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2024-02-25Merge tag 'pull-fixes.pathwalk-rcu-2' of ↵Linus Torvalds3-14/+9
git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs Pull RCU pathwalk fixes from Al Viro: "We still have some races in filesystem methods when exposed to RCU pathwalk. This series is a result of code audit (the second round of it) and it should deal with most of that stuff. Still pending: ntfs3 ->d_hash()/->d_compare() and ceph_d_revalidate(). Up to maintainers (a note for NTFS folks - when documentation says that a method may not block, it *does* imply that blocking allocations are to be avoided. Really)" [ More explanations for people who aren't familiar with the vagaries of RCU path walking: most of it is hidden from filesystems, but if a filesystem actively participates in the low-level path walking it needs to make sure the fields involved in that walk are RCU-safe. That "actively participate in low-level path walking" includes things like having its own ->d_hash()/->d_compare() routines, or by having its own directory permission function that doesn't just use the common helpers. Having a ->d_revalidate() function will also have this issue. Note that instead of making everything RCU safe you can also choose to abort the RCU pathwalk if your operation cannot be done safely under RCU, but that obviously comes with a performance penalty. One common pattern is to allow the simple cases under RCU, and abort only if you need to do something more complicated. So not everything needs to be RCU-safe, and things like the inode etc that the VFS itself maintains obviously already are. But these fixes tend to be about properly RCU-delaying things like ->s_fs_info that are maintained by the filesystem and that got potentially released too early. - Linus ] * tag 'pull-fixes.pathwalk-rcu-2' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs: ext4_get_link(): fix breakage in RCU mode cifs_get_link(): bail out in unsafe case fuse: fix UAF in rcu pathwalks procfs: make freeing proc_fs_info rcu-delayed procfs: move dropping pde and pid from ->evict_inode() to ->free_inode() nfs: fix UAF on pathwalk running into umount nfs: make nfs_set_verifier() safe for use in RCU pathwalk afs: fix __afs_break_callback() / afs_drop_open_mmap() race hfsplus: switch to rcu-delayed unloading of nls and freeing ->s_fs_info exfat: move freeing sbi, upcase table and dropping nls into rcu-delayed helper affs: free affs_sb_info with kfree_rcu() rcu pathwalk: prevent bogus hard errors from may_lookup() fs/super.c: don't drop ->s_user_ns until we free struct super_block itself
2024-02-25procfs: make freeing proc_fs_info rcu-delayedAl Viro1-1/+1
makes proc_pid_ns() safe from rcu pathwalk (put_pid_ns() is still synchronous, but that's not a problem - it does rcu-delay everything that needs to be) Reviewed-by: Christian Brauner <brauner@kernel.org> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2024-02-25procfs: move dropping pde and pid from ->evict_inode() to ->free_inode()Al Viro2-13/+8
that keeps both around until struct inode is freed, making access to them safe from rcu-pathwalk Acked-by: Christian Brauner <brauner@kernel.org> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2024-02-07fs/proc: do_task_stat: use sig->stats_lock to gather the threads/children statsOleg Nesterov1-26/+32
lock_task_sighand() can trigger a hard lockup. If NR_CPUS threads call do_task_stat() at the same time and the process has NR_THREADS, it will spin with irqs disabled O(NR_CPUS * NR_THREADS) time. Change do_task_stat() to use sig->stats_lock to gather the statistics outside of ->siglock protected section, in the likely case this code will run lockless. Link: https://lkml.kernel.org/r/20240123153357.GA21857@redhat.com Signed-off-by: Oleg Nesterov <oleg@redhat.com> Signed-off-by: Dylan Hatch <dylanbhatch@google.com> Cc: Eric W. Biederman <ebiederm@xmission.com> Cc: <stable@vger.kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2024-02-07fs/proc: do_task_stat: move thread_group_cputime_adjusted() outside of ↵Oleg Nesterov1-4/+6
lock_task_sighand() Patch series "fs/proc: do_task_stat: use sig->stats_". do_task_stat() has the same problem as getrusage() had before "getrusage: use sig->stats_lock rather than lock_task_sighand()": a hard lockup. If NR_CPUS threads call lock_task_sighand() at the same time and the process has NR_THREADS, spin_lock_irq will spin with irqs disabled O(NR_CPUS * NR_THREADS) time. This patch (of 3): thread_group_cputime() does its own locking, we can safely shift thread_group_cputime_adjusted() which does another for_each_thread loop outside of ->siglock protected section. Not only this removes for_each_thread() from the critical section with irqs disabled, this removes another case when stats_lock is taken with siglock held. We want to remove this dependency, then we can change the users of stats_lock to not disable irqs. Link: https://lkml.kernel.org/r/20240123153313.GA21832@redhat.com Link: https://lkml.kernel.org/r/20240123153355.GA21854@redhat.com Signed-off-by: Oleg Nesterov <oleg@redhat.com> Signed-off-by: Dylan Hatch <dylanbhatch@google.com> Cc: Eric W. Biederman <ebiederm@xmission.com> Cc: <stable@vger.kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2024-01-17Merge branch 'master' into mm-hotfixes-stableAndrew Morton1-15/+9
2024-01-17Merge tag 'mm-hotfixes-stable-2024-01-12-16-52' of ↵Linus Torvalds1-11/+13
git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm Pull misc hotfixes from Andrew Morton: "For once not mostly MM-related. 17 hotfixes. 10 address post-6.7 issues and the other 7 are cc:stable" * tag 'mm-hotfixes-stable-2024-01-12-16-52' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm: userfaultfd: avoid huge_zero_page in UFFDIO_MOVE MAINTAINERS: add entry for shrinker selftests: mm: hugepage-vmemmap fails on 64K page size systems mm/memory_hotplug: fix memmap_on_memory sysfs value retrieval mailmap: switch email for Tanzir Hasan mailmap: add old address mappings for Randy kernel/crash_core.c: make __crash_hotplug_lock static efi: disable mirror feature during crashkernel kexec: do syscore_shutdown() in kernel_kexec mailmap: update entry for Manivannan Sadhasivam fs/proc/task_mmu: move mmu notification mechanism inside mm lock mm: zswap: switch maintainers to recently active developers and reviewers scripts/decode_stacktrace.sh: optionally use LLVM utilities kasan: avoid resetting aux_lock lib/Kconfig.debug: disable CONFIG_DEBUG_INFO_BTF for Hexagon MAINTAINERS: update LTP maintainers kdump: defer the insertion of crashkernel resources
2024-01-12fs/proc/task_mmu: move mmu notification mechanism inside mm lockMuhammad Usama Anjum1-11/+13
Move mmu notification mechanism inside mm lock to prevent race condition in other components which depend on it. The notifier will invalidate memory range. Depending upon the number of iterations, different memory ranges would be invalidated. The following warning would be removed by this patch: WARNING: CPU: 0 PID: 5067 at arch/x86/kvm/../../../virt/kvm/kvm_main.c:734 kvm_mmu_notifier_change_pte+0x860/0x960 arch/x86/kvm/../../../virt/kvm/kvm_main.c:734 There is no behavioural and performance change with this patch when there is no component registered with the mmu notifier. [akpm@linux-foundation.org: narrow the scope of `range', per Sean] Link: https://lkml.kernel.org/r/20240109112445.590736-1-usama.anjum@collabora.com Fixes: 52526ca7fdb9 ("fs/proc/task_mmu: implement IOCTL to get and optionally clear info about PTEs") Signed-off-by: Muhammad Usama Anjum <usama.anjum@collabora.com> Reported-by: syzbot+81227d2bd69e9dedb802@syzkaller.appspotmail.com Link: https://lore.kernel.org/all/000000000000f6d051060c6785bc@google.com/ Reviewed-by: Sean Christopherson <seanjc@google.com> Cc: Andrei Vagin <avagin@google.com> Cc: Arnd Bergmann <arnd@arndb.de> Cc: David Hildenbrand <david@redhat.com> Cc: Hugh Dickins <hughd@google.com> Cc: Kefeng Wang <wangkefeng.wang@huawei.com> Cc: Liam R. Howlett <Liam.Howlett@oracle.com> Cc: Michał Mirosław <mirq-linux@rere.qmqm.pl> Cc: Peter Xu <peterx@redhat.com> Cc: Ryan Roberts <ryan.roberts@arm.com> Cc: Stephen Rothwell <sfr@canb.auug.org.au> Cc: Suren Baghdasaryan <surenb@google.com> Cc: <stable@vger.kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2024-01-11Merge tag 'pull-misc' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfsLinus Torvalds1-12/+2
Pull misc filesystem updates from Al Viro: "Misc cleanups (the part that hadn't been picked by individual fs trees)" * tag 'pull-misc' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs: apparmorfs: don't duplicate kfree_link() orangefs: saner arguments passing in readdir guts ocfs2_find_match(): there's no such thing as NULL or negative ->d_parent reiserfs_add_entry(): get rid of pointless namelen checks __ocfs2_add_entry(), ocfs2_prepare_dir_for_insert(): namelen checks ext4_add_entry(): ->d_name.len is never 0 befs: d_obtain_alias(ERR_PTR(...)) will do the right thing affs: d_obtain_alias(ERR_PTR(...)) will do the right thing /proc/sys: use d_splice_alias() calling conventions to simplify failure exits hostfs: use d_splice_alias() calling conventions to simplify failure exits udf_fiiter_add_entry(): check for zero ->d_name.len is bogus... udf: d_obtain_alias(ERR_PTR(...)) will do the right thing... udf: d_splice_alias() will do the right thing on ERR_PTR() inode nfsd: kill stale comment about simple_fill_super() requirements bfs_add_entry(): get rid of pointless ->d_name.len checks nilfs2: d_obtain_alias(ERR_PTR(...)) will do the right thing... zonefs: d_splice_alias() will do the right thing on ERR_PTR() inode
2024-01-10Merge tag 'sysctl-6.8-rc1' of ↵Linus Torvalds1-3/+7
git://git.kernel.org/pub/scm/linux/kernel/git/mcgrof/linux Pull sysctl updates from Luis Chamberlain: "To help make the move of sysctls out of kernel/sysctl.c not incur a size penalty sysctl has been changed to allow us to not require the sentinel, the final empty element on the sysctl array. Joel Granados has been doing all this work. In the v6.6 kernel we got the major infrastructure changes required to support this. For v6.7 we had all arch/ and drivers/ modified to remove the sentinel. For v6.8-rc1 we get a few more updates for fs/ directory only. The kernel/ directory is left but we'll save that for v6.9-rc1 as those patches are still being reviewed. After that we then can expect also the removal of the no longer needed check for procname == NULL. Let us recap the purpose of this work: - this helps reduce the overall build time size of the kernel and run time memory consumed by the kernel by about ~64 bytes per array - the extra 64-byte penalty is no longer inncurred now when we move sysctls out from kernel/sysctl.c to their own files Thomas Weißschuh also sent a few cleanups, for v6.9-rc1 we expect to see further work by Thomas Weißschuh with the constificatin of the struct ctl_table. Due to Joel Granados's work, and to help bring in new blood, I have suggested for him to become a maintainer and he's accepted. So for v6.9-rc1 I look forward to seeing him sent you a pull request for further sysctl changes. This also removes Iurii Zaikin as a maintainer as he has moved on to other projects and has had no time to help at all" * tag 'sysctl-6.8-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/mcgrof/linux: sysctl: remove struct ctl_path sysctl: delete unused define SYSCTL_PERM_EMPTY_DIR coda: Remove the now superfluous sentinel elements from ctl_table array sysctl: Remove the now superfluous sentinel elements from ctl_table array fs: Remove the now superfluous sentinel elements from ctl_table array cachefiles: Remove the now superfluous sentinel element from ctl_table array sysclt: Clarify the results of selftest run sysctl: Add a selftest for handling empty dirs sysctl: Fix out of bounds access for empty sysctl registers MAINTAINERS: Add Joel Granados as co-maintainer for proc sysctl MAINTAINERS: remove Iurii Zaikin from proc sysctl
2024-01-09Merge tag 'lsm-pr-20240105' of ↵Linus Torvalds2-15/+16
git://git.kernel.org/pub/scm/linux/kernel/git/pcmoore/lsm Pull security module updates from Paul Moore: - Add three new syscalls: lsm_list_modules(), lsm_get_self_attr(), and lsm_set_self_attr(). The first syscall simply lists the LSMs enabled, while the second and third get and set the current process' LSM attributes. Yes, these syscalls may provide similar functionality to what can be found under /proc or /sys, but they were designed to support multiple, simultaneaous (stacked) LSMs from the start as opposed to the current /proc based solutions which were created at a time when only one LSM was allowed to be active at a given time. We have spent considerable time discussing ways to extend the existing /proc interfaces to support multiple, simultaneaous LSMs and even our best ideas have been far too ugly to support as a kernel API; after +20 years in the kernel, I felt the LSM layer had established itself enough to justify a handful of syscalls. Support amongst the individual LSM developers has been nearly unanimous, with a single objection coming from Tetsuo (TOMOYO) as he is worried that the LSM_ID_XXX token concept will make it more difficult for out-of-tree LSMs to survive. Several members of the LSM community have demonstrated the ability for out-of-tree LSMs to continue to exist by picking high/unused LSM_ID values as well as pointing out that many kernel APIs rely on integer identifiers, e.g. syscalls (!), but unfortunately Tetsuo's objections remain. My personal opinion is that while I have no interest in penalizing out-of-tree LSMs, I'm not going to penalize in-tree development to support out-of-tree development, and I view this as a necessary step forward to support the push for expanded LSM stacking and reduce our reliance on /proc and /sys which has occassionally been problematic for some container users. Finally, we have included the linux-api folks on (all?) recent revisions of the patchset and addressed all of their concerns. - Add a new security_file_ioctl_compat() LSM hook to handle the 32-bit ioctls on 64-bit systems problem. This patch includes support for all of the existing LSMs which provide ioctl hooks, although it turns out only SELinux actually cares about the individual ioctls. It is worth noting that while Casey (Smack) and Tetsuo (TOMOYO) did not give explicit ACKs to this patch, they did both indicate they are okay with the changes. - Fix a potential memory leak in the CALIPSO code when IPv6 is disabled at boot. While it's good that we are fixing this, I doubt this is something users are seeing in the wild as you need to both disable IPv6 and then attempt to configure IPv6 labeled networking via NetLabel/CALIPSO; that just doesn't make much sense. Normally this would go through netdev, but Jakub asked me to take this patch and of all the trees I maintain, the LSM tree seemed like the best fit. - Update the LSM MAINTAINERS entry with additional information about our process docs, patchwork, bug reporting, etc. I also noticed that the Lockdown LSM is missing a dedicated MAINTAINERS entry so I've added that to the pull request. I've been working with one of the major Lockdown authors/contributors to see if they are willing to step up and assume a Lockdown maintainer role; hopefully that will happen soon, but in the meantime I'll continue to look after it. - Add a handful of mailmap entries for Serge Hallyn and myself. * tag 'lsm-pr-20240105' of git://git.kernel.org/pub/scm/linux/kernel/git/pcmoore/lsm: (27 commits) lsm: new security_file_ioctl_compat() hook lsm: Add a __counted_by() annotation to lsm_ctx.ctx calipso: fix memory leak in netlbl_calipso_add_pass() selftests: remove the LSM_ID_IMA check in lsm/lsm_list_modules_test MAINTAINERS: add an entry for the lockdown LSM MAINTAINERS: update the LSM entry mailmap: add entries for Serge Hallyn's dead accounts mailmap: update/replace my old email addresses lsm: mark the lsm_id variables are marked as static lsm: convert security_setselfattr() to use memdup_user() lsm: align based on pointer length in lsm_fill_user_ctx() lsm: consolidate buffer size handling into lsm_fill_user_ctx() lsm: correct error codes in security_getselfattr() lsm: cleanup the size counters in security_getselfattr() lsm: don't yet account for IMA in LSM_CONFIG_COUNT calculation lsm: drop LSM_ID_IMA LSM: selftests for Linux Security Module syscalls SELinux: Add selfattr hooks AppArmor: Add selfattr hooks Smack: implement setselfattr and getselfattr hooks ...
2024-01-09Merge tag 'mm-stable-2024-01-08-15-31' of ↵Linus Torvalds1-2/+18
git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm Pull MM updates from Andrew Morton: "Many singleton patches against the MM code. The patch series which are included in this merge do the following: - Peng Zhang has done some mapletree maintainance work in the series 'maple_tree: add mt_free_one() and mt_attr() helpers' 'Some cleanups of maple tree' - In the series 'mm: use memmap_on_memory semantics for dax/kmem' Vishal Verma has altered the interworking between memory-hotplug and dax/kmem so that newly added 'device memory' can more easily have its memmap placed within that newly added memory. - Matthew Wilcox continues folio-related work (including a few fixes) in the patch series 'Add folio_zero_tail() and folio_fill_tail()' 'Make folio_start_writeback return void' 'Fix fault handler's handling of poisoned tail pages' 'Convert aops->error_remove_page to ->error_remove_folio' 'Finish two folio conversions' 'More swap folio conversions' - Kefeng Wang has also contributed folio-related work in the series 'mm: cleanup and use more folio in page fault' - Jim Cromie has improved the kmemleak reporting output in the series 'tweak kmemleak report format'. - In the series 'stackdepot: allow evicting stack traces' Andrey Konovalov to permits clients (in this case KASAN) to cause eviction of no longer needed stack traces. - Charan Teja Kalla has fixed some accounting issues in the page allocator's atomic reserve calculations in the series 'mm: page_alloc: fixes for high atomic reserve caluculations'. - Dmitry Rokosov has added to the samples/ dorectory some sample code for a userspace memcg event listener application. See the series 'samples: introduce cgroup events listeners'. - Some mapletree maintanance work from Liam Howlett in the series 'maple_tree: iterator state changes'. - Nhat Pham has improved zswap's approach to writeback in the series 'workload-specific and memory pressure-driven zswap writeback'. - DAMON/DAMOS feature and maintenance work from SeongJae Park in the series 'mm/damon: let users feed and tame/auto-tune DAMOS' 'selftests/damon: add Python-written DAMON functionality tests' 'mm/damon: misc updates for 6.8' - Yosry Ahmed has improved memcg's stats flushing in the series 'mm: memcg: subtree stats flushing and thresholds'. - In the series 'Multi-size THP for anonymous memory' Ryan Roberts has added a runtime opt-in feature to transparent hugepages which improves performance by allocating larger chunks of memory during anonymous page faults. - Matthew Wilcox has also contributed some cleanup and maintenance work against eh buffer_head code int he series 'More buffer_head cleanups'. - Suren Baghdasaryan has done work on Andrea Arcangeli's series 'userfaultfd move option'. UFFDIO_MOVE permits userspace heap compaction algorithms to move userspace's pages around rather than UFFDIO_COPY'a alloc/copy/free. - Stefan Roesch has developed a 'KSM Advisor', in the series 'mm/ksm: Add ksm advisor'. This is a governor which tunes KSM's scanning aggressiveness in response to userspace's current needs. - Chengming Zhou has optimized zswap's temporary working memory use in the series 'mm/zswap: dstmem reuse optimizations and cleanups'. - Matthew Wilcox has performed some maintenance work on the writeback code, both code and within filesystems. The series is 'Clean up the writeback paths'. - Andrey Konovalov has optimized KASAN's handling of alloc and free stack traces for secondary-level allocators, in the series 'kasan: save mempool stack traces'. - Andrey also performed some KASAN maintenance work in the series 'kasan: assorted clean-ups'. - David Hildenbrand has gone to town on the rmap code. Cleanups, more pte batching, folio conversions and more. See the series 'mm/rmap: interface overhaul'. - Kinsey Ho has contributed some maintenance work on the MGLRU code in the series 'mm/mglru: Kconfig cleanup'. - Matthew Wilcox has contributed lruvec page accounting code cleanups in the series 'Remove some lruvec page accounting functions'" * tag 'mm-stable-2024-01-08-15-31' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm: (361 commits) mm, treewide: rename MAX_ORDER to MAX_PAGE_ORDER mm, treewide: introduce NR_PAGE_ORDERS selftests/mm: add separate UFFDIO_MOVE test for PMD splitting selftests/mm: skip test if application doesn't has root privileges selftests/mm: conform test to TAP format output selftests: mm: hugepage-mmap: conform to TAP format output selftests/mm: gup_test: conform test to TAP format output mm/selftests: hugepage-mremap: conform test to TAP format output mm/vmstat: move pgdemote_* out of CONFIG_NUMA_BALANCING mm: zsmalloc: return -ENOSPC rather than -EINVAL in zs_malloc while size is too large mm/memcontrol: remove __mod_lruvec_page_state() mm/khugepaged: use a folio more in collapse_file() slub: use a folio in __kmalloc_large_node slub: use folio APIs in free_large_kmalloc() slub: use alloc_pages_node() in alloc_slab_page() mm: remove inc/dec lruvec page state functions mm: ratelimit stat flush from workingset shrinker kasan: stop leaking stack trace handles mm/mglru: remove CONFIG_TRANSPARENT_HUGEPAGE mm/mglru: add dummy pmd_dirty() ...
2024-01-08Merge tag 'vfs-6.8.misc' of ↵Linus Torvalds1-1/+2
git://git.kernel.org/pub/scm/linux/kernel/git/vfs/vfs Pull misc vfs updates from Christian Brauner: "This contains the usual miscellaneous features, cleanups, and fixes for vfs and individual fses. Features: - Add Jan Kara as VFS reviewer - Show correct device and inode numbers in proc/<pid>/maps for vma files on stacked filesystems. This is now easily doable thanks to the backing file work from the last cycles. This comes with selftests Cleanups: - Remove a redundant might_sleep() from wait_on_inode() - Initialize pointer with NULL, not 0 - Clarify comment on access_override_creds() - Rework and simplify eventfd_signal() and eventfd_signal_mask() helpers - Process aio completions in batches to avoid needless wakeups - Completely decouple struct mnt_idmap from namespaces. We now only keep the actual idmapping around and don't stash references to namespaces - Reformat maintainer entries to indicate that a given subsystem belongs to fs/ - Simplify fput() for files that were never opened - Get rid of various pointless file helpers - Rename various file helpers - Rename struct file members after SLAB_TYPESAFE_BY_RCU switch from last cycle - Make relatime_need_update() return bool - Use GFP_KERNEL instead of GFP_USER when allocating superblocks - Replace deprecated ida_simple_*() calls with their current ida_*() counterparts Fixes: - Fix comments on user namespace id mapping helpers. They aren't kernel doc comments so they shouldn't be using /** - s/Retuns/Returns/g in various places - Add missing parameter documentation on can_move_mount_beneath() - Rename i_mapping->private_data to i_mapping->i_private_data - Fix a false-positive lockdep warning in pipe_write() for watch queues - Improve __fget_files_rcu() code generation to improve performance - Only notify writer that pipe resizing has finished after setting pipe->max_usage otherwise writers are never notified that the pipe has been resized and hang - Fix some kernel docs in hfsplus - s/passs/pass/g in various places - Fix kernel docs in ntfs - Fix kcalloc() arguments order reported by gcc 14 - Fix uninitialized value in reiserfs" * tag 'vfs-6.8.misc' of git://git.kernel.org/pub/scm/linux/kernel/git/vfs/vfs: (36 commits) reiserfs: fix uninit-value in comp_keys watch_queue: fix kcalloc() arguments order ntfs: dir.c: fix kernel-doc function parameter warnings fs: fix doc comment typo fs tree wide selftests/overlayfs: verify device and inode numbers in /proc/pid/maps fs/proc: show correct device and inode numbers in /proc/pid/maps eventfd: Remove usage of the deprecated ida_simple_xx() API fs: super: use GFP_KERNEL instead of GFP_USER for super block allocation fs/hfsplus: wrapper.c: fix kernel-doc warnings fs: add Jan Kara as reviewer fs/inode: Make relatime_need_update return bool pipe: wakeup wr_wait after setting max_usage file: remove __receive_fd() file: stop exposing receive_fd_user() fs: replace f_rcuhead with f_task_work file: remove pointless wrapper file: s/close_fd_get_file()/file_close_fd()/g Improve __fget_files_rcu() code generation (and thus __fget_light()) file: massage cleanup of files that failed to open fs/pipe: Fix lockdep false-positive in watchqueue pipe_write() ...
2023-12-28fs: Remove the now superfluous sentinel elements from ctl_table arrayJoel Granados1-1/+0
This commit comes at the tail end of a greater effort to remove the empty elements at the end of the ctl_table arrays (sentinels) which will reduce the overall build time size of the kernel and run time memory bloat by ~64 bytes per sentinel (further information Link : https://lore.kernel.org/all/ZO5Yx5JFogGi%2FcBo@bombadil.infradead.org/) Remove sentinel elements ctl_table struct. Special attention was placed in making sure that an empty directory for fs/verity was created when CONFIG_FS_VERITY_BUILTIN_SIGNATURES is not defined. In this case we use the register sysctl call that expects a size. Signed-off-by: Joel Granados <j.granados@samsung.com> Reviewed-by: Jan Kara <jack@suse.cz> Reviewed-by: "Darrick J. Wong" <djwong@kernel.org> Acked-by: Christian Brauner <brauner@kernel.org> Signed-off-by: Luis Chamberlain <mcgrof@kernel.org>
2023-12-28sysctl: Fix out of bounds access for empty sysctl registersJoel Granados1-2/+7
When registering tables to the sysctl subsystem there is a check to see if header is a permanently empty directory (used for mounts). This check evaluates the first element of the ctl_table. This results in an out of bounds evaluation when registering empty directories. The function register_sysctl_mount_point now passes a ctl_table of size 1 instead of size 0. It now relies solely on the type to identify a permanently empty register. Make sure that the ctl_table has at least one element before testing for permanent emptiness. Signed-off-by: Joel Granados <j.granados@samsung.com> Reported-by: kernel test robot <oliver.sang@intel.com> Closes: https://lore.kernel.org/oe-lkp/202311201431.57aae8f3-oliver.sang@intel.com Signed-off-by: Luis Chamberlain <mcgrof@kernel.org>
2023-12-21/proc/sys: use d_splice_alias() calling conventions to simplify failure exitsAl Viro1-12/+2
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2023-12-21fs/proc: show correct device and inode numbers in /proc/pid/mapsAndrei Vagin1-1/+2
/proc/pid/maps shows device and inode numbers of vma->vm_file-s. Here is an issue. If a mapped file is on a stackable file system (e.g., overlayfs), vma->vm_file is a backing file whose f_inode is on the underlying filesystem. To show correct numbers, we need to get a user file and shows its numbers. The same trick is used to show file paths in /proc/pid/maps. Cc: Alexander Mikhalitsyn <alexander@mihalicyn.com> Suggested-by: Amir Goldstein <amir73il@gmail.com> Signed-off-by: Andrei Vagin <avagin@google.com> Link: https://lore.kernel.org/r/20231214064439.1023011-1-avagin@google.com Reviewed-by: Amir Goldstein <amir73il@gmail.com> Signed-off-by: Christian Brauner <brauner@kernel.org>
2023-12-20mm: thp: introduce multi-size THP sysfs interfaceRyan Roberts1-1/+2
In preparation for adding support for anonymous multi-size THP, introduce new sysfs structure that will be used to control the new behaviours. A new directory is added under transparent_hugepage for each supported THP size, and contains an `enabled` file, which can be set to "inherit" (to inherit the global setting), "always", "madvise" or "never". For now, the kernel still only supports PMD-sized anonymous THP, so only 1 directory is populated. The first half of the change converts transhuge_vma_suitable() and hugepage_vma_check() so that they take a bitfield of orders for which the user wants to determine support, and the functions filter out all the orders that can't be supported, given the current sysfs configuration and the VMA dimensions. The resulting functions are renamed to thp_vma_suitable_orders() and thp_vma_allowable_orders() respectively. Convenience functions that take a single, unencoded order and return a boolean are also defined as thp_vma_suitable_order() and thp_vma_allowable_order(). The second half of the change implements the new sysfs interface. It has been done so that each supported THP size has a `struct thpsize`, which describes the relevant metadata and is itself a kobject. This is pretty minimal for now, but should make it easy to add new per-thpsize files to the interface if needed in future (e.g. per-size defrag). Rather than keep the `enabled` state directly in the struct thpsize, I've elected to directly encode it into huge_anon_orders_[always|madvise|inherit] bitfields since this reduces the amount of work required in thp_vma_allowable_orders() which is called for every page fault. See Documentation/admin-guide/mm/transhuge.rst, as modified by this commit, for details of how the new sysfs interface works. [ryan.roberts@arm.com: fix build warning when CONFIG_SYSFS is disabled] Link: https://lkml.kernel.org/r/20231211125320.3997543-1-ryan.roberts@arm.com Link: https://lkml.kernel.org/r/20231207161211.2374093-4-ryan.roberts@arm.com Signed-off-by: Ryan Roberts <ryan.roberts@arm.com> Reviewed-by: Barry Song <v-songbaohua@oppo.com> Tested-by: Kefeng Wang <wangkefeng.wang@huawei.com> Tested-by: John Hubbard <jhubbard@nvidia.com> Acked-by: David Hildenbrand <david@redhat.com> Cc: Alistair Popple <apopple@nvidia.com> Cc: Anshuman Khandual <anshuman.khandual@arm.com> Cc: Catalin Marinas <catalin.marinas@arm.com> Cc: David Rientjes <rientjes@google.com> Cc: "Huang, Ying" <ying.huang@intel.com> Cc: Hugh Dickins <hughd@google.com> Cc: Itaru Kitayama <itaru.kitayama@gmail.com> Cc: Kirill A. Shutemov <kirill.shutemov@linux.intel.com> Cc: Luis Chamberlain <mcgrof@kernel.org> Cc: Matthew Wilcox (Oracle) <willy@infradead.org> Cc: Vlastimil Babka <vbabka@suse.cz> Cc: Yang Shi <shy828301@gmail.com> Cc: Yin Fengwei <fengwei.yin@intel.com> Cc: Yu Zhao <yuzhao@google.com> Cc: Zi Yan <ziy@nvidia.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2023-12-10fs/proc/task_mmu: report SOFT_DIRTY bits through the PAGEMAP_SCAN ioctlAndrei Vagin1-1/+16
The PAGEMAP_SCAN ioctl returns information regarding page table entries. It is more efficient compared to reading pagemap files. CRIU can start to utilize this ioctl, but it needs info about soft-dirty bits to track memory changes. We are aware of a new method for tracking memory changes implemented in the PAGEMAP_SCAN ioctl. For CRIU, the primary advantage of this method is its usability by unprivileged users. However, it is not feasible to transparently replace the soft-dirty tracker with the new one. The main problem here is userfault descriptors that have to be preserved between pre-dump iterations. It means criu continues supporting the soft-dirty method to avoid breakage for current users. The new method will be implemented as a separate feature. [avagin@google.com: update tools/include/uapi/linux/fs.h] Link: https://lkml.kernel.org/r/20231107164139.576046-1-avagin@google.com Link: https://lkml.kernel.org/r/20231106220959.296568-1-avagin@google.com Signed-off-by: Andrei Vagin <avagin@google.com> Reviewed-by: Muhammad Usama Anjum <usama.anjum@collabora.com> Cc: Michał Mirosław <mirq-linux@rere.qmqm.pl> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2023-12-06mm/pagemap: fix wr-protect even if PM_SCAN_WP_MATCHING not setPeter Xu1-1/+1
The new pagemap ioctl contains a fast path for wr-protections without looking into category masks. It forgets to check PM_SCAN_WP_MATCHING before applying the wr-protections. It can cause, e.g., pte markers installed on archs that do not even support uffd wr-protect. WARNING: CPU: 0 PID: 5059 at mm/memory.c:1520 zap_pte_range mm/memory.c:1520 [inline] Link: https://lkml.kernel.org/r/20231116201547.536857-3-peterx@redhat.com Fixes: 12f6b01a0bcb ("fs/proc/task_mmu: add fast paths to get/clear PAGE_IS_WRITTEN flag") Signed-off-by: Peter Xu <peterx@redhat.com> Reported-by: syzbot+7ca4b2719dc742b8d0a4@syzkaller.appspotmail.com Reviewed-by: David Hildenbrand <david@redhat.com> Reviewed-by: Andrei Vagin <avagin@gmail.com> Cc: Muhammad Usama Anjum <usama.anjum@collabora.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2023-12-06mm/pagemap: fix ioctl(PAGEMAP_SCAN) on vma checkPeter Xu1-4/+20
Patch series "mm/pagemap: A few fixes to the recent PAGEMAP_SCAN". This series should fix two known reports from syzbot on the new PAGEMAP_SCAN ioctl(): https://lore.kernel.org/all/000000000000b0e576060a30ee3b@google.com/ https://lore.kernel.org/all/000000000000773fa7060a31e2cc@google.com/ The 3rd patch is something I found when testing these patches. This patch (of 3): The new ioctl(PAGEMAP_SCAN) relies on vma wr-protect capability provided by userfault, however in the vma test it didn't explicitly require the vma to have wr-protect function enabled, even if PM_SCAN_WP_MATCHING flag is set. It means the pagemap code can now apply uffd-wp bit to a page in the vma even if not registered to userfaultfd at all. Then in whatever way as long as the pte got written and page fault resolved, we'll apply the write bit even if uffd-wp bit is set. We'll see a pte that has both UFFD_WP and WRITE bit set. Anything later that looks up the pte for uffd-wp bit will trigger the warning: WARNING: CPU: 1 PID: 5071 at arch/x86/include/asm/pgtable.h:403 pte_uffd_wp arch/x86/include/asm/pgtable.h:403 [inline] Fix it by doing proper check over the vma attributes when PM_SCAN_WP_MATCHING is specified. Link: https://lkml.kernel.org/r/20231116201547.536857-1-peterx@redhat.com Link: https://lkml.kernel.org/r/20231116201547.536857-2-peterx@redhat.com Fixes: 52526ca7fdb9 ("fs/proc/task_mmu: implement IOCTL to get and optionally clear info about PTEs") Signed-off-by: Peter Xu <peterx@redhat.com> Reported-by: syzbot+e94c5aaf7890901ebf9b@syzkaller.appspotmail.com Reviewed-by: David Hildenbrand <david@redhat.com> Reviewed-by: Andrei Vagin <avagin@gmail.com> Reviewed-by: Muhammad Usama Anjum <usama.anjum@collabora.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2023-11-12proc: Use lsmids instead of lsm names for attrsCasey Schaufler2-15/+16
Use the LSM ID number instead of the LSM name to identify which security module's attibute data should be shown in /proc/self/attr. The security_[gs]etprocattr() functions have been changed to expect the LSM ID. The change from a string comparison to an integer comparison in these functions will provide a minor performance improvement. Cc: linux-fsdevel@vger.kernel.org Signed-off-by: Casey Schaufler <casey@schaufler-ca.com> Reviewed-by: Kees Cook <keescook@chromium.org> Reviewed-by: Serge Hallyn <serge@hallyn.com> Reviewed-by: Mickael Salaun <mic@digikod.net> Reviewed-by: John Johansen <john.johansen@canonical.com> Signed-off-by: Paul Moore <paul@paul-moore.com>
2023-11-02Merge tag 'mm-nonmm-stable-2023-11-02-14-08' of ↵Linus Torvalds4-41/+40
git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm Pull non-MM updates from Andrew Morton: "As usual, lots of singleton and doubleton patches all over the tree and there's little I can say which isn't in the individual changelogs. The lengthier patch series are - 'kdump: use generic functions to simplify crashkernel reservation in arch', from Baoquan He. This is mainly cleanups and consolidation of the 'crashkernel=' kernel parameter handling - After much discussion, David Laight's 'minmax: Relax type checks in min() and max()' is here. Hopefully reduces some typecasting and the use of min_t() and max_t() - A group of patches from Oleg Nesterov which clean up and slightly fix our handling of reads from /proc/PID/task/... and which remove task_struct.thread_group" * tag 'mm-nonmm-stable-2023-11-02-14-08' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm: (64 commits) scripts/gdb/vmalloc: disable on no-MMU scripts/gdb: fix usage of MOD_TEXT not defined when CONFIG_MODULES=n .mailmap: add address mapping for Tomeu Vizoso mailmap: update email address for Claudiu Beznea tools/testing/selftests/mm/run_vmtests.sh: lower the ptrace permissions .mailmap: map Benjamin Poirier's address scripts/gdb: add lx_current support for riscv ocfs2: fix a spelling typo in comment proc: test ProtectionKey in proc-empty-vm test proc: fix proc-empty-vm test with vsyscall fs/proc/base.c: remove unneeded semicolon do_io_accounting: use sig->stats_lock do_io_accounting: use __for_each_thread() ocfs2: replace BUG_ON() at ocfs2_num_free_extents() with ocfs2_error() ocfs2: fix a typo in a comment scripts/show_delta: add __main__ judgement before main code treewide: mark stuff as __ro_after_init fs: ocfs2: check status values proc: test /proc/${pid}/statm compiler.h: move __is_constexpr() to compiler.h ...
2023-11-02Merge tag 'mm-stable-2023-11-01-14-33' of ↵Linus Torvalds3-4/+734
git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm Pull MM updates from Andrew Morton: "Many singleton patches against the MM code. The patch series which are included in this merge do the following: - Kemeng Shi has contributed some compation maintenance work in the series 'Fixes and cleanups to compaction' - Joel Fernandes has a patchset ('Optimize mremap during mutual alignment within PMD') which fixes an obscure issue with mremap()'s pagetable handling during a subsequent exec(), based upon an implementation which Linus suggested - More DAMON/DAMOS maintenance and feature work from SeongJae Park i the following patch series: mm/damon: misc fixups for documents, comments and its tracepoint mm/damon: add a tracepoint for damos apply target regions mm/damon: provide pseudo-moving sum based access rate mm/damon: implement DAMOS apply intervals mm/damon/core-test: Fix memory leaks in core-test mm/damon/sysfs-schemes: Do DAMOS tried regions update for only one apply interval - In the series 'Do not try to access unaccepted memory' Adrian Hunter provides some fixups for the recently-added 'unaccepted memory' feature. To increase the feature's checking coverage. 'Plug a few gaps where RAM is exposed without checking if it is unaccepted memory' - In the series 'cleanups for lockless slab shrink' Qi Zheng has done some maintenance work which is preparation for the lockless slab shrinking code - Qi Zheng has redone the earlier (and reverted) attempt to make slab shrinking lockless in the series 'use refcount+RCU method to implement lockless slab shrink' - David Hildenbrand contributes some maintenance work for the rmap code in the series 'Anon rmap cleanups' - Kefeng Wang does more folio conversions and some maintenance work in the migration code. Series 'mm: migrate: more folio conversion and unification' - Matthew Wilcox has fixed an issue in the buffer_head code which was causing long stalls under some heavy memory/IO loads. Some cleanups were added on the way. Series 'Add and use bdev_getblk()' - In the series 'Use nth_page() in place of direct struct page manipulation' Zi Yan has fixed a potential issue with the direct manipulation of hugetlb page frames - In the series 'mm: hugetlb: Skip initialization of gigantic tail struct pages if freed by HVO' has improved our handling of gigantic pages in the hugetlb vmmemmep optimizaton code. This provides significant boot time improvements when significant amounts of gigantic pages are in use - Matthew Wilcox has sent the series 'Small hugetlb cleanups' - code rationalization and folio conversions in the hugetlb code - Yin Fengwei has improved mlock()'s handling of large folios in the series 'support large folio for mlock' - In the series 'Expose swapcache stat for memcg v1' Liu Shixin has added statistics for memcg v1 users which are available (and useful) under memcg v2 - Florent Revest has enhanced the MDWE (Memory-Deny-Write-Executable) prctl so that userspace may direct the kernel to not automatically propagate the denial to child processes. The series is named 'MDWE without inheritance' - Kefeng Wang has provided the series 'mm: convert numa balancing functions to use a folio' which does what it says - In the series 'mm/ksm: add fork-exec support for prctl' Stefan Roesch makes is possible for a process to propagate KSM treatment across exec() - Huang Ying has enhanced memory tiering's calculation of memory distances. This is used to permit the dax/kmem driver to use 'high bandwidth memory' in addition to Optane Data Center Persistent Memory Modules (DCPMM). The series is named 'memory tiering: calculate abstract distance based on ACPI HMAT' - In the series 'Smart scanning mode for KSM' Stefan Roesch has optimized KSM by teaching it to retain and use some historical information from previous scans - Yosry Ahmed has fixed some inconsistencies in memcg statistics in the series 'mm: memcg: fix tracking of pending stats updates values' - In the series 'Implement IOCTL to get and optionally clear info about PTEs' Peter Xu has added an ioctl to /proc/<pid>/pagemap which permits us to atomically read-then-clear page softdirty state. This is mainly used by CRIU - Hugh Dickins contributed the series 'shmem,tmpfs: general maintenance', a bunch of relatively minor maintenance tweaks to this code - Matthew Wilcox has increased the use of the VMA lock over file-backed page faults in the series 'Handle more faults under the VMA lock'. Some rationalizations of the fault path became possible as a result - In the series 'mm/rmap: convert page_move_anon_rmap() to folio_move_anon_rmap()' David Hildenbrand has implemented some cleanups and folio conversions - In the series 'various improvements to the GUP interface' Lorenzo Stoakes has simplified and improved the GUP interface with an eye to providing groundwork for future improvements - Andrey Konovalov has sent along the series 'kasan: assorted fixes and improvements' which does those things - Some page allocator maintenance work from Kemeng Shi in the series 'Two minor cleanups to break_down_buddy_pages' - In thes series 'New selftest for mm' Breno Leitao has developed another MM self test which tickles a race we had between madvise() and page faults - In the series 'Add folio_end_read' Matthew Wilcox provides cleanups and an optimization to the core pagecache code - Nhat Pham has added memcg accounting for hugetlb memory in the series 'hugetlb memcg accounting' - Cleanups and rationalizations to the pagemap code from Lorenzo Stoakes, in the series 'Abstract vma_merge() and split_vma()' - Audra Mitchell has fixed issues in the procfs page_owner code's new timestamping feature which was causing some misbehaviours. In the series 'Fix page_owner's use of free timestamps' - Lorenzo Stoakes has fixed the handling of new mappings of sealed files in the series 'permit write-sealed memfd read-only shared mappings' - Mike Kravetz has optimized the hugetlb vmemmap optimization in the series 'Batch hugetlb vmemmap modification operations' - Some buffer_head folio conversions and cleanups from Matthew Wilcox in the series 'Finish the create_empty_buffers() transition' - As a page allocator performance optimization Huang Ying has added automatic tuning to the allocator's per-cpu-pages feature, in the series 'mm: PCP high auto-tuning' - Roman Gushchin has contributed the patchset 'mm: improve performance of accounted kernel memory allocations' which improves their performance by ~30% as measured by a micro-benchmark - folio conversions from Kefeng Wang in the series 'mm: convert page cpupid functions to folios' - Some kmemleak fixups in Liu Shixin's series 'Some bugfix about kmemleak' - Qi Zheng has improved our handling of memoryless nodes by keeping them off the allocation fallback list. This is done in the series 'handle memoryless nodes more appropriately' - khugepaged conversions from Vishal Moola in the series 'Some khugepaged folio conversions'" [ bcachefs conflicts with the dynamically allocated shrinkers have been resolved as per Stephen Rothwell in https://lore.kernel.org/all/20230913093553.4290421e@canb.auug.org.au/ with help from Qi Zheng. The clone3 test filtering conflict was half-arsed by yours truly ] * tag 'mm-stable-2023-11-01-14-33' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm: (406 commits) mm/damon/sysfs: update monitoring target regions for online input commit mm/damon/sysfs: remove requested targets when online-commit inputs selftests: add a sanity check for zswap Documentation: maple_tree: fix word spelling error mm/vmalloc: fix the unchecked dereference warning in vread_iter() zswap: export compression failure stats Documentation: ubsan: drop "the" from article title mempolicy: migration attempt to match interleave nodes mempolicy: mmap_lock is not needed while migrating folios mempolicy: alloc_pages_mpol() for NUMA policy without vma mm: add page_rmappable_folio() wrapper mempolicy: remove confusing MPOL_MF_LAZY dead code mempolicy: mpol_shared_policy_init() without pseudo-vma mempolicy trivia: use pgoff_t in shared mempolicy tree mempolicy trivia: slightly more consistent naming mempolicy trivia: delete those ancient pr_debug()s mempolicy: fix migrate_pages(2) syscall return nr_failed kernfs: drop shared NUMA mempolicy hooks hugetlbfs: drop shared NUMA mempolicy pretence mm/damon/sysfs-test: add a unit test for damon_sysfs_set_targets() ...
2023-11-01Merge tag 'sysctl-6.7-rc1' of ↵Linus Torvalds1-1/+7
git://git.kernel.org/pub/scm/linux/kernel/git/mcgrof/linux Pull sysctl updates from Luis Chamberlain: "To help make the move of sysctls out of kernel/sysctl.c not incur a size penalty sysctl has been changed to allow us to not require the sentinel, the final empty element on the sysctl array. Joel Granados has been doing all this work. On the v6.6 kernel we got the major infrastructure changes required to support this. For v6.7-rc1 we have all arch/ and drivers/ modified to remove the sentinel. Both arch and driver changes have been on linux-next for a bit less than a month. It is worth re-iterating the value: - this helps reduce the overall build time size of the kernel and run time memory consumed by the kernel by about ~64 bytes per array - the extra 64-byte penalty is no longer inncurred now when we move sysctls out from kernel/sysctl.c to their own files For v6.8-rc1 expect removal of all the sentinels and also then the unneeded check for procname == NULL. The last two patches are fixes recently merged by Krister Johansen which allow us again to use softlockup_panic early on boot. This used to work but the alias work broke it. This is useful for folks who want to detect softlockups super early rather than wait and spend money on cloud solutions with nothing but an eventual hung kernel. Although this hadn't gone through linux-next it's also a stable fix, so we might as well roll through the fixes now" * tag 'sysctl-6.7-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/mcgrof/linux: (23 commits) watchdog: move softlockup_panic back to early_param proc: sysctl: prevent aliased sysctls from getting passed to init intel drm: Remove now superfluous sentinel element from ctl_table array Drivers: hv: Remove now superfluous sentinel element from ctl_table array raid: Remove now superfluous sentinel element from ctl_table array fw loader: Remove the now superfluous sentinel element from ctl_table array sgi-xp: Remove the now superfluous sentinel element from ctl_table array vrf: Remove the now superfluous sentinel element from ctl_table array char-misc: Remove the now superfluous sentinel element from ctl_table array infiniband: Remove the now superfluous sentinel element from ctl_table array macintosh: Remove the now superfluous sentinel element from ctl_table array parport: Remove the now superfluous sentinel element from ctl_table array scsi: Remove now superfluous sentinel element from ctl_table array tty: Remove now superfluous sentinel element from ctl_table array xen: Remove now superfluous sentinel element from ctl_table array hpet: Remove now superfluous sentinel element from ctl_table array c-sky: Remove now superfluous sentinel element from ctl_talbe array powerpc: Remove now superfluous sentinel element from ctl_table arrays riscv: Remove now superfluous sentinel element from ctl_table array x86/vdso: Remove now superfluous sentinel element from ctl_table array ...
2023-11-01