[SRU Focal 0/2] CVE-2021-4002

[Thadeu Lima de Souza Cascardo]

https://www.openwall.com/lists/oss-security/2021/11/25/1

[Impact]
Missing TLB flush on hugetlb unmapping may allow a different process to
access another process memory, as long as it is using hugetlb mappings.

[Test case]
POC from the link above was used to test it on amd64 and ppc64el (Power9).

Built tested on other architectures too. Will test on them as time allows.

[Potential regression]
hugetlb users may regress.

[Notice]
4.15 backport is in progress and will be tested on other architectures
as well.


Nadav Amit (1):
  hugetlbfs: flush TLBs correctly after huge_pmd_unshare

Peter Zijlstra (Intel) (1):
  tlb: mmu_gather: add tlb_flush_*_range APIs

 include/asm-generic/tlb.h | 55 ++++++++++++++++++++++++++++-----------
 mm/hugetlb.c              | 23 +++++++++++++---
 2 files changed, 59 insertions(+), 19 deletions(-)

-- 
2.32.0