[PATCH v4 0/2] fix the missing underflow in memory operation function

[Walter Wu <walter-zh.wu@mediatek.com>]

The patchsets help to produce KASAN report when size is negative numbers
in memory operation function. It is helpful for programmer to solve the 
undefined behavior issue. Patch 1 based on Dmitry's review and
suggestion, patch 2 is a test in order to verify the patch 1. 

[1]https://bugzilla.kernel.org/show_bug.cgi?id=199341 
[2]https://lore.kernel.org/linux-arm-kernel/20190927034338.15813-1-walter-zh.wu@mediatek.com/ 

Walter Wu (2): 
kasan: detect negative size in memory operation function 
kasan: add test for invalid size in memmove
---
Changes in v2:
fix the indentation, thanks for the reminder Matthew.

Changes in v3:
Add a confition for memory operation function, need to
avoid the false alarm when KASAN un-initialized.

Changes in v4:
modify negative size condition
modify comments
modify the fixed code about early stages of boot
---
 include/linux/kasan.h     |  2 +-
 lib/test_kasan.c          | 18 ------------------
 mm/kasan/common.c         | 25 +++++++------------------
 mm/kasan/generic.c        |  9 ++++-----
 mm/kasan/generic_report.c | 11 -----------
 mm/kasan/kasan.h          |  2 +-
 mm/kasan/report.c         |  5 ++++-
 mm/kasan/tags.c           |  9 ++++-----
 mm/kasan/tags_report.c    | 11 -----------
 9 files changed, 21 insertions(+), 71 deletions(-)

-- 
2.18.0