From a04cd1600b831a16625b45226b90a292c8f6e8d9 Mon Sep 17 00:00:00 2001 From: Zi Yan Date: Fri, 8 Apr 2022 13:08:52 -0700 Subject: mm: migrate: use thp_order instead of HPAGE_PMD_ORDER for new page allocation. Fix a VM_BUG_ON_FOLIO(folio_nr_pages(old) != nr_pages) crash. With folios support, it is possible to have other than HPAGE_PMD_ORDER THPs, in the form of folios, in the system. Use thp_order() to correctly determine the source page order during migration. Link: https://lkml.kernel.org/r/20220404165325.1883267-1-zi.yan@sent.com Link: https://lore.kernel.org/linux-mm/20220404132908.GA785673@u2004/ Fixes: d68eccad3706 ("mm/filemap: Allow large folios to be added to the page cache") Reported-by: Naoya Horiguchi Signed-off-by: Zi Yan Cc: Matthew Wilcox Cc: Michal Hocko Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- mm/mempolicy.c | 2 +- mm/migrate.c | 2 +- 2 files changed, 2 insertions(+), 2 deletions(-) diff --git a/mm/mempolicy.c b/mm/mempolicy.c index a2516d31db6c..358b7c11426d 100644 --- a/mm/mempolicy.c +++ b/mm/mempolicy.c @@ -1209,7 +1209,7 @@ static struct page *new_page(struct page *page, unsigned long start) struct page *thp; thp = alloc_hugepage_vma(GFP_TRANSHUGE, vma, address, - HPAGE_PMD_ORDER); + thp_order(page)); if (!thp) return NULL; prep_transhuge_page(thp); diff --git a/mm/migrate.c b/mm/migrate.c index de175e2fdba5..79e4b36f709a 100644 --- a/mm/migrate.c +++ b/mm/migrate.c @@ -1547,7 +1547,7 @@ struct page *alloc_migration_target(struct page *page, unsigned long private) */ gfp_mask &= ~__GFP_RECLAIM; gfp_mask |= GFP_TRANSHUGE; - order = HPAGE_PMD_ORDER; + order = thp_order(page); } zidx = zone_idx(page_zone(page)); if (is_highmem_idx(zidx) || zidx == ZONE_MOVABLE) -- cgit v1.3-18-gd494 From 66f133ceab7456c789f70a242991ed1b27ba1c3d Mon Sep 17 00:00:00 2001 From: Max Filippov Date: Fri, 8 Apr 2022 13:08:55 -0700 Subject: highmem: fix checks in __kmap_local_sched_{in,out} When CONFIG_DEBUG_KMAP_LOCAL is enabled __kmap_local_sched_{in,out} check that even slots in the tsk->kmap_ctrl.pteval are unmapped. The slots are initialized with 0 value, but the check is done with pte_none. 0 pte however does not necessarily mean that pte_none will return true. e.g. on xtensa it returns false, resulting in the following runtime warnings: WARNING: CPU: 0 PID: 101 at mm/highmem.c:627 __kmap_local_sched_out+0x51/0x108 CPU: 0 PID: 101 Comm: touch Not tainted 5.17.0-rc7-00010-gd3a1cdde80d2-dirty #13 Call Trace: dump_stack+0xc/0x40 __warn+0x8f/0x174 warn_slowpath_fmt+0x48/0xac __kmap_local_sched_out+0x51/0x108 __schedule+0x71a/0x9c4 preempt_schedule_irq+0xa0/0xe0 common_exception_return+0x5c/0x93 do_wp_page+0x30e/0x330 handle_mm_fault+0xa70/0xc3c do_page_fault+0x1d8/0x3c4 common_exception+0x7f/0x7f WARNING: CPU: 0 PID: 101 at mm/highmem.c:664 __kmap_local_sched_in+0x50/0xe0 CPU: 0 PID: 101 Comm: touch Tainted: G W 5.17.0-rc7-00010-gd3a1cdde80d2-dirty #13 Call Trace: dump_stack+0xc/0x40 __warn+0x8f/0x174 warn_slowpath_fmt+0x48/0xac __kmap_local_sched_in+0x50/0xe0 finish_task_switch$isra$0+0x1ce/0x2f8 __schedule+0x86e/0x9c4 preempt_schedule_irq+0xa0/0xe0 common_exception_return+0x5c/0x93 do_wp_page+0x30e/0x330 handle_mm_fault+0xa70/0xc3c do_page_fault+0x1d8/0x3c4 common_exception+0x7f/0x7f Fix it by replacing !pte_none(pteval) with pte_val(pteval) != 0. Link: https://lkml.kernel.org/r/20220403235159.3498065-1-jcmvbkbc@gmail.com Fixes: 5fbda3ecd14a ("sched: highmem: Store local kmaps in task struct") Signed-off-by: Max Filippov Reviewed-by: Thomas Gleixner Cc: "Peter Zijlstra (Intel)" Cc: Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- mm/highmem.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) diff --git a/mm/highmem.c b/mm/highmem.c index 0cc0c4da7ed9..1a692997fac4 100644 --- a/mm/highmem.c +++ b/mm/highmem.c @@ -624,7 +624,7 @@ void __kmap_local_sched_out(void) /* With debug all even slots are unmapped and act as guard */ if (IS_ENABLED(CONFIG_DEBUG_KMAP_LOCAL) && !(i & 0x01)) { - WARN_ON_ONCE(!pte_none(pteval)); + WARN_ON_ONCE(pte_val(pteval) != 0); continue; } if (WARN_ON_ONCE(pte_none(pteval))) @@ -661,7 +661,7 @@ void __kmap_local_sched_in(void) /* With debug all even slots are unmapped and act as guard */ if (IS_ENABLED(CONFIG_DEBUG_KMAP_LOCAL) && !(i & 0x01)) { - WARN_ON_ONCE(!pte_none(pteval)); + WARN_ON_ONCE(pte_val(pteval) != 0); continue; } if (WARN_ON_ONCE(pte_none(pteval))) -- cgit v1.3-18-gd494 From eafc0a02391b7b36617b36c97c4b5d6832cf5e24 Mon Sep 17 00:00:00 2001 From: Guo Xuenan Date: Fri, 8 Apr 2022 13:08:58 -0700 Subject: lz4: fix LZ4_decompress_safe_partial read out of bound When partialDecoding, it is EOF if we've either filled the output buffer or can't proceed with reading an offset for following match. In some extreme corner cases when compressed data is suitably corrupted, UAF will occur. As reported by KASAN [1], LZ4_decompress_safe_partial may lead to read out of bound problem during decoding. lz4 upstream has fixed it [2] and this issue has been disscussed here [3] before. current decompression routine was ported from lz4 v1.8.3, bumping lib/lz4 to v1.9.+ is certainly a huge work to be done later, so, we'd better fix it first. [1] https://lore.kernel.org/all/000000000000830d1205cf7f0477@google.com/ [2] https://github.com/lz4/lz4/commit/c5d6f8a8be3927c0bec91bcc58667a6cfad244ad# [3] https://lore.kernel.org/all/CC666AE8-4CA4-4951-B6FB-A2EFDE3AC03B@fb.com/ Link: https://lkml.kernel.org/r/20211111105048.2006070-1-guoxuenan@huawei.com Reported-by: syzbot+63d688f1d899c588fb71@syzkaller.appspotmail.com Signed-off-by: Guo Xuenan Reviewed-by: Nick Terrell Acked-by: Gao Xiang Cc: Yann Collet Cc: Chengyang Fan Cc: Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- lib/lz4/lz4_decompress.c | 8 ++++++-- 1 file changed, 6 insertions(+), 2 deletions(-) diff --git a/lib/lz4/lz4_decompress.c b/lib/lz4/lz4_decompress.c index 926f4823d5ea..fd1728d94bab 100644 --- a/lib/lz4/lz4_decompress.c +++ b/lib/lz4/lz4_decompress.c @@ -271,8 +271,12 @@ static FORCE_INLINE int LZ4_decompress_generic( ip += length; op += length; - /* Necessarily EOF, due to parsing restrictions */ - if (!partialDecoding || (cpy == oend)) + /* Necessarily EOF when !partialDecoding. + * When partialDecoding, it is EOF if we've either + * filled the output buffer or + * can't proceed with reading an offset for following match. + */ + if (!partialDecoding || (cpy == oend) || (ip >= (iend - 2))) break; } else { /* may overwrite up to WILDCOPYLENGTH beyond cpy */ -- cgit v1.3-18-gd494 From a431dbbc540532b7465eae4fc8b56a85a9fc7d17 Mon Sep 17 00:00:00 2001 From: Waiman Long Date: Fri, 8 Apr 2022 13:09:01 -0700 Subject: mm/sparsemem: fix 'mem_section' will never be NULL gcc 12 warning The gcc 12 compiler reports a "'mem_section' will never be NULL" warning on the following code: static inline struct mem_section *__nr_to_section(unsigned long nr) { #ifdef CONFIG_SPARSEMEM_EXTREME if (!mem_section) return NULL; #endif if (!mem_section[SECTION_NR_TO_ROOT(nr)]) return NULL; : It happens with CONFIG_SPARSEMEM_EXTREME off. The mem_section definition is #ifdef CONFIG_SPARSEMEM_EXTREME extern struct mem_section **mem_section; #else extern struct mem_section mem_section[NR_SECTION_ROOTS][SECTIONS_PER_ROOT]; #endif In the !CONFIG_SPARSEMEM_EXTREME case, mem_section is a static 2-dimensional array and so the check "!mem_section[SECTION_NR_TO_ROOT(nr)]" doesn't make sense. Fix this warning by moving the "!mem_section[SECTION_NR_TO_ROOT(nr)]" check up inside the CONFIG_SPARSEMEM_EXTREME block and adding an explicit NR_SECTION_ROOTS check to make sure that there is no out-of-bound array access. Link: https://lkml.kernel.org/r/20220331180246.2746210-1-longman@redhat.com Fixes: 3e347261a80b ("sparsemem extreme implementation") Signed-off-by: Waiman Long Reported-by: Justin Forbes Cc: "Kirill A . Shutemov" Cc: Ingo Molnar Cc: Rafael Aquini Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- include/linux/mmzone.h | 11 +++++++---- 1 file changed, 7 insertions(+), 4 deletions(-) diff --git a/include/linux/mmzone.h b/include/linux/mmzone.h index 962b14d403e8..46ffab808f03 100644 --- a/include/linux/mmzone.h +++ b/include/linux/mmzone.h @@ -1397,13 +1397,16 @@ static inline unsigned long *section_to_usemap(struct mem_section *ms) static inline struct mem_section *__nr_to_section(unsigned long nr) { + unsigned long root = SECTION_NR_TO_ROOT(nr); + + if (unlikely(root >= NR_SECTION_ROOTS)) + return NULL; + #ifdef CONFIG_SPARSEMEM_EXTREME - if (!mem_section) + if (!mem_section || !mem_section[root]) return NULL; #endif - if (!mem_section[SECTION_NR_TO_ROOT(nr)]) - return NULL; - return &mem_section[SECTION_NR_TO_ROOT(nr)][nr & SECTION_ROOT_MASK]; + return &mem_section[root][nr & SECTION_ROOT_MASK]; } extern size_t mem_section_usage_size(void); -- cgit v1.3-18-gd494 From 01e67e04c28170c47700c2c226d732bbfedb1ad0 Mon Sep 17 00:00:00 2001 From: Paolo Bonzini Date: Fri, 8 Apr 2022 13:09:04 -0700 Subject: mmmremap.c: avoid pointless invalidate_range_start/end on mremap(old_size=0) If an mremap() syscall with old_size=0 ends up in move_page_tables(), it will call invalidate_range_start()/invalidate_range_end() unnecessarily, i.e. with an empty range. This causes a WARN in KVM's mmu_notifier. In the past, empty ranges have been diagnosed to be off-by-one bugs, hence the WARNing. Given the low (so far) number of unique reports, the benefits of detecting more buggy callers seem to outweigh the cost of having to fix cases such as this one, where userspace is doing something silly. In this particular case, an early return from move_page_tables() is enough to fix the issue. Link: https://lkml.kernel.org/r/20220329173155.172439-1-pbonzini@redhat.com Reported-by: syzbot+6bde52d89cfdf9f61425@syzkaller.appspotmail.com Signed-off-by: Paolo Bonzini Cc: Sean Christopherson Cc: Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- mm/mremap.c | 3 +++ 1 file changed, 3 insertions(+) diff --git a/mm/mremap.c b/mm/mremap.c index 9d76da79594d..303d3290b938 100644 --- a/mm/mremap.c +++ b/mm/mremap.c @@ -486,6 +486,9 @@ unsigned long move_page_tables(struct vm_area_struct *vma, pmd_t *old_pmd, *new_pmd; pud_t *old_pud, *new_pud; + if (!len) + return 0; + old_end = old_addr + len; flush_cache_range(vma, old_addr, old_end); -- cgit v1.3-18-gd494 From 4ad099559b00ac01c3726e5c95dc3108ef47d03e Mon Sep 17 00:00:00 2001 From: Miaohe Lin Date: Fri, 8 Apr 2022 13:09:07 -0700 Subject: mm/mempolicy: fix mpol_new leak in shared_policy_replace If mpol_new is allocated but not used in restart loop, mpol_new will be freed via mpol_put before returning to the caller. But refcnt is not initialized yet, so mpol_put could not do the right things and might leak the unused mpol_new. This would happen if mempolicy was updated on the shared shmem file while the sp->lock has been dropped during the memory allocation. This issue could be triggered easily with the below code snippet if there are many processes doing the below work at the same time: shmid = shmget((key_t)5566, 1024 * PAGE_SIZE, 0666|IPC_CREAT); shm = shmat(shmid, 0, 0); loop many times { mbind(shm, 1024 * PAGE_SIZE, MPOL_LOCAL, mask, maxnode, 0); mbind(shm + 128 * PAGE_SIZE, 128 * PAGE_SIZE, MPOL_DEFAULT, mask, maxnode, 0); } Link: https://lkml.kernel.org/r/20220329111416.27954-1-linmiaohe@huawei.com Fixes: 42288fe366c4 ("mm: mempolicy: Convert shared_policy mutex to spinlock") Signed-off-by: Miaohe Lin Acked-by: Michal Hocko Cc: KOSAKI Motohiro Cc: Mel Gorman Cc: [3.8] Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- mm/mempolicy.c | 1 + 1 file changed, 1 insertion(+) diff --git a/mm/mempolicy.c b/mm/mempolicy.c index 358b7c11426d..88a74bc4cba5 100644 --- a/mm/mempolicy.c +++ b/mm/mempolicy.c @@ -2733,6 +2733,7 @@ alloc_new: mpol_new = kmem_cache_alloc(policy_cache, GFP_KERNEL); if (!mpol_new) goto err_out; + atomic_set(&mpol_new->refcnt, 1); goto restart; } -- cgit v1.3-18-gd494 From 0347b2b95c3e1474c4b10f53df7ff2e841fda147 Mon Sep 17 00:00:00 2001 From: Vasily Averin Date: Fri, 8 Apr 2022 13:09:10 -0700 Subject: mailmap: update Vasily Averin's email address I'm moving to a @linux.dev account. Map my old addresses. Link: https://lkml.kernel.org/r/737c7c2b-cdab-63ee-be90-cb33316c9657@linux.dev Signed-off-by: Vasily Averin Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- .mailmap | 4 ++++ 1 file changed, 4 insertions(+) diff --git a/.mailmap b/.mailmap index b9d358217586..93458154ce7d 100644 --- a/.mailmap +++ b/.mailmap @@ -391,6 +391,10 @@ Uwe Kleine-König Uwe Kleine-König Uwe Kleine-König Valdis Kletnieks +Vasily Averin +Vasily Averin +Vasily Averin +Vasily Averin Vinod Koul Vinod Koul Vinod Koul -- cgit v1.3-18-gd494 From b33e1044475afffaaabe51d35837aa10c09ba9ae Mon Sep 17 00:00:00 2001 From: Andrew Morton Date: Fri, 8 Apr 2022 13:09:13 -0700 Subject: mm/list_lru.c: revert "mm/list_lru: optimize memcg_reparent_list_lru_node()" Commit 405cc51fc104 ("mm/list_lru: optimize memcg_reparent_list_lru_node()") has subtle races which are proving ugly to fix. Revert the original optimization. If quantitative testing indicates that we have a significant problem here then other implementations can be looked at. Fixes: 405cc51fc104 ("mm/list_lru: optimize memcg_reparent_list_lru_node()") Acked-by: Shakeel Butt Reviewed-by: Muchun Song Acked-by: Michal Hocko Cc: Waiman Long Cc: Roman Gushchin Cc: Johannes Weiner Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- mm/list_lru.c | 6 ------ 1 file changed, 6 deletions(-) diff --git a/mm/list_lru.c b/mm/list_lru.c index c669d87001a6..ba76428ceece 100644 --- a/mm/list_lru.c +++ b/mm/list_lru.c @@ -394,12 +394,6 @@ static void memcg_reparent_list_lru_node(struct list_lru *lru, int nid, int dst_idx = dst_memcg->kmemcg_id; struct list_lru_one *src, *dst; - /* - * If there is no lru entry in this nlru, we can skip it immediately. - */ - if (!READ_ONCE(nlru->nr_items)) - return; - /* * Since list_lru_{add,del} may be called under an IRQ-safe lock, * we have to use IRQ-safe primitives here to avoid deadlock. -- cgit v1.3-18-gd494 From 4071a1b9e24ee394b7492bff7542707ee9ad986d Mon Sep 17 00:00:00 2001 From: Tom Rix Date: Fri, 8 Apr 2022 13:09:16 -0700 Subject: MAINTAINERS: add Tom as clang reviewer I have been helping with build breaks and other clang things and would like to help with the reviews. Link: https://lkml.kernel.org/r/20220407175715.3378998-1-trix@redhat.com Signed-off-by: Tom Rix Acked-by: Nathan Chancellor Acked-by: Nick Desaulniers Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- MAINTAINERS | 1 + 1 file changed, 1 insertion(+) diff --git a/MAINTAINERS b/MAINTAINERS index 3af36d852c38..17156b0a8925 100644 --- a/MAINTAINERS +++ b/MAINTAINERS @@ -4791,6 +4791,7 @@ F: .clang-format CLANG/LLVM BUILD SUPPORT M: Nathan Chancellor M: Nick Desaulniers +R: Tom Rix L: llvm@lists.linux.dev S: Supported W: https://clangbuiltlinux.github.io/ -- cgit v1.3-18-gd494