apply_parameters() 2022-10-03 14:03:31 -07:00
Makefile mm/damon: introduce DAMON-based LRU-lists Sorting 2022-07-03 18:08:43 -07:00
modules-common.h mm/damon/modules-common: implement damos time quota params generator 2022-10-03 14:03:13 -07:00
ops-common.c mm/damon: rename damon_pageout_score() to damon_cold_score() 2022-10-03 14:03:31 -07:00
ops-common.h mm/damon: rename damon_pageout_score() to damon_cold_score() 2022-10-03 14:03:31 -07:00
paddr.c mm/damon: rename damon_pageout_score() to damon_cold_score() 2022-10-03 14:03:31 -07:00
reclaim.c mm/damon: deduplicate damon_{reclaim,lru_sort}_apply_parameters() 2022-10-03 14:03:31 -07:00
sysfs.c - Yu Zhao's Multi-Gen LRU patches are here. They've been under test in 2022-10-10 17:53:04 -07:00
vaddr-test.h damon: convert __damon_va_three_regions to use the VMA iterator 2022-09-26 19:46:16 -07:00
vaddr.c mm/damon: use damon_sz_region() in appropriate place 2022-10-12 18:51:49 -07:00