Linux-stable-mirror February 2023

linux-stable-mirror@lists.linaro.org

353 participants
1255 discussions

[merged mm-hotfixes-stable] mm-mremap-fix-mremap-expanding-for-vmas-with-vm_ops-close.patch removed from -mm tree

by Andrew Morton

The quilt patch titled Subject: mm, mremap: fix mremap() expanding for vma's with vm_ops->close() has been removed from the -mm tree. Its filename was mm-mremap-fix-mremap-expanding-for-vmas-with-vm_ops-close.patch This patch was dropped because it was merged into the mm-hotfixes-stable branch of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm ------------------------------------------------------ From: Vlastimil Babka <vbabka(a)suse.cz> Subject: mm, mremap: fix mremap() expanding for vma's with vm_ops->close() Date: Tue, 17 Jan 2023 11:19:39 +0100 Fabian has reported another regression in 6.1 due to ca3d76b0aa80 ("mm: add merging after mremap resize"). The problem is that vma_merge() can fail when vma has a vm_ops->close() method, causing is_mergeable_vma() test to be negative. This was happening for vma mapping a file from fuse-overlayfs, which does have the method. But when we are simply expanding the vma, we never remove it due to the "merge" with the added area, so the test should not prevent the expansion. As a quick fix, check for such vmas and expand them using vma_adjust() directly as was done before commit ca3d76b0aa80. For a more robust long term solution we should try to limit the check for vma_ops->close only to cases that actually result in vma removal, so that no merge would be prevented unnecessarily. [akpm(a)linux-foundation.org: fix indenting whitespace, reflow comment] Link: https://lkml.kernel.org/r/20230117101939.9753-1-vbabka@suse.cz Fixes: ca3d76b0aa80 ("mm: add merging after mremap resize") Signed-off-by: Vlastimil Babka <vbabka(a)suse.cz> Reported-by: Fabian Vogt <fvogt(a)suse.com> Link: https://bugzilla.suse.com/show_bug.cgi?id=1206359#c35 Tested-by: Fabian Vogt <fvogt(a)suse.com> Cc: Jakub Mat��na <matenajakub(a)gmail.com> Cc: <stable(a)vger.kernel.org> Signed-off-by: Andrew Morton <akpm(a)linux-foundation.org> --- mm/mremap.c | 25 +++++++++++++++++++------ 1 file changed, 19 insertions(+), 6 deletions(-) --- a/mm/mremap.c~mm-mremap-fix-mremap-expanding-for-vmas-with-vm_ops-close +++ a/mm/mremap.c @@ -1027,16 +1027,29 @@ SYSCALL_DEFINE5(mremap, unsigned long, a } /* - * Function vma_merge() is called on the extension we are adding to - * the already existing vma, vma_merge() will merge this extension with - * the already existing vma (expand operation itself) and possibly also - * with the next vma if it becomes adjacent to the expanded vma and - * otherwise compatible. + * Function vma_merge() is called on the extension we + * are adding to the already existing vma, vma_merge() + * will merge this extension with the already existing + * vma (expand operation itself) and possibly also with + * the next vma if it becomes adjacent to the expanded + * vma and otherwise compatible. + * + * However, vma_merge() can currently fail due to + * is_mergeable_vma() check for vm_ops->close (see the + * comment there). Yet this should not prevent vma + * expanding, so perform a simple expand for such vma. + * Ideally the check for close op should be only done + * when a vma would be actually removed due to a merge. */ - vma = vma_merge(mm, vma, extension_start, extension_end, + if (!vma->vm_ops || !vma->vm_ops->close) { + vma = vma_merge(mm, vma, extension_start, extension_end, vma->vm_flags, vma->anon_vma, vma->vm_file, extension_pgoff, vma_policy(vma), vma->vm_userfaultfd_ctx, anon_vma_name(vma)); + } else if (vma_adjust(vma, vma->vm_start, addr + new_len, + vma->vm_pgoff, NULL)) { + vma = NULL; + } if (!vma) { vm_unacct_memory(pages); ret = -ENOMEM; _ Patches currently in -mm which might be from vbabka(a)suse.cz are revert-mm-compaction-fix-set-skip-in-fast_find_migrateblock.patch

2 years, 10 months

[merged mm-hotfixes-stable] ia64-fix-build-error-due-to-switch-case-label-appearing-next-to-declaration.patch removed from -mm tree

by Andrew Morton

The quilt patch titled Subject: ia64: fix build error due to switch case label appearing next to declaration has been removed from the -mm tree. Its filename was ia64-fix-build-error-due-to-switch-case-label-appearing-next-to-declaration.patch This patch was dropped because it was merged into the mm-hotfixes-stable branch of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm ------------------------------------------------------ From: James Morse <james.morse(a)arm.com> Subject: ia64: fix build error due to switch case label appearing next to declaration Date: Tue, 17 Jan 2023 15:16:32 +0000 Since commit aa06a9bd8533 ("ia64: fix clock_getres(CLOCK_MONOTONIC) to report ITC frequency"), gcc 10.1.0 fails to build ia64 with the gnomic: | ../arch/ia64/kernel/sys_ia64.c: In function 'ia64_clock_getres': | ../arch/ia64/kernel/sys_ia64.c:189:3: error: a label can only be part of a statement and a declaration is not a statement | 189 | s64 tick_ns = DIV_ROUND_UP(NSEC_PER_SEC, local_cpu_data->itc_freq); This line appears immediately after a case label in a switch. Move the declarations out of the case, to the top of the function. Link: https://lkml.kernel.org/r/20230117151632.393836-1-james.morse@arm.com Fixes: aa06a9bd8533 ("ia64: fix clock_getres(CLOCK_MONOTONIC) to report ITC frequency") Signed-off-by: James Morse <james.morse(a)arm.com> Reviewed-by: Sergei Trofimovich <slyich(a)gmail.com> Cc: ��meric Maschino <emeric.maschino(a)gmail.com> Cc: matoro <matoro_mailinglist_kernel(a)matoro.tk> Cc: John Paul Adrian Glaubitz <glaubitz(a)physik.fu-berlin.de> Cc: <stable(a)vger.kernel.org> Signed-off-by: Andrew Morton <akpm(a)linux-foundation.org> --- arch/ia64/kernel/sys_ia64.c | 7 +++++-- 1 file changed, 5 insertions(+), 2 deletions(-) --- a/arch/ia64/kernel/sys_ia64.c~ia64-fix-build-error-due-to-switch-case-label-appearing-next-to-declaration +++ a/arch/ia64/kernel/sys_ia64.c @@ -170,6 +170,9 @@ ia64_mremap (unsigned long addr, unsigne asmlinkage long ia64_clock_getres(const clockid_t which_clock, struct __kernel_timespec __user *tp) { + struct timespec64 rtn_tp; + s64 tick_ns; + /* * ia64's clock_gettime() syscall is implemented as a vdso call * fsys_clock_gettime(). Currently it handles only @@ -185,8 +188,8 @@ ia64_clock_getres(const clockid_t which_ switch (which_clock) { case CLOCK_REALTIME: case CLOCK_MONOTONIC: - s64 tick_ns = DIV_ROUND_UP(NSEC_PER_SEC, local_cpu_data->itc_freq); - struct timespec64 rtn_tp = ns_to_timespec64(tick_ns); + tick_ns = DIV_ROUND_UP(NSEC_PER_SEC, local_cpu_data->itc_freq); + rtn_tp = ns_to_timespec64(tick_ns); return put_timespec64(&rtn_tp, tp); } _ Patches currently in -mm which might be from james.morse(a)arm.com are

2 years, 10 months

[merged mm-hotfixes-stable] mm-multi-gen-lru-fix-crash-during-cgroup-migration.patch removed from -mm tree

by Andrew Morton

The quilt patch titled Subject: mm: multi-gen LRU: fix crash during cgroup migration has been removed from the -mm tree. Its filename was mm-multi-gen-lru-fix-crash-during-cgroup-migration.patch This patch was dropped because it was merged into the mm-hotfixes-stable branch of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm ------------------------------------------------------ From: Yu Zhao <yuzhao(a)google.com> Subject: mm: multi-gen LRU: fix crash during cgroup migration Date: Sun, 15 Jan 2023 20:44:05 -0700 lru_gen_migrate_mm() assumes lru_gen_add_mm() runs prior to itself. This isn't true for the following scenario: CPU 1 CPU 2 clone() cgroup_can_fork() cgroup_procs_write() cgroup_post_fork() task_lock() lru_gen_migrate_mm() task_unlock() task_lock() lru_gen_add_mm() task_unlock() And when the above happens, kernel crashes because of linked list corruption (mm_struct->lru_gen.list). Link: https://lore.kernel.org/r/20230115134651.30028-1-msizanoen@qtmlabs.xyz/ Link: https://lkml.kernel.org/r/20230116034405.2960276-1-yuzhao@google.com Fixes: bd74fdaea146 ("mm: multi-gen LRU: support page table walks") Signed-off-by: Yu Zhao <yuzhao(a)google.com> Reported-by: msizanoen <msizanoen(a)qtmlabs.xyz> Tested-by: msizanoen <msizanoen(a)qtmlabs.xyz> Cc: <stable(a)vger.kernel.org> [6.1+] Signed-off-by: Andrew Morton <akpm(a)linux-foundation.org> --- mm/vmscan.c | 5 ++++- 1 file changed, 4 insertions(+), 1 deletion(-) --- a/mm/vmscan.c~mm-multi-gen-lru-fix-crash-during-cgroup-migration +++ a/mm/vmscan.c @@ -3323,13 +3323,16 @@ void lru_gen_migrate_mm(struct mm_struct if (mem_cgroup_disabled()) return; + /* migration can happen before addition */ + if (!mm->lru_gen.memcg) + return; + rcu_read_lock(); memcg = mem_cgroup_from_task(task); rcu_read_unlock(); if (memcg == mm->lru_gen.memcg) return; - VM_WARN_ON_ONCE(!mm->lru_gen.memcg); VM_WARN_ON_ONCE(list_empty(&mm->lru_gen.list)); lru_gen_del_mm(mm); _ Patches currently in -mm which might be from yuzhao(a)google.com are

2 years, 10 months

[merged mm-hotfixes-stable] mm-khugepaged-fix-anon_vma-race.patch removed from -mm tree

by Andrew Morton

The quilt patch titled Subject: mm/khugepaged: fix ->anon_vma race has been removed from the -mm tree. Its filename was mm-khugepaged-fix-anon_vma-race.patch This patch was dropped because it was merged into the mm-hotfixes-stable branch of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm ------------------------------------------------------ From: Jann Horn <jannh(a)google.com> Subject: mm/khugepaged: fix ->anon_vma race Date: Wed, 11 Jan 2023 14:33:51 +0100 If an ->anon_vma is attached to the VMA, collapse_and_free_pmd() requires it to be locked. Page table traversal is allowed under any one of the mmap lock, the anon_vma lock (if the VMA is associated with an anon_vma), and the mapping lock (if the VMA is associated with a mapping); and so to be able to remove page tables, we must hold all three of them. retract_page_tables() bails out if an ->anon_vma is attached, but does this check before holding the mmap lock (as the comment above the check explains). If we racily merged an existing ->anon_vma (shared with a child process) from a neighboring VMA, subsequent rmap traversals on pages belonging to the child will be able to see the page tables that we are concurrently removing while assuming that nothing else can access them. Repeat the ->anon_vma check once we hold the mmap lock to ensure that there really is no concurrent page table access. Hitting this bug causes a lockdep warning in collapse_and_free_pmd(), in the line "lockdep_assert_held_write(&vma->anon_vma->root->rwsem)". It can also lead to use-after-free access. Link: https://lore.kernel.org/linux-mm/CAG48ez3434wZBKFFbdx4M9j6eUwSUVPd4dxhzW_k_… Link: https://lkml.kernel.org/r/20230111133351.807024-1-jannh@google.com Fixes: f3f0e1d2150b ("khugepaged: add support of collapse for tmpfs/shmem pages") Signed-off-by: Jann Horn <jannh(a)google.com> Reported-by: Zach O'Keefe <zokeefe(a)google.com> Acked-by: Kirill A. Shutemov <kirill.shutemov(a)intel.linux.com> Reviewed-by: Yang Shi <shy828301(a)gmail.com> Cc: David Hildenbrand <david(a)redhat.com> Cc: <stable(a)vger.kernel.org> Signed-off-by: Andrew Morton <akpm(a)linux-foundation.org> --- mm/khugepaged.c | 14 +++++++++++++- 1 file changed, 13 insertions(+), 1 deletion(-) --- a/mm/khugepaged.c~mm-khugepaged-fix-anon_vma-race +++ a/mm/khugepaged.c @@ -1642,7 +1642,7 @@ static int retract_page_tables(struct ad * has higher cost too. It would also probably require locking * the anon_vma. */ - if (vma->anon_vma) { + if (READ_ONCE(vma->anon_vma)) { result = SCAN_PAGE_ANON; goto next; } @@ -1671,6 +1671,18 @@ static int retract_page_tables(struct ad if ((cc->is_khugepaged || is_target) && mmap_write_trylock(mm)) { /* + * Re-check whether we have an ->anon_vma, because + * collapse_and_free_pmd() requires that either no + * ->anon_vma exists or the anon_vma is locked. + * We already checked ->anon_vma above, but that check + * is racy because ->anon_vma can be populated under the + * mmap lock in read mode. + */ + if (vma->anon_vma) { + result = SCAN_PAGE_ANON; + goto unlock_next; + } + /* * When a vma is registered with uffd-wp, we can't * recycle the pmd pgtable because there can be pte * markers installed. Skip it only, so the rest mm/vma _ Patches currently in -mm which might be from jannh(a)google.com are

2 years, 10 months

[merged mm-hotfixes-stable] maple_tree-fix-mas_empty_area_rev-lower-bound-validation.patch removed from -mm tree

by Andrew Morton

The quilt patch titled Subject: maple_tree: fix mas_empty_area_rev() lower bound validation has been removed from the -mm tree. Its filename was maple_tree-fix-mas_empty_area_rev-lower-bound-validation.patch This patch was dropped because it was merged into the mm-hotfixes-stable branch of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm ------------------------------------------------------ From: Liam Howlett <liam.howlett(a)oracle.com> Subject: maple_tree: fix mas_empty_area_rev() lower bound validation Date: Wed, 11 Jan 2023 20:02:07 +0000 mas_empty_area_rev() was not correctly validating the start of a gap against the lower limit. This could lead to the range starting lower than the requested minimum. Fix the issue by better validating a gap once one is found. This commit also adds tests to the maple tree test suite for this issue and tests the mas_empty_area() function for similar bound checking. Link: https://lkml.kernel.org/r/20230111200136.1851322-1-Liam.Howlett@oracle.com Link: https://bugzilla.kernel.org/show_bug.cgi?id=216911 Fixes: 54a611b60590 ("Maple Tree: add new data structure") Signed-off-by: Liam R. Howlett <Liam.Howlett(a)oracle.com> Reported-by: <amanieu(a)gmail.com> Link: https://lore.kernel.org/linux-mm/0b9f5425-08d4-8013-aa4c-e620c3b10bb2@leemh… Tested-by: Holger Hoffsttte <holger(a)applied-asynchrony.com> Cc: <stable(a)vger.kernel.org> Signed-off-by: Andrew Morton <akpm(a)linux-foundation.org> --- lib/maple_tree.c | 17 +++---- lib/test_maple_tree.c | 89 ++++++++++++++++++++++++++++++++++++++++ 2 files changed, 97 insertions(+), 9 deletions(-) --- a/lib/maple_tree.c~maple_tree-fix-mas_empty_area_rev-lower-bound-validation +++ a/lib/maple_tree.c @@ -4887,7 +4887,7 @@ static bool mas_rev_awalk(struct ma_stat unsigned long *pivots, *gaps; void __rcu **slots; unsigned long gap = 0; - unsigned long max, min, index; + unsigned long max, min; unsigned char offset; if (unlikely(mas_is_err(mas))) @@ -4909,8 +4909,7 @@ static bool mas_rev_awalk(struct ma_stat min = mas_safe_min(mas, pivots, --offset); max = mas_safe_pivot(mas, pivots, offset, type); - index = mas->index; - while (index <= max) { + while (mas->index <= max) { gap = 0; if (gaps) gap = gaps[offset]; @@ -4941,10 +4940,8 @@ static bool mas_rev_awalk(struct ma_stat min = mas_safe_min(mas, pivots, offset); } - if (unlikely(index > max)) { - mas_set_err(mas, -EBUSY); - return false; - } + if (unlikely((mas->index > max) || (size - 1 > max - mas->index))) + goto no_space; if (unlikely(ma_is_leaf(type))) { mas->offset = offset; @@ -4961,9 +4958,11 @@ static bool mas_rev_awalk(struct ma_stat return false; ascend: - if (mte_is_root(mas->node)) - mas_set_err(mas, -EBUSY); + if (!mte_is_root(mas->node)) + return false; +no_space: + mas_set_err(mas, -EBUSY); return false; } --- a/lib/test_maple_tree.c~maple_tree-fix-mas_empty_area_rev-lower-bound-validation +++ a/lib/test_maple_tree.c @@ -2517,6 +2517,91 @@ static noinline void check_bnode_min_spa mt_set_non_kernel(0); } +static noinline void check_empty_area_window(struct maple_tree *mt) +{ + unsigned long i, nr_entries = 20; + MA_STATE(mas, mt, 0, 0); + + for (i = 1; i <= nr_entries; i++) + mtree_store_range(mt, i*10, i*10 + 9, + xa_mk_value(i), GFP_KERNEL); + + /* Create another hole besides the one at 0 */ + mtree_store_range(mt, 160, 169, NULL, GFP_KERNEL); + + /* Check lower bounds that don't fit */ + rcu_read_lock(); + MT_BUG_ON(mt, mas_empty_area_rev(&mas, 5, 90, 10) != -EBUSY); + + mas_reset(&mas); + MT_BUG_ON(mt, mas_empty_area_rev(&mas, 6, 90, 5) != -EBUSY); + + /* Check lower bound that does fit */ + mas_reset(&mas); + MT_BUG_ON(mt, mas_empty_area_rev(&mas, 5, 90, 5) != 0); + MT_BUG_ON(mt, mas.index != 5); + MT_BUG_ON(mt, mas.last != 9); + rcu_read_unlock(); + + /* Check one gap that doesn't fit and one that does */ + rcu_read_lock(); + mas_reset(&mas); + MT_BUG_ON(mt, mas_empty_area_rev(&mas, 5, 217, 9) != 0); + MT_BUG_ON(mt, mas.index != 161); + MT_BUG_ON(mt, mas.last != 169); + + /* Check one gap that does fit above the min */ + mas_reset(&mas); + MT_BUG_ON(mt, mas_empty_area_rev(&mas, 100, 218, 3) != 0); + MT_BUG_ON(mt, mas.index != 216); + MT_BUG_ON(mt, mas.last != 218); + + /* Check size that doesn't fit any gap */ + mas_reset(&mas); + MT_BUG_ON(mt, mas_empty_area_rev(&mas, 100, 218, 16) != -EBUSY); + + /* + * Check size that doesn't fit the lower end of the window but + * does fit the gap + */ + mas_reset(&mas); + MT_BUG_ON(mt, mas_empty_area_rev(&mas, 167, 200, 4) != -EBUSY); + + /* + * Check size that doesn't fit the upper end of the window but + * does fit the gap + */ + mas_reset(&mas); + MT_BUG_ON(mt, mas_empty_area_rev(&mas, 100, 162, 4) != -EBUSY); + + /* Check mas_empty_area forward */ + mas_reset(&mas); + MT_BUG_ON(mt, mas_empty_area(&mas, 0, 100, 9) != 0); + MT_BUG_ON(mt, mas.index != 0); + MT_BUG_ON(mt, mas.last != 8); + + mas_reset(&mas); + MT_BUG_ON(mt, mas_empty_area(&mas, 0, 100, 4) != 0); + MT_BUG_ON(mt, mas.index != 0); + MT_BUG_ON(mt, mas.last != 3); + + mas_reset(&mas); + MT_BUG_ON(mt, mas_empty_area(&mas, 0, 100, 11) != -EBUSY); + + mas_reset(&mas); + MT_BUG_ON(mt, mas_empty_area(&mas, 5, 100, 6) != -EBUSY); + + mas_reset(&mas); + MT_BUG_ON(mt, mas_empty_area(&mas, 0, 8, 10) != -EBUSY); + + mas_reset(&mas); + mas_empty_area(&mas, 100, 165, 3); + + mas_reset(&mas); + MT_BUG_ON(mt, mas_empty_area(&mas, 100, 163, 6) != -EBUSY); + rcu_read_unlock(); +} + static DEFINE_MTREE(tree); static int maple_tree_seed(void) { @@ -2765,6 +2850,10 @@ static int maple_tree_seed(void) check_bnode_min_spanning(&tree); mtree_destroy(&tree); + mt_init_flags(&tree, MT_FLAGS_ALLOC_RANGE); + check_empty_area_window(&tree); + mtree_destroy(&tree); + #if defined(BENCH) skip: #endif _ Patches currently in -mm which might be from liam.howlett(a)oracle.com are

2 years, 10 months

Jump to page:

2025

2024

2023

2022

2021

2020

2019

2018

2017

Linux-stable-mirror February 2023