1. 02 Aug, 2023 1 commit
  2. 26 Jul, 2023 1 commit
  3. 14 Jul, 2023 2 commits
    • Wang Ming's avatar
      fs: Fix error checking for d_hash_and_lookup() · 0d5a4f8f
      Wang Ming authored
      The d_hash_and_lookup() function returns error pointers or NULL.
      Most incorrect error checks were fixed, but the one in int path_pts()
      was forgotten.
      
      Fixes: eedf265a ("devpts: Make each mount of devpts an independent filesystem.")
      Signed-off-by: default avatarWang Ming <machel@vivo.com>
      Message-Id: <20230713120555.7025-1-machel@vivo.com>
      Signed-off-by: default avatarChristian Brauner <brauner@kernel.org>
      0d5a4f8f
    • Christian Brauner's avatar
      attr: block mode changes of symlinks · 5d1f903f
      Christian Brauner authored
      Changing the mode of symlinks is meaningless as the vfs doesn't take the
      mode of a symlink into account during path lookup permission checking.
      
      However, the vfs doesn't block mode changes on symlinks. This however,
      has lead to an untenable mess roughly classifiable into the following
      two categories:
      
      (1) Filesystems that don't implement a i_op->setattr() for symlinks.
      
          Such filesystems may or may not know that without i_op->setattr()
          defined, notify_change() falls back to simple_setattr() causing the
          inode's mode in the inode cache to be changed.
      
          That's a generic issue as this will affect all non-size changing
          inode attributes including ownership changes.
      
          Example: afs
      
      (2) Filesystems that fail with EOPNOTSUPP but change the mode of the
          symlink nonetheless.
      
          Some filesystems will happily update the mode of a symlink but still
          return EOPNOTSUPP. This is the biggest source of confusion for
          userspace.
      
          The EOPNOTSUPP in this case comes from POSIX ACLs. Specifically it
          comes from filesystems that call posix_acl_chmod(), e.g., btrfs via
      
              if (!err && attr->ia_valid & ATTR_MODE)
                      err = posix_acl_chmod(idmap, dentry, inode->i_mode);
      
          Filesystems including btrfs don't implement i_op->set_acl() so
          posix_acl_chmod() will report EOPNOTSUPP.
      
          When posix_acl_chmod() is called, most filesystems will have
          finished updating the inode.
      
          Perversely, this has the consequences that this behavior may depend
          on two kconfig options and mount options:
      
          * CONFIG_POSIX_ACL={y,n}
          * CONFIG_${FSTYPE}_POSIX_ACL={y,n}
          * Opt_acl, Opt_noacl
      
          Example: btrfs, ext4, xfs
      
      The only way to change the mode on a symlink currently involves abusing
      an O_PATH file descriptor in the following manner:
      
              fd = openat(-1, "/path/to/link", O_CLOEXEC | O_PATH | O_NOFOLLOW);
      
              char path[PATH_MAX];
              snprintf(path, sizeof(path), "/proc/self/fd/%d", fd);
              chmod(path, 0000);
      
      But for most major filesystems with POSIX ACL support such as btrfs,
      ext4, ceph, tmpfs, xfs and others this will fail with EOPNOTSUPP with
      the mode still updated due to the aforementioned posix_acl_chmod()
      nonsense.
      
      So, given that for all major filesystems this would fail with EOPNOTSUPP
      and that both glibc (cf. [1]) and musl (cf. [2]) outright block mode
      changes on symlinks we should just try and block mode changes on
      symlinks directly in the vfs and have a clean break with this nonsense.
      
      If this causes any regressions, we do the next best thing and fix up all
      filesystems that do return EOPNOTSUPP with the mode updated to not call
      posix_acl_chmod() on symlinks.
      
      But as usual, let's try the clean cut solution first. It's a simple
      patch that can be easily reverted. Not marking this for backport as I'll
      do that manually if we're reasonably sure that this works and there are
      no strong objections.
      
      We could block this in chmod_common() but it's more appropriate to do it
      notify_change() as it will also mean that we catch filesystems that
      change symlink permissions explicitly or accidently.
      
      Similar proposals were floated in the past as in [3] and [4] and again
      recently in [5]. There's also a couple of bugs about this inconsistency
      as in [6] and [7].
      
      Link: https://sourceware.org/git/?p=glibc.git;a=blob;f=sysdeps/unix/sysv/linux/fchmodat.c;h=99527a3727e44cb8661ee1f743068f108ec93979;hb=HEAD [1]
      Link: https://git.musl-libc.org/cgit/musl/tree/src/stat/fchmodat.c [2]
      Link: https://lore.kernel.org/all/20200911065733.GA31579@infradead.org [3]
      Link: https://sourceware.org/legacy-ml/libc-alpha/2020-02/msg00518.html [4]
      Link: https://lore.kernel.org/lkml/87lefmbppo.fsf@oldenburg.str.redhat.com [5]
      Link: https://sourceware.org/legacy-ml/libc-alpha/2020-02/msg00467.html [6]
      Link: https://sourceware.org/bugzilla/show_bug.cgi?id=14578#c17 [7]
      Reviewed-by: default avatarAleksa Sarai <cyphar@cyphar.com>
      Reviewed-by: default avatarChristoph Hellwig <hch@lst.de>
      Cc: stable@vger.kernel.org # please backport to all LTSes but not before v6.6-rc2 is tagged
      Suggested-by: default avatarChristoph Hellwig <hch@lst.de>
      Suggested-by: default avatarFlorian Weimer <fweimer@redhat.com>
      Message-Id: <20230712-vfs-chmod-symlinks-v2-1-08cfb92b61dd@kernel.org>
      Signed-off-by: default avatarChristian Brauner <brauner@kernel.org>
      5d1f903f
  4. 11 Jul, 2023 1 commit
    • Wen Yang's avatar
      eventfd: prevent underflow for eventfd semaphores · 758b4920
      Wen Yang authored
      For eventfd with flag EFD_SEMAPHORE, when its ctx->count is 0, calling
      eventfd_ctx_do_read will cause ctx->count to overflow to ULLONG_MAX.
      
      An underflow can happen with EFD_SEMAPHORE eventfds in at least the
      following three subsystems:
      
      (1) virt/kvm/eventfd.c
      (2) drivers/vfio/virqfd.c
      (3) drivers/virt/acrn/irqfd.c
      
      where (2) and (3) are just modeled after (1). An eventfd must be
      specified for use with the KVM_IRQFD ioctl(). This can also be an
      EFD_SEMAPHORE eventfd. When the eventfd count is zero or has been
      decremented to zero an underflow can be triggered when the irqfd is shut
      down by raising the KVM_IRQFD_FLAG_DEASSIGN flag in the KVM_IRQFD
      ioctl():
      
              // ctx->count == 0
              kvm_vm_ioctl()
              -> kvm_irqfd()
                 -> kvm_irqfd_deassign()
                    -> irqfd_deactivate()
                       -> irqfd_shutdown()
                          -> eventfd_ctx_remove_wait_queue(&cnt)
                             -> eventfd_ctx_do_read(&cnt)
      
      Userspace polling on the eventfd wouldn't notice the underflow because 1
      is always returned as the value from eventfd_read() while ctx->count
      would've underflowed. It's not a huge deal because this should only be
      happening when the irqfd is shutdown but we should still fix it and
      avoid the spurious wakeup.
      
      Fixes: cb289d62 ("eventfd - allow atomic read and waitqueue remove")
      Signed-off-by: default avatarWen Yang <wenyang.linux@foxmail.com>
      Cc: Alexander Viro <viro@zeniv.linux.org.uk>
      Cc: Jens Axboe <axboe@kernel.dk>
      Cc: Christian Brauner <brauner@kernel.org>
      Cc: Christoph Hellwig <hch@lst.de>
      Cc: Dylan Yudaken <dylany@fb.com>
      Cc: David Woodhouse <dwmw@amazon.co.uk>
      Cc: Matthew Wilcox <willy@infradead.org>
      Cc: linux-fsdevel@vger.kernel.org
      Cc: linux-kernel@vger.kernel.org
      Message-Id: <tencent_7588DFD1F365950A757310D764517A14B306@qq.com>
      [brauner: rewrite commit message and add explanation how this underflow can happen]
      Signed-off-by: default avatarChristian Brauner <brauner@kernel.org>
      758b4920
  5. 10 Jul, 2023 11 commits
  6. 09 Jul, 2023 10 commits
  7. 08 Jul, 2023 14 commits
    • Hugh Dickins's avatar
      mm: lock newly mapped VMA with corrected ordering · 1c7873e3
      Hugh Dickins authored
      Lockdep is certainly right to complain about
      
        (&vma->vm_lock->lock){++++}-{3:3}, at: vma_start_write+0x2d/0x3f
                       but task is already holding lock:
        (&mapping->i_mmap_rwsem){+.+.}-{3:3}, at: mmap_region+0x4dc/0x6db
      
      Invert those to the usual ordering.
      
      Fixes: 33313a74 ("mm: lock newly mapped VMA which can be modified after it becomes visible")
      Cc: stable@vger.kernel.org
      Signed-off-by: default avatarHugh Dickins <hughd@google.com>
      Tested-by: default avatarSuren Baghdasaryan <surenb@google.com>
      Signed-off-by: default avatarLinus Torvalds <torvalds@linux-foundation.org>
      1c7873e3
    • Linus Torvalds's avatar
      Merge tag 'mm-hotfixes-stable-2023-07-08-10-43' of... · 946c6b59
      Linus Torvalds authored
      Merge tag 'mm-hotfixes-stable-2023-07-08-10-43' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm
      
      Pull hotfixes from Andrew Morton:
       "16 hotfixes. Six are cc:stable and the remainder address post-6.4
        issues"
      
      The merge undoes the disabling of the CONFIG_PER_VMA_LOCK feature, since
      it was all hopefully fixed in mainline.
      
      * tag 'mm-hotfixes-stable-2023-07-08-10-43' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm:
        lib: dhry: fix sleeping allocations inside non-preemptable section
        kasan, slub: fix HW_TAGS zeroing with slub_debug
        kasan: fix type cast in memory_is_poisoned_n
        mailmap: add entries for Heiko Stuebner
        mailmap: update manpage link
        bootmem: remove the vmemmap pages from kmemleak in free_bootmem_page
        MAINTAINERS: add linux-next info
        mailmap: add Markus Schneider-Pargmann
        writeback: account the number of pages written back
        mm: call arch_swap_restore() from do_swap_page()
        squashfs: fix cache race with migration
        mm/hugetlb.c: fix a bug within a BUG(): inconsistent pte comparison
        docs: update ocfs2-devel mailing list address
        MAINTAINERS: update ocfs2-devel mailing list address
        mm: disable CONFIG_PER_VMA_LOCK until its fixed
        fork: lock VMAs of the parent process when forking
      946c6b59
    • Suren Baghdasaryan's avatar
      fork: lock VMAs of the parent process when forking · fb49c455
      Suren Baghdasaryan authored
      When forking a child process, the parent write-protects anonymous pages
      and COW-shares them with the child being forked using copy_present_pte().
      
      We must not take any concurrent page faults on the source vma's as they
      are being processed, as we expect both the vma and the pte's behind it
      to be stable.  For example, the anon_vma_fork() expects the parents
      vma->anon_vma to not change during the vma copy.
      
      A concurrent page fault on a page newly marked read-only by the page
      copy might trigger wp_page_copy() and a anon_vma_prepare(vma) on the
      source vma, defeating the anon_vma_clone() that wasn't done because the
      parent vma originally didn't have an anon_vma, but we now might end up
      copying a pte entry for a page that has one.
      
      Before the per-vma lock based changes, the mmap_lock guaranteed
      exclusion with concurrent page faults.  But now we need to do a
      vma_start_write() to make sure no concurrent faults happen on this vma
      while it is being processed.
      
      This fix can potentially regress some fork-heavy workloads.  Kernel
      build time did not show noticeable regression on a 56-core machine while
      a stress test mapping 10000 VMAs and forking 5000 times in a tight loop
      shows ~5% regression.  If such fork time regression is unacceptable,
      disabling CONFIG_PER_VMA_LOCK should restore its performance.  Further
      optimizations are possible if this regression proves to be problematic.
      Suggested-by: default avatarDavid Hildenbrand <david@redhat.com>
      Reported-by: default avatarJiri Slaby <jirislaby@kernel.org>
      Closes: https://lore.kernel.org/all/dbdef34c-3a07-5951-e1ae-e9c6e3cdf51b@kernel.org/Reported-by: default avatarHolger Hoffstätte <holger@applied-asynchrony.com>
      Closes: https://lore.kernel.org/all/b198d649-f4bf-b971-31d0-e8433ec2a34c@applied-asynchrony.com/Reported-by: default avatarJacob Young <jacobly.alt@gmail.com>
      Closes: https://bugzilla.kernel.org/show_bug.cgi?id=217624
      Fixes: 0bff0aae ("x86/mm: try VMA lock-based page fault handling first")
      Cc: stable@vger.kernel.org
      Signed-off-by: default avatarSuren Baghdasaryan <surenb@google.com>
      Signed-off-by: default avatarLinus Torvalds <torvalds@linux-foundation.org>
      fb49c455
    • Suren Baghdasaryan's avatar
      mm: lock newly mapped VMA which can be modified after it becomes visible · 33313a74
      Suren Baghdasaryan authored
      mmap_region adds a newly created VMA into VMA tree and might modify it
      afterwards before dropping the mmap_lock.  This poses a problem for page
      faults handled under per-VMA locks because they don't take the mmap_lock
      and can stumble on this VMA while it's still being modified.  Currently
      this does not pose a problem since post-addition modifications are done
      only for file-backed VMAs, which are not handled under per-VMA lock.
      However, once support for handling file-backed page faults with per-VMA
      locks is added, this will become a race.
      
      Fix this by write-locking the VMA before inserting it into the VMA tree.
      Other places where a new VMA is added into VMA tree do not modify it
      after the insertion, so do not need the same locking.
      
      Cc: stable@vger.kernel.org
      Signed-off-by: default avatarSuren Baghdasaryan <surenb@google.com>
      Signed-off-by: default avatarLinus Torvalds <torvalds@linux-foundation.org>
      33313a74
    • Suren Baghdasaryan's avatar
      mm: lock a vma before stack expansion · c137381f
      Suren Baghdasaryan authored
      With recent changes necessitating mmap_lock to be held for write while
      expanding a stack, per-VMA locks should follow the same rules and be
      write-locked to prevent page faults into the VMA being expanded. Add
      the necessary locking.
      
      Cc: stable@vger.kernel.org
      Signed-off-by: default avatarSuren Baghdasaryan <surenb@google.com>
      Signed-off-by: default avatarLinus Torvalds <torvalds@linux-foundation.org>
      c137381f
    • Linus Torvalds's avatar
      Merge tag 'scsi-misc' of git://git.kernel.org/pub/scm/linux/kernel/git/jejb/scsi · 7fcd473a
      Linus Torvalds authored
      Pull more SCSI updates from James Bottomley:
       "A few late arriving patches that missed the initial pull request. It's
        mostly bug fixes (the dt-bindings is a fix for the initial pull)"
      
      * tag 'scsi-misc' of git://git.kernel.org/pub/scm/linux/kernel/git/jejb/scsi:
        scsi: ufs: core: Remove unused function declaration
        scsi: target: docs: Remove tcm_mod_builder.py
        scsi: target: iblock: Quiet bool conversion warning with pr_preempt use
        scsi: dt-bindings: ufs: qcom: Fix ICE phandle
        scsi: core: Simplify scsi_cdl_check_cmd()
        scsi: isci: Fix comment typo
        scsi: smartpqi: Replace one-element arrays with flexible-array members
        scsi: target: tcmu: Replace strlcpy() with strscpy()
        scsi: ncr53c8xx: Replace strlcpy() with strscpy()
        scsi: lpfc: Fix lpfc_name struct packing
      7fcd473a
    • Linus Torvalds's avatar
      Merge tag 'i2c-for-6.5-rc1-part2' of git://git.kernel.org/pub/scm/linux/kernel/git/wsa/linux · 84dc5aa3
      Linus Torvalds authored
      Pull more i2c updates from Wolfram Sang:
      
       - xiic patch should have been in the original pull but slipped through
      
       - mpc patch fixes a build regression
      
       - nomadik cleanup
      
      * tag 'i2c-for-6.5-rc1-part2' of git://git.kernel.org/pub/scm/linux/kernel/git/wsa/linux:
        i2c: mpc: Drop unused variable
        i2c: nomadik: Remove a useless call in the remove function
        i2c: xiic: Don't try to handle more interrupt events after error
      84dc5aa3
    • Linus Torvalds's avatar
      Merge tag 'hardening-v6.5-rc1-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/kees/linux · 8fc3b8f0
      Linus Torvalds authored
      Pull hardening fixes from Kees Cook:
      
       - Check for NULL bdev in LoadPin (Matthias Kaehlcke)
      
       - Revert unwanted KUnit FORTIFY build default
      
       - Fix 1-element array causing boot warnings with xhci-hub
      
      * tag 'hardening-v6.5-rc1-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/kees/linux:
        usb: ch9: Replace bmSublinkSpeedAttr 1-element array with flexible array
        Revert "fortify: Allow KUnit test to build without FORTIFY"
        dm: verity-loadpin: Add NULL pointer check for 'bdev' parameter
      8fc3b8f0
    • Anup Sharma's avatar
      ntb: hw: amd: Fix debugfs_create_dir error checking · bff6efc5
      Anup Sharma authored
      The debugfs_create_dir function returns ERR_PTR in case of error, and the
      only correct way to check if an error occurred is 'IS_ERR' inline function.
      This patch will replace the null-comparison with IS_ERR.
      Signed-off-by: default avatarAnup Sharma <anupnewsmail@gmail.com>
      Suggested-by: default avatarIvan Orlov <ivan.orlov0322@gmail.com>
      Signed-off-by: default avatarJon Mason <jdmason@kudzu.us>
      bff6efc5
    • Linus Torvalds's avatar
      Merge tag 'perf-tools-for-v6.5-2-2023-07-06' of... · c206353d
      Linus Torvalds authored
      Merge tag 'perf-tools-for-v6.5-2-2023-07-06' of git://git.kernel.org/pub/scm/linux/kernel/git/perf/perf-tools-next
      
      Pull more perf tools updates from Namhyung Kim:
       "These are remaining changes and fixes for this cycle.
      
        Build:
      
         - Allow generating vmlinux.h from BTF using `make GEN_VMLINUX_H=1`
           and skip if the vmlinux has no BTF.
      
         - Replace deprecated clang -target xxx option by --target=xxx.
      
        perf record:
      
         - Print event attributes with well known type and config symbols in
           the debug output like below:
      
             # perf record -e cycles,cpu-clock -C0 -vv true
             <SNIP>
             ------------------------------------------------------------
             perf_event_attr:
               type                             0 (PERF_TYPE_HARDWARE)
               size                             136
               config                           0 (PERF_COUNT_HW_CPU_CYCLES)
               { sample_period, sample_freq }   4000
               sample_type                      IP|TID|TIME|CPU|PERIOD|IDENTIFIER
               read_format                      ID
               disabled                         1
               inherit                          1
               freq                             1
               sample_id_all                    1
               exclude_guest                    1
             ------------------------------------------------------------
             sys_perf_event_open: pid -1  cpu 0  group_fd -1  flags 0x8 = 5
             ------------------------------------------------------------
             perf_event_attr:
               type                             1 (PERF_TYPE_SOFTWARE)
               size                             136
               config                           0 (PERF_COUNT_SW_CPU_CLOCK)
               { sample_period, sample_freq }   4000
               sample_type                      IP|TID|TIME|CPU|PERIOD|IDENTIFIER
               read_format                      ID
               disabled                         1
               inherit                          1
               freq                             1
               sample_id_all                    1
               exclude_guest                    1
      
         - Update AMD IBS event error message since it now support per-process
           profiling but no priviledge filters.
      
             $ sudo perf record -e ibs_op//k -C 0
             Error:
             AMD IBS doesn't support privilege filtering. Try again without
             the privilege modifiers (like 'k') at the end.
      
        perf lock contention:
      
         - Support CSV style output using -x option
      
             $ sudo perf lock con -ab -x, sleep 1
             # output: contended, total wait, max wait, avg wait, type, caller
             19, 194232, 21415, 10222, spinlock, process_one_work+0x1f0
             15, 162748, 23843, 10849, rwsem:R, do_user_addr_fault+0x40e
             4, 86740, 23415, 21685, rwlock:R, ep_poll_callback+0x2d
             1, 84281, 84281, 84281, mutex, iwl_mvm_async_handlers_wk+0x135
             8, 67608, 27404, 8451, spinlock, __queue_work+0x174
             3, 58616, 31125, 19538, rwsem:W, do_mprotect_pkey+0xff
             3, 52953, 21172, 17651, rwlock:W, do_epoll_wait+0x248
             2, 30324, 19704, 15162, rwsem:R, do_madvise+0x3ad
             1, 24619, 24619, 24619, spinlock, rcu_core+0xd4
      
         - Add --output option to save the data to a file not to be interfered
           by other debug messages.
      
        Test:
      
         - Fix event parsing test on ARM where there's no raw PMU nor supports
           PERF_PMU_CAP_EXTENDED_HW_TYPE.
      
         - Update the lock contention test case for CSV output.
      
         - Fix a segfault in the daemon command test.
      
        Vendor events (JSON):
      
         - Add has_event() to check if the given event is available on system
           at runtime. On Intel machines, some transaction events may not be
           present when TSC extensions are disabled.
      
         - Update Intel event metrics.
      
        Misc:
      
         - Sort symbols by name using an external array of pointers instead of
           a rbtree node in the symbol. This will save 16-bytes or 24-bytes
           per symbol whether the sorting is actually requested or not.
      
         - Fix unwinding DWARF callstacks using libdw when --symfs option is
           used"
      
      * tag 'perf-tools-for-v6.5-2-2023-07-06' of git://git.kernel.org/pub/scm/linux/kernel/git/perf/perf-tools-next: (38 commits)
        perf test: Fix event parsing test when PERF_PMU_CAP_EXTENDED_HW_TYPE isn't supported.
        perf test: Fix event parsing test on Arm
        perf evsel amd: Fix IBS error message
        perf: unwind: Fix symfs with libdw
        perf symbol: Fix uninitialized return value in symbols__find_by_name()
        perf test: Test perf lock contention CSV output
        perf lock contention: Add --output option
        perf lock contention: Add -x option for CSV style output
        perf lock: Remove stale comments
        perf vendor events intel: Update tigerlake to 1.13
        perf vendor events intel: Update skylakex to 1.31
        perf vendor events intel: Update skylake to 57
        perf vendor events intel: Update sapphirerapids to 1.14
        perf vendor events intel: Update icelakex to 1.21
        perf vendor events intel: Update icelake to 1.19
        perf vendor events intel: Update cascadelakex to 1.19
        perf vendor events intel: Update meteorlake to 1.03
        perf vendor events intel: Add rocketlake events/metrics
        perf vendor metrics intel: Make transaction metrics conditional
        perf jevents: Support for has_event function
        ...
      c206353d
    • Linus Torvalds's avatar
      Merge tag 'bitmap-6.5-rc1' of https://github.com/norov/linux · ad8258e8
      Linus Torvalds authored
      Pull bitmap updates from Yury Norov:
       "Fixes for different bitmap pieces:
      
         - lib/test_bitmap: increment failure counter properly
      
           The tests that don't use expect_eq() macro to determine that a test
           is failured must increment failed_tests explicitly.
      
         - lib/bitmap: drop optimization of bitmap_{from,to}_arr64
      
           bitmap_{from,to}_arr64() optimization is overly optimistic
           on 32-bit LE architectures when it's wired to
           bitmap_copy_clear_tail().
      
         - nodemask: Drop duplicate check in for_each_node_mask()
      
           As the return value type of first_node() became unsigned, the node
           >= 0 became unnecessary.
      
         - cpumask: fix function description kernel-doc notation
      
         - MAINTAINERS: Add bits.h and bitfield.h to the BITMAP API record
      
           Add linux/bits.h and linux/bitfield.h for visibility"
      
      * tag 'bitmap-6.5-rc1' of https://github.com/norov/linux:
        MAINTAINERS: Add bitfield.h to the BITMAP API record
        MAINTAINERS: Add bits.h to the BITMAP API record
        cpumask: fix function description kernel-doc notation
        nodemask: Drop duplicate check in for_each_node_mask()
        lib/bitmap: drop optimization of bitmap_{from,to}_arr64
        lib/test_bitmap: increment failure counter properly
      ad8258e8
    • Geert Uytterhoeven's avatar
      lib: dhry: fix sleeping allocations inside non-preemptable section · 8ba388c0
      Geert Uytterhoeven authored
      The Smatch static checker reports the following warnings:
      
          lib/dhry_run.c:38 dhry_benchmark() warn: sleeping in atomic context
          lib/dhry_run.c:43 dhry_benchmark() warn: sleeping in atomic context
      
      Indeed, dhry() does sleeping allocations inside the non-preemptable
      section delimited by get_cpu()/put_cpu().
      
      Fix this by using atomic allocations instead.
      Add error handling, as atomic these allocations may fail.
      
      Link: https://lkml.kernel.org/r/bac6d517818a7cd8efe217c1ad649fffab9cc371.1688568764.git.geert+renesas@glider.be
      Fixes: 13684e96 ("lib: dhry: fix unstable smp_processor_id(_) usage")
      Reported-by: default avatarDan Carpenter <dan.carpenter@linaro.org>
      Closes: https://lore.kernel.org/r/0469eb3a-02eb-4b41-b189-de20b931fa56@moroto.mountainSigned-off-by: default avatarGeert Uytterhoeven <geert+renesas@glider.be>
      Signed-off-by: default avatarAndrew Morton <akpm@linux-foundation.org>
      8ba388c0
    • Andrey Konovalov's avatar
      kasan, slub: fix HW_TAGS zeroing with slub_debug · fdb54d96
      Andrey Konovalov authored
      Commit 946fa0db ("mm/slub: extend redzone check to extra allocated
      kmalloc space than requested") added precise kmalloc redzone poisoning to
      the slub_debug functionality.
      
      However, this commit didn't account for HW_TAGS KASAN fully initializing
      the object via its built-in memory initialization feature.  Even though
      HW_TAGS KASAN memory initialization contains special memory initialization
      handling for when slub_debug is enabled, it does not account for in-object
      slub_debug redzones.  As a result, HW_TAGS KASAN can overwrite these
      redzones and cause false-positive slub_debug reports.
      
      To fix the issue, avoid HW_TAGS KASAN memory initialization when
      slub_debug is enabled altogether.  Implement this by moving the
      __slub_debug_enabled check to slab_post_alloc_hook.  Common slab code
      seems like a more appropriate place for a slub_debug check anyway.
      
      Link: https://lkml.kernel.org/r/678ac92ab790dba9198f9ca14f405651b97c8502.1688561016.git.andreyknvl@google.com
      Fixes: 946fa0db ("mm/slub: extend redzone check to extra allocated kmalloc space than requested")
      Signed-off-by: default avatarAndrey Konovalov <andreyknvl@google.com>
      Reported-by: default avatarWill Deacon <will@kernel.org>
      Acked-by: default avatarMarco Elver <elver@google.com>
      Cc: Mark Rutland <mark.rutland@arm.com>
      Cc: Alexander Potapenko <glider@google.com>
      Cc: Andrey Ryabinin <ryabinin.a.a@gmail.com>
      Cc: Catalin Marinas <catalin.marinas@arm.com>
      Cc: Christoph Lameter <cl@linux.com>
      Cc: David Rientjes <rientjes@google.com>
      Cc: Dmitry Vyukov <dvyukov@google.com>
      Cc: Feng Tang <feng.tang@intel.com>
      Cc: Hyeonggon Yoo <42.hyeyoo@gmail.com>
      Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com>
      Cc: kasan-dev@googlegroups.com
      Cc: Pekka Enberg <penberg@kernel.org>
      Cc: Peter Collingbourne <pcc@google.com>
      Cc: Roman Gushchin <roman.gushchin@linux.dev>
      Cc: Vincenzo Frascino <vincenzo.frascino@arm.com>
      Cc: Vlastimil Babka <vbabka@suse.cz>
      Cc: <stable@vger.kernel.org>
      Signed-off-by: default avatarAndrew Morton <akpm@linux-foundation.org>
      fdb54d96
    • Andrey Konovalov's avatar
      kasan: fix type cast in memory_is_poisoned_n · 05c56e7b
      Andrey Konovalov authored
      Commit bb6e04a1 ("kasan: use internal prototypes matching gcc-13
      builtins") introduced a bug into the memory_is_poisoned_n implementation:
      it effectively removed the cast to a signed integer type after applying
      KASAN_GRANULE_MASK.
      
      As a result, KASAN started failing to properly check memset, memcpy, and
      other similar functions.
      
      Fix the bug by adding the cast back (through an additional signed integer
      variable to make the code more readable).
      
      Link: https://lkml.kernel.org/r/8c9e0251c2b8b81016255709d4ec42942dcaf018.1688431866.git.andreyknvl@google.com
      Fixes: bb6e04a1 ("kasan: use internal prototypes matching gcc-13 builtins")
      Signed-off-by: default avatarAndrey Konovalov <andreyknvl@google.com>
      Cc: Alexander Potapenko <glider@google.com>
      Cc: Andrey Ryabinin <ryabinin.a.a@gmail.com>
      Cc: Arnd Bergmann <arnd@arndb.de>
      Cc: Dmitry Vyukov <dvyukov@google.com>
      Cc: Marco Elver <elver@google.com>
      Cc: <stable@vger.kernel.org>
      Signed-off-by: default avatarAndrew Morton <akpm@linux-foundation.org>
      05c56e7b