diff options
Diffstat (limited to 'meta-openbmc-mods/meta-common/recipes-kernel/linux/linux-aspeed/CVE-2022-3623.patch')
| -rw-r--r-- | meta-openbmc-mods/meta-common/recipes-kernel/linux/linux-aspeed/CVE-2022-3623.patch | 175 |
1 files changed, 175 insertions, 0 deletions
diff --git a/meta-openbmc-mods/meta-common/recipes-kernel/linux/linux-aspeed/CVE-2022-3623.patch b/meta-openbmc-mods/meta-common/recipes-kernel/linux/linux-aspeed/CVE-2022-3623.patch new file mode 100644 index 000000000..d44f786de --- /dev/null +++ b/meta-openbmc-mods/meta-common/recipes-kernel/linux/linux-aspeed/CVE-2022-3623.patch @@ -0,0 +1,175 @@ +From fac35ba763ed07ba93154c95ffc0c4a55023707f Mon Sep 17 00:00:00 2001 +From: Baolin Wang <baolin.wang@linux.alibaba.com> +Date: Thu, 1 Sep 2022 18:41:31 +0800 +Subject: mm/hugetlb: fix races when looking up a CONT-PTE/PMD size hugetlb + page + +On some architectures (like ARM64), it can support CONT-PTE/PMD size +hugetlb, which means it can support not only PMD/PUD size hugetlb (2M and +1G), but also CONT-PTE/PMD size(64K and 32M) if a 4K page size specified. + +So when looking up a CONT-PTE size hugetlb page by follow_page(), it will +use pte_offset_map_lock() to get the pte entry lock for the CONT-PTE size +hugetlb in follow_page_pte(). However this pte entry lock is incorrect +for the CONT-PTE size hugetlb, since we should use huge_pte_lock() to get +the correct lock, which is mm->page_table_lock. + +That means the pte entry of the CONT-PTE size hugetlb under current pte +lock is unstable in follow_page_pte(), we can continue to migrate or +poison the pte entry of the CONT-PTE size hugetlb, which can cause some +potential race issues, even though they are under the 'pte lock'. + +For example, suppose thread A is trying to look up a CONT-PTE size hugetlb +page by move_pages() syscall under the lock, however antoher thread B can +migrate the CONT-PTE hugetlb page at the same time, which will cause +thread A to get an incorrect page, if thread A also wants to do page +migration, then data inconsistency error occurs. + +Moreover we have the same issue for CONT-PMD size hugetlb in +follow_huge_pmd(). + +To fix above issues, rename the follow_huge_pmd() as follow_huge_pmd_pte() +to handle PMD and PTE level size hugetlb, which uses huge_pte_lock() to +get the correct pte entry lock to make the pte entry stable. + +Mike said: + +Support for CONT_PMD/_PTE was added with bb9dd3df8ee9 ("arm64: hugetlb: +refactor find_num_contig()"). Patch series "Support for contiguous pte +hugepages", v4. However, I do not believe these code paths were +executed until migration support was added with 5480280d3f2d ("arm64/mm: +enable HugeTLB migration for contiguous bit HugeTLB pages") I would go +with 5480280d3f2d for the Fixes: targe. + +Link: https://lkml.kernel.org/r/635f43bdd85ac2615a58405da82b4d33c6e5eb05.1662017562.git.baolin.wang@linux.alibaba.com +Fixes: 5480280d3f2d ("arm64/mm: enable HugeTLB migration for contiguous bit HugeTLB pages") +Signed-off-by: Baolin Wang <baolin.wang@linux.alibaba.com> +Suggested-by: Mike Kravetz <mike.kravetz@oracle.com> +Reviewed-by: Mike Kravetz <mike.kravetz@oracle.com> +Cc: David Hildenbrand <david@redhat.com> +Cc: Muchun Song <songmuchun@bytedance.com> +Cc: <stable@vger.kernel.org> +Signed-off-by: Andrew Morton <akpm@linux-foundation.org> +--- + include/linux/hugetlb.h | 8 ++++---- + mm/gup.c | 14 +++++++++++++- + mm/hugetlb.c | 27 +++++++++++++-------------- + 3 files changed, 30 insertions(+), 19 deletions(-) + +diff --git a/include/linux/hugetlb.h b/include/linux/hugetlb.h +index 3ec981a0d8b3a..67c88b82fc32d 100644 +--- a/include/linux/hugetlb.h ++++ b/include/linux/hugetlb.h +@@ -207,8 +207,8 @@ struct page *follow_huge_addr(struct mm_struct *mm, unsigned long address, + struct page *follow_huge_pd(struct vm_area_struct *vma, + unsigned long address, hugepd_t hpd, + int flags, int pdshift); +-struct page *follow_huge_pmd(struct mm_struct *mm, unsigned long address, +- pmd_t *pmd, int flags); ++struct page *follow_huge_pmd_pte(struct vm_area_struct *vma, unsigned long address, ++ int flags); + struct page *follow_huge_pud(struct mm_struct *mm, unsigned long address, + pud_t *pud, int flags); + struct page *follow_huge_pgd(struct mm_struct *mm, unsigned long address, +@@ -312,8 +312,8 @@ static inline struct page *follow_huge_pd(struct vm_area_struct *vma, + return NULL; + } + +-static inline struct page *follow_huge_pmd(struct mm_struct *mm, +- unsigned long address, pmd_t *pmd, int flags) ++static inline struct page *follow_huge_pmd_pte(struct vm_area_struct *vma, ++ unsigned long address, int flags) + { + return NULL; + } +diff --git a/mm/gup.c b/mm/gup.c +index 00926abb44263..251cb6a10bc0d 100644 +--- a/mm/gup.c ++++ b/mm/gup.c +@@ -530,6 +530,18 @@ static struct page *follow_page_pte(struct vm_area_struct *vma, + if (WARN_ON_ONCE((flags & (FOLL_PIN | FOLL_GET)) == + (FOLL_PIN | FOLL_GET))) + return ERR_PTR(-EINVAL); ++ ++ /* ++ * Considering PTE level hugetlb, like continuous-PTE hugetlb on ++ * ARM64 architecture. ++ */ ++ if (is_vm_hugetlb_page(vma)) { ++ page = follow_huge_pmd_pte(vma, address, flags); ++ if (page) ++ return page; ++ return no_page_table(vma, flags); ++ } ++ + retry: + if (unlikely(pmd_bad(*pmd))) + return no_page_table(vma, flags); +@@ -662,7 +674,7 @@ static struct page *follow_pmd_mask(struct vm_area_struct *vma, + if (pmd_none(pmdval)) + return no_page_table(vma, flags); + if (pmd_huge(pmdval) && is_vm_hugetlb_page(vma)) { +- page = follow_huge_pmd(mm, address, pmd, flags); ++ page = follow_huge_pmd_pte(vma, address, flags); + if (page) + return page; + return no_page_table(vma, flags); +diff --git a/mm/hugetlb.c b/mm/hugetlb.c +index 0bdfc7e1c933f..9564bf817e6a8 100644 +--- a/mm/hugetlb.c ++++ b/mm/hugetlb.c +@@ -6946,12 +6946,13 @@ follow_huge_pd(struct vm_area_struct *vma, + } + + struct page * __weak +-follow_huge_pmd(struct mm_struct *mm, unsigned long address, +- pmd_t *pmd, int flags) ++follow_huge_pmd_pte(struct vm_area_struct *vma, unsigned long address, int flags) + { ++ struct hstate *h = hstate_vma(vma); ++ struct mm_struct *mm = vma->vm_mm; + struct page *page = NULL; + spinlock_t *ptl; +- pte_t pte; ++ pte_t *ptep, pte; + + /* FOLL_GET and FOLL_PIN are mutually exclusive. */ + if (WARN_ON_ONCE((flags & (FOLL_PIN | FOLL_GET)) == +@@ -6961,17 +6962,15 @@ follow_huge_pmd(struct mm_struct *mm, unsigned long address, + return NULL; + + retry: +- ptl = pmd_lockptr(mm, pmd); +- spin_lock(ptl); +- /* +- * make sure that the address range covered by this pmd is not +- * unmapped from other threads. +- */ +- if (!pmd_huge(*pmd)) +- goto out; +- pte = huge_ptep_get((pte_t *)pmd); ++ ptep = huge_pte_offset(mm, address, huge_page_size(h)); ++ if (!ptep) ++ return NULL; ++ ++ ptl = huge_pte_lock(h, mm, ptep); ++ pte = huge_ptep_get(ptep); + if (pte_present(pte)) { +- page = pmd_page(*pmd) + ((address & ~PMD_MASK) >> PAGE_SHIFT); ++ page = pte_page(pte) + ++ ((address & ~huge_page_mask(h)) >> PAGE_SHIFT); + /* + * try_grab_page() should always succeed here, because: a) we + * hold the pmd (ptl) lock, and b) we've just checked that the +@@ -6987,7 +6986,7 @@ retry: + } else { + if (is_hugetlb_entry_migration(pte)) { + spin_unlock(ptl); +- __migration_entry_wait(mm, (pte_t *)pmd, ptl); ++ __migration_entry_wait_huge(ptep, ptl); + goto retry; + } + /* +-- +cgit + |