[v3,0/3] Fix undefined behaviour during device synchronization

Message

Li Jinlin Dec. 10, 2021, 12:06 p.m. UTC

md/drbd drivers use 'signed int' variable to track sync vs non-sync IO,
and judge whether sync IO needs to be throttled by signed comparison.
If the value of the variable is greater than INT_MAX or close to
INT_MAX, some undefined behavior may occur.

Fix by using 64bit signed integer type.

differences to v2:
- Don't move sync_io variable form struct gendisk to struct md_rdev
  in these patch
- fix typo in suject

The v2 "md: Fix undefined behaviour in is_mddev_idle" patch
differences to v1:
- add ubsan info in message
- use 64bit signed integer type instead of long type;
- move sync_io variable form struct gendisk to struct md_rdev, and 
  modify md_sync_acct() and md_sync_acct_bio() to fit for this change.

Li Jinlin (3):
  md: Fix undefined behaviour in is_mddev_idle
  drbd: Fix undefined behaviour in drbd_rs_c_min_rate_throttle
  drbd: Remove useless variable in struct drbd_device

 drivers/block/drbd/drbd_bitmap.c   |  2 +-
 drivers/block/drbd/drbd_int.h      |  5 ++---
 drivers/block/drbd/drbd_main.c     |  3 +--
 drivers/block/drbd/drbd_receiver.c | 12 ++++++------
 drivers/block/drbd/drbd_state.c    |  1 -
 drivers/block/drbd/drbd_worker.c   |  5 ++---
 drivers/md/md.c                    |  6 +++---
 drivers/md/md.h                    |  4 ++--
 include/linux/genhd.h              |  2 +-
 9 files changed, 18 insertions(+), 22 deletions(-)