No description
  • C 98.2%
  • Assembly 1%
  • Makefile 0.3%
  • Shell 0.2%
  • Python 0.1%
Find a file
Repository files (latest commit first)
Filename Latest commit message Latest commit date
Ethan Lien 44277c50fd btrfs: fix qgroup reserve overflow the qgroup limit
commit b642b52d0b50f4d398cb4293f64992d0eed2e2ce upstream.

We use extent_changeset->bytes_changed in qgroup_reserve_data() to record
how many bytes we set for EXTENT_QGROUP_RESERVED state. Currently the
bytes_changed is set as "unsigned int", and it will overflow if we try to
fallocate a range larger than 4GiB. The result is we reserve less bytes
and eventually break the qgroup limit.

Unlike regular buffered/direct write, which we use one changeset for
each ordered extent, which can never be larger than 256M.  For
fallocate, we use one changeset for the whole range, thus it no longer
respects the 256M per extent limit, and caused the problem.

The following example test script reproduces the problem:

  $ cat qgroup-overflow.sh
  #!/bin/bash

  DEV=/dev/sdj
  MNT=/mnt/sdj

  mkfs.btrfs -f $DEV
  mount $DEV $MNT

  # Set qgroup limit to 2GiB.
  btrfs quota enable $MNT
  btrfs qgroup limit 2G $MNT

  # Try to fallocate a 3GiB file. This should fail.
  echo
  echo "Try to fallocate a 3GiB file..."
  fallocate -l 3G $MNT/3G.file

  # Try to fallocate a 5GiB file.
  echo
  echo "Try to fallocate a 5GiB file..."
  fallocate -l 5G $MNT/5G.file

  # See we break the qgroup limit.
  echo
  sync
  btrfs qgroup show -r $MNT

  umount $MNT

When running the test:

  $ ./qgroup-overflow.sh
  (...)

  Try to fallocate a 3GiB file...
  fallocate: fallocate failed: Disk quota exceeded

  Try to fallocate a 5GiB file...

  qgroupid         rfer         excl     max_rfer
  --------         ----         ----     --------
  0/5           5.00GiB      5.00GiB      2.00GiB

Since we have no control of how bytes_changed is used, it's better to
set it to u64.

CC: stable@vger.kernel.org # 4.14+
Reviewed-by: Qu Wenruo <wqu@suse.com>
Signed-off-by: Ethan Lien <ethanlien@synology.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2022-04-15 14:18:39 +02:00
arch x86/speculation: Restore speculation related MSRs during S3 resume 2022-04-15 14:18:39 +02:00
block Revert "Revert "block, bfq: honor already-setup queue merges"" 2022-04-15 14:18:23 +02:00
certs
crypto
Documentation dt-bindings: spi: mxic: The interrupt property is not mandatory 2022-04-15 14:18:30 +02:00
drivers mmc: renesas_sdhi: don't overwrite TAP settings when HS400 tuning is complete 2022-04-15 14:18:39 +02:00
fs btrfs: fix qgroup reserve overflow the qgroup limit 2022-04-15 14:18:39 +02:00
include NFS: swap IO handling is slightly different for O_DIRECT IO 2022-04-15 14:18:35 +02:00
init init/main.c: return 1 from handled __setup() functions 2022-04-15 14:18:35 +02:00
ipc
kernel
lib lz4: fix LZ4_decompress_safe_partial read out of bound 2022-04-15 14:18:39 +02:00
LICENSES
mm mm/mempolicy: fix mpol_new leak in shared_policy_replace 2022-04-15 14:18:39 +02:00
net SUNRPC: Handle low memory situations in call_status() 2022-04-15 14:18:38 +02:00
samples
scripts gcc-plugins/stackleak: Exactly match strings instead of prefixes 2022-04-15 14:18:22 +02:00
security Fix incorrect type in assignment of ipv6 port for audit 2022-04-15 14:18:22 +02:00
sound ASoC: topology: Allow TLV control to be either read or write 2022-04-15 14:18:30 +02:00
tools perf session: Remap buf if there is no space for event 2022-04-15 14:18:38 +02:00
usr
virt KVM: Prevent module exit until all VMs are freed 2022-04-15 14:18:27 +02:00
.clang-format
.cocciconfig
.get_maintainer.ignore
.gitattributes
.gitignore
.mailmap
COPYING
CREDITS
Kbuild
Kconfig
MAINTAINERS
Makefile
README

Linux kernel
============

There are several guides for kernel developers and users. These guides can
be rendered in a number of formats, like HTML and PDF. Please read
Documentation/admin-guide/README.rst first.

In order to build the documentation, use ``make htmldocs`` or
``make pdfdocs``.  The formatted documentation can also be read online at:

    https://www.kernel.org/doc/html/latest/

There are various text files in the Documentation/ subdirectory,
several of them using the Restructured Text markup notation.

Please read the Documentation/process/changes.rst file, as it contains the
requirements for building and running the kernel, and information about
the problems which may result by upgrading your kernel.