On Thu, 21 Sep 2023 17:19:59 +0100 Ryan Roberts <ryan.roberts@xxxxxxx> wrote: > 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@xxxxxxxxxxxxxxx). 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. > 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?