November 2018 - Linux-stable-mirror

FAILED: patch "[PATCH] mm: migration: fix migration of huge PMD shared pages" failed to apply to 4.4-stable tree

by gregkh＠linuxfoundation.org

The patch below does not apply to the 4.4-stable tree. If someone wants it applied there, or to any other stable or longterm tree, then please email the backport, including the original git commit id to <stable(a)vger.kernel.org>. thanks, greg k-h ------------------ original commit in Linus's tree ------------------ >From 017b1660df89f5fb4bfe66c34e35f7d2031100c7 Mon Sep 17 00:00:00 2001 From: Mike Kravetz <mike.kravetz(a)oracle.com> Date: Fri, 5 Oct 2018 15:51:29 -0700 Subject: [PATCH] mm: migration: fix migration of huge PMD shared pages The page migration code employs try_to_unmap() to try and unmap the source page. This is accomplished by using rmap_walk to find all vmas where the page is mapped. This search stops when page mapcount is zero. For shared PMD huge pages, the page map count is always 1 no matter the number of mappings. Shared mappings are tracked via the reference count of the PMD page. Therefore, try_to_unmap stops prematurely and does not completely unmap all mappings of the source page. This problem can result is data corruption as writes to the original source page can happen after contents of the page are copied to the target page. Hence, data is lost. This problem was originally seen as DB corruption of shared global areas after a huge page was soft offlined due to ECC memory errors. DB developers noticed they could reproduce the issue by (hotplug) offlining memory used to back huge pages. A simple testcase can reproduce the problem by creating a shared PMD mapping (note that this must be at least PUD_SIZE in size and PUD_SIZE aligned (1GB on x86)), and using migrate_pages() to migrate process pages between nodes while continually writing to the huge pages being migrated. To fix, have the try_to_unmap_one routine check for huge PMD sharing by calling huge_pmd_unshare for hugetlbfs huge pages. If it is a shared mapping it will be 'unshared' which removes the page table entry and drops the reference on the PMD page. After this, flush caches and TLB. mmu notifiers are called before locking page tables, but we can not be sure of PMD sharing until page tables are locked. Therefore, check for the possibility of PMD sharing before locking so that notifiers can prepare for the worst possible case. Link: http://lkml.kernel.org/r/20180823205917.16297-2-mike.kravetz@oracle.com [mike.kravetz(a)oracle.com: make _range_in_vma() a static inline] Link: http://lkml.kernel.org/r/6063f215-a5c8-2f0c-465a-2c515ddc952d@oracle.com Fixes: 39dde65c9940 ("shared page table for hugetlb page") Signed-off-by: Mike Kravetz <mike.kravetz(a)oracle.com> Acked-by: Kirill A. Shutemov <kirill.shutemov(a)linux.intel.com> Reviewed-by: Naoya Horiguchi <n-horiguchi(a)ah.jp.nec.com> Acked-by: Michal Hocko <mhocko(a)suse.com> Cc: Vlastimil Babka <vbabka(a)suse.cz> Cc: Davidlohr Bueso <dave(a)stgolabs.net> Cc: Jerome Glisse <jglisse(a)redhat.com> Cc: Mike Kravetz <mike.kravetz(a)oracle.com> Cc: <stable(a)vger.kernel.org> Signed-off-by: Andrew Morton <akpm(a)linux-foundation.org> Signed-off-by: Greg Kroah-Hartman <gregkh(a)linuxfoundation.org> diff --git a/include/linux/hugetlb.h b/include/linux/hugetlb.h index 6b68e345f0ca..087fd5f48c91 100644 --- a/include/linux/hugetlb.h +++ b/include/linux/hugetlb.h @@ -140,6 +140,8 @@ pte_t *huge_pte_alloc(struct mm_struct *mm, pte_t *huge_pte_offset(struct mm_struct *mm, unsigned long addr, unsigned long sz); int huge_pmd_unshare(struct mm_struct *mm, unsigned long *addr, pte_t *ptep); +void adjust_range_if_pmd_sharing_possible(struct vm_area_struct *vma, + unsigned long *start, unsigned long *end); struct page *follow_huge_addr(struct mm_struct *mm, unsigned long address, int write); struct page *follow_huge_pd(struct vm_area_struct *vma, @@ -170,6 +172,18 @@ static inline unsigned long hugetlb_total_pages(void) return 0; } +static inline int huge_pmd_unshare(struct mm_struct *mm, unsigned long *addr, + pte_t *ptep) +{ + return 0; +} + +static inline void adjust_range_if_pmd_sharing_possible( + struct vm_area_struct *vma, + unsigned long *start, unsigned long *end) +{ +} + #define follow_hugetlb_page(m,v,p,vs,a,b,i,w,n) ({ BUG(); 0; }) #define follow_huge_addr(mm, addr, write) ERR_PTR(-EINVAL) #define copy_hugetlb_page_range(src, dst, vma) ({ BUG(); 0; }) diff --git a/include/linux/mm.h b/include/linux/mm.h index a61ebe8ad4ca..0416a7204be3 100644 --- a/include/linux/mm.h +++ b/include/linux/mm.h @@ -2455,6 +2455,12 @@ static inline struct vm_area_struct *find_exact_vma(struct mm_struct *mm, return vma; } +static inline bool range_in_vma(struct vm_area_struct *vma, + unsigned long start, unsigned long end) +{ + return (vma && vma->vm_start <= start && end <= vma->vm_end); +} + #ifdef CONFIG_MMU pgprot_t vm_get_page_prot(unsigned long vm_flags); void vma_set_page_prot(struct vm_area_struct *vma); diff --git a/mm/hugetlb.c b/mm/hugetlb.c index 3c21775f196b..b903d746e132 100644 --- a/mm/hugetlb.c +++ b/mm/hugetlb.c @@ -4545,12 +4545,40 @@ static bool vma_shareable(struct vm_area_struct *vma, unsigned long addr) /* * check on proper vm_flags and page table alignment */ - if (vma->vm_flags & VM_MAYSHARE && - vma->vm_start <= base && end <= vma->vm_end) + if (vma->vm_flags & VM_MAYSHARE && range_in_vma(vma, base, end)) return true; return false; } +/* + * Determine if start,end range within vma could be mapped by shared pmd. + * If yes, adjust start and end to cover range associated with possible + * shared pmd mappings. + */ +void adjust_range_if_pmd_sharing_possible(struct vm_area_struct *vma, + unsigned long *start, unsigned long *end) +{ + unsigned long check_addr = *start; + + if (!(vma->vm_flags & VM_MAYSHARE)) + return; + + for (check_addr = *start; check_addr < *end; check_addr += PUD_SIZE) { + unsigned long a_start = check_addr & PUD_MASK; + unsigned long a_end = a_start + PUD_SIZE; + + /* + * If sharing is possible, adjust start/end if necessary. + */ + if (range_in_vma(vma, a_start, a_end)) { + if (a_start < *start) + *start = a_start; + if (a_end > *end) + *end = a_end; + } + } +} + /* * Search for a shareable pmd page for hugetlb. In any case calls pmd_alloc() * and returns the corresponding pte. While this is not necessary for the @@ -4648,6 +4676,11 @@ int huge_pmd_unshare(struct mm_struct *mm, unsigned long *addr, pte_t *ptep) { return 0; } + +void adjust_range_if_pmd_sharing_possible(struct vm_area_struct *vma, + unsigned long *start, unsigned long *end) +{ +} #define want_pmd_share() (0) #endif /* CONFIG_ARCH_WANT_HUGE_PMD_SHARE */ diff --git a/mm/rmap.c b/mm/rmap.c index eb477809a5c0..1e79fac3186b 100644 --- a/mm/rmap.c +++ b/mm/rmap.c @@ -1362,11 +1362,21 @@ static bool try_to_unmap_one(struct page *page, struct vm_area_struct *vma, } /* - * We have to assume the worse case ie pmd for invalidation. Note that - * the page can not be free in this function as call of try_to_unmap() - * must hold a reference on the page. + * For THP, we have to assume the worse case ie pmd for invalidation. + * For hugetlb, it could be much worse if we need to do pud + * invalidation in the case of pmd sharing. + * + * Note that the page can not be free in this function as call of + * try_to_unmap() must hold a reference on the page. */ end = min(vma->vm_end, start + (PAGE_SIZE << compound_order(page))); + if (PageHuge(page)) { + /* + * If sharing is possible, start and end will be adjusted + * accordingly. + */ + adjust_range_if_pmd_sharing_possible(vma, &start, &end); + } mmu_notifier_invalidate_range_start(vma->vm_mm, start, end); while (page_vma_mapped_walk(&pvmw)) { @@ -1409,6 +1419,32 @@ static bool try_to_unmap_one(struct page *page, struct vm_area_struct *vma, subpage = page - page_to_pfn(page) + pte_pfn(*pvmw.pte); address = pvmw.address; + if (PageHuge(page)) { + if (huge_pmd_unshare(mm, &address, pvmw.pte)) { + /* + * huge_pmd_unshare unmapped an entire PMD + * page. There is no way of knowing exactly + * which PMDs may be cached for this mm, so + * we must flush them all. start/end were + * already adjusted above to cover this range. + */ + flush_cache_range(vma, start, end); + flush_tlb_range(vma, start, end); + mmu_notifier_invalidate_range(mm, start, end); + + /* + * The ref count of the PMD page was dropped + * which is part of the way map counting + * is done for shared PMDs. Return 'true' + * here. When there is no other sharing, + * huge_pmd_unshare returns false and we will + * unmap the actual page and drop map count + * to zero. + */ + page_vma_mapped_walk_done(&pvmw); + break; + } + } if (IS_ENABLED(CONFIG_MIGRATION) && (flags & TTU_MIGRATION) &&

5 years, 11 months

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[PATCH v8 08/17] tpm: call tpm2_flush_space() on error in tpm_try_transmit()

by Jarkko Sakkinen

Always call tpm2_flush_space() on failure in tpm_try_transmit() so that the volatile memory of the TPM gets cleared. If /dev/tpm0 does not have sufficient permissions (usually it has), this could lead to the leakage of TPM objects. Through /dev/tpmrm0 this issue does not raise any new security concerns. Cc: James Bottomley <James.Bottomley(a)HansenPartnership.com> Cc: stable(a)vger.kernel.org Fixes: 745b361e989a ("tpm:tpm: infrastructure for TPM spaces") Signed-off-by: Jarkko Sakkinen <jarkko.sakkinen(a)linux.intel.com> Reviewed-by: Stefan Berger <stefanb(a)linux.ibm.com> --- drivers/char/tpm/tpm-interface.c | 29 ++++++++++++----------------- drivers/char/tpm/tpm.h | 1 + drivers/char/tpm/tpm2-space.c | 2 +- 3 files changed, 14 insertions(+), 18 deletions(-) diff --git a/drivers/char/tpm/tpm-interface.c b/drivers/char/tpm/tpm-interface.c index 11af50646ed1..ef00b698ec02 100644 --- a/drivers/char/tpm/tpm-interface.c +++ b/drivers/char/tpm/tpm-interface.c @@ -224,14 +224,14 @@ static ssize_t tpm_try_transmit(struct tpm_chip *chip, rc = tpm2_prepare_space(chip, space, ordinal, buf); if (rc) - goto out; + goto out_idle; rc = chip->ops->send(chip, buf, count); if (rc < 0) { if (rc != -EPIPE) dev_err(&chip->dev, "%s: tpm_send: error %d\n", __func__, rc); - goto out; + goto out_space; } if (chip->flags & TPM_CHIP_FLAG_IRQ) @@ -247,7 +247,7 @@ static ssize_t tpm_try_transmit(struct tpm_chip *chip, if (chip->ops->req_canceled(chip, status)) { dev_err(&chip->dev, "Operation Canceled\n"); rc = -ECANCELED; - goto out; + goto out_space; } tpm_msleep(TPM_TIMEOUT_POLL); @@ -257,28 +257,23 @@ static ssize_t tpm_try_transmit(struct tpm_chip *chip, chip->ops->cancel(chip); dev_err(&chip->dev, "Operation Timed out\n"); rc = -ETIME; - goto out; + goto out_space; out_recv: len = chip->ops->recv(chip, buf, bufsiz); if (len < 0) { rc = len; - dev_err(&chip->dev, - "tpm_transmit: tpm_recv: error %d\n", rc); - goto out; - } else if (len < TPM_HEADER_SIZE) { + dev_err(&chip->dev, "tpm_transmit: tpm_recv: error %d\n", rc); + } else if (len < TPM_HEADER_SIZE || len != be32_to_cpu(header->length)) rc = -EFAULT; - goto out; - } - if (len != be32_to_cpu(header->length)) { - rc = -EFAULT; - goto out; - } - - rc = tpm2_commit_space(chip, space, ordinal, buf, &len); +out_space: + if (rc) + tpm2_flush_space(chip); + else + rc = tpm2_commit_space(chip, space, ordinal, buf, &len); -out: +out_idle: /* may fail but do not override previous error value in rc */ tpm_go_idle(chip, flags); diff --git a/drivers/char/tpm/tpm.h b/drivers/char/tpm/tpm.h index 86fa8ac0ae20..92638ec6ec97 100644 --- a/drivers/char/tpm/tpm.h +++ b/drivers/char/tpm/tpm.h @@ -576,6 +576,7 @@ int tpm2_probe(struct tpm_chip *chip); int tpm2_find_cc(struct tpm_chip *chip, u32 cc); int tpm2_init_space(struct tpm_space *space); void tpm2_del_space(struct tpm_chip *chip, struct tpm_space *space); +void tpm2_flush_space(struct tpm_chip *chip); int tpm2_prepare_space(struct tpm_chip *chip, struct tpm_space *space, u32 cc, u8 *cmd); int tpm2_commit_space(struct tpm_chip *chip, struct tpm_space *space, diff --git a/drivers/char/tpm/tpm2-space.c b/drivers/char/tpm/tpm2-space.c index 862ee1ce1755..393d9aadadce 100644 --- a/drivers/char/tpm/tpm2-space.c +++ b/drivers/char/tpm/tpm2-space.c @@ -162,7 +162,7 @@ static int tpm2_save_context(struct tpm_chip *chip, u32 handle, u8 *buf, return 0; } -static void tpm2_flush_space(struct tpm_chip *chip) +void tpm2_flush_space(struct tpm_chip *chip) { struct tpm_space *space = &chip->work_space; int i; -- 2.19.1

5 years, 11 months

2
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FAILED: patch "[PATCH] mm: migration: fix migration of huge PMD shared pages" failed to apply to 4.9-stable tree

by gregkh＠linuxfoundation.org

The patch below does not apply to the 4.9-stable tree. If someone wants it applied there, or to any other stable or longterm tree, then please email the backport, including the original git commit id to <stable(a)vger.kernel.org>. thanks, greg k-h ------------------ original commit in Linus's tree ------------------ >From 017b1660df89f5fb4bfe66c34e35f7d2031100c7 Mon Sep 17 00:00:00 2001 From: Mike Kravetz <mike.kravetz(a)oracle.com> Date: Fri, 5 Oct 2018 15:51:29 -0700 Subject: [PATCH] mm: migration: fix migration of huge PMD shared pages The page migration code employs try_to_unmap() to try and unmap the source page. This is accomplished by using rmap_walk to find all vmas where the page is mapped. This search stops when page mapcount is zero. For shared PMD huge pages, the page map count is always 1 no matter the number of mappings. Shared mappings are tracked via the reference count of the PMD page. Therefore, try_to_unmap stops prematurely and does not completely unmap all mappings of the source page. This problem can result is data corruption as writes to the original source page can happen after contents of the page are copied to the target page. Hence, data is lost. This problem was originally seen as DB corruption of shared global areas after a huge page was soft offlined due to ECC memory errors. DB developers noticed they could reproduce the issue by (hotplug) offlining memory used to back huge pages. A simple testcase can reproduce the problem by creating a shared PMD mapping (note that this must be at least PUD_SIZE in size and PUD_SIZE aligned (1GB on x86)), and using migrate_pages() to migrate process pages between nodes while continually writing to the huge pages being migrated. To fix, have the try_to_unmap_one routine check for huge PMD sharing by calling huge_pmd_unshare for hugetlbfs huge pages. If it is a shared mapping it will be 'unshared' which removes the page table entry and drops the reference on the PMD page. After this, flush caches and TLB. mmu notifiers are called before locking page tables, but we can not be sure of PMD sharing until page tables are locked. Therefore, check for the possibility of PMD sharing before locking so that notifiers can prepare for the worst possible case. Link: http://lkml.kernel.org/r/20180823205917.16297-2-mike.kravetz@oracle.com [mike.kravetz(a)oracle.com: make _range_in_vma() a static inline] Link: http://lkml.kernel.org/r/6063f215-a5c8-2f0c-465a-2c515ddc952d@oracle.com Fixes: 39dde65c9940 ("shared page table for hugetlb page") Signed-off-by: Mike Kravetz <mike.kravetz(a)oracle.com> Acked-by: Kirill A. Shutemov <kirill.shutemov(a)linux.intel.com> Reviewed-by: Naoya Horiguchi <n-horiguchi(a)ah.jp.nec.com> Acked-by: Michal Hocko <mhocko(a)suse.com> Cc: Vlastimil Babka <vbabka(a)suse.cz> Cc: Davidlohr Bueso <dave(a)stgolabs.net> Cc: Jerome Glisse <jglisse(a)redhat.com> Cc: Mike Kravetz <mike.kravetz(a)oracle.com> Cc: <stable(a)vger.kernel.org> Signed-off-by: Andrew Morton <akpm(a)linux-foundation.org> Signed-off-by: Greg Kroah-Hartman <gregkh(a)linuxfoundation.org> diff --git a/include/linux/hugetlb.h b/include/linux/hugetlb.h index 6b68e345f0ca..087fd5f48c91 100644 --- a/include/linux/hugetlb.h +++ b/include/linux/hugetlb.h @@ -140,6 +140,8 @@ pte_t *huge_pte_alloc(struct mm_struct *mm, pte_t *huge_pte_offset(struct mm_struct *mm, unsigned long addr, unsigned long sz); int huge_pmd_unshare(struct mm_struct *mm, unsigned long *addr, pte_t *ptep); +void adjust_range_if_pmd_sharing_possible(struct vm_area_struct *vma, + unsigned long *start, unsigned long *end); struct page *follow_huge_addr(struct mm_struct *mm, unsigned long address, int write); struct page *follow_huge_pd(struct vm_area_struct *vma, @@ -170,6 +172,18 @@ static inline unsigned long hugetlb_total_pages(void) return 0; } +static inline int huge_pmd_unshare(struct mm_struct *mm, unsigned long *addr, + pte_t *ptep) +{ + return 0; +} + +static inline void adjust_range_if_pmd_sharing_possible( + struct vm_area_struct *vma, + unsigned long *start, unsigned long *end) +{ +} + #define follow_hugetlb_page(m,v,p,vs,a,b,i,w,n) ({ BUG(); 0; }) #define follow_huge_addr(mm, addr, write) ERR_PTR(-EINVAL) #define copy_hugetlb_page_range(src, dst, vma) ({ BUG(); 0; }) diff --git a/include/linux/mm.h b/include/linux/mm.h index a61ebe8ad4ca..0416a7204be3 100644 --- a/include/linux/mm.h +++ b/include/linux/mm.h @@ -2455,6 +2455,12 @@ static inline struct vm_area_struct *find_exact_vma(struct mm_struct *mm, return vma; } +static inline bool range_in_vma(struct vm_area_struct *vma, + unsigned long start, unsigned long end) +{ + return (vma && vma->vm_start <= start && end <= vma->vm_end); +} + #ifdef CONFIG_MMU pgprot_t vm_get_page_prot(unsigned long vm_flags); void vma_set_page_prot(struct vm_area_struct *vma); diff --git a/mm/hugetlb.c b/mm/hugetlb.c index 3c21775f196b..b903d746e132 100644 --- a/mm/hugetlb.c +++ b/mm/hugetlb.c @@ -4545,12 +4545,40 @@ static bool vma_shareable(struct vm_area_struct *vma, unsigned long addr) /* * check on proper vm_flags and page table alignment */ - if (vma->vm_flags & VM_MAYSHARE && - vma->vm_start <= base && end <= vma->vm_end) + if (vma->vm_flags & VM_MAYSHARE && range_in_vma(vma, base, end)) return true; return false; } +/* + * Determine if start,end range within vma could be mapped by shared pmd. + * If yes, adjust start and end to cover range associated with possible + * shared pmd mappings. + */ +void adjust_range_if_pmd_sharing_possible(struct vm_area_struct *vma, + unsigned long *start, unsigned long *end) +{ + unsigned long check_addr = *start; + + if (!(vma->vm_flags & VM_MAYSHARE)) + return; + + for (check_addr = *start; check_addr < *end; check_addr += PUD_SIZE) { + unsigned long a_start = check_addr & PUD_MASK; + unsigned long a_end = a_start + PUD_SIZE; + + /* + * If sharing is possible, adjust start/end if necessary. + */ + if (range_in_vma(vma, a_start, a_end)) { + if (a_start < *start) + *start = a_start; + if (a_end > *end) + *end = a_end; + } + } +} + /* * Search for a shareable pmd page for hugetlb. In any case calls pmd_alloc() * and returns the corresponding pte. While this is not necessary for the @@ -4648,6 +4676,11 @@ int huge_pmd_unshare(struct mm_struct *mm, unsigned long *addr, pte_t *ptep) { return 0; } + +void adjust_range_if_pmd_sharing_possible(struct vm_area_struct *vma, + unsigned long *start, unsigned long *end) +{ +} #define want_pmd_share() (0) #endif /* CONFIG_ARCH_WANT_HUGE_PMD_SHARE */ diff --git a/mm/rmap.c b/mm/rmap.c index eb477809a5c0..1e79fac3186b 100644 --- a/mm/rmap.c +++ b/mm/rmap.c @@ -1362,11 +1362,21 @@ static bool try_to_unmap_one(struct page *page, struct vm_area_struct *vma, } /* - * We have to assume the worse case ie pmd for invalidation. Note that - * the page can not be free in this function as call of try_to_unmap() - * must hold a reference on the page. + * For THP, we have to assume the worse case ie pmd for invalidation. + * For hugetlb, it could be much worse if we need to do pud + * invalidation in the case of pmd sharing. + * + * Note that the page can not be free in this function as call of + * try_to_unmap() must hold a reference on the page. */ end = min(vma->vm_end, start + (PAGE_SIZE << compound_order(page))); + if (PageHuge(page)) { + /* + * If sharing is possible, start and end will be adjusted + * accordingly. + */ + adjust_range_if_pmd_sharing_possible(vma, &start, &end); + } mmu_notifier_invalidate_range_start(vma->vm_mm, start, end); while (page_vma_mapped_walk(&pvmw)) { @@ -1409,6 +1419,32 @@ static bool try_to_unmap_one(struct page *page, struct vm_area_struct *vma, subpage = page - page_to_pfn(page) + pte_pfn(*pvmw.pte); address = pvmw.address; + if (PageHuge(page)) { + if (huge_pmd_unshare(mm, &address, pvmw.pte)) { + /* + * huge_pmd_unshare unmapped an entire PMD + * page. There is no way of knowing exactly + * which PMDs may be cached for this mm, so + * we must flush them all. start/end were + * already adjusted above to cover this range. + */ + flush_cache_range(vma, start, end); + flush_tlb_range(vma, start, end); + mmu_notifier_invalidate_range(mm, start, end); + + /* + * The ref count of the PMD page was dropped + * which is part of the way map counting + * is done for shared PMDs. Return 'true' + * here. When there is no other sharing, + * huge_pmd_unshare returns false and we will + * unmap the actual page and drop map count + * to zero. + */ + page_vma_mapped_walk_done(&pvmw); + break; + } + } if (IS_ENABLED(CONFIG_MIGRATION) && (flags & TTU_MIGRATION) &&

5 years, 11 months

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[PATCHv6 0/7] tty: Hold write ldisc sem in tty_reopen()

by Dmitry Safonov

Hi all, Here are fixes that worth to have in the @stable, as they were hit by different people, including Arista on v4.9 stable. And for linux-next - adding lockdep asserts for line discipline changing code, verifying that write ldisc sem will be held forthwith. Mikulas, can you add your tested-by on this patches set again, please? I tried to reproduce reboot issue on qemu-hppa and even built cross-compiler for pa-risc.. but was unlucky in reproducing. Thanks, Dima Changes since v5: - Better commit tags - Hopefully fixed issue with reboot on pa-risc with Debian 5 Changes since v4: - back to lock ldisc with (5*HZ) timeout in tty_reopen() (LKP report link: lkml.kernel.org/r/<1536940609.3185.29.camel(a)arista.com>) - reordered 3/7 with 2/7 for LKP robot Changes since v3: - Added tested-by Mark Rutland (thanks!) - Dropped patch with smp_wmb() - wrong idea - lockdep_assert_held() should be actually lockdep_assert_held_exclusive() - Described why tty_ldisc_open() can be called without ldisc_sem held for pty slave end (o_tty). - Added Peter's patch for dropping self-made lockdep annotations - Fix for a reader(s) of ldisc semaphore waiting for an active reader(s) Changes since v2: - Added reviewed-by tags - Hopefully, fixed reported by 0-day issue. - Added optional fix for wait_readers decrement Changes since v1: - Added tested-by/reported-by tags - Dropped 3/4 (locking tty pair for lockdep sake), Because of that - not adding lockdep_assert_held() in tty_ldisc_open() - Added 4/4 cleanup to inc tty->count only on success of tty_ldisc_reinit() - lock ldisc without (5*HZ) timeout in tty_reopen() v1 link: lkml.kernel.org/r/<20180829022353.23568-1-dima(a)arista.com> v2 link: lkml.kernel.org/r/<20180903165257.29227-1-dima(a)arista.com> v3 link: lkml.kernel.org/r/<20180911014821.26286-1-dima(a)arista.com> v4 link: lkml.kernel.org/r/<20180912001702.18522-1-dima(a)arista.com> Cc: Daniel Axtens <dja(a)axtens.net> Cc: Dmitry Vyukov <dvyukov(a)google.com> Cc: Mark Rutland <mark.rutland(a)arm.com> Cc: Michael Neuling <mikey(a)neuling.org> Cc: Mikulas Patocka <mpatocka(a)redhat.com> Cc: Nathan March <nathan(a)gt.net> Cc: Pasi Kärkkäinen <pasik(a)iki.fi> Cc: Peter Hurley <peter(a)hurleysoftware.com> Cc: Peter Zijlstra <peterz(a)infradead.org> Cc: "Rong, Chen" <rong.a.chen(a)intel.com> Cc: Sergey Senozhatsky <sergey.senozhatsky.work(a)gmail.com> Cc: Tan Xiaojun <tanxiaojun(a)huawei.com> Cc: Tetsuo Handa <penguin-kernel(a)I-love.SAKURA.ne.jp> (please, ignore if I Cc'ed you mistakenly) Dmitry Safonov (6): tty/ldsem: Wake up readers after timed out down_write() tty: Hold tty_ldisc_lock() during tty_reopen() tty: Don't block on IO when ldisc change is pending tty: Simplify tty->count math in tty_reopen() tty/ldsem: Add lockdep asserts for ldisc_sem tty/ldsem: Decrement wait_readers on timeouted down_read() Peter Zijlstra (1): tty/ldsem: Convert to regular lockdep annotations drivers/tty/n_hdlc.c | 4 +-- drivers/tty/n_r3964.c | 2 +- drivers/tty/n_tty.c | 8 +++--- drivers/tty/tty_io.c | 14 ++++++---- drivers/tty/tty_ldisc.c | 16 +++++++++++ drivers/tty/tty_ldsem.c | 62 +++++++++++++++++------------------------ include/linux/tty.h | 7 +++++ 7 files changed, 63 insertions(+), 50 deletions(-) -- 2.19.1

5 years, 11 months

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FAILED: patch "[PATCH] gfs2: Fix iomap buffer head reference counting bug" failed to apply to 4.19-stable tree

by gregkh＠linuxfoundation.org

The patch below does not apply to the 4.19-stable tree. If someone wants it applied there, or to any other stable or longterm tree, then please email the backport, including the original git commit id to <stable(a)vger.kernel.org>. thanks, greg k-h ------------------ original commit in Linus's tree ------------------ >From c26b5aa8ef0d46035060fded475e6ab957b9f69f Mon Sep 17 00:00:00 2001 From: Andreas Gruenbacher <agruenba(a)redhat.com> Date: Sun, 11 Nov 2018 11:15:21 +0000 Subject: [PATCH] gfs2: Fix iomap buffer head reference counting bug GFS2 passes the inode buffer head (dibh) from gfs2_iomap_begin to gfs2_iomap_end in iomap->private. It sets that private pointer in gfs2_iomap_get. Users of gfs2_iomap_get other than gfs2_iomap_begin would have to release iomap->private, but this isn't done correctly, leading to a leak of buffer head references. To fix this, move the code for setting iomap->private from gfs2_iomap_get to gfs2_iomap_begin. Fixes: 64bc06bb32 ("gfs2: iomap buffered write support") Cc: stable(a)vger.kernel.org # v4.19+ Signed-off-by: Andreas Gruenbacher <agruenba(a)redhat.com> Signed-off-by: Linus Torvalds <torvalds(a)linux-foundation.org> diff --git a/fs/gfs2/bmap.c b/fs/gfs2/bmap.c index 38d88fcb6988..0d643306c255 100644 --- a/fs/gfs2/bmap.c +++ b/fs/gfs2/bmap.c @@ -826,7 +826,7 @@ static int gfs2_iomap_get(struct inode *inode, loff_t pos, loff_t length, ret = gfs2_meta_inode_buffer(ip, &dibh); if (ret) goto unlock; - iomap->private = dibh; + mp->mp_bh[0] = dibh; if (gfs2_is_stuffed(ip)) { if (flags & IOMAP_WRITE) { @@ -863,9 +863,6 @@ static int gfs2_iomap_get(struct inode *inode, loff_t pos, loff_t length, len = lblock_stop - lblock + 1; iomap->length = len << inode->i_blkbits; - get_bh(dibh); - mp->mp_bh[0] = dibh; - height = ip->i_height; while ((lblock + 1) * sdp->sd_sb.sb_bsize > sdp->sd_heightsize[height]) height++; @@ -898,8 +895,6 @@ static int gfs2_iomap_get(struct inode *inode, loff_t pos, loff_t length, iomap->bdev = inode->i_sb->s_bdev; unlock: up_read(&ip->i_rw_mutex); - if (ret && dibh) - brelse(dibh); return ret; do_alloc: @@ -980,9 +975,9 @@ static void gfs2_iomap_journaled_page_done(struct inode *inode, loff_t pos, static int gfs2_iomap_begin_write(struct inode *inode, loff_t pos, loff_t length, unsigned flags, - struct iomap *iomap) + struct iomap *iomap, + struct metapath *mp) { - struct metapath mp = { .mp_aheight = 1, }; struct gfs2_inode *ip = GFS2_I(inode); struct gfs2_sbd *sdp = GFS2_SB(inode); unsigned int data_blocks = 0, ind_blocks = 0, rblocks; @@ -996,9 +991,9 @@ static int gfs2_iomap_begin_write(struct inode *inode, loff_t pos, unstuff = gfs2_is_stuffed(ip) && pos + length > gfs2_max_stuffed_size(ip); - ret = gfs2_iomap_get(inode, pos, length, flags, iomap, &mp); + ret = gfs2_iomap_get(inode, pos, length, flags, iomap, mp); if (ret) - goto out_release; + goto out_unlock; alloc_required = unstuff || iomap->type == IOMAP_HOLE; @@ -1013,7 +1008,7 @@ static int gfs2_iomap_begin_write(struct inode *inode, loff_t pos, ret = gfs2_quota_lock_check(ip, &ap); if (ret) - goto out_release; + goto out_unlock; ret = gfs2_inplace_reserve(ip, &ap); if (ret) @@ -1038,17 +1033,15 @@ static int gfs2_iomap_begin_write(struct inode *inode, loff_t pos, ret = gfs2_unstuff_dinode(ip, NULL); if (ret) goto out_trans_end; - release_metapath(&mp); - brelse(iomap->private); - iomap->private = NULL; + release_metapath(mp); ret = gfs2_iomap_get(inode, iomap->offset, iomap->length, - flags, iomap, &mp); + flags, iomap, mp); if (ret) goto out_trans_end; } if (iomap->type == IOMAP_HOLE) { - ret = gfs2_iomap_alloc(inode, iomap, flags, &mp); + ret = gfs2_iomap_alloc(inode, iomap, flags, mp); if (ret) { gfs2_trans_end(sdp); gfs2_inplace_release(ip); @@ -1056,7 +1049,6 @@ static int gfs2_iomap_begin_write(struct inode *inode, loff_t pos, goto out_qunlock; } } - release_metapath(&mp); if (gfs2_is_jdata(ip)) iomap->page_done = gfs2_iomap_journaled_page_done; return 0; @@ -1069,10 +1061,7 @@ static int gfs2_iomap_begin_write(struct inode *inode, loff_t pos, out_qunlock: if (alloc_required) gfs2_quota_unlock(ip); -out_release: - if (iomap->private) - brelse(iomap->private); - release_metapath(&mp); +out_unlock: gfs2_write_unlock(inode); return ret; } @@ -1088,10 +1077,10 @@ static int gfs2_iomap_begin(struct inode *inode, loff_t pos, loff_t length, trace_gfs2_iomap_start(ip, pos, length, flags); if ((flags & IOMAP_WRITE) && !(flags & IOMAP_DIRECT)) { - ret = gfs2_iomap_begin_write(inode, pos, length, flags, iomap); + ret = gfs2_iomap_begin_write(inode, pos, length, flags, iomap, &mp); } else { ret = gfs2_iomap_get(inode, pos, length, flags, iomap, &mp); - release_metapath(&mp); + /* * Silently fall back to buffered I/O for stuffed files or if * we've hot a hole (see gfs2_file_direct_write). @@ -1100,6 +1089,11 @@ static int gfs2_iomap_begin(struct inode *inode, loff_t pos, loff_t length, iomap->type != IOMAP_MAPPED) ret = -ENOTBLK; } + if (!ret) { + get_bh(mp.mp_bh[0]); + iomap->private = mp.mp_bh[0]; + } + release_metapath(&mp); trace_gfs2_iomap_end(ip, iomap, ret); return ret; }

5 years, 11 months

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FAILED: patch "[PATCH] gfs2: Put bitmap buffers in put_super" failed to apply to 4.4-stable tree

by gregkh＠linuxfoundation.org

The patch below does not apply to the 4.4-stable tree. If someone wants it applied there, or to any other stable or longterm tree, then please email the backport, including the original git commit id to <stable(a)vger.kernel.org>. thanks, greg k-h ------------------ original commit in Linus's tree ------------------ >From 10283ea525d30f2e99828978fd04d8427876a7ad Mon Sep 17 00:00:00 2001 From: Andreas Gruenbacher <agruenba(a)redhat.com> Date: Mon, 5 Nov 2018 22:57:24 +0000 Subject: [PATCH] gfs2: Put bitmap buffers in put_super gfs2_put_super calls gfs2_clear_rgrpd to destroy the gfs2_rgrpd objects attached to the resource group glocks. That function should release the buffers attached to the gfs2_bitmap objects (bi_bh), but the call to gfs2_rgrp_brelse for doing that is missing. When gfs2_releasepage later runs across these buffers which are still referenced, it refuses to free them. This causes the pages the buffers are attached to to remain referenced as well. With enough mount/unmount cycles, the system will eventually run out of memory. Fix this by adding the missing call to gfs2_rgrp_brelse in gfs2_clear_rgrpd. (Also fix a gfs2_rgrp_relse -> gfs2_rgrp_brelse typo in a comment.) Fixes: 39b0f1e92908 ("GFS2: Don't brelse rgrp buffer_heads every allocation") Cc: stable(a)vger.kernel.org # v4.2+ Signed-off-by: Andreas Gruenbacher <agruenba(a)redhat.com> diff --git a/fs/gfs2/rgrp.c b/fs/gfs2/rgrp.c index ffe3032b1043..b08a530433ad 100644 --- a/fs/gfs2/rgrp.c +++ b/fs/gfs2/rgrp.c @@ -733,6 +733,7 @@ void gfs2_clear_rgrpd(struct gfs2_sbd *sdp) if (gl) { glock_clear_object(gl, rgd); + gfs2_rgrp_brelse(rgd); gfs2_glock_put(gl); } @@ -1174,7 +1175,7 @@ static u32 count_unlinked(struct gfs2_rgrpd *rgd) * @rgd: the struct gfs2_rgrpd describing the RG to read in * * Read in all of a Resource Group's header and bitmap blocks. - * Caller must eventually call gfs2_rgrp_relse() to free the bitmaps. + * Caller must eventually call gfs2_rgrp_brelse() to free the bitmaps. * * Returns: errno */

5 years, 11 months

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FAILED: patch "[PATCH] gfs2: Put bitmap buffers in put_super" failed to apply to 4.9-stable tree

by gregkh＠linuxfoundation.org

The patch below does not apply to the 4.9-stable tree. If someone wants it applied there, or to any other stable or longterm tree, then please email the backport, including the original git commit id to <stable(a)vger.kernel.org>. thanks, greg k-h ------------------ original commit in Linus's tree ------------------ >From 10283ea525d30f2e99828978fd04d8427876a7ad Mon Sep 17 00:00:00 2001 From: Andreas Gruenbacher <agruenba(a)redhat.com> Date: Mon, 5 Nov 2018 22:57:24 +0000 Subject: [PATCH] gfs2: Put bitmap buffers in put_super gfs2_put_super calls gfs2_clear_rgrpd to destroy the gfs2_rgrpd objects attached to the resource group glocks. That function should release the buffers attached to the gfs2_bitmap objects (bi_bh), but the call to gfs2_rgrp_brelse for doing that is missing. When gfs2_releasepage later runs across these buffers which are still referenced, it refuses to free them. This causes the pages the buffers are attached to to remain referenced as well. With enough mount/unmount cycles, the system will eventually run out of memory. Fix this by adding the missing call to gfs2_rgrp_brelse in gfs2_clear_rgrpd. (Also fix a gfs2_rgrp_relse -> gfs2_rgrp_brelse typo in a comment.) Fixes: 39b0f1e92908 ("GFS2: Don't brelse rgrp buffer_heads every allocation") Cc: stable(a)vger.kernel.org # v4.2+ Signed-off-by: Andreas Gruenbacher <agruenba(a)redhat.com> diff --git a/fs/gfs2/rgrp.c b/fs/gfs2/rgrp.c index ffe3032b1043..b08a530433ad 100644 --- a/fs/gfs2/rgrp.c +++ b/fs/gfs2/rgrp.c @@ -733,6 +733,7 @@ void gfs2_clear_rgrpd(struct gfs2_sbd *sdp) if (gl) { glock_clear_object(gl, rgd); + gfs2_rgrp_brelse(rgd); gfs2_glock_put(gl); } @@ -1174,7 +1175,7 @@ static u32 count_unlinked(struct gfs2_rgrpd *rgd) * @rgd: the struct gfs2_rgrpd describing the RG to read in * * Read in all of a Resource Group's header and bitmap blocks. - * Caller must eventually call gfs2_rgrp_relse() to free the bitmaps. + * Caller must eventually call gfs2_rgrp_brelse() to free the bitmaps. * * Returns: errno */

5 years, 11 months

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FAILED: patch "[PATCH] fuse: fix use-after-free in fuse_direct_IO()" failed to apply to 4.4-stable tree

by gregkh＠linuxfoundation.org

The patch below does not apply to the 4.4-stable tree. If someone wants it applied there, or to any other stable or longterm tree, then please email the backport, including the original git commit id to <stable(a)vger.kernel.org>. thanks, greg k-h ------------------ original commit in Linus's tree ------------------ >From ebacb81273599555a7a19f7754a1451206a5fc4f Mon Sep 17 00:00:00 2001 From: Lukas Czerner <lczerner(a)redhat.com> Date: Fri, 9 Nov 2018 14:51:46 +0100 Subject: [PATCH] fuse: fix use-after-free in fuse_direct_IO() In async IO blocking case the additional reference to the io is taken for it to survive fuse_aio_complete(). In non blocking case this additional reference is not needed, however we still reference io to figure out whether to wait for completion or not. This is wrong and will lead to use-after-free. Fix it by storing blocking information in separate variable. This was spotted by KASAN when running generic/208 fstest. Signed-off-by: Lukas Czerner <lczerner(a)redhat.com> Reported-by: Zorro Lang <zlang(a)redhat.com> Signed-off-by: Miklos Szeredi <mszeredi(a)redhat.com> Fixes: 744742d692e3 ("fuse: Add reference counting for fuse_io_priv") Cc: <stable(a)vger.kernel.org> # v4.6 diff --git a/fs/fuse/file.c b/fs/fuse/file.c index cc2121b37bf5..b52f9baaa3e7 100644 --- a/fs/fuse/file.c +++ b/fs/fuse/file.c @@ -2924,10 +2924,12 @@ fuse_direct_IO(struct kiocb *iocb, struct iov_iter *iter) } if (io->async) { + bool blocking = io->blocking; + fuse_aio_complete(io, ret < 0 ? ret : 0, -1); /* we have a non-extending, async request, so return */ - if (!io->blocking) + if (!blocking) return -EIOCBQUEUED; wait_for_completion(&wait);

5 years, 11 months

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FAILED: patch "[PATCH] ARM: cpuidle: Don't register the driver when back-end init" failed to apply to 4.14-stable tree

by gregkh＠linuxfoundation.org

The patch below does not apply to the 4.14-stable tree. If someone wants it applied there, or to any other stable or longterm tree, then please email the backport, including the original git commit id to <stable(a)vger.kernel.org>. thanks, greg k-h ------------------ original commit in Linus's tree ------------------ >From 763f191af51f127cf8e69cd361f50bf6180768a5 Mon Sep 17 00:00:00 2001 From: Ulf Hansson <ulf.hansson(a)linaro.org> Date: Thu, 1 Nov 2018 13:22:38 +0100 Subject: [PATCH] ARM: cpuidle: Don't register the driver when back-end init returns -ENXIO There's no point to register the cpuidle driver for the current CPU, when the initialization of the arch specific back-end data fails by returning -ENXIO. Instead, let's re-order the sequence to its original flow, by first trying to initialize the back-end part and then act accordingly on the returned error code. Additionally, let's print the error message, no matter of what error code that was returned. Fixes: a0d46a3dfdc3 (ARM: cpuidle: Register per cpuidle device) Signed-off-by: Ulf Hansson <ulf.hansson(a)linaro.org> Reviewed-by: Daniel Lezcano <daniel.lezcano(a)linaro.org> Cc: 4.19+ <stable(a)vger.kernel.org> # v4.19+ Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki(a)intel.com> diff --git a/drivers/cpuidle/cpuidle-arm.c b/drivers/cpuidle/cpuidle-arm.c index 073557f433eb..df564d783216 100644 --- a/drivers/cpuidle/cpuidle-arm.c +++ b/drivers/cpuidle/cpuidle-arm.c @@ -103,13 +103,6 @@ static int __init arm_idle_init_cpu(int cpu) goto out_kfree_drv; } - ret = cpuidle_register_driver(drv); - if (ret) { - if (ret != -EBUSY) - pr_err("Failed to register cpuidle driver\n"); - goto out_kfree_drv; - } - /* * Call arch CPU operations in order to initialize * idle states suspend back-end specific data @@ -117,15 +110,20 @@ static int __init arm_idle_init_cpu(int cpu) ret = arm_cpuidle_init(cpu); /* - * Skip the cpuidle device initialization if the reported + * Allow the initialization to continue for other CPUs, if the reported * failure is a HW misconfiguration/breakage (-ENXIO). */ - if (ret == -ENXIO) - return 0; - if (ret) { pr_err("CPU %d failed to init idle CPU ops\n", cpu); - goto out_unregister_drv; + ret = ret == -ENXIO ? 0 : ret; + goto out_kfree_drv; + } + + ret = cpuidle_register_driver(drv); + if (ret) { + if (ret != -EBUSY) + pr_err("Failed to register cpuidle driver\n"); + goto out_kfree_drv; } dev = kzalloc(sizeof(*dev), GFP_KERNEL);

5 years, 11 months

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FAILED: patch "[PATCH] ARM: cpuidle: Don't register the driver when back-end init" failed to apply to 4.18-stable tree

by gregkh＠linuxfoundation.org

The patch below does not apply to the 4.18-stable tree. If someone wants it applied there, or to any other stable or longterm tree, then please email the backport, including the original git commit id to <stable(a)vger.kernel.org>. thanks, greg k-h ------------------ original commit in Linus's tree ------------------ >From 763f191af51f127cf8e69cd361f50bf6180768a5 Mon Sep 17 00:00:00 2001 From: Ulf Hansson <ulf.hansson(a)linaro.org> Date: Thu, 1 Nov 2018 13:22:38 +0100 Subject: [PATCH] ARM: cpuidle: Don't register the driver when back-end init returns -ENXIO There's no point to register the cpuidle driver for the current CPU, when the initialization of the arch specific back-end data fails by returning -ENXIO. Instead, let's re-order the sequence to its original flow, by first trying to initialize the back-end part and then act accordingly on the returned error code. Additionally, let's print the error message, no matter of what error code that was returned. Fixes: a0d46a3dfdc3 (ARM: cpuidle: Register per cpuidle device) Signed-off-by: Ulf Hansson <ulf.hansson(a)linaro.org> Reviewed-by: Daniel Lezcano <daniel.lezcano(a)linaro.org> Cc: 4.19+ <stable(a)vger.kernel.org> # v4.19+ Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki(a)intel.com> diff --git a/drivers/cpuidle/cpuidle-arm.c b/drivers/cpuidle/cpuidle-arm.c index 073557f433eb..df564d783216 100644 --- a/drivers/cpuidle/cpuidle-arm.c +++ b/drivers/cpuidle/cpuidle-arm.c @@ -103,13 +103,6 @@ static int __init arm_idle_init_cpu(int cpu) goto out_kfree_drv; } - ret = cpuidle_register_driver(drv); - if (ret) { - if (ret != -EBUSY) - pr_err("Failed to register cpuidle driver\n"); - goto out_kfree_drv; - } - /* * Call arch CPU operations in order to initialize * idle states suspend back-end specific data @@ -117,15 +110,20 @@ static int __init arm_idle_init_cpu(int cpu) ret = arm_cpuidle_init(cpu); /* - * Skip the cpuidle device initialization if the reported + * Allow the initialization to continue for other CPUs, if the reported * failure is a HW misconfiguration/breakage (-ENXIO). */ - if (ret == -ENXIO) - return 0; - if (ret) { pr_err("CPU %d failed to init idle CPU ops\n", cpu); - goto out_unregister_drv; + ret = ret == -ENXIO ? 0 : ret; + goto out_kfree_drv; + } + + ret = cpuidle_register_driver(drv); + if (ret) { + if (ret != -EBUSY) + pr_err("Failed to register cpuidle driver\n"); + goto out_kfree_drv; } dev = kzalloc(sizeof(*dev), GFP_KERNEL);

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Linux-stable-mirror November 2018