Re: [PATCH v1 0/8] Fix set_huge_pte_at() panic on arm64
From: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Date: 2023-09-22 09:23:19
Also in:
linux-arm-kernel, linux-mm, linux-riscv, linux-s390, lkml, sparclinux, stable
On Thu, Sep 21, 2023 at 05:35:54PM +0100, Ryan Roberts wrote:
On 21/09/2023 17:30, Andrew Morton wrote:quoted
On Thu, 21 Sep 2023 17:19:59 +0100 Ryan Roberts [off-list ref] wrote:quoted
Hi All, This series fixes a bug in arm64's implementation of set_huge_pte_at(), which can result in an unprivileged user causing a kernel panic. The problem was triggered when running the new uffd poison mm selftest for HUGETLB memory. This test (and the uffd poison feature) was merged for v6.6-rc1. However, upon inspection there are multiple other pre-existing paths that can trigger this bug. Ideally, I'd like to get this fix in for v6.6 if possible? And I guess it should be backported too, given there are call sites where this can theoretically happen that pre-date v6.6-rc1 (I've cc'ed stable@vger.kernel.org).This gets you a naggygram from Greg. The way to request a backport is to add cc:stable to all the changelogs. I'll make that change to my copy.Ahh, sorry about that... I just got the same moan from the kernel test robot too.quoted
quoted
Ryan Roberts (8): parisc: hugetlb: Convert set_huge_pte_at() to take vma powerpc: hugetlb: Convert set_huge_pte_at() to take vma riscv: hugetlb: Convert set_huge_pte_at() to take vma s390: hugetlb: Convert set_huge_pte_at() to take vma sparc: hugetlb: Convert set_huge_pte_at() to take vma mm: hugetlb: Convert set_huge_pte_at() to take vma arm64: hugetlb: Convert set_huge_pte_at() to take vma arm64: hugetlb: Fix set_huge_pte_at() to work with all swap entries arch/arm64/include/asm/hugetlb.h | 2 +- arch/arm64/mm/hugetlbpage.c | 22 ++++---------- arch/parisc/include/asm/hugetlb.h | 2 +- arch/parisc/mm/hugetlbpage.c | 4 +-- .../include/asm/nohash/32/hugetlb-8xx.h | 3 +- arch/powerpc/mm/book3s64/hugetlbpage.c | 2 +- arch/powerpc/mm/book3s64/radix_hugetlbpage.c | 2 +- arch/powerpc/mm/nohash/8xx.c | 2 +- arch/powerpc/mm/pgtable.c | 7 ++++- arch/riscv/include/asm/hugetlb.h | 2 +- arch/riscv/mm/hugetlbpage.c | 3 +- arch/s390/include/asm/hugetlb.h | 8 +++-- arch/s390/mm/hugetlbpage.c | 8 ++++- arch/sparc/include/asm/hugetlb.h | 8 +++-- arch/sparc/mm/hugetlbpage.c | 8 ++++- include/asm-generic/hugetlb.h | 6 ++-- include/linux/hugetlb.h | 6 ++-- mm/damon/vaddr.c | 2 +- mm/hugetlb.c | 30 +++++++++---------- mm/migrate.c | 2 +- mm/rmap.c | 10 +++---- mm/vmalloc.c | 5 +++- 22 files changed, 80 insertions(+), 64 deletions(-)Looks scary but it's actually a fairly modest patchset. It could easily be all rolled into a single patch for ease of backporting. Maybe Greg has an opinion?Yes, I thought about doing that; or perhaps 2 patches - one for the interface change across all arches and core code, and one for the actual bug fix?
I have no issues with taking patch series, or one big patch, into stable trees, they just have to match up with what is in Linus's tree. so if it makes more sense to have this as a series (like you did here), wonderful, make it a patch series. Do not go out of your way to do things differently just for stable kernels, that is not necessary or needed at all. thanks, greg k-h