linux-stable.git/fs/nilfs2, branch v5.16

Merge branch 'akpm' (patches from Andrew)

2021-11-09T18:11:53+00:00

Merge more updates from Andrew Morton:
 "87 patches.

  Subsystems affected by this patch series: mm (pagecache and hugetlb),
  procfs, misc, MAINTAINERS, lib, checkpatch, binfmt, kallsyms, ramfs,
  init, codafs, nilfs2, hfs, crash_dump, signals, seq_file, fork,
  sysvfs, kcov, gdb, resource, selftests, and ipc"

* emailed patches from Andrew Morton : (87 commits)
  ipc/ipc_sysctl.c: remove fallback for !CONFIG_PROC_SYSCTL
  ipc: check checkpoint_restore_ns_capable() to modify C/R proc files
  selftests/kselftest/runner/run_one(): allow running non-executable files
  virtio-mem: disallow mapping virtio-mem memory via /dev/mem
  kernel/resource: disallow access to exclusive system RAM regions
  kernel/resource: clean up and optimize iomem_is_exclusive()
  scripts/gdb: handle split debug for vmlinux
  kcov: replace local_irq_save() with a local_lock_t
  kcov: avoid enable+disable interrupts if !in_task()
  kcov: allocate per-CPU memory on the relevant node
  Documentation/kcov: define `ip' in the example
  Documentation/kcov: include types.h in the example
  sysv: use BUILD_BUG_ON instead of runtime check
  kernel/fork.c: unshare(): use swap() to make code cleaner
  seq_file: fix passing wrong private data
  seq_file: move seq_escape() to a header
  signal: remove duplicate include in signal.h
  crash_dump: remove duplicate include in crash_dump.h
  crash_dump: fix boolreturn.cocci warning
  hfs/hfsplus: use WARN_ON for sanity check
  ...

nilfs2: remove filenames from file comments

2021-11-09T18:02:52+00:00

Remove filenames that are not particularly useful in file comments, and
suppress checkpatch warnings

  WARNING: It's generally not useful to have the filename in the file

Link: https://lkml.kernel.org/r/1635151862-11547-3-git-send-email-konishi.ryusuke@gmail.com
Signed-off-by: Ryusuke Konishi 
Cc: Qing Wang 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds

nilfs2: replace snprintf in show functions with sysfs_emit

2021-11-09T18:02:51+00:00

Patch series "nilfs2 updates".

This patch (of 2):

coccicheck complains about the use of snprintf() in sysfs show functions.

Fix the coccicheck warning:

  WARNING: use scnprintf or sprintf.

Use sysfs_emit instead of scnprintf or sprintf makes more sense.

Link: https://lkml.kernel.org/r/1635151862-11547-1-git-send-email-konishi.ryusuke@gmail.com
Link: https://lkml.kernel.org/r/1634095759-4625-1-git-send-email-wangqing@vivo.com
Link: https://lkml.kernel.org/r/1635151862-11547-2-git-send-email-konishi.ryusuke@gmail.com
Signed-off-by: Qing Wang 
Signed-off-by: Ryusuke Konishi 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds

nilfs2: use bdev_nr_bytes instead of open coding it

2021-10-18T20:43:23+00:00

Use the proper helper to read the block device size.

Signed-off-by: Christoph Hellwig 
Reviewed-by: Kees Cook 
Acked-by: Ryusuke Konishi 
Link: https://lore.kernel.org/r/20211018101130.1838532-20-hch@lst.de
Signed-off-by: Jens Axboe

Merge branch 'akpm' (patches from Andrew)

2021-09-08T19:55:35+00:00

Merge more updates from Andrew Morton:
 "147 patches, based on 7d2a07b769330c34b4deabeed939325c77a7ec2f.

  Subsystems affected by this patch series: mm (memory-hotplug, rmap,
  ioremap, highmem, cleanups, secretmem, kfence, damon, and vmscan),
  alpha, percpu, procfs, misc, core-kernel, MAINTAINERS, lib,
  checkpatch, epoll, init, nilfs2, coredump, fork, pids, criu, kconfig,
  selftests, ipc, and scripts"

* emailed patches from Andrew Morton : (94 commits)
  scripts: check_extable: fix typo in user error message
  mm/workingset: correct kernel-doc notations
  ipc: replace costly bailout check in sysvipc_find_ipc()
  selftests/memfd: remove unused variable
  Kconfig.debug: drop selecting non-existing HARDLOCKUP_DETECTOR_ARCH
  configs: remove the obsolete CONFIG_INPUT_POLLDEV
  prctl: allow to setup brk for et_dyn executables
  pid: cleanup the stale comment mentioning pidmap_init().
  kernel/fork.c: unexport get_{mm,task}_exe_file
  coredump: fix memleak in dump_vma_snapshot()
  fs/coredump.c: log if a core dump is aborted due to changed file permissions
  nilfs2: use refcount_dec_and_lock() to fix potential UAF
  nilfs2: fix memory leak in nilfs_sysfs_delete_snapshot_group
  nilfs2: fix memory leak in nilfs_sysfs_create_snapshot_group
  nilfs2: fix memory leak in nilfs_sysfs_delete_##name##_group
  nilfs2: fix memory leak in nilfs_sysfs_create_##name##_group
  nilfs2: fix NULL pointer in nilfs_##name##_attr_release
  nilfs2: fix memory leak in nilfs_sysfs_create_device_group
  trap: cleanup trap_init()
  init: move usermodehelper_enable() to populate_rootfs()
  ...

nilfs2: use refcount_dec_and_lock() to fix potential UAF

2021-09-08T18:50:27+00:00

When the refcount is decreased to 0, the resource reclamation branch is
entered.  Before CPU0 reaches the race point (1), CPU1 may obtain the
spinlock and traverse the rbtree to find 'root', see
nilfs_lookup_root().

Although CPU1 will call refcount_inc() to increase the refcount, it is
obviously too late.  CPU0 will release 'root' directly, CPU1 then
accesses 'root' and triggers UAF.

Use refcount_dec_and_lock() to ensure that both the operations of
decrease refcount to 0 and link deletion are lock protected eliminates
this risk.

	     CPU0                      CPU1
	nilfs_put_root():
		    <-------- (1)
				spin_lock(&nilfs->ns_cptree_lock);
				rb_erase(&root->rb_node, &nilfs->ns_cptree);
				spin_unlock(&nilfs->ns_cptree_lock);

	kfree(root);
		    <-------- use-after-free

  refcount_t: underflow; use-after-free.
  WARNING: CPU: 2 PID: 9476 at lib/refcount.c:28 \
  refcount_warn_saturate+0x1cf/0x210 lib/refcount.c:28
  Modules linked in:
  CPU: 2 PID: 9476 Comm: syz-executor.0 Not tainted 5.10.45-rc1+ #3
  Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), ...
  RIP: 0010:refcount_warn_saturate+0x1cf/0x210 lib/refcount.c:28
  ... ...
  Call Trace:
     __refcount_sub_and_test include/linux/refcount.h:283 [inline]
     __refcount_dec_and_test include/linux/refcount.h:315 [inline]
     refcount_dec_and_test include/linux/refcount.h:333 [inline]
     nilfs_put_root+0xc1/0xd0 fs/nilfs2/the_nilfs.c:795
     nilfs_segctor_destroy fs/nilfs2/segment.c:2749 [inline]
     nilfs_detach_log_writer+0x3fa/0x570 fs/nilfs2/segment.c:2812
     nilfs_put_super+0x2f/0xf0 fs/nilfs2/super.c:467
     generic_shutdown_super+0xcd/0x1f0 fs/super.c:464
     kill_block_super+0x4a/0x90 fs/super.c:1446
     deactivate_locked_super+0x6a/0xb0 fs/super.c:335
     deactivate_super+0x85/0x90 fs/super.c:366
     cleanup_mnt+0x277/0x2e0 fs/namespace.c:1118
     __cleanup_mnt+0x15/0x20 fs/namespace.c:1125
     task_work_run+0x8e/0x110 kernel/task_work.c:151
     tracehook_notify_resume include/linux/tracehook.h:188 [inline]
     exit_to_user_mode_loop kernel/entry/common.c:164 [inline]
     exit_to_user_mode_prepare+0x13c/0x170 kernel/entry/common.c:191
     syscall_exit_to_user_mode+0x16/0x30 kernel/entry/common.c:266
     do_syscall_64+0x45/0x80 arch/x86/entry/common.c:56
     entry_SYSCALL_64_after_hwframe+0x44/0xa9

There is no reproduction program, and the above is only theoretical
analysis.

Link: https://lkml.kernel.org/r/1629859428-5906-1-git-send-email-konishi.ryusuke@gmail.com
Fixes: ba65ae4729bf ("nilfs2: add checkpoint tree to nilfs object")
Link: https://lkml.kernel.org/r/20210723012317.4146-1-thunder.leizhen@huawei.com
Signed-off-by: Zhen Lei 
Signed-off-by: Ryusuke Konishi 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds

nilfs2: fix memory leak in nilfs_sysfs_delete_snapshot_group

2021-09-08T18:50:27+00:00

kobject_put() should be used to cleanup the memory associated with the
kobject instead of kobject_del().  See the section "Kobject removal" of
"Documentation/core-api/kobject.rst".

Link: https://lkml.kernel.org/r/20210629022556.3985106-7-sunnanyong@huawei.com
Link: https://lkml.kernel.org/r/1625651306-10829-7-git-send-email-konishi.ryusuke@gmail.com
Signed-off-by: Nanyong Sun 
Signed-off-by: Ryusuke Konishi 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds

nilfs2: fix memory leak in nilfs_sysfs_create_snapshot_group

2021-09-08T18:50:27+00:00

If kobject_init_and_add returns with error, kobject_put() is needed here
to avoid memory leak, because kobject_init_and_add may return error
without freeing the memory associated with the kobject it allocated.

Link: https://lkml.kernel.org/r/20210629022556.3985106-6-sunnanyong@huawei.com
Link: https://lkml.kernel.org/r/1625651306-10829-6-git-send-email-konishi.ryusuke@gmail.com
Signed-off-by: Nanyong Sun 
Signed-off-by: Ryusuke Konishi 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds

nilfs2: fix memory leak in nilfs_sysfs_delete_##name##_group

2021-09-08T18:50:27+00:00

The kobject_put() should be used to cleanup the memory associated with the
kobject instead of kobject_del.  See the section "Kobject removal" of
"Documentation/core-api/kobject.rst".

Link: https://lkml.kernel.org/r/20210629022556.3985106-5-sunnanyong@huawei.com
Link: https://lkml.kernel.org/r/1625651306-10829-5-git-send-email-konishi.ryusuke@gmail.com
Signed-off-by: Nanyong Sun 
Signed-off-by: Ryusuke Konishi 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds

nilfs2: fix memory leak in nilfs_sysfs_create_##name##_group

2021-09-08T18:50:27+00:00

If kobject_init_and_add return with error, kobject_put() is needed here to
avoid memory leak, because kobject_init_and_add may return error without
freeing the memory associated with the kobject it allocated.

Link: https://lkml.kernel.org/r/20210629022556.3985106-4-sunnanyong@huawei.com
Link: https://lkml.kernel.org/r/1625651306-10829-4-git-send-email-konishi.ryusuke@gmail.com
Signed-off-by: Nanyong Sun 
Signed-off-by: Ryusuke Konishi 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds