On 32-bit:

    fs/pstore/blk.c: In function ‘__best_effort_init’:
    include/linux/kern_levels.h:5:18: warning: format ‘%zu’ expects argument of type ‘size_t’, but argument 3 has type ‘long unsigned int’ [-Wformat=]
	5 | #define KERN_SOH "\001"  /* ASCII Start Of Header */
	  |                  ^~~~~~
    include/linux/kern_levels.h:14:19: note: in expansion of macro ‘KERN_SOH’
       14 | #define KERN_INFO KERN_SOH "6" /* informational */
	  |                   ^~~~~~~~
    include/linux/printk.h:373:9: note: in expansion of macro ‘KERN_INFO’
      373 |  printk(KERN_INFO pr_fmt(fmt), ##__VA_ARGS__)
	  |         ^~~~~~~~~
    fs/pstore/blk.c:314:3: note: in expansion of macro ‘pr_info’
      314 |   pr_info("attached %s (%zu) (no dedicated panic_write!)\n",
	  |   ^~~~~~~

Cc: stable@vger.kernel.org
Fixes: 7bb9557b48fcabaa ("pstore/blk: Use the normal block device I/O path")
Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org>
Signed-off-by: Kees Cook <keescook@chromium.org>
Link: https://lore.kernel.org/r/20210629103700.1935012-1-geert@linux-m68k.org
Cc: Jens Axboe <axboe@kernel.dk>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

Merge misc fixes from Andrew Morton:
 "15 patches.

  Subsystems affected by this patch series: ipc, hexagon, mm (swap,
  slab-generic, kmemleak, hugetlb, kasan, damon, and highmem), and proc"

* emailed patches from Andrew Morton <akpm@linux-foundation.org>:
  proc/vmcore: fix clearing user buffer by properly using clear_user()
  kmap_local: don't assume kmap PTEs are linear arrays in memory
  mm/damon/dbgfs: fix missed use of damon_dbgfs_lock
  mm/damon/dbgfs: use '__GFP_NOWARN' for user-specified size buffer allocation
  kasan: test: silence intentional read overflow warnings
  hugetlb, userfaultfd: fix reservation restore on userfaultfd error
  hugetlb: fix hugetlb cgroup refcounting during mremap
  mm: kmemleak: slob: respect SLAB_NOLEAKTRACE flag
  hexagon: ignore vmlinux.lds
  hexagon: clean up timer-regs.h
  hexagon: export raw I/O routines for modules
  mm: emit the "free" trace report before freeing memory in kmem_cache_free()
  shm: extend forced shm destroy to support objects from several IPC nses
  ipc: WARN if trying to remove ipc object which is absent
  mm/swap.c:put_pages_list(): reinitialise the page list

Pull block fixes from Jens Axboe:

 - Flip a cap check to avoid a selinux error (Alistair)

 - Fix for a regression this merge window where we can miss a queue ref
   put (me)

 - Un-mark pstore-blk as broken, as the condition that triggered that
   change has been rectified (Kees)

 - Queue quiesce and sync fixes (Ming)

 - FUA insertion fix (Ming)

 - blk-cgroup error path put fix (Yu)

* tag 'block-5.16-2021-11-19' of git://git.kernel.dk/linux-block:
  blk-mq: don't insert FUA request with data into scheduler queue
  blk-cgroup: fix missing put device in error path from blkg_conf_pref()
  block: avoid to quiesce queue in elevator_init_mq
  Revert "mark pstore-blk as broken"
  blk-mq: cancel blk-mq dispatch work in both blk_cleanup_queue and disk_release()
  block: fix missing queue put in error path
  block: Check ADMIN before NICE for IOPRIO_CLASS_RT

Pull cifs fixes from Steve French:
 "Three small cifs/smb3 fixes: two to address minor coverity issues and
  one cleanup"

* tag '5.16-rc1-smb3-fixes' of git://git.samba.org/sfrench/cifs-2.6:
  cifs: introduce cifs_ses_mark_for_reconnect() helper
  cifs: protect srv_count with cifs_tcp_ses_lock
  cifs: move debug print out of spinlock

To clear a user buffer we cannot simply use memset, we have to use
clear_user().  With a virtio-mem device that registers a vmcore_cb and
has some logically unplugged memory inside an added Linux memory block,
I can easily trigger a BUG by copying the vmcore via "cp":

  systemd[1]: Starting Kdump Vmcore Save Service...
  kdump[420]: Kdump is using the default log level(3).
  kdump[453]: saving to /sysroot/var/crash/127.0.0.1-2021-11-11-14:59:22/
  kdump[458]: saving vmcore-dmesg.txt to /sysroot/var/crash/127.0.0.1-2021-11-11-14:59:22/
  kdump[465]: saving vmcore-dmesg.txt complete
  kdump[467]: saving vmcore
  BUG: unable to handle page fault for address: 00007f2374e01000
  #PF: supervisor write access in kernel mode
  #PF: error_code(0x0003) - permissions violation
  PGD 7a523067 P4D 7a523067 PUD 7a528067 PMD 7a525067 PTE 800000007048f867
  Oops: 0003 [#1] PREEMPT SMP NOPTI
  CPU: 0 PID: 468 Comm: cp Not tainted 5.15.0+ #6
  Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS rel-1.14.0-27-g64f37cc530f1-prebuilt.qemu.org 04/01/2014
  RIP: 0010:read_from_oldmem.part.0.cold+0x1d/0x86
  Code: ff ff ff e8 05 ff fe ff e9 b9 e9 7f ff 48 89 de 48 c7 c7 38 3b 60 82 e8 f1 fe fe ff 83 fd 08 72 3c 49 8d 7d 08 4c 89 e9 89 e8 <49> c7 45 00 00 00 00 00 49 c7 44 05 f8 00 00 00 00 48 83 e7 f81
  RSP: 0018:ffffc9000073be08 EFLAGS: 00010212
  RAX: 0000000000001000 RBX: 00000000002fd000 RCX: 00007f2374e01000
  RDX: 0000000000000001 RSI: 00000000ffffdfff RDI: 00007f2374e01008
  RBP: 0000000000001000 R08: 0000000000000000 R09: ffffc9000073bc50
  R10: ffffc9000073bc48 R11: ffffffff829461a8 R12: 000000000000f000
  R13: 00007f2374e01000 R14: 0000000000000000 R15: ffff88807bd421e8
  FS:  00007f2374e12140(0000) GS:ffff88807f000000(0000) knlGS:0000000000000000
  CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
  CR2: 00007f2374e01000 CR3: 000000007a4aa000 CR4: 0000000000350eb0
  Call Trace:
   read_vmcore+0x236/0x2c0
   proc_reg_read+0x55/0xa0
   vfs_read+0x95/0x190
   ksys_read+0x4f/0xc0
   do_syscall_64+0x3b/0x90
   entry_SYSCALL_64_after_hwframe+0x44/0xae

Some x86-64 CPUs have a CPU feature called "Supervisor Mode Access
Prevention (SMAP)", which is used to detect wrong access from the kernel
to user buffers like this: SMAP triggers a permissions violation on
wrong access.  In the x86-64 variant of clear_user(), SMAP is properly
handled via clac()+stac().

To fix, properly use clear_user() when we're dealing with a user buffer.

Link: https://lkml.kernel.org/r/20211112092750.6921-1-david@redhat.com
Fixes: 997c136f518c ("fs/proc/vmcore.c: add hook to read_from_oldmem() to check for non-ram pages")
Signed-off-by: David Hildenbrand <david@redhat.com>
Acked-by: Baoquan He <bhe@redhat.com>
Cc: Dave Young <dyoung@redhat.com>
Cc: Baoquan He <bhe@redhat.com>
Cc: Vivek Goyal <vgoyal@redhat.com>
Cc: Philipp Rudo <prudo@redhat.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

Pull btrfs fixes from David Sterba:
 "Several xes and one old ioctl deprecation. Namely there's fix for
  crashes/warnings with lzo compression that was suspected to be caused
  by first pull merge resolution, but it was a different bug.

  Summary:

   - regression fix for a crash in lzo due to missing boundary checks of
     the page array

   - fix crashes on ARM64 due to missing barriers when synchronizing
     status bits between work queues

   - silence lockdep when reading chunk tree during mount

   - fix false positive warning in integrity checker on devices with
     disabled write caching

   - fix signedness of bitfields in scrub

   - start deprecation of balance v1 ioctl"

* tag 'for-5.16-rc1-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/kdave/linux:
  btrfs: deprecate BTRFS_IOC_BALANCE ioctl
  btrfs: make 1-bit bit-fields of scrub_page unsigned int
  btrfs: check-integrity: fix a warning on write caching disabled disk
  btrfs: silence lockdep when reading chunk tree during mount
  btrfs: fix memory ordering between normal and ordered work functions
  btrfs: fix a out-of-bound access in copy_compressed_data_to_page()

Pull UDF fix from Jan Kara:
 "A fix for a long-standing UDF bug where we were not properly
  validating directory position inside readdir"

* tag 'fs_for_v5.16-rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/jack/linux-fs:
  udf: Fix crash after seekdir

Pull setattr idmapping fix from Christian Brauner:
 "This contains a simple fix for setattr. When determining the validity
  of the attributes the ia_{g,u}id fields contain the value that will be
  written to inode->i_{g,u}id. When the {g,u}id attribute of the file
  isn't altered and the caller's fs{g,u}id matches the current {g,u}id
  attribute the attribute change is allowed.

  The value in ia_{g,u}id does already account for idmapped mounts and
  will have taken the relevant idmapping into account. So in order to
  verify that the {g,u}id attribute isn't changed we simple need to
  compare the ia_{g,u}id value against the inode's i_{g,u}id value.

  This only has any meaning for idmapped mounts as idmapping helpers are
  idempotent without them. And for idmapped mounts this really only has
  a meaning when circular idmappings are used, i.e. mappings where e.g.
  id 1000 is mapped to id 1001 and id 1001 is mapped to id 1000. Such
  ciruclar mappings can e.g. be useful when sharing the same home
  directory between multiple users at the same time.

  Before this patch we could end up denying legitimate attribute changes
  and allowing invalid attribute changes when circular mappings are
  used. To even get into this situation the caller must've been
  privileged both to create that mapping and to create that idmapped
  mount.

  This hasn't been seen in the wild anywhere but came up when expanding
  the fstest suite during work on a series of hardening patches. All
  idmapped fstests pass without any regressions and we're adding new
  tests to verify the behavior of circular mappings.

  The new tests can be found at [1]"

Link: https://lore.kernel.org/linux-fsdevel/20211109145713.1868404-2-brauner@kernel.org [1]

* tag 'fs.idmapped.v5.16-rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/brauner/linux:
  fs: handle circular mappings correctly

Pull gfs2 fixes from Andreas Gruenbacher:

 - The current iomap_file_buffered_write behavior of failing the entire
   write when part of the user buffer cannot be faulted in leads to an
   endless loop in gfs2. Work around that in gfs2 for now.

 - Various other bugs all over the place.

* tag 'gfs2-v5.16-rc2-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/gfs2/linux-gfs2:
  gfs2: Prevent endless loops in gfs2_file_buffered_write
  gfs2: Fix "Introduce flag for glock holder auto-demotion"
  gfs2: Fix length of holes reported at end-of-file
  gfs2: release iopen glock early in evict
  gfs2: Fix atomic bug in gfs2_instantiate
  gfs2: Only dereference i->iov when iter_is_iovec(i)

Pull nfsd bugfix from Bruce Fields:
 "This is just one bugfix for a buffer overflow in knfsd's xdr decoding"

* tag 'nfsd-5.16-1' of git://linux-nfs.org/~bfields/linux:
  NFSD: Fix exposure in nfsd4_decode_bitmap()