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* Merge tag 'folio-5.18c' of git://git.infradead.org/users/willy/pagecacheLinus Torvalds2022-03-221-30/+2
|\ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Pull folio updates from Matthew Wilcox: - Rewrite how munlock works to massively reduce the contention on i_mmap_rwsem (Hugh Dickins): https://lore.kernel.org/linux-mm/8e4356d-9622-a7f0-b2c-f116b5f2efea@google.com/ - Sort out the page refcount mess for ZONE_DEVICE pages (Christoph Hellwig): https://lore.kernel.org/linux-mm/20220210072828.2930359-1-hch@lst.de/ - Convert GUP to use folios and make pincount available for order-1 pages. (Matthew Wilcox) - Convert a few more truncation functions to use folios (Matthew Wilcox) - Convert page_vma_mapped_walk to use PFNs instead of pages (Matthew Wilcox) - Convert rmap_walk to use folios (Matthew Wilcox) - Convert most of shrink_page_list() to use a folio (Matthew Wilcox) - Add support for creating large folios in readahead (Matthew Wilcox) * tag 'folio-5.18c' of git://git.infradead.org/users/willy/pagecache: (114 commits) mm/damon: minor cleanup for damon_pa_young selftests/vm/transhuge-stress: Support file-backed PMD folios mm/filemap: Support VM_HUGEPAGE for file mappings mm/readahead: Switch to page_cache_ra_order mm/readahead: Align file mappings for non-DAX mm/readahead: Add large folio readahead mm: Support arbitrary THP sizes mm: Make large folios depend on THP mm: Fix READ_ONLY_THP warning mm/filemap: Allow large folios to be added to the page cache mm: Turn can_split_huge_page() into can_split_folio() mm/vmscan: Convert pageout() to take a folio mm/vmscan: Turn page_check_references() into folio_check_references() mm/vmscan: Account large folios correctly mm/vmscan: Optimise shrink_page_list for non-PMD-sized folios mm/vmscan: Free non-shmem folios without splitting them mm/rmap: Constify the rmap_walk_control argument mm/rmap: Convert rmap_walk() to take a folio mm: Turn page_anon_vma() into folio_anon_vma() mm/rmap: Turn page_lock_anon_vma_read() into folio_lock_anon_vma_read() ...
| * mm/munlock: delete munlock_vma_pages_all(), allow oomreapHugh Dickins2022-02-171-30/+2
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | munlock_vma_pages_range() will still be required, when munlocking but not munmapping a set of pages; but when unmapping a pte, the mlock count will be maintained in much the same way as it will be maintained when mapping in the pte. Which removes the need for munlock_vma_pages_all() on mlocked vmas when munmapping or exiting: eliminating the catastrophic contention on i_mmap_rwsem, and the need for page lock on the pages. There is still a need to update locked_vm accounting according to the munmapped vmas when munmapping: do that in detach_vmas_to_be_unmapped(). exit_mmap() does not need locked_vm updates, so delete unlock_range(). And wasn't I the one who forbade the OOM reaper to attack mlocked vmas, because of the uncertainty in blocking on all those page locks? No fear of that now, so permit the OOM reaper on mlocked vmas. Signed-off-by: Hugh Dickins <hughd@google.com> Acked-by: Vlastimil Babka <vbabka@suse.cz> Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org>
* | mm/mmap: remove obsolete comment in ksys_mmap_pgoffMiaohe Lin2022-03-221-2/+0
| | | | | | | | | | | | | | | | | | | | | | | | | | RLIMIT_MEMLOCK is already reimplemented on top of ucounts now. And since commit 83c1fd763b32 ("mm,hugetlb: remove mlock ulimit for SHM_HUGETLB"), mlock ulimit for SHM_HUGETLB is further removed. So we should remove this obsolete comment. Link: https://lkml.kernel.org/r/20220309090623.13036-1-linmiaohe@huawei.com Signed-off-by: Miaohe Lin <linmiaohe@huawei.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* | mm: _install_special_mapping() apply VM_LOCKED_CLEAR_MASKHugh Dickins2022-03-221-0/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | _install_special_mapping() adds the VM_SPECIAL bit VM_DONTEXPAND (and never attempts to update locked_vm), so it ought to be consistent with mmap_region() and mlock_fixup(), making sure not to add VM_LOCKED or VM_LOCKONFAULT. I doubt that this fixes any problem in practice: just do it for consistency. Link: https://lkml.kernel.org/r/a85315a9-21d1-6133-c5fc-c89863dfb25b@google.com Signed-off-by: Hugh Dickins <hughd@google.com> Cc: Vlastimil Babka <vbabka@suse.cz> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* | mm/mmap: return 1 from stack_guard_gap __setup() handlerRandy Dunlap2022-03-221-1/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | __setup() handlers should return 1 if the command line option is handled and 0 if not (or maybe never return 0; it just pollutes init's environment). This prevents: Unknown kernel command line parameters \ "BOOT_IMAGE=/boot/bzImage-517rc5 stack_guard_gap=100", will be \ passed to user space. Run /sbin/init as init process with arguments: /sbin/init with environment: HOME=/ TERM=linux BOOT_IMAGE=/boot/bzImage-517rc5 stack_guard_gap=100 Return 1 to indicate that the boot option has been handled. Note that there is no warning message if someone enters: stack_guard_gap=anything_invalid and 'val' and stack_guard_gap are both set to 0 due to the use of simple_strtoul(). This could be improved by using kstrtoxxx() and checking for an error. It appears that having stack_guard_gap == 0 is valid (if unexpected) since using "stack_guard_gap=0" on the kernel command line does that. Link: https://lkml.kernel.org/r/20220222005817.11087-1-rdunlap@infradead.org Link: lore.kernel.org/r/64644a2f-4a20-bab3-1e15-3b2cdd0defe3@omprussia.ru Fixes: 1be7107fbe18e ("mm: larger stack guard gap, between vmas") Signed-off-by: Randy Dunlap <rdunlap@infradead.org> Reported-by: Igor Zhbanov <i.zhbanov@omprussia.ru> Cc: Hugh Dickins <hughd@google.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* | mm: refactor vm_area_struct::anon_vma_name usage codeSuren Baghdasaryan2022-03-051-6/+6
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Avoid mixing strings and their anon_vma_name referenced pointers by using struct anon_vma_name whenever possible. This simplifies the code and allows easier sharing of anon_vma_name structures when they represent the same name. [surenb@google.com: fix comment] Link: https://lkml.kernel.org/r/20220223153613.835563-1-surenb@google.com Link: https://lkml.kernel.org/r/20220224231834.1481408-1-surenb@google.com Signed-off-by: Suren Baghdasaryan <surenb@google.com> Suggested-by: Matthew Wilcox <willy@infradead.org> Suggested-by: Michal Hocko <mhocko@suse.com> Acked-by: Michal Hocko <mhocko@suse.com> Cc: Colin Cross <ccross@google.com> Cc: Sumit Semwal <sumit.semwal@linaro.org> Cc: Dave Hansen <dave.hansen@intel.com> Cc: Kees Cook <keescook@chromium.org> Cc: "Kirill A. Shutemov" <kirill.shutemov@linux.intel.com> Cc: Vlastimil Babka <vbabka@suse.cz> Cc: Johannes Weiner <hannes@cmpxchg.org> Cc: "Eric W. Biederman" <ebiederm@xmission.com> Cc: Christian Brauner <brauner@kernel.org> Cc: Alexey Gladkov <legion@kernel.org> Cc: Sasha Levin <sashal@kernel.org> Cc: Chris Hyser <chris.hyser@oracle.com> Cc: Davidlohr Bueso <dave@stgolabs.net> Cc: Peter Collingbourne <pcc@google.com> Cc: Xiaofeng Cao <caoxiaofeng@yulong.com> Cc: David Hildenbrand <david@redhat.com> Cc: Cyrill Gorcunov <gorcunov@gmail.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* | mm: fix use-after-free bug when mm->mmap is reused after being freedSuren Baghdasaryan2022-02-261-0/+1
|/ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | oom reaping (__oom_reap_task_mm) relies on a 2 way synchronization with exit_mmap. First it relies on the mmap_lock to exclude from unlock path[1], page tables tear down (free_pgtables) and vma destruction. This alone is not sufficient because mm->mmap is never reset. For historical reasons[2] the lock is taken there is also MMF_OOM_SKIP set for oom victims before. The oom reaper only ever looks at oom victims so the whole scheme works properly but process_mrelease can opearate on any task (with fatal signals pending) which doesn't really imply oom victims. That means that the MMF_OOM_SKIP part of the synchronization doesn't work and it can see a task after the whole address space has been demolished and traverse an already released mm->mmap list. This leads to use after free as properly caught up by KASAN report. Fix the issue by reseting mm->mmap so that MMF_OOM_SKIP synchronization is not needed anymore. The MMF_OOM_SKIP is not removed from exit_mmap yet but it acts mostly as an optimization now. [1] 27ae357fa82b ("mm, oom: fix concurrent munlock and oom reaper unmap, v3") [2] 212925802454 ("mm: oom: let oom_reap_task and exit_mmap run concurrently") [mhocko@suse.com: changelog rewrite] Link: https://lore.kernel.org/all/00000000000072ef2c05d7f81950@google.com/ Link: https://lkml.kernel.org/r/20220215201922.1908156-1-surenb@google.com Fixes: 64591e8605d6 ("mm: protect free_pgtables with mmap_lock write lock in exit_mmap") Signed-off-by: Suren Baghdasaryan <surenb@google.com> Reported-by: syzbot+2ccf63a4bd07cf39cab0@syzkaller.appspotmail.com Suggested-by: Michal Hocko <mhocko@suse.com> Reviewed-by: Rik van Riel <riel@surriel.com> Reviewed-by: Yang Shi <shy828301@gmail.com> Acked-by: Michal Hocko <mhocko@suse.com> Cc: David Rientjes <rientjes@google.com> Cc: Matthew Wilcox <willy@infradead.org> Cc: Johannes Weiner <hannes@cmpxchg.org> Cc: Roman Gushchin <roman.gushchin@linux.dev> Cc: Rik van Riel <riel@surriel.com> Cc: Minchan Kim <minchan@kernel.org> Cc: Kirill A. Shutemov <kirill@shutemov.name> Cc: Andrea Arcangeli <aarcange@redhat.com> Cc: Christian Brauner <brauner@kernel.org> Cc: Christoph Hellwig <hch@infradead.org> Cc: Oleg Nesterov <oleg@redhat.com> Cc: David Hildenbrand <david@redhat.com> Cc: Jann Horn <jannh@google.com> Cc: Shakeel Butt <shakeelb@google.com> Cc: Andy Lutomirski <luto@kernel.org> Cc: Christian Brauner <christian.brauner@ubuntu.com> Cc: Florian Weimer <fweimer@redhat.com> Cc: Jan Engelhardt <jengelh@inai.de> Cc: Tim Murray <timmurray@google.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* Merge branch 'signal-for-v5.17' of ↵Linus Torvalds2022-01-171-1/+0
|\ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/ebiederm/user-namespace Pull signal/exit/ptrace updates from Eric Biederman: "This set of changes deletes some dead code, makes a lot of cleanups which hopefully make the code easier to follow, and fixes bugs found along the way. The end-game which I have not yet reached yet is for fatal signals that generate coredumps to be short-circuit deliverable from complete_signal, for force_siginfo_to_task not to require changing userspace configured signal delivery state, and for the ptrace stops to always happen in locations where we can guarantee on all architectures that the all of the registers are saved and available on the stack. Removal of profile_task_ext, profile_munmap, and profile_handoff_task are the big successes for dead code removal this round. A bunch of small bug fixes are included, as most of the issues reported were small enough that they would not affect bisection so I simply added the fixes and did not fold the fixes into the changes they were fixing. There was a bug that broke coredumps piped to systemd-coredump. I dropped the change that caused that bug and replaced it entirely with something much more restrained. Unfortunately that required some rebasing. Some successes after this set of changes: There are few enough calls to do_exit to audit in a reasonable amount of time. The lifetime of struct kthread now matches the lifetime of struct task, and the pointer to struct kthread is no longer stored in set_child_tid. The flag SIGNAL_GROUP_COREDUMP is removed. The field group_exit_task is removed. Issues where task->exit_code was examined with signal->group_exit_code should been examined were fixed. There are several loosely related changes included because I am cleaning up and if I don't include them they will probably get lost. The original postings of these changes can be found at: https://lkml.kernel.org/r/87a6ha4zsd.fsf@email.froward.int.ebiederm.org https://lkml.kernel.org/r/87bl1kunjj.fsf@email.froward.int.ebiederm.org https://lkml.kernel.org/r/87r19opkx1.fsf_-_@email.froward.int.ebiederm.org I trimmed back the last set of changes to only the obviously correct once. Simply because there was less time for review than I had hoped" * 'signal-for-v5.17' of git://git.kernel.org/pub/scm/linux/kernel/git/ebiederm/user-namespace: (44 commits) ptrace/m68k: Stop open coding ptrace_report_syscall ptrace: Remove unused regs argument from ptrace_report_syscall ptrace: Remove second setting of PT_SEIZED in ptrace_attach taskstats: Cleanup the use of task->exit_code exit: Use the correct exit_code in /proc/<pid>/stat exit: Fix the exit_code for wait_task_zombie exit: Coredumps reach do_group_exit exit: Remove profile_handoff_task exit: Remove profile_task_exit & profile_munmap signal: clean up kernel-doc comments signal: Remove the helper signal_group_exit signal: Rename group_exit_task group_exec_task coredump: Stop setting signal->group_exit_task signal: Remove SIGNAL_GROUP_COREDUMP signal: During coredumps set SIGNAL_GROUP_EXIT in zap_process signal: Make coredump handling explicit in complete_signal signal: Have prepare_signal detect coredumps using signal->core_state signal: Have the oom killer detect coredumps using signal->core_state exit: Move force_uaccess back into do_exit exit: Guarantee make_task_dead leaks the tsk when calling do_task_exit ...
| * exit: Remove profile_task_exit & profile_munmapEric W. Biederman2022-01-081-1/+0
| | | | | | | | | | | | | | | | | | | | | | | | | | When I say remove I mean remove. All profile_task_exit and profile_munmap do is call a blocking notifier chain. The helpers profile_task_register and profile_task_unregister are not called anywhere in the tree. Which means this is all dead code. So remove the dead code and make it easier to read do_exit. Reviewed-by: Christoph Hellwig <hch@lst.de> Link: https://lkml.kernel.org/r/20220103213312.9144-1-ebiederm@xmission.com Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
* | mm: protect free_pgtables with mmap_lock write lock in exit_mmapSuren Baghdasaryan2022-01-151-8/+8
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | oom-reaper and process_mrelease system call should protect against races with exit_mmap which can destroy page tables while they walk the VMA tree. oom-reaper protects from that race by setting MMF_OOM_VICTIM and by relying on exit_mmap to set MMF_OOM_SKIP before taking and releasing mmap_write_lock. process_mrelease has to elevate mm->mm_users to prevent such race. Both oom-reaper and process_mrelease hold mmap_read_lock when walking the VMA tree. The locking rules and mechanisms could be simpler if exit_mmap takes mmap_write_lock while executing destructive operations such as free_pgtables. Change exit_mmap to hold the mmap_write_lock when calling unlock_range, free_pgtables and remove_vma. Note also that because oom-reaper checks VM_LOCKED flag, unlock_range() should not be allowed to race with it. Before this patch, remove_vma used to be called with no locks held, however with fput being executed asynchronously and vm_ops->close not being allowed to hold mmap_lock (it is called from __split_vma with mmap_sem held for write), changing that should be fine. In most cases this lock should be uncontended. Previously, Kirill reported ~4% regression caused by a similar change [1]. We reran the same test and although the individual results are quite noisy, the percentiles show lower regression with 1.6% being the worst case [2]. The change allows oom-reaper and process_mrelease to execute safely under mmap_read_lock without worries that exit_mmap might destroy page tables from under them. [1] https://lore.kernel.org/all/20170725141723.ivukwhddk2voyhuc@node.shutemov.name/ [2] https://lore.kernel.org/all/CAJuCfpGC9-c9P40x7oy=jy5SphMcd0o0G_6U1-+JAziGKG6dGA@mail.gmail.com/ Link: https://lkml.kernel.org/r/20211209191325.3069345-1-surenb@google.com Signed-off-by: Suren Baghdasaryan <surenb@google.com> Acked-by: Michal Hocko <mhocko@suse.com> Cc: David Rientjes <rientjes@google.com> Cc: Matthew Wilcox <willy@infradead.org> Cc: Johannes Weiner <hannes@cmpxchg.org> Cc: Roman Gushchin <guro@fb.com> Cc: Rik van Riel <riel@surriel.com> Cc: Minchan Kim <minchan@kernel.org> Cc: Kirill A. Shutemov <kirill@shutemov.name> Cc: Andrea Arcangeli <aarcange@redhat.com> Cc: Christian Brauner <christian@brauner.io> Cc: Christoph Hellwig <hch@infradead.org> Cc: Oleg Nesterov <oleg@redhat.com> Cc: David Hildenbrand <david@redhat.com> Cc: Jann Horn <jannh@google.com> Cc: Shakeel Butt <shakeelb@google.com> Cc: Andy Lutomirski <luto@kernel.org> Cc: Christian Brauner <christian.brauner@ubuntu.com> Cc: Florian Weimer <fweimer@redhat.com> Cc: Jan Engelhardt <jengelh@inai.de> Cc: Tim Murray <timmurray@google.com> Cc: Jason Gunthorpe <jgg@nvidia.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* | mm: move anon_vma declarations to linux/mm_inline.hArnd Bergmann2022-01-151-0/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The patch to add anonymous vma names causes a build failure in some configurations: include/linux/mm_types.h: In function 'is_same_vma_anon_name': include/linux/mm_types.h:924:37: error: implicit declaration of function 'strcmp' [-Werror=implicit-function-declaration] 924 | return name && vma_name && !strcmp(name, vma_name); | ^~~~~~ include/linux/mm_types.h:22:1: note: 'strcmp' is defined in header '<string.h>'; did you forget to '#include <string.h>'? This should not really be part of linux/mm_types.h in the first place, as that header is meant to only contain structure defintions and need a minimum set of indirect includes itself. While the header clearly includes more than it should at this point, let's not make it worse by including string.h as well, which would pull in the expensive (compile-speed wise) fortify-string logic. Move the new functions into a separate header that only needs to be included in a couple of locations. Link: https://lkml.kernel.org/r/20211207125710.2503446-1-arnd@kernel.org Fixes: "mm: add a field to store names for private anonymous memory" Signed-off-by: Arnd Bergmann <arnd@arndb.de> Cc: Al Viro <viro@zeniv.linux.org.uk> Cc: Colin Cross <ccross@google.com> Cc: Eric Biederman <ebiederm@xmission.com> Cc: Kees Cook <keescook@chromium.org> Cc: Matthew Wilcox (Oracle) <willy@infradead.org> Cc: Peter Xu <peterx@redhat.com> Cc: Peter Zijlstra (Intel) <peterz@infradead.org> Cc: Stephen Rothwell <sfr@canb.auug.org.au> Cc: Suren Baghdasaryan <surenb@google.com> Cc: Vlastimil Babka <vbabka@suse.cz> Cc: Yu Zhao <yuzhao@google.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* | mm: add a field to store names for private anonymous memoryColin Cross2022-01-151-16/+22
|/ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | In many userspace applications, and especially in VM based applications like Android uses heavily, there are multiple different allocators in use. At a minimum there is libc malloc and the stack, and in many cases there are libc malloc, the stack, direct syscalls to mmap anonymous memory, and multiple VM heaps (one for small objects, one for big objects, etc.). Each of these layers usually has its own tools to inspect its usage; malloc by compiling a debug version, the VM through heap inspection tools, and for direct syscalls there is usually no way to track them. On Android we heavily use a set of tools that use an extended version of the logic covered in Documentation/vm/pagemap.txt to walk all pages mapped in userspace and slice their usage by process, shared (COW) vs. unique mappings, backing, etc. This can account for real physical memory usage even in cases like fork without exec (which Android uses heavily to share as many private COW pages as possible between processes), Kernel SamePage Merging, and clean zero pages. It produces a measurement of the pages that only exist in that process (USS, for unique), and a measurement of the physical memory usage of that process with the cost of shared pages being evenly split between processes that share them (PSS). If all anonymous memory is indistinguishable then figuring out the real physical memory usage (PSS) of each heap requires either a pagemap walking tool that can understand the heap debugging of every layer, or for every layer's heap debugging tools to implement the pagemap walking logic, in which case it is hard to get a consistent view of memory across the whole system. Tracking the information in userspace leads to all sorts of problems. It either needs to be stored inside the process, which means every process has to have an API to export its current heap information upon request, or it has to be stored externally in a filesystem that somebody needs to clean up on crashes. It needs to be readable while the process is still running, so it has to have some sort of synchronization with every layer of userspace. Efficiently tracking the ranges requires reimplementing something like the kernel vma trees, and linking to it from every layer of userspace. It requires more memory, more syscalls, more runtime cost, and more complexity to separately track regions that the kernel is already tracking. This patch adds a field to /proc/pid/maps and /proc/pid/smaps to show a userspace-provided name for anonymous vmas. The names of named anonymous vmas are shown in /proc/pid/maps and /proc/pid/smaps as [anon:<name>]. Userspace can set the name for a region of memory by calling prctl(PR_SET_VMA, PR_SET_VMA_ANON_NAME, start, len, (unsigned long)name) Setting the name to NULL clears it. The name length limit is 80 bytes including NUL-terminator and is checked to contain only printable ascii characters (including space), except '[',']','\','$' and '`'. Ascii strings are being used to have a descriptive identifiers for vmas, which can be understood by the users reading /proc/pid/maps or /proc/pid/smaps. Names can be standardized for a given system and they can include some variable parts such as the name of the allocator or a library, tid of the thread using it, etc. The name is stored in a pointer in the shared union in vm_area_struct that points to a null terminated string. Anonymous vmas with the same name (equivalent strings) and are otherwise mergeable will be merged. The name pointers are not shared between vmas even if they contain the same name. The name pointer is stored in a union with fields that are only used on file-backed mappings, so it does not increase memory usage. CONFIG_ANON_VMA_NAME kernel configuration is introduced to enable this feature. It keeps the feature disabled by default to prevent any additional memory overhead and to avoid confusing procfs parsers on systems which are not ready to support named anonymous vmas. The patch is based on the original patch developed by Colin Cross, more specifically on its latest version [1] posted upstream by Sumit Semwal. It used a userspace pointer to store vma names. In that design, name pointers could be shared between vmas. However during the last upstreaming attempt, Kees Cook raised concerns [2] about this approach and suggested to copy the name into kernel memory space, perform validity checks [3] and store as a string referenced from vm_area_struct. One big concern is about fork() performance which would need to strdup anonymous vma names. Dave Hansen suggested experimenting with worst-case scenario of forking a process with 64k vmas having longest possible names [4]. I ran this experiment on an ARM64 Android device and recorded a worst-case regression of almost 40% when forking such a process. This regression is addressed in the followup patch which replaces the pointer to a name with a refcounted structure that allows sharing the name pointer between vmas of the same name. Instead of duplicating the string during fork() or when splitting a vma it increments the refcount. [1] https://lore.kernel.org/linux-mm/20200901161459.11772-4-sumit.semwal@linaro.org/ [2] https://lore.kernel.org/linux-mm/202009031031.D32EF57ED@keescook/ [3] https://lore.kernel.org/linux-mm/202009031022.3834F692@keescook/ [4] https://lore.kernel.org/linux-mm/5d0358ab-8c47-2f5f-8e43-23b89d6a8e95@intel.com/ Changes for prctl(2) manual page (in the options section): PR_SET_VMA Sets an attribute specified in arg2 for virtual memory areas starting from the address specified in arg3 and spanning the size specified in arg4. arg5 specifies the value of the attribute to be set. Note that assigning an attribute to a virtual memory area might prevent it from being merged with adjacent virtual memory areas due to the difference in that attribute's value. Currently, arg2 must be one of: PR_SET_VMA_ANON_NAME Set a name for anonymous virtual memory areas. arg5 should be a pointer to a null-terminated string containing the name. The name length including null byte cannot exceed 80 bytes. If arg5 is NULL, the name of the appropriate anonymous virtual memory areas will be reset. The name can contain only printable ascii characters (including space), except '[',']','\','$' and '`'. This feature is available only if the kernel is built with the CONFIG_ANON_VMA_NAME option enabled. [surenb@google.com: docs: proc.rst: /proc/PID/maps: fix malformed table] Link: https://lkml.kernel.org/r/20211123185928.2513763-1-surenb@google.com [surenb: rebased over v5.15-rc6, replaced userpointer with a kernel copy, added input sanitization and CONFIG_ANON_VMA_NAME config. The bulk of the work here was done by Colin Cross, therefore, with his permission, keeping him as the author] Link: https://lkml.kernel.org/r/20211019215511.3771969-2-surenb@google.com Signed-off-by: Colin Cross <ccross@google.com> Signed-off-by: Suren Baghdasaryan <surenb@google.com> Reviewed-by: Kees Cook <keescook@chromium.org> Cc: Stephen Rothwell <sfr@canb.auug.org.au> Cc: Al Viro <viro@zeniv.linux.org.uk> Cc: Cyrill Gorcunov <gorcunov@openvz.org> Cc: Dave Hansen <dave.hansen@intel.com> Cc: David Rientjes <rientjes@google.com> Cc: "Eric W. Biederman" <ebiederm@xmission.com> Cc: Hugh Dickins <hughd@google.com> Cc: Ingo Molnar <mingo@kernel.org> Cc: Jan Glauber <jan.glauber@gmail.com> Cc: Johannes Weiner <hannes@cmpxchg.org> Cc: John Stultz <john.stultz@linaro.org> Cc: Mel Gorman <mgorman@suse.de> Cc: Minchan Kim <minchan@kernel.org> Cc: Oleg Nesterov <oleg@redhat.com> Cc: Pekka Enberg <penberg@kernel.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Rob Landley <rob@landley.net> Cc: "Serge E. Hallyn" <serge.hallyn@ubuntu.com> Cc: Shaohua Li <shli@fusionio.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* mm,hugetlb: remove mlock ulimit for SHM_HUGETLBzhangyiru2021-11-091-2/+1
| | | | | | | | | | | | | | | | | | | | | | Commit 21a3c273f88c ("mm, hugetlb: add thread name and pid to SHM_HUGETLB mlock rlimit warning") marked this as deprecated in 2012, but it is not deleted yet. Mike says he still sees that message in log files on occasion, so maybe we should preserve this warning. Also remove hugetlbfs related user_shm_unlock in ipc/shm.c and remove the user_shm_unlock after out. Link: https://lkml.kernel.org/r/20211103105857.25041-1-zhangyiru3@huawei.com Signed-off-by: zhangyiru <zhangyiru3@huawei.com> Reviewed-by: Mike Kravetz <mike.kravetz@oracle.com> Cc: Hugh Dickins <hughd@google.com> Cc: Liu Zixian <liuzixian4@huawei.com> Cc: Michal Hocko <mhocko@suse.com> Cc: wuxu.wu <wuxu.wu@huawei.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* mm/mmap.c: fix a data race of mm->total_vmPeng Liu2021-11-061-1/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The variable mm->total_vm could be accessed concurrently during mmaping and system accounting as noticed by KCSAN, BUG: KCSAN: data-race in __acct_update_integrals / mmap_region read-write to 0xffffa40267bd14c8 of 8 bytes by task 15609 on cpu 3: mmap_region+0x6dc/0x1400 do_mmap+0x794/0xca0 vm_mmap_pgoff+0xdf/0x150 ksys_mmap_pgoff+0xe1/0x380 do_syscall_64+0x37/0x50 entry_SYSCALL_64_after_hwframe+0x44/0xa9 read to 0xffffa40267bd14c8 of 8 bytes by interrupt on cpu 2: __acct_update_integrals+0x187/0x1d0 acct_account_cputime+0x3c/0x40 update_process_times+0x5c/0x150 tick_sched_timer+0x184/0x210 __run_hrtimer+0x119/0x3b0 hrtimer_interrupt+0x350/0xaa0 __sysvec_apic_timer_interrupt+0x7b/0x220 asm_call_irq_on_stack+0x12/0x20 sysvec_apic_timer_interrupt+0x4d/0x80 asm_sysvec_apic_timer_interrupt+0x12/0x20 smp_call_function_single+0x192/0x2b0 perf_install_in_context+0x29b/0x4a0 __se_sys_perf_event_open+0x1a98/0x2550 __x64_sys_perf_event_open+0x63/0x70 do_syscall_64+0x37/0x50 entry_SYSCALL_64_after_hwframe+0x44/0xa9 Reported by Kernel Concurrency Sanitizer on: CPU: 2 PID: 15610 Comm: syz-executor.3 Not tainted 5.10.0+ #2 Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS Ubuntu-1.8.2-1ubuntu1 04/01/2014 In vm_stat_account which called by mmap_region, increase total_vm, and __acct_update_integrals may read total_vm at the same time. This will cause a data race which lead to undefined behaviour. To avoid potential bad read/write, volatile property and barrier are both used to avoid undefined behaviour. Link: https://lkml.kernel.org/r/20210913105550.1569419-1-liupeng256@huawei.com Signed-off-by: Peng Liu <liupeng256@huawei.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* Merge tag 'denywrite-for-5.15' of git://github.com/davidhildenbrand/linuxLinus Torvalds2021-09-041-26/+3
|\ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Pull MAP_DENYWRITE removal from David Hildenbrand: "Remove all in-tree usage of MAP_DENYWRITE from the kernel and remove VM_DENYWRITE. There are some (minor) user-visible changes: - We no longer deny write access to shared libaries loaded via legacy uselib(); this behavior matches modern user space e.g. dlopen(). - We no longer deny write access to the elf interpreter after exec completed, treating it just like shared libraries (which it often is). - We always deny write access to the file linked via /proc/pid/exe: sys_prctl(PR_SET_MM_MAP/EXE_FILE) will fail if write access to the file cannot be denied, and write access to the file will remain denied until the link is effectivel gone (exec, termination, sys_prctl(PR_SET_MM_MAP/EXE_FILE)) -- just as if exec'ing the file. Cross-compiled for a bunch of architectures (alpha, microblaze, i386, s390x, ...) and verified via ltp that especially the relevant tests (i.e., creat07 and execve04) continue working as expected" * tag 'denywrite-for-5.15' of git://github.com/davidhildenbrand/linux: fs: update documentation of get_write_access() and friends mm: ignore MAP_DENYWRITE in ksys_mmap_pgoff() mm: remove VM_DENYWRITE binfmt: remove in-tree usage of MAP_DENYWRITE kernel/fork: always deny write access to current MM exe_file kernel/fork: factor out replacing the current MM exe_file binfmt: don't use MAP_DENYWRITE when loading shared libraries via uselib()
| * mm: ignore MAP_DENYWRITE in ksys_mmap_pgoff()David Hildenbrand2021-09-031-2/+0
| | | | | | | | | | | | | | | | | | | | | | | | | | Let's also remove masking off MAP_DENYWRITE from ksys_mmap_pgoff(): the last in-tree occurrence of MAP_DENYWRITE is now in LEGACY_MAP_MASK, which accepts the flag e.g., for MAP_SHARED_VALIDATE; however, the flag is ignored throughout the kernel now. Add a comment to LEGACY_MAP_MASK stating that MAP_DENYWRITE is ignored. Acked-by: "Eric W. Biederman" <ebiederm@xmission.com> Acked-by: Christian König <christian.koenig@amd.com> Signed-off-by: David Hildenbrand <david@redhat.com>
| * mm: remove VM_DENYWRITEDavid Hildenbrand2021-09-031-24/+3
| | | | | | | | | | | | | | | | | | All in-tree users of MAP_DENYWRITE are gone. MAP_DENYWRITE cannot be set from user space, so all users are gone; let's remove it. Acked-by: "Eric W. Biederman" <ebiederm@xmission.com> Acked-by: Christian König <christian.koenig@amd.com> Signed-off-by: David Hildenbrand <david@redhat.com>
* | Merge branch 'akpm' (patches from Andrew)Linus Torvalds2021-09-031-4/+3
|\ \ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Merge misc updates from Andrew Morton: "173 patches. Subsystems affected by this series: ia64, ocfs2, block, and mm (debug, pagecache, gup, swap, shmem, memcg, selftests, pagemap, mremap, bootmem, sparsemem, vmalloc, kasan, pagealloc, memory-failure, hugetlb, userfaultfd, vmscan, compaction, mempolicy, memblock, oom-kill, migration, ksm, percpu, vmstat, and madvise)" * emailed patches from Andrew Morton <akpm@linux-foundation.org>: (173 commits) mm/madvise: add MADV_WILLNEED to process_madvise() mm/vmstat: remove unneeded return value mm/vmstat: simplify the array size calculation mm/vmstat: correct some wrong comments mm/percpu,c: remove obsolete comments of pcpu_chunk_populated() selftests: vm: add COW time test for KSM pages selftests: vm: add KSM merging time test mm: KSM: fix data type selftests: vm: add KSM merging across nodes test selftests: vm: add KSM zero page merging test selftests: vm: add KSM unmerge test selftests: vm: add KSM merge test mm/migrate: correct kernel-doc notation mm: wire up syscall process_mrelease mm: introduce process_mrelease system call memblock: make memblock_find_in_range method private mm/mempolicy.c: use in_task() in mempolicy_slab_node() mm/mempolicy: unify the create() func for bind/interleave/prefer-many policies mm/mempolicy: advertise new MPOL_PREFERRED_MANY mm/hugetlb: add support for mempolicy MPOL_PREFERRED_MANY ...
| * | remap_file_pages: Use vma_lookup() instead of find_vma()Liam R. Howlett2021-09-031-4/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Using vma_lookup() verifies the start address is contained in the found vma. This results in easier to read code. Link: https://lkml.kernel.org/r/20210817135234.1550204-1-Liam.Howlett@oracle.com Signed-off-by: Liam R. Howlett <Liam.Howlett@Oracle.com> Reviewed-by: David Hildenbrand <david@redhat.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
| * | mm/pagemap: add mmap_assert_locked() annotations to find_vma*()Luigi Rizzo2021-09-031-0/+2
| |/ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | find_vma() and variants need protection when used. This patch adds mmap_assert_lock() calls in the functions. To make sure the invariant is satisfied, we also need to add a mmap_read_lock() around the get_user_pages_remote() call in get_arg_page(). The lock is not strictly necessary because the mm has been newly created, but the extra cost is limited because the same mutex was also acquired shortly before in __bprm_mm_init(), so it is hot and uncontended. [penguin-kernel@i-love.sakura.ne.jp: TOMOYO needs the same protection which get_arg_page() needs] Link: https://lkml.kernel.org/r/58bb6bf7-a57e-8a40-e74b-39584b415152@i-love.sakura.ne.jp Link: https://lkml.kernel.org/r/20210731175341.3458608-1-lrizzo@google.com Signed-off-by: Luigi Rizzo <lrizzo@google.com> Cc: David Rientjes <rientjes@google.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* / fs: remove mandatory file locking supportJeff Layton2021-08-231-6/+0
|/ | | | | | | | | | | | | | | | | | We added CONFIG_MANDATORY_FILE_LOCKING in 2015, and soon after turned it off in Fedora and RHEL8. Several other distros have followed suit. I've heard of one problem in all that time: Someone migrated from an older distro that supported "-o mand" to one that didn't, and the host had a fstab entry with "mand" in it which broke on reboot. They didn't actually _use_ mandatory locking so they just removed the mount option and moved on. This patch rips out mandatory locking support wholesale from the kernel, along with the Kconfig option and the Documentation file. It also changes the mount code to ignore the "mand" mount option instead of erroring out, and to throw a big, ugly warning. Signed-off-by: Jeff Layton <jlayton@kernel.org>
* mmap: make mlock_future_check() globalMike Rapoport2021-07-081-3/+2
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Patch series "mm: introduce memfd_secret system call to create "secret" memory areas", v20. This is an implementation of "secret" mappings backed by a file descriptor. The file descriptor backing secret memory mappings is created using a dedicated memfd_secret system call The desired protection mode for the memory is configured using flags parameter of the system call. The mmap() of the file descriptor created with memfd_secret() will create a "secret" memory mapping. The pages in that mapping will be marked as not present in the direct map and will be present only in the page table of the owning mm. Although normally Linux userspace mappings are protected from other users, such secret mappings are useful for environments where a hostile tenant is trying to trick the kernel into giving them access to other tenants mappings. It's designed to provide the following protections: * Enhanced protection (in conjunction with all the other in-kernel attack prevention systems) against ROP attacks. Seceretmem makes "simple" ROP insufficient to perform exfiltration, which increases the required complexity of the attack. Along with other protections like the kernel stack size limit and address space layout randomization which make finding gadgets is really hard, absence of any in-kernel primitive for accessing secret memory means the one gadget ROP attack can't work. Since the only way to access secret memory is to reconstruct the missing mapping entry, the attacker has to recover the physical page and insert a PTE pointing to it in the kernel and then retrieve the contents. That takes at least three gadgets which is a level of difficulty beyond most standard attacks. * Prevent cross-process secret userspace memory exposures. Once the secret memory is allocated, the user can't accidentally pass it into the kernel to be transmitted somewhere. The secreremem pages cannot be accessed via the direct map and they are disallowed in GUP. * Harden against exploited kernel flaws. In order to access secretmem, a kernel-side attack would need to either walk the page tables and create new ones, or spawn a new privileged uiserspace process to perform secrets exfiltration using ptrace. In the future the secret mappings may be used as a mean to protect guest memory in a virtual machine host. For demonstration of secret memory usage we've created a userspace library https://git.kernel.org/pub/scm/linux/kernel/git/jejb/secret-memory-preloader.git that does two things: the first is act as a preloader for openssl to redirect all the OPENSSL_malloc calls to secret memory meaning any secret keys get automatically protected this way and the other thing it does is expose the API to the user who needs it. We anticipate that a lot of the use cases would be like the openssl one: many toolkits that deal with secret keys already have special handling for the memory to try to give them greater protection, so this would simply be pluggable into the toolkits without any need for user application modification. Hiding secret memory mappings behind an anonymous file allows usage of the page cache for tracking pages allocated for the "secret" mappings as well as using address_space_operations for e.g. page migration callbacks. The anonymous file may be also used implicitly, like hugetlb files, to implement mmap(MAP_SECRET) and use the secret memory areas with "native" mm ABIs in the future. Removing of the pages from the direct map may cause its fragmentation on architectures that use large pages to map the physical memory which affects the system performance. However, the original Kconfig text for CONFIG_DIRECT_GBPAGES said that gigabyte pages in the direct map "... can improve the kernel's performance a tiny bit ..." (commit 00d1c5e05736 ("x86: add gbpages switches")) and the recent report [1] showed that "... although 1G mappings are a good default choice, there is no compelling evidence that it must be the only choice". Hence, it is sufficient to have secretmem disabled by default with the ability of a system administrator to enable it at boot time. In addition, there is also a long term goal to improve management of the direct map. [1] https://lore.kernel.org/linux-mm/213b4567-46ce-f116-9cdf-bbd0c884eb3c@linux.intel.com/ This patch (of 7): It will be used by the upcoming secret memory implementation. Link: https://lkml.kernel.org/r/20210518072034.31572-1-rppt@kernel.org Link: https://lkml.kernel.org/r/20210518072034.31572-2-rppt@kernel.org Signed-off-by: Mike Rapoport <rppt@linux.ibm.com> Reviewed-by: David Hildenbrand <david@redhat.com> Acked-by: James Bottomley <James.Bottomley@HansenPartnership.com> Cc: Alexander Viro <viro@zeniv.linux.org.uk> Cc: Andy Lutomirski <luto@kernel.org> Cc: Arnd Bergmann <arnd@arndb.de> Cc: Borislav Petkov <bp@alien8.de> Cc: Catalin Marinas <catalin.marinas@arm.com> Cc: Christopher Lameter <cl@linux.com> Cc: Dan Williams <dan.j.williams@intel.com> Cc: Dave Hansen <dave.hansen@linux.intel.com> Cc: David Hildenbrand <david@redhat.com> Cc: Elena Reshetova <elena.reshetova@intel.com> Cc: Hagen Paul Pfeifer <hagen@jauu.net> Cc: "H. Peter Anvin" <hpa@zytor.com> Cc: Ingo Molnar <mingo@redhat.com> Cc: James Bottomley <jejb@linux.ibm.com> Cc: "Kirill A. Shutemov" <kirill@shutemov.name> Cc: Mark Rutland <mark.rutland@arm.com> Cc: Matthew Wilcox <willy@infradead.org> Cc: Michael Kerrisk <mtk.manpages@gmail.com> Cc: Palmer Dabbelt <palmer@dabbelt.com> Cc: Palmer Dabbelt <palmerdabbelt@google.com> Cc: Paul Walmsley <paul.walmsley@sifive.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Rick Edgecombe <rick.p.edgecombe@intel.com> Cc: Roman Gushchin <guro@fb.com> Cc: Shakeel Butt <shakeelb@google.com> Cc: Shuah Khan <shuah@kernel.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Tycho Andersen <tycho@tycho.ws> Cc: Will Deacon <will@kernel.org> Cc: kernel test robot <lkp@intel.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* Merge branch 'akpm' (patches from Andrew)Linus Torvalds2021-06-291-30/+24
|\ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Merge misc updates from Andrew Morton: "191 patches. Subsystems affected by this patch series: kthread, ia64, scripts, ntfs, squashfs, ocfs2, kernel/watchdog, and mm (gup, pagealloc, slab, slub, kmemleak, dax, debug, pagecache, gup, swap, memcg, pagemap, mprotect, bootmem, dma, tracing, vmalloc, kasan, initialization, pagealloc, and memory-failure)" * emailed patches from Andrew Morton <akpm@linux-foundation.org>: (191 commits) mm,hwpoison: make get_hwpoison_page() call get_any_page() mm,hwpoison: send SIGBUS with error virutal address mm/page_alloc: split pcp->high across all online CPUs for cpuless nodes mm/page_alloc: allow high-order pages to be stored on the per-cpu lists mm: replace CONFIG_FLAT_NODE_MEM_MAP with CONFIG_FLATMEM mm: replace CONFIG_NEED_MULTIPLE_NODES with CONFIG_NUMA docs: remove description of DISCONTIGMEM arch, mm: remove stale mentions of DISCONIGMEM mm: remove CONFIG_DISCONTIGMEM m68k: remove support for DISCONTIGMEM arc: remove support for DISCONTIGMEM arc: update comment about HIGHMEM implementation alpha: remove DISCONTIGMEM and NUMA mm/page_alloc: move free_the_page mm/page_alloc: fix counting of managed_pages mm/page_alloc: improve memmap_pages dbg msg mm: drop SECTION_SHIFT in code comments mm/page_alloc: introduce vm.percpu_pagelist_high_fraction mm/page_alloc: limit the number of pages on PCP lists when reclaim is active mm/page_alloc: scale the number of pages that are batch freed ...
| * mm/mmap: use find_vma_intersection() in do_mmap() for overlapLiam Howlett2021-06-291-3/+1
| | | | | | | | | | | | | | | | | | | | | | Using find_vma_intersection() avoids the need for a temporary variable and makes the code cleaner. Link: https://lkml.kernel.org/r/20210511014328.2902782-1-Liam.Howlett@Oracle.com Signed-off-by: Liam R. Howlett <Liam.Howlett@Oracle.com> Reviewed-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
| * mm/mmap: introduce unlock_range() for code cleanupLiam Howlett2021-06-291-19/+20
| | | | | | | | | | | | | | | | | | | | | | | | | | | | Both __do_munmap() and exit_mmap() unlock a range of VMAs using almost identical code blocks. Replace both blocks by a static inline function. [akpm@linux-foundation.org: tweak code layout] Link: https://lkml.kernel.org/r/20210510211021.2797427-1-Liam.Howlett@Oracle.com Signed-off-by: Liam R. Howlett <Liam.Howlett@Oracle.com> Reviewed-by: Matthew Wilcox (Oracle) <willy@infradead.org> Reviewed-by: Davidlohr Bueso <dbueso@suse.de> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
| * mm/mmap.c: logic of find_vma_intersection repeated in __do_munmapGonzalo Matias Juarez Tello2021-06-291-7/+2
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Logic of find_vma_intersection() is repeated in __do_munmap(). Also, prev is assigned a value before checking vma->vm_start >= end which might end up on a return statement making that assignment useless. Calling find_vma_intersection() checks that condition and returns NULL if no vma is found, hence only the !vma check is needed in __do_munmap(). Link: https://lkml.kernel.org/r/20210409162129.18313-1-gmjuareztello@gmail.com Signed-off-by: Gonzalo Matias Juarez Tello <gmjuareztello@gmail.com> Reviewed-by: Andrew Morton <akpm@linux-foundation.org> Reviewed-by: David Hildenbrand <david@redhat.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
| * mm: ignore MAP_EXECUTABLE in ksys_mmap_pgoff()David Hildenbrand2021-06-291-1/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Let's also remove masking off MAP_EXECUTABLE from ksys_mmap_pgoff(): the last in-tree occurrence of MAP_EXECUTABLE is now in LEGACY_MAP_MASK, which accepts the flag e.g., for MAP_SHARED_VALIDATE; however, the flag is ignored throughout the kernel now. Add a comment to LEGACY_MAP_MASK stating that MAP_EXECUTABLE is ignored. Link: https://lkml.kernel.org/r/20210421093453.6904-4-david@redhat.com Signed-off-by: David Hildenbrand <david@redhat.com> Acked-by: "Eric W. Biederman" <ebiederm@xmission.com> Reviewed-by: Kees Cook <keescook@chromium.org> Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com> Cc: Alexander Viro <viro@zeniv.linux.org.uk> Cc: Arnaldo Carvalho de Melo <acme@kernel.org> Cc: Borislav Petkov <bp@alien8.de> Cc: Catalin Marinas <catalin.marinas@arm.com> Cc: Don Zickus <dzickus@redhat.com> Cc: Feng Tang <feng.tang@intel.com> Cc: Greg Ungerer <gerg@linux-m68k.org> Cc: "H. Peter Anvin" <hpa@zytor.com> Cc: Ingo Molnar <mingo@redhat.com> Cc: Jiri Olsa <jolsa@redhat.com> Cc: Kevin Brodsky <Kevin.Brodsky@arm.com> Cc: Mark Rutland <mark.rutland@arm.com> Cc: Michal Hocko <mhocko@suse.com> Cc: Mike Rapoport <rppt@kernel.org> Cc: Namhyung Kim <namhyung@kernel.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* | Merge branch 'for-linus' of ↵Linus Torvalds2021-06-281-2/+2
|\ \ | |/ |/| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/ebiederm/user-namespace Pull user namespace rlimit handling update from Eric Biederman: "This is the work mainly by Alexey Gladkov to limit rlimits to the rlimits of the user that created a user namespace, and to allow users to have stricter limits on the resources created within a user namespace." * 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/ebiederm/user-namespace: cred: add missing return error code when set_cred_ucounts() failed ucounts: Silence warning in dec_rlimit_ucounts ucounts: Set ucount_max to the largest positive value the type can hold kselftests: Add test to check for rlimit changes in different user namespaces Reimplement RLIMIT_MEMLOCK on top of ucounts Reimplement RLIMIT_SIGPENDING on top of ucounts Reimplement RLIMIT_MSGQUEUE on top of ucounts Reimplement RLIMIT_NPROC on top of ucounts Use atomic_t for ucounts reference counting Add a reference to ucounts for each cred Increase size of ucounts to atomic_long_t
| * Reimplement RLIMIT_MEMLOCK on top of ucountsAlexey Gladkov2021-04-301-2/+2
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The rlimit counter is tied to uid in the user_namespace. This allows rlimit values to be specified in userns even if they are already globally exceeded by the user. However, the value of the previous user_namespaces cannot be exceeded. Changelog v11: * Fix issue found by lkp robot. v8: * Fix issues found by lkp-tests project. v7: * Keep only ucounts for RLIMIT_MEMLOCK checks instead of struct cred. v6: * Fix bug in hugetlb_file_setup() detected by trinity. Reported-by: kernel test robot <oliver.sang@intel.com> Reported-by: kernel test robot <lkp@intel.com> Signed-off-by: Alexey Gladkov <legion@kernel.org> Link: https://lkml.kernel.org/r/970d50c70c71bfd4496e0e8d2a0a32feebebb350.1619094428.git.legion@kernel.org Signed-off-by: Eric W. Biederman <ebiederm@xmission.com>
* | mm: fix typos in commentsIngo Molnar2021-05-071-2/+2
| | | | | | | | | | | | | | | | | | | | | | | | | | | | Fix ~94 single-word typos in locking code comments, plus a few very obvious grammar mistakes. Link: https://lkml.kernel.org/r/20210322212624.GA1963421@gmail.com Link: https://lore.kernel.org/r/20210322205203.GB1959563@gmail.com Signed-off-by: Ingo Molnar <mingo@kernel.org> Reviewed-by: Matthew Wilcox (Oracle) <willy@infradead.org> Reviewed-by: Randy Dunlap <rdunlap@infradead.org> Cc: Bhaskar Chowdhury <unixbhaskar@gmail.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* | mm/mmap.c: don't unlock VMAs in remap_file_pages()Liam Howlett2021-05-051-17/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | Since this call uses MAP_FIXED, do_mmap() will munlock the necessary range. There is also an error in the loop test expression which will evaluate as false and the loop body has never execute. Link: https://lkml.kernel.org/r/20210223235010.2296915-1-Liam.Howlett@Oracle.com Signed-off-by: Liam R. Howlett <Liam.Howlett@Oracle.com> Acked-by: Hugh Dickins <hughd@google.com> Reviewed-by: Matthew Wilcox (Oracle) <willy@infradead.org> Reviewed-by: David Hildenbrand <david@redhat.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* | Revert "mremap: don't allow MREMAP_DONTUNMAP on special_mappings and aio"Brian Geffon2021-04-301-5/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | This reverts commit cd544fd1dc9293c6702fab6effa63dac1cc67e99. As discussed in [1] this commit was a no-op because the mapping type was checked in vma_to_resize before move_vma is ever called. This meant that vm_ops->mremap() would never be called on such mappings. Furthermore, we've since expanded support of MREMAP_DONTUNMAP to non-anonymous mappings, and these special mappings are still protected by the existing check of !VM_DONTEXPAND and !VM_PFNMAP which will result in a -EINVAL. 1. https://lkml.org/lkml/2020/12/28/2340 Link: https://lkml.kernel.org/r/20210323182520.2712101-2-bgeffon@google.com Signed-off-by: Brian Geffon <bgeffon@google.com> Acked-by: Hugh Dickins <hughd@google.com> Reviewed-by: Dmitry Safonov <0x7f454c46@gmail.com> Cc: Alejandro Colomar <alx.manpages@gmail.com> Cc: Andrea Arcangeli <aarcange@redhat.com> Cc: Andy Lutomirski <luto@amacapital.net> Cc: Axel Rasmussen <axelrasmussen@google.com> Cc: "Kirill A . Shutemov" <kirill@shutemov.name> Cc: Lokesh Gidra <lokeshgidra@google.com> Cc: Michael Kerrisk <mtk.manpages@gmail.com> Cc: "Michael S . Tsirkin" <mst@redhat.com> Cc: Mike Rapoport <rppt@linux.vnet.ibm.com> Cc: Minchan Kim <minchan@kernel.org> Cc: Peter Xu <peterx@redhat.com> Cc: Sonny Rao <sonnyrao@google.com> Cc: Vlastimil Babka <vbabka@suse.cz> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* | arm64: Support execute-only permissions with Enhanced PANVladimir Murzin2021-03-261-0/+6
|/ | | | | | | | | | | | | | | Enhanced Privileged Access Never (EPAN) allows Privileged Access Never to be used with Execute-only mappings. Absence of such support was a reason for 24cecc377463 ("arm64: Revert support for execute-only user mappings"). Thus now it can be revisited and re-enabled. Cc: Kees Cook <keescook@chromium.org> Signed-off-by: Vladimir Murzin <vladimir.murzin@arm.com> Acked-by: Will Deacon <will@kernel.org> Link: https://lore.kernel.org/r/20210312173811.58284-2-vladimir.murzin@arm.com Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
* mm/mmap.c: remove unnecessary local variableAdrian Huang2021-02-241-3/+1
| | | | | | | | | | | | | The local variable 'retval' is assigned just for once in __do_sys_brk(), and the function returns the value of the local variable right after the assignment. Remove unnecessary assignment and local variable declaration. Link: https://lkml.kernel.org/r/20201222103249.30683-1-adrianhuang0701@gmail.com Signed-off-by: Adrian Huang <ahuang12@lenovo.com> Acked-by: Souptick Joarder <jrdr.linux@gmail.com> Reviewed-by: David Hildenbrand <david@redhat.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* tlb: mmu_gather: Remove start/end arguments from tlb_gather_mmu()Will Deacon2021-01-291-1/+1
| | | | | | | | | | | | | | | The 'start' and 'end' arguments to tlb_gather_mmu() are no longer needed now that there is a separate function for 'fullmm' flushing. Remove the unused arguments and update all callers. Suggested-by: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Will Deacon <will@kernel.org> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Reviewed-by: Yu Zhao <yuzhao@google.com> Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org> Acked-by: Linus Torvalds <torvalds@linux-foundation.org> Link: https://lore.kernel.org/r/CAHk-=wjQWa14_4UpfDf=fiineNP+RH74kZeDMo_f1D35xNzq9w@mail.gmail.com
* tlb: mmu_gather: Introduce tlb_gather_mmu_fullmm()Will Deacon2021-01-291-1/+1
| | | | | | | | | | | | | | | | | | | | Passing the range '0, -1' to tlb_gather_mmu() sets the 'fullmm' flag, which indicates that the mm_struct being operated on is going away. In this case, some architectures (such as arm64) can elide TLB invalidation by ensuring that the TLB tag (ASID) associated with this mm is not immediately reclaimed. Although this behaviour is documented in asm-generic/tlb.h, it's subtle and easily missed. Introduce tlb_gather_mmu_fullmm() to make it clearer that this is for the entire mm and WARN() if tlb_gather_mmu() is called with the 'fullmm' address range. Signed-off-by: Will Deacon <will@kernel.org> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Reviewed-by: Yu Zhao <yuzhao@google.com> Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org> Acked-by: Linus Torvalds <torvalds@linux-foundation.org> Link: https://lkml.kernel.org/r/20210127235347.1402-4-will@kernel.org
* tlb: mmu_gather: Remove unused start/end arguments from tlb_finish_mmu()Will Deacon2021-01-291-2/+2
| | | | | | | | | | | | | | | | Since commit 7a30df49f63a ("mm: mmu_gather: remove __tlb_reset_range() for force flush"), the 'start' and 'end' arguments to tlb_finish_mmu() are no longer used, since we flush the whole mm in case of a nested invalidation. Remove the unused arguments and update all callers. Signed-off-by: Will Deacon <will@kernel.org> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Reviewed-by: Yu Zhao <yuzhao@google.com> Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org> Acked-by: Linus Torvalds <torvalds@linux-foundation.org> Link: https://lkml.kernel.org/r/20210127235347.1402-3-will@kernel.org
* Merge tag 'drm-next-2020-12-18' of git://anongit.freedesktop.org/drm/drmLinus Torvalds2020-12-181-1/+1
|\ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Pull more drm updates from Daniel Vetter: "UAPI Changes: - Only enable char/agp uapi when CONFIG_DRM_LEGACY is set Cross-subsystem Changes: - vma_set_file helper to make vma->vm_file changing less brittle, acked by Andrew Core Changes: - dma-buf heaps improvements - pass full atomic modeset state to driver callbacks - shmem helpers: cached bo by default - cleanups for fbdev, fb-helpers - better docs for drm modes and SCALING_FITLER uapi - ttm: fix dma32 page pool regression Driver Changes: - multi-hop regression fixes for amdgpu, radeon, nouveau - lots of small amdgpu hw enabling fixes (display, pm, ...) - fixes for imx, mcde, meson, some panels, virtio, qxl, i915, all fairly minor - some cleanups for legacy drm/fbdev drivers" * tag 'drm-next-2020-12-18' of git://anongit.freedesktop.org/drm/drm: (117 commits) drm/qxl: don't allocate a dma_address array drm/nouveau: fix multihop when move doesn't work. drm/i915/tgl: Fix REVID macros for TGL to fetch correct stepping drm/i915: Fix mismatch between misplaced vma check and vma insert drm/i915/perf: also include Gen11 in OATAILPTR workaround Revert "drm/i915: re-order if/else ladder for hpd_irq_setup" drm/amdgpu/disply: fix documentation warnings in display manager drm/amdgpu: print mmhub client name for dimgrey_cavefish drm/amdgpu: set mode1 reset as default for dimgrey_cavefish drm/amd/display: Add get_dig_frontend implementation for DCEx drm/radeon: remove h from printk format specifier drm/amdgpu: remove h from printk format specifier drm/amdgpu: Fix spelling mistake "Heterogenous" -> "Heterogeneous" drm/amdgpu: fix regression in vbios reservation handling on headless drm/amdgpu/SRIOV: Extend VF reset request wait period drm/amdkfd: correct amdgpu_amdkfd_gpuvm_alloc_memory_of_gpu log. drm/amd/display: Adding prototype for dccg21_update_dpp_dto() drm/amdgpu: print what method we are using for runtime pm drm/amdgpu: simplify logic in atpx resume handling drm/amdgpu: no need to call pci_ignore_hotplug for _PR3 ...
| * Merge tag 'drm-misc-next-2020-11-27-1' of ↵Daniel Vetter2020-12-151-1/+1
| |\ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://anongit.freedesktop.org/drm/drm-misc into drm-next drm-misc-next for 5.11: UAPI Changes: Cross-subsystem Changes: * char/agp: Disable frontend without CONFIG_DRM_LEGACY * mm: Fix fput in mmap error path; Introduce vma_set_file() to change vma->vm_file Core Changes: * dma-buf: Use sgtables in system heap; Move heap helpers to CMA-heap code; Skip sync for unmapped buffers; Alloc higher order pages is available; Respect num_fences when initializing shared fence list * doc: Improvements around DRM modes and SCALING_FILTER * Pass full state to connector atomic functions + callee updates * Cleanups * shmem: Map pages with caching by default; Cleanups * ttm: Fix DMA32 for global page pool * fbdev: Cleanups * fb-helper: Update framebuffer after userspace writes; Unmap console buffer during shutdown; Rework damage handling of shadow framebuffer Driver Changes: * amdgpu: Multi-hop fixes, Clenaups * imx: Fix rotation for Vivante tiled formats; Support nearest-neighour skaling; Cleanups * mcde: Fix RGB formats; Support DPI output; Cleanups * meson: HDMI clock fixes * panel: Add driver and bindings for Innolux N125HCE-GN1 * panel/s6e63m0: More backlight levels; Fix init; Cleanups * via: Clenunps * virtio: Use fence ID for handling fences; Cleanups Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch> From: Thomas Zimmermann <tzimmermann@suse.de> Link: https://patchwork.freedesktop.org/patch/msgid/20201127083055.GA29139@linux-uq9g
| | * mm: mmap: fix fput in error path v2Christian König2020-11-191-1/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Patch "495c10cc1c0c CHROMIUM: dma-buf: restore args..." adds a workaround for a bug in mmap_region. As the comment states ->mmap() callback can change vma->vm_file and so we might call fput() on the wrong file. Revert the workaround and proper fix this in mmap_region. v2: drop the extra if in dma_buf_mmap as well Signed-off-by: Christian König <christian.koenig@amd.com> Reviewed-by: Jason Gunthorpe <jgg@nvidia.com> Acked-by: Andrew Morton <akpm@linux-foundation.org> Link: https://patchwork.freedesktop.org/patch/399359/
| | * Revert "mm: mmap: fix fput in error path v2"Christian König2020-11-051-1/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The kernel test robot is not happy with that. This reverts commit 0227da01f2559626396af5f6c7453360db86c1f6. Signed-off-by: Christian König <christian.koenig@amd.com> Acked-by: Daniel Vetter <daniel@ffwll.ch> Link: https://patchwork.freedesktop.org/patch/394772/
| | * Revert "mm: introduce vma_set_file function v4"Christian König2020-11-051-12/+0
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The kernel test robot is not happy with that. This reverts commit 2b5b95b1ff3d70a95013a45e3b5b90f1daf42348. Signed-off-by: Christian König <christian.koenig@amd.com> Acked-by: Daniel Vetter <daniel@ffwll.ch> Link: https://patchwork.freedesktop.org/patch/394773/
| | * mm: introduce vma_set_file function v4Christian König2020-11-051-0/+12
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Add the new vma_set_file() function to allow changing vma->vm_file with the necessary refcount dance. v2: add more users of this. v3: add missing EXPORT_SYMBOL, rebase on mmap cleanup, add comments why we drop the reference on two occasions. v4: make it clear that changing an anonymous vma is illegal. Signed-off-by: Christian König <christian.koenig@amd.com> Reviewed-by: Daniel Vetter <daniel.vetter@ffwll.ch> (v2) Reviewed-by: Jason Gunthorpe <jgg@nvidia.com> Link: https://patchwork.freedesktop.org/patch/394773/
| | * mm: mmap: fix fput in error path v2Christian König2020-11-051-1/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Patch "495c10cc1c0c CHROMIUM: dma-buf: restore args..." adds a workaround for a bug in mmap_region. As the comment states ->mmap() callback can change vma->vm_file and so we might call fput() on the wrong file. Revert the workaround and proper fix this in mmap_region. v2: drop the extra if in dma_buf_mmap as well Signed-off-by: Christian König <christian.koenig@amd.com> Reviewed-by: Jason Gunthorpe <jgg@nvidia.com> Link: https://patchwork.freedesktop.org/patch/394772/
* | | mm: forbid splitting special mappingsDmitry Safonov2020-12-151-0/+12
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Don't allow splitting of vm_special_mapping's. It affects vdso/vvar areas. Uprobes have only one page in xol_area so they aren't affected. Those restrictions were enforced by checks in .mremap() callbacks. Restrict resizing with generic .split() callback. Link: https://lkml.kernel.org/r/20201013013416.390574-7-dima@arista.com Signed-off-by: Dmitry Safonov <dima@arista.com> Cc: Alexander Viro <viro@zeniv.linux.org.uk> Cc: Andy Lutomirski <luto@kernel.org> Cc: Brian Geffon <bgeffon@google.com> Cc: Catalin Marinas <catalin.marinas@arm.com> Cc: Dan Carpenter <dan.carpenter@oracle.com> Cc: Dan Williams <dan.j.williams@intel.com> Cc: Dave Jiang <dave.jiang@intel.com> Cc: Hugh Dickins <hughd@google.com> Cc: Ingo Molnar <mingo@redhat.com> Cc: Jason Gunthorpe <jgg@ziepe.ca> Cc: John Hubbard <jhubbard@nvidia.com> Cc: "Kirill A. Shutemov" <kirill.shutemov@linux.intel.com> Cc: Mike Kravetz <mike.kravetz@oracle.com> Cc: Minchan Kim <minchan@kernel.org> Cc: Ralph Campbell <rcampbell@nvidia.com> Cc: Russell King <linux@armlinux.org.uk> Cc: Thomas Bogendoerfer <tsbogend@alpha.franken.de> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Vishal Verma <vishal.l.verma@intel.com> Cc: Vlastimil Babka <vbabka@suse.cz> Cc: Will Deacon <will@kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* | | vm_ops: rename .split() callback to .may_split()Dmitry Safonov2020-12-151-2/+2
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Rename the callback to reflect that it's not called *on* or *after* split, but rather some time before the splitting to check if it's possible. Link: https://lkml.kernel.org/r/20201013013416.390574-5-dima@arista.com Signed-off-by: Dmitry Safonov <dima@arista.com> Cc: Alexander Viro <viro@zeniv.linux.org.uk> Cc: Andy Lutomirski <luto@kernel.org> Cc: Brian Geffon <bgeffon@google.com> Cc: Catalin Marinas <catalin.marinas@arm.com> Cc: Dan Carpenter <dan.carpenter@oracle.com> Cc: Dan Williams <dan.j.williams@intel.com> Cc: Dave Jiang <dave.jiang@intel.com> Cc: Hugh Dickins <hughd@google.com> Cc: Ingo Molnar <mingo@redhat.com> Cc: Jason Gunthorpe <jgg@ziepe.ca> Cc: John Hubbard <jhubbard@nvidia.com> Cc: "Kirill A. Shutemov" <kirill.shutemov@linux.intel.com> Cc: Mike Kravetz <mike.kravetz@oracle.com> Cc: Minchan Kim <minchan@kernel.org> Cc: Ralph Campbell <rcampbell@nvidia.com> Cc: Russell King <linux@armlinux.org.uk> Cc: Thomas Bogendoerfer <tsbogend@alpha.franken.de> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Vishal Verma <vishal.l.verma@intel.com> Cc: Vlastimil Babka <vbabka@suse.cz> Cc: Will Deacon <will@kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* | | mremap: don't allow MREMAP_DONTUNMAP on special_mappings and aioDmitry Safonov2020-12-151-1/+5
|/ / | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | As kernel expect to see only one of such mappings, any further operations on the VMA-copy may be unexpected by the kernel. Maybe it's being on the safe side, but there doesn't seem to be any expected use-case for this, so restrict it now. Link: https://lkml.kernel.org/r/20201013013416.390574-4-dima@arista.com Fixes: commit e346b3813067 ("mm/mremap: add MREMAP_DONTUNMAP to mremap()") Signed-off-by: Dmitry Safonov <dima@arista.com> Cc: Alexander Viro <viro@zeniv.linux.org.uk> Cc: Andy Lutomirski <luto@kernel.org> Cc: Brian Geffon <bgeffon@google.com> Cc: Catalin Marinas <catalin.marinas@arm.com> Cc: Dan Carpenter <dan.carpenter@oracle.com> Cc: Dan Williams <dan.j.williams@intel.com> Cc: Dave Jiang <dave.jiang@intel.com> Cc: Hugh Dickins <hughd@google.com> Cc: Ingo Molnar <mingo@redhat.com> Cc: Jason Gunthorpe <jgg@ziepe.ca> Cc: John Hubbard <jhubbard@nvidia.com> Cc: "Kirill A. Shutemov" <kirill.shutemov@linux.intel.com> Cc: Mike Kravetz <mike.kravetz@oracle.com> Cc: Minchan Kim <minchan@kernel.org> Cc: Ralph Campbell <rcampbell@nvidia.com> Cc: Russell King <linux@armlinux.org.uk> Cc: Thomas Bogendoerfer <tsbogend@alpha.franken.de> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Vishal Verma <vishal.l.verma@intel.com> Cc: Vlastimil Babka <vbabka@suse.cz> Cc: Will Deacon <will@kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* / mm/mmap.c: fix mmap return value when vma is merged after call_mmap()Liu Zixian2020-12-061-14/+12
|/ | | | | | | | | | | | | | | | | | | | | | | On success, mmap should return the begin address of newly mapped area, but patch "mm: mmap: merge vma after call_mmap() if possible" set vm_start of newly merged vma to return value addr. Users of mmap will get wrong address if vma is merged after call_mmap(). We fix this by moving the assignment to addr before merging vma. We have a driver which changes vm_flags, and this bug is found by our testcases. Fixes: d70cec898324 ("mm: mmap: merge vma after call_mmap() if possible") Signed-off-by: Liu Zixian <liuzixian4@huawei.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Reviewed-by: Jason Gunthorpe <jgg@nvidia.com> Reviewed-by: David Hildenbrand <david@redhat.com> Cc: Miaohe Lin <linmiaohe@huawei.com> Cc: Hongxiang Lou <louhongxiang@huawei.com> Cc: Hu Shiyuan <hushiyuan@huawei.com> Cc: Matthew Wilcox <willy@infradead.org> Link: https://lkml.kernel.org/r/20201203085350.22624-1-liuzixian4@huawei.com Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* mm/mmap: add inline munmap_vma_range() for code readabilityLiam R. Howlett2020-10-181-15/+33
| | | | | | | | | | | | | There are two locations that have a block of code for munmapping a vma range. Change those two locations to use a function and add meaningful comments about what happens to the arguments, which was unclear in the previous code. Signed-off-by: Liam R. Howlett <Liam.Howlett@Oracle.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Reviewed-by: Andrew Morton <akpm@linux-foundation.org> Link: http://lkml.kernel.org/r/20200818154707.2515169-2-Liam.Howlett@Oracle.com Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* mm/mmap: add inline vma_next() for readability of mmap codeLiam R. Howlett2020-10-181-6/+20
| | | | | | | | | | | | There are three places that the next vma is required which uses the same block of code. Replace the block with a function and add comments on what happens in the case where NULL is encountered. Signed-off-by: Liam R. Howlett <Liam.Howlett@Oracle.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Reviewed-by: Andrew Morton <akpm@linux-foundation.org> Link: http://lkml.kernel.org/r/20200818154707.2515169-1-Liam.Howlett@Oracle.com Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
generated by cgit v1.2.3 (git 2.25.1) at 2024-11-09 17:24:03 +0000