lkml.org 
[lkml]   [2022]   [Jun]   [28]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
/
From
Subject[PATCH v2 0/1] mm: kfence: fix unexpected leak scan on kfence pool
Date
From: Yee Lee <yee.lee@mediatek.com>

Since the latest patches of kmemleak separated its address management
to two rb-trees, phys and virt, the kmemleak_free failed to free kfence_pool
from the virt tree. It caused unexpected scan the blocks and triggered
kfence faults.

Reference:
https://lore.kernel.org/linux-mm/20220611035551.1823303-1-patrick.wang.shcn@gmail.com/

==================================================================
BUG: KFENCE: invalid read in scan_block+0x13c/0x838

Invalid read at 0x000000003dc26873:
scan_block+0x13c/0x838
scan_gray_list+0x1f0/0x478
kmemleak_scan+0x63c/0xd64
kmemleak_write+0x618/0x8cc
full_proxy_write+0x70/0x138
vfs_write+0x108/0x314
ksys_write+0x7c/0x14c
__arm64_sys_write+0x20/0x30
el0_svc_common+0xa8/0x144
do_el0_svc+0x30/0xd4
el0_svc+0x38/0x15c
el0t_64_sync_handler+0x88/0xf8
el0t_64_sync+0x1a0/0x1a4

CPU: 0 PID: 128 Comm: sh Not tainted 5.18.0-mainline-40996-g7d83a175ff4a-dirty #1
Hardware name: linux,dummy-virt (DT)
==================================================================

This patch applies kmemleak_ignore_phys() to replace the original kmemleak_free and
adapts it to the late enabling case.

v1->v2:
- use kmemleak_ignore_phys() to bypass the scanning.
- move out the freeing opeartion from late enabling as it's trivial.

Yee Lee (1):
mm: kfence: apply kmemleak_ignore_phys on early allocated pool

mm/kfence/core.c | 18 +++++++++---------
1 file changed, 9 insertions(+), 9 deletions(-)

--
2.18.0

\
 
 \ /
  Last update: 2022-06-28 13:39    [W:0.809 / U:0.280 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site