Commit Graph

329 Commits

Author SHA1 Message Date
Jan Kara
a4db1072e1 quota: Fix memory leak when handling corrupted quota file
When checking corrupted quota file we can bail out and leak allocated
info structure. Properly free info structure on error return.

Reported-by: syzbot+77779c9b52ab78154b08@syzkaller.appspotmail.com
Fixes: 11c514a99b ("quota: Sanity-check quota file headers on load")
Signed-off-by: Jan Kara <jack@suse.cz>
2021-01-05 14:42:18 +01:00
Linus Torvalds
b97d4c424e \n
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Merge tag 'for_v5.11-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/jack/linux-fs

Pull ext2, reiserfs, quota and writeback updates from Jan Kara:

 - a couple of quota fixes (mostly for problems found by syzbot)

 - several ext2 cleanups

 - one fix for reiserfs crash on corrupted image

 - a fix for spurious warning in writeback code

* tag 'for_v5.11-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/jack/linux-fs:
  writeback: don't warn on an unregistered BDI in __mark_inode_dirty
  fs: quota: fix array-index-out-of-bounds bug by passing correct argument to vfs_cleanup_quota_inode()
  reiserfs: add check for an invalid ih_entry_count
  ext2: Fix fall-through warnings for Clang
  fs/ext2: Use ext2_put_page
  docs: filesystems: Reduce ext2.rst to one top-level heading
  quota: Sanity-check quota file headers on load
  quota: Don't overflow quota file offsets
  ext2: Remove unnecessary blank
  fs/quota: update quota state flags scheme with project quota flags
2020-12-17 11:00:37 -08:00
Anant Thazhemadam
e51d68e76d fs: quota: fix array-index-out-of-bounds bug by passing correct argument to vfs_cleanup_quota_inode()
When dquot_resume() was last updated, the argument that got passed
to vfs_cleanup_quota_inode was incorrectly set.

If type = -1 and dquot_load_quota_sb() returns a negative value,
then vfs_cleanup_quota_inode() gets called with -1 passed as an
argument, and this leads to an array-index-out-of-bounds bug.

Fix this issue by correctly passing the arguments.

Fixes: ae45f07d47 ("quota: Simplify dquot_resume()")
Link: https://lore.kernel.org/r/20201208194338.7064-1-anant.thazhemadam@gmail.com
Reported-by: syzbot+2643e825238d7aabb37f@syzkaller.appspotmail.com
Tested-by: syzbot+2643e825238d7aabb37f@syzkaller.appspotmail.com
CC: stable@vger.kernel.org
Signed-off-by: Anant Thazhemadam <anant.thazhemadam@gmail.com>
Signed-off-by: Jan Kara <jack@suse.cz>
2020-12-09 10:07:10 +01:00
Christoph Hellwig
4e7b5671c6 block: remove i_bdev
Switch the block device lookup interfaces to directly work with a dev_t
so that struct block_device references are only acquired by the
blkdev_get variants (and the blk-cgroup special case).  This means that
we now don't need an extra reference in the inode and can generally
simplify handling of struct block_device to keep the lookups contained
in the core block layer code.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Jan Kara <jack@suse.cz>
Reviewed-by: Hannes Reinecke <hare@suse.de>
Acked-by: Tejun Heo <tj@kernel.org>
Acked-by: Coly Li <colyli@suse.de>		[bcache]
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2020-12-01 14:53:39 -07:00
Christoph Hellwig
60b498852b fs: remove get_super_thawed and get_super_exclusive_thawed
Just open code the wait in the only caller of both functions.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Jan Kara <jack@suse.cz>
Reviewed-by: Hannes Reinecke <hare@suse.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2020-12-01 14:53:38 -07:00
Jan Kara
11c514a99b quota: Sanity-check quota file headers on load
Perform basic sanity checks of quota headers to avoid kernel crashes on
corrupted quota files.

CC: stable@vger.kernel.org
Reported-by: syzbot+f816042a7ae2225f25ba@syzkaller.appspotmail.com
Reviewed-by: Andreas Dilger <adilger@dilger.ca>
Signed-off-by: Jan Kara <jack@suse.cz>
2020-11-03 11:17:00 +01:00
Jan Kara
10f04d40a9 quota: Don't overflow quota file offsets
The on-disk quota format supports quota files with upto 2^32 blocks. Be
careful when computing quota file offsets in the quota files from block
numbers as they can overflow 32-bit types. Since quota files larger than
4GB would require ~26 millions of quota users, this is mostly a
theoretical concern now but better be careful, fuzzers would find the
problem sooner or later anyway...

Reviewed-by: Andreas Dilger <adilger@dilger.ca>
Signed-off-by: Jan Kara <jack@suse.cz>
2020-11-03 11:17:00 +01:00
Linus Torvalds
b77a69b81c \n
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Merge tag 'fs_for_v5.10-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/jack/linux-fs

Pull UDF, reiserfs, ext2, quota fixes from Jan Kara:

 - a couple of UDF fixes for issues found by syzbot fuzzing

 - a couple of reiserfs fixes for issues found by syzbot fuzzing

 - some minor ext2 cleanups

 - quota patches to support grace times beyond year 2038 for XFS quota
   APIs

* tag 'fs_for_v5.10-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/jack/linux-fs:
  reiserfs: Fix oops during mount
  udf: Limit sparing table size
  udf: Remove pointless union in udf_inode_info
  udf: Avoid accessing uninitialized data on failed inode read
  quota: clear padding in v2r1_mem2diskdqb()
  reiserfs: Initialize inode keys properly
  udf: Fix memory leak when mounting
  udf: Remove redundant initialization of variable ret
  reiserfs: only call unlock_new_inode() if I_NEW
  ext2: Fix some kernel-doc warnings in balloc.c
  quota: Expand comment describing d_itimer
  quota: widen timestamps for the fs_disk_quota structure
  reiserfs: Fix memory leak in reiserfs_parse_options()
  udf: Use kvzalloc() in udf_sb_alloc_bitmap()
  ext2: remove duplicate include
2020-10-15 14:56:15 -07:00
Linus Torvalds
e18afa5bfa Merge branch 'work.quota-compat' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs
Pull compat quotactl cleanups from Al Viro:
 "More Christoph's compat cleanups: quotactl(2)"

* 'work.quota-compat' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs:
  quota: simplify the quotactl compat handling
  compat: add a compat_need_64bit_alignment_fixup() helper
  compat: lift compat_s64 and compat_u64 to <asm-generic/compat.h>
2020-10-12 16:37:13 -07:00
Eric Dumazet
3d3dc274ce quota: clear padding in v2r1_mem2diskdqb()
Freshly allocated memory contains garbage, better make sure
to init all struct v2r1_disk_dqblk fields to avoid KMSAN report:

BUG: KMSAN: uninit-value in qtree_entry_unused+0x137/0x1b0 fs/quota/quota_tree.c:218
CPU: 0 PID: 23373 Comm: syz-executor.1 Not tainted 5.9.0-rc4-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Call Trace:
 __dump_stack lib/dump_stack.c:77 [inline]
 dump_stack+0x21c/0x280 lib/dump_stack.c:118
 kmsan_report+0xf7/0x1e0 mm/kmsan/kmsan_report.c:122
 __msan_warning+0x58/0xa0 mm/kmsan/kmsan_instr.c:219
 qtree_entry_unused+0x137/0x1b0 fs/quota/quota_tree.c:218
 v2r1_mem2diskdqb+0x43d/0x710 fs/quota/quota_v2.c:285
 qtree_write_dquot+0x226/0x870 fs/quota/quota_tree.c:394
 v2_write_dquot+0x1ad/0x280 fs/quota/quota_v2.c:333
 dquot_commit+0x4af/0x600 fs/quota/dquot.c:482
 ext4_write_dquot fs/ext4/super.c:5934 [inline]
 ext4_mark_dquot_dirty+0x4d8/0x6a0 fs/ext4/super.c:5985
 mark_dquot_dirty fs/quota/dquot.c:347 [inline]
 mark_all_dquot_dirty fs/quota/dquot.c:385 [inline]
 dquot_alloc_inode+0xc05/0x12b0 fs/quota/dquot.c:1755
 __ext4_new_inode+0x8204/0x9d70 fs/ext4/ialloc.c:1155
 ext4_tmpfile+0x41a/0x850 fs/ext4/namei.c:2686
 vfs_tmpfile+0x2a2/0x570 fs/namei.c:3283
 do_tmpfile fs/namei.c:3316 [inline]
 path_openat+0x4035/0x6a90 fs/namei.c:3359
 do_filp_open+0x2b8/0x710 fs/namei.c:3395
 do_sys_openat2+0xa88/0x1140 fs/open.c:1168
 do_sys_open fs/open.c:1184 [inline]
 __do_compat_sys_openat fs/open.c:1242 [inline]
 __se_compat_sys_openat+0x2a4/0x310 fs/open.c:1240
 __ia32_compat_sys_openat+0x56/0x70 fs/open.c:1240
 do_syscall_32_irqs_on arch/x86/entry/common.c:80 [inline]
 __do_fast_syscall_32+0x129/0x180 arch/x86/entry/common.c:139
 do_fast_syscall_32+0x6a/0xc0 arch/x86/entry/common.c:162
 do_SYSENTER_32+0x73/0x90 arch/x86/entry/common.c:205
 entry_SYSENTER_compat_after_hwframe+0x4d/0x5c
RIP: 0023:0xf7ff4549
Code: b8 01 10 06 03 74 b4 01 10 07 03 74 b0 01 10 08 03 74 d8 01 00 00 00 00 00 00 00 00 00 00 00 00 00 51 52 55 89 e5 0f 34 cd 80 <5d> 5a 59 c3 90 90 90 90 eb 0d 90 90 90 90 90 90 90 90 90 90 90 90
RSP: 002b:00000000f55cd0cc EFLAGS: 00000296 ORIG_RAX: 0000000000000127
RAX: ffffffffffffffda RBX: 00000000ffffff9c RCX: 0000000020000000
RDX: 0000000000410481 RSI: 0000000000000000 RDI: 0000000000000000
RBP: 0000000000000000 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000000 R12: 0000000000000000
R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000

Uninit was created at:
 kmsan_save_stack_with_flags mm/kmsan/kmsan.c:143 [inline]
 kmsan_internal_poison_shadow+0x66/0xd0 mm/kmsan/kmsan.c:126
 kmsan_slab_alloc+0x8a/0xe0 mm/kmsan/kmsan_hooks.c:80
 slab_alloc_node mm/slub.c:2907 [inline]
 slab_alloc mm/slub.c:2916 [inline]
 __kmalloc+0x2bb/0x4b0 mm/slub.c:3982
 kmalloc include/linux/slab.h:559 [inline]
 getdqbuf+0x56/0x150 fs/quota/quota_tree.c:52
 qtree_write_dquot+0xf2/0x870 fs/quota/quota_tree.c:378
 v2_write_dquot+0x1ad/0x280 fs/quota/quota_v2.c:333
 dquot_commit+0x4af/0x600 fs/quota/dquot.c:482
 ext4_write_dquot fs/ext4/super.c:5934 [inline]
 ext4_mark_dquot_dirty+0x4d8/0x6a0 fs/ext4/super.c:5985
 mark_dquot_dirty fs/quota/dquot.c:347 [inline]
 mark_all_dquot_dirty fs/quota/dquot.c:385 [inline]
 dquot_alloc_inode+0xc05/0x12b0 fs/quota/dquot.c:1755
 __ext4_new_inode+0x8204/0x9d70 fs/ext4/ialloc.c:1155
 ext4_tmpfile+0x41a/0x850 fs/ext4/namei.c:2686
 vfs_tmpfile+0x2a2/0x570 fs/namei.c:3283
 do_tmpfile fs/namei.c:3316 [inline]
 path_openat+0x4035/0x6a90 fs/namei.c:3359
 do_filp_open+0x2b8/0x710 fs/namei.c:3395
 do_sys_openat2+0xa88/0x1140 fs/open.c:1168
 do_sys_open fs/open.c:1184 [inline]
 __do_compat_sys_openat fs/open.c:1242 [inline]
 __se_compat_sys_openat+0x2a4/0x310 fs/open.c:1240
 __ia32_compat_sys_openat+0x56/0x70 fs/open.c:1240
 do_syscall_32_irqs_on arch/x86/entry/common.c:80 [inline]
 __do_fast_syscall_32+0x129/0x180 arch/x86/entry/common.c:139
 do_fast_syscall_32+0x6a/0xc0 arch/x86/entry/common.c:162
 do_SYSENTER_32+0x73/0x90 arch/x86/entry/common.c:205
 entry_SYSENTER_compat_after_hwframe+0x4d/0x5c

Fixes: 498c60153e ("quota: Implement quota format with 64-bit space and inode limits")
Link: https://lore.kernel.org/r/20200924183619.4176790-1-edumazet@google.com
Signed-off-by: Eric Dumazet <edumazet@google.com>
Cc: Jan Kara <jack@suse.com>
Signed-off-by: Jan Kara <jack@suse.cz>
2020-09-25 11:15:27 +02:00
Christoph Hellwig
80bdad3d7e quota: simplify the quotactl compat handling
Fold the misaligned u64 workarounds into the main quotactl flow instead
of implementing a separate compat syscall handler.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Acked-by: Jan Kara <jack@suse.cz>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2020-09-17 13:00:46 -04:00
Darrick J. Wong
ad47ff330b quota: widen timestamps for the fs_disk_quota structure
Soon, XFS will support quota grace period expiration timestamps beyond
the year 2038, widen the timestamp fields to handle the extra time bits.
Internally, XFS now stores unsigned 34-bit quantities, so the extra 8
bits here should work fine.  (Note that XFS is the only user of this
structure.)

Link: https://lore.kernel.org/r/20200909163413.GJ7955@magnolia
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jan Kara <jack@suse.cz>
2020-09-10 09:09:51 +02:00
Gustavo A. R. Silva
df561f6688 treewide: Use fallthrough pseudo-keyword
Replace the existing /* fall through */ comments and its variants with
the new pseudo-keyword macro fallthrough[1]. Also, remove unnecessary
fall-through markings when it is the case.

[1] https://www.kernel.org/doc/html/v5.7/process/deprecated.html?highlight=fallthrough#implicit-switch-case-fall-through

Signed-off-by: Gustavo A. R. Silva <gustavoars@kernel.org>
2020-08-23 17:36:59 -05:00
Linus Torvalds
09e70bb4d8 \n
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Merge tag 'for_v5.9-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/jack/linux-fs

Pull ext2, udf, reiserfs, quota cleanups and minor fixes from Jan Kara:
 "A few ext2 fixups and then several (mostly comment and documentation)
  cleanups in ext2, udf, reiserfs, and quota"

* tag 'for_v5.9-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/jack/linux-fs:
  reiserfs: delete duplicated words
  udf: osta_udf.h: delete a duplicated word
  reiserfs: reiserfs.h: delete a duplicated word
  ext2: ext2.h: fix duplicated word + typos
  udf: Replace HTTP links with HTTPS ones
  quota: Fixup http links in quota doc
  Replace HTTP links with HTTPS ones: DISKQUOTA
  ext2: initialize quota info in ext2_xattr_set()
  ext2: fix some incorrect comments in inode.c
  ext2: remove nocheck option
  ext2: fix missing percpu_counter_inc
  ext2: ext2_find_entry() return -ENOENT if no entry found
  ext2: propagate errors up to ext2_find_entry()'s callers
  ext2: fix improper assignment for e_value_offs
2020-08-06 19:28:26 -07:00
Alexander A. Klimov
1f1a5be80c Replace HTTP links with HTTPS ones: DISKQUOTA
Rationale:
Reduces attack surface on kernel devs opening the links for MITM
as HTTPS traffic is much harder to manipulate.

Deterministic algorithm:
For each file:
  If not .svg:
    For each line:
      If doesn't contain `\bxmlns\b`:
        For each link, `\bhttp://[^# \t\r\n]*(?:\w|/)`:
	  If neither `\bgnu\.org/license`, nor `\bmozilla\.org/MPL\b`:
            If both the HTTP and HTTPS versions
            return 200 OK and serve the same content:
              Replace HTTP with HTTPS.

Link: https://lore.kernel.org/r/20200708171905.15396-1-grandmaster@al2klimov.de
Signed-off-by: Alexander A. Klimov <grandmaster@al2klimov.de>
Signed-off-by: Jan Kara <jack@suse.cz>
2020-07-09 08:14:01 +02:00
Christoph Hellwig
3f1266f1f8 block: move block-related definitions out of fs.h
Move most of the block related definition out of fs.h into more suitable
headers.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2020-06-24 09:16:02 -06:00
Christoph Hellwig
32927393dc sysctl: pass kernel pointers to ->proc_handler
Instead of having all the sysctl handlers deal with user pointers, which
is rather hairy in terms of the BPF interaction, copy the input to and
from  userspace in common code.  This also means that the strings are
always NUL-terminated by the common code, making the API a little bit
safer.

As most handler just pass through the data to one of the common handlers
a lot of the changes are mechnical.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Acked-by: Andrey Ignatov <rdna@fb.com>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2020-04-27 02:07:40 -04:00
Linus Torvalds
0196be12aa \n
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Merge tag 'for_v5.6-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/jack/linux-fs

Pull UDF, quota, reiserfs, ext2 fixes and cleanups from Jan Kara:
 "A few assorted fixes and cleanups for udf, quota, reiserfs, and ext2"

* tag 'for_v5.6-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/jack/linux-fs:
  fs/reiserfs: remove unused macros
  fs/quota: remove unused macro
  udf: Clarify meaning of f_files in udf_statfs
  udf: Allow writing to 'Rewritable' partitions
  udf: Disallow R/W mode for disk with Metadata partition
  udf: Fix meaning of ENTITYID_FLAGS_* macros to be really bitwise-or flags
  udf: Fix free space reporting for metadata and virtual partitions
  udf: Update header files to UDF 2.60
  udf: Move OSTA Identifier Suffix macros from ecma_167.h to osta_udf.h
  udf: Fix spelling in EXT_NEXT_EXTENT_ALLOCDESCS
  ext2: Adjust indentation in ext2_fill_super
  quota: avoid time_t in v1_disk_dqblk definition
  reiserfs: Fix spurious unlock in reiserfs_fill_super() error handling
  reiserfs: Fix memory leak of journal device string
  ext2: set proper errno in error case of ext2_fill_super()
2020-01-30 15:37:41 -08:00
Alex Shi
ed21c58eef fs/quota: remove unused macro
__QUOTA_V2_PARANOIA  macro is never used. better to remove it.

Link: https://lore.kernel.org/r/1579602334-57039-1-git-send-email-alex.shi@linux.alibaba.com
Signed-off-by: Alex Shi <alex.shi@linux.alibaba.com>
Cc: Jan Kara <jack@suse.com>
Cc: linux-kernel@vger.kernel.org
Signed-off-by: Jan Kara <jack@suse.cz>
2020-01-21 17:22:00 +01:00
Eric Sandeen
04646aebd3 fs: avoid softlockups in s_inodes iterators
Anything that walks all inodes on sb->s_inodes list without rescheduling
risks softlockups.

Previous efforts were made in 2 functions, see:

c27d82f fs/drop_caches.c: avoid softlockups in drop_pagecache_sb()
ac05fbb inode: don't softlockup when evicting inodes

but there hasn't been an audit of all walkers, so do that now.  This
also consistently moves the cond_resched() calls to the bottom of each
loop in cases where it already exists.

One loop remains: remove_dquot_ref(), because I'm not quite sure how
to deal with that one w/o taking the i_lock.

Signed-off-by: Eric Sandeen <sandeen@redhat.com>
Reviewed-by: Jan Kara <jack@suse.cz>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2019-12-18 00:03:01 -05:00
Arnd Bergmann
1ead083ae1 quota: avoid time_t in v1_disk_dqblk definition
The time_t type is part of the user interface and not always the
same, with the move to 64-bit timestamps and the difference between
architectures.

Make the quota format definition independent of this type and use
a basic type of the same length. Make it unsigned in the process
to keep the v1 format working until year 2106 instead of 2038
on 32-bit architectures.

Hopefully, everybody has already moved to a newer format long
ago (v2 was introduced with linux-2.4), but it's hard to be sure.

Link: https://lore.kernel.org/r/20191213205221.3787308-6-arnd@arndb.de
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Jan Kara <jack@suse.cz>
2019-12-16 14:15:30 +01:00
Linus Torvalds
0aecba6173 Merge branch 'fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs
Pull vfs d_inode/d_flags memory ordering fixes from Al Viro:
 "Fallout from tree-wide audit for ->d_inode/->d_flags barriers use.
  Basically, the problem is that negative pinned dentries require
  careful treatment - unless ->d_lock is locked or parent is held at
  least shared, another thread can make them positive right under us.

  Most of the uses turned out to be safe - the main surprises as far as
  filesystems are concerned were

   - race in dget_parent() fastpath, that might end up with the caller
     observing the returned dentry _negative_, due to insufficient
     barriers. It is positive in memory, but we could end up seeing the
     wrong value of ->d_inode in CPU cache. Fixed.

   - manual checks that result of lookup_one_len_unlocked() is positive
     (and rejection of negatives). Again, insufficient barriers (we
     might end up with inconsistent observed values of ->d_inode and
     ->d_flags). Fixed by switching to a new primitive that does the
     checks itself and returns ERR_PTR(-ENOENT) instead of a negative
     dentry. That way we get rid of boilerplate converting negatives
     into ERR_PTR(-ENOENT) in the callers and have a single place to
     deal with the barrier-related mess - inside fs/namei.c rather than
     in every caller out there.

  The guts of pathname resolution *do* need to be careful - the race
  found by Ritesh is real, as well as several similar races.
  Fortunately, it turns out that we can take care of that with fairly
  local changes in there.

  The tree-wide audit had not been fun, and I hate the idea of repeating
  it. I think the right approach would be to annotate the places where
  we are _not_ guaranteed ->d_inode/->d_flags stability and have sparse
  catch regressions. But I'm still not sure what would be the least
  invasive way of doing that and it's clearly the next cycle fodder"

* 'fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs:
  fs/namei.c: fix missing barriers when checking positivity
  fix dget_parent() fastpath race
  new helper: lookup_positive_unlocked()
  fs/namei.c: pull positivity check into follow_managed()
2019-12-06 09:06:58 -08:00
Al Viro
6c2d4798a8 new helper: lookup_positive_unlocked()
Most of the callers of lookup_one_len_unlocked() treat negatives are
ERR_PTR(-ENOENT).  Provide a helper that would do just that.  Note
that a pinned positive dentry remains positive - it's ->d_inode is
stable, etc.; a pinned _negative_ dentry can become positive at any
point as long as you are not holding its parent at least shared.
So using lookup_one_len_unlocked() needs to be careful;
lookup_positive_unlocked() is safer and that's what the callers
end up open-coding anyway.

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2019-11-15 13:49:04 -05:00
Konstantin Khlebnikov
6fcbcec9cf fs/quota: handle overflows of sysctl fs.quota.* and report as unsigned long
Quota statistics counted as 64-bit per-cpu counter. Reading sums per-cpu
fractions as signed 64-bit int, filters negative values and then reports
lower half as signed 32-bit int.

Result may looks like:

fs.quota.allocated_dquots = 22327
fs.quota.cache_hits = -489852115
fs.quota.drops = -487288718
fs.quota.free_dquots = 22083
fs.quota.lookups = -486883485
fs.quota.reads = 22327
fs.quota.syncs = 335064
fs.quota.writes = 3088689

Values bigger than 2^31-1 reported as negative.

All counters except "allocated_dquots" and "free_dquots" are monotonic,
thus they should be reported as is without filtering negative values.

Kernel doesn't have generic helper for 64-bit sysctl yet,
let's use at least unsigned long.

Link: https://lore.kernel.org/r/157337934693.2078.9842146413181153727.stgit@buzz
Signed-off-by: Konstantin Khlebnikov <khlebnikov@yandex-team.ru>
Signed-off-by: Jan Kara <jack@suse.cz>
2019-11-11 11:06:27 +01:00
Jan Kara
dae82c7fd0 Pull series refactoring quota enabling and disabling code. 2019-11-06 10:52:10 +01:00
Jan Kara
a0828b6ccb quota: Handle quotas without quota inodes in dquot_get_state()
Make dquot_get_state() gracefully handle a situation when there are no
quota files present even though quotas are enabled.

Signed-off-by: Jan Kara <jack@suse.cz>
2019-11-04 11:21:40 +01:00
Jan Kara
2ec1f3011f quota: Make dquot_disable() work without quota inodes
Quota on and quota off are protected by s_umount semaphore held in
exclusive mode since commit 7d6cd73d33 "quota: Hold s_umount in
exclusive mode when enabling / disabling quotas". This makes it
impossible for dquot_disable() to race with other enabling or disabling
of quotas. Simplify the cleanup done by dquot_disable() based on this
fact and also remove some stale comments. As a bonus this cleanup makes
dquot_disable() properly handle a case when there are no quota inodes.

Signed-off-by: Jan Kara <jack@suse.cz>
2019-11-04 11:21:35 +01:00
Jan Kara
069a916636 quota: Drop dquot_enable()
Now dquot_enable() has only two internal callers and both of them just
need to update quota flags and don't need most of checks. Just drop
dquot_enable() and fold necessary functionality into the two calling
places.

Signed-off-by: Jan Kara <jack@suse.cz>
2019-11-04 09:58:06 +01:00
Jan Kara
dc19432ae1 quota: Rename vfs_load_quota_inode() to dquot_load_quota_inode()
Rename vfs_load_quota_inode() to dquot_load_quota_inode() to be
consistent with naming of other functions used for enabling quota
accounting from filesystems. Also export the function and add some
sanity checks to assure filesystems are calling the function properly.

Signed-off-by: Jan Kara <jack@suse.cz>
2019-11-04 09:58:05 +01:00
Jan Kara
ae45f07d47 quota: Simplify dquot_resume()
We already have quota inode loaded when resuming quotas. Use
vfs_load_quota() to avoid some pointless churn with the quota inode.

Signed-off-by: Jan Kara <jack@suse.cz>
2019-11-04 09:58:05 +01:00
Jan Kara
c7d3d28360 quota: Factor out setup of quota inode
Factor out setting up of quota inode and eventual error cleanup from
vfs_load_quota_inode(). This will simplify situation for filesystems
that don't have any quota inodes.

Signed-off-by: Jan Kara <jack@suse.cz>
2019-11-04 09:58:01 +01:00
Dmitry Monakhov
df4bb5d128 quota: Check that quota is not dirty before release
There is a race window where quota was redirted once we drop dq_list_lock inside dqput(),
but before we grab dquot->dq_lock inside dquot_release()

TASK1                                                       TASK2 (chowner)
->dqput()
  we_slept:
    spin_lock(&dq_list_lock)
    if (dquot_dirty(dquot)) {
          spin_unlock(&dq_list_lock);
          dquot->dq_sb->dq_op->write_dquot(dquot);
          goto we_slept
    if (test_bit(DQ_ACTIVE_B, &dquot->dq_flags)) {
          spin_unlock(&dq_list_lock);
          dquot->dq_sb->dq_op->release_dquot(dquot);
                                                            dqget()
							    mark_dquot_dirty()
							    dqput()
          goto we_slept;
        }
So dquot dirty quota will be released by TASK1, but on next we_sleept loop
we detect this and call ->write_dquot() for it.
XFSTEST: 440a80d4cb

Link: https://lore.kernel.org/r/20191031103920.3919-2-dmonakhov@openvz.org
CC: stable@vger.kernel.org
Signed-off-by: Dmitry Monakhov <dmtrmonakhov@yandex-team.ru>
Signed-off-by: Jan Kara <jack@suse.cz>
2019-10-31 19:07:42 +01:00
Dmitry Monakhov
6ff33d99fc quota: fix livelock in dquot_writeback_dquots
Write only quotas which are dirty at entry.

XFSTEST: b10ad23566

Link: https://lore.kernel.org/r/20191031103920.3919-1-dmonakhov@openvz.org
CC: stable@vger.kernel.org
Signed-off-by: Konstantin Khlebnikov <khlebnikov@yandex-team.ru>
Signed-off-by: Dmitry Monakhov <dmtrmonakhov@yandex-team.ru>
Signed-off-by: Jan Kara <jack@suse.cz>
2019-10-31 19:07:11 +01:00
Chengguang Xu
d02601c398 quota: minor code cleanup for v1_format_ops
It's not a functinal change, it's just for keeping
consistent coding style.

Link: https://lore.kernel.org/r/20191010130924.17697-1-cgxu519@mykernel.net
Signed-off-by: Chengguang Xu <cgxu519@mykernel.net>
Signed-off-by: Jan Kara <jack@suse.cz>
2019-10-17 10:30:28 +02:00
Chengguang Xu
a6810312b8 quota: check quota type in early stage
Check quota type in early stage so we can avoid many
unncessary operations when the type is wrong.

Link: https://lore.kernel.org/r/20191008145059.21402-1-cgxu519@mykernel.net
Signed-off-by: Chengguang Xu <cgxu519@mykernel.net>
Signed-off-by: Jan Kara <jack@suse.cz>
2019-10-08 17:26:18 +02:00
Chengguang Xu
24fc755f56 quota: code cleanup for hash bits calculation
Code cleanup for hash bits calculation by
calling ilog2().

Link: https://lore.kernel.org/r/20190923135223.27674-1-cgxu519@zoho.com.cn
Signed-off-by: Chengguang Xu <cgxu519@zoho.com.cn>
Signed-off-by: Jan Kara <jack@suse.cz>
2019-10-04 10:11:46 +02:00
Chengguang Xu
05848db208 quota: avoid increasing DQST_LOOKUPS when iterating over dirty/inuse list
It is meaningless to increase DQST_LOOKUPS number while iterating
over dirty/inuse list, so just avoid it.

Link: https://lore.kernel.org/r/20190926083408.4269-1-cgxu519@zoho.com.cn
Signed-off-by: Chengguang Xu <cgxu519@zoho.com.cn>
Signed-off-by: Jan Kara <jack@suse.cz>
2019-10-04 10:07:38 +02:00
Chengguang Xu
4b8e1106dd quota: fix condition for resetting time limit in do_set_dqblk()
We reset time limit when current usage is smaller
or equal to soft limit in other place, so follow
this rule in do_set_dqblk().

Signed-off-by: Chengguang Xu <cgxu519@zoho.com.cn>
Link: https://lore.kernel.org/r/20190724053216.19392-1-cgxu519@zoho.com.cn
Signed-off-by: Jan Kara <jack@suse.cz>
2019-07-31 12:04:42 +02:00
Linus Torvalds
682f7c5c46 \n
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Merge tag 'for_v5.3-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/jack/linux-fs

Pull ext2, udf and quota updates from Jan Kara:

 - some ext2 fixes and cleanups

 - a fix of udf bug when extending files

 - a fix of quota Q_XGETQSTAT[V] handling

* tag 'for_v5.3-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/jack/linux-fs:
  udf: Fix incorrect final NOT_ALLOCATED (hole) extent length
  ext2: Use kmemdup rather than duplicating its implementation
  quota: honor quota type in Q_XGETQSTAT[V] calls
  ext2: Always brelse bh on failure in ext2_iget()
  ext2: add missing brelse() in ext2_iget()
  ext2: Fix a typo in ext2_getattr argument
  ext2: fix a typo in comment
  ext2: add missing brelse() in ext2_new_inode()
  ext2: optimize ext2_xattr_get()
  ext2: introduce new helper for xattr entry comparison
  ext2: merge xattr next entry check to ext2_xattr_entry_valid()
  ext2: code cleanup for ext2_preread_inode()
  ext2: code cleanup by using test_opt() and clear_opt()
  doc: ext2: update description of quota options for ext2
  ext2: Strengthen xattr block checks
  ext2: Merge loops in ext2_xattr_set()
  ext2: introduce helper for xattr entry validation
  ext2: introduce helper for xattr header validation
  quota: add dqi_dirty_list description to comment of Dquot List Management
2019-07-10 20:27:07 -07:00
Eric Sandeen
555b2c3da1 quota: honor quota type in Q_XGETQSTAT[V] calls
The code in quota_getstate and quota_getstatev is strange; it
says the returned fs_quota_stat[v] structure has room for only
one type of time limits, so fills it in with the first enabled
quota, even though every quotactl command must have a type sent
in by the user.

Instead of just picking the first enabled quota, fill in the
reply with the timers for the quota type that was actually
requested.

Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Eric Sandeen <sandeen@redhat.com>
Signed-off-by: Jan Kara <jack@suse.cz>
2019-06-25 17:51:35 +02:00
yangerkun
c6d9c35d16 quota: fix a problem about transfer quota
Run below script as root, dquot_add_space will return -EDQUOT since
__dquot_transfer call dquot_add_space with flags=0, and dquot_add_space
think it's a preallocation. Fix it by set flags as DQUOT_SPACE_WARN.

mkfs.ext4 -O quota,project /dev/vdb
mount -o prjquota /dev/vdb /mnt
setquota -P 23 1 1 0 0 /dev/vdb
dd if=/dev/zero of=/mnt/test-file bs=4K count=1
chattr -p 23 test-file

Fixes: 7b9ca4c61b ("quota: Reduce contention on dq_data_lock")
Signed-off-by: yangerkun <yangerkun@huawei.com>
Signed-off-by: Jan Kara <jack@suse.cz>
2019-06-19 15:25:41 +02:00
Thomas Gleixner
ec8f24b7fa treewide: Add SPDX license identifier - Makefile/Kconfig
Add SPDX license identifiers to all Make/Kconfig files which:

 - Have no license information of any form

These files fall under the project license, GPL v2 only. The resulting SPDX
license identifier is:

  GPL-2.0-only

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-05-21 10:50:46 +02:00
Thomas Gleixner
09c434b8a0 treewide: Add SPDX license identifier for more missed files
Add SPDX license identifiers to all files which:

 - Have no license information of any form

 - Have MODULE_LICENCE("GPL*") inside which was used in the initial
   scan/conversion to ignore the file

These files fall under the project license, GPL v2 only. The resulting SPDX
license identifier is:

  GPL-2.0-only

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-05-21 10:50:45 +02:00
Chengguang Xu
f44840ad1f quota: add dqi_dirty_list description to comment of Dquot List Management
Actually there are four lists for dquot management, so add
the description of dqui_dirty_list to comment.

Signed-off-by: Chengguang Xu <cgxu519@gmail.com>
Signed-off-by: Jan Kara <jack@suse.cz>
2019-05-20 10:50:48 +02:00
Chengguang Xu
632a9f3acd quota: check time limit when back out space/inode change
When we fail from allocating inode/space, we back out
the change we already did. In a special case which has
exceeded soft limit by the change, we should also check
time limit and reset it properly.

Signed-off-by: Chengguang Xu <cgxu519@gmx.com>
Signed-off-by: Jan Kara <jack@suse.cz>
2019-04-30 18:05:55 +02:00
Jiang Biao
78bc3334a6 fs/quota: erase unused but set variable warning
Local variable *reserved* of remove_dquot_ref() is only used if
define CONFIG_QUOTA_DEBUG, but not ebraced in CONFIG_QUOTA_DEBUG
macro, which leads to unused-but-set-variable warning when compiling.

This patch ebrace it into CONFIG_QUOTA_DEBUG macro like what is done
in add_dquot_ref().

Signed-off-by: Jiang Biao <benbjiang@tencent.com>
Signed-off-by: Jan Kara <jack@suse.cz>
2019-04-25 17:04:43 +02:00
Chengguang Xu
3ef177ec9d quota: fix wrong indentation
We need to check return code only when calling ->read_dqblk(),
so fix it properly.

Signed-off-by: Chengguang Xu <cgxu519@gmx.com>
Signed-off-by: Jan Kara <jack@suse.cz>
2019-04-25 11:59:35 +02:00
Sascha Hauer
27942ef503 quota: remove trailing whitespaces
This removes all trailing whitespaces in fs/quota/.

Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>
Signed-off-by: Jan Kara <jack@suse.cz>
2019-03-26 11:21:37 +01:00
Chengguang Xu
df15a2a59d quota: code cleanup for __dquot_alloc_space()
Replace (flags & DQUOT_SPACE_RESERVE) with
variable reserve.

Signed-off-by: Chengguang Xu <cgxu519@gmx.com>
Signed-off-by: Jan Kara <jack@suse.cz>
2019-03-26 11:21:23 +01:00
Javier Barrio
41c4f85cda quota: Lock s_umount in exclusive mode for Q_XQUOTA{ON,OFF} quotactls.
Commit 1fa5efe362 (ext4: Use generic helpers for quotaon
and quotaoff) made possible to call quotactl(Q_XQUOTAON/OFF) on ext4 filesystems
with sysfile quota support. This leads to calling dquot_enable/disable without s_umount
held in excl. mode, because quotactl_cmd_onoff checks only for Q_QUOTAON/OFF.

The following WARN_ON_ONCE triggers (in this case for dquot_enable, ext4, latest Linus' tree):

[  117.807056] EXT4-fs (dm-0): mounted filesystem with ordered data mode. Opts: quota,prjquota

[...]

[  155.036847] WARNING: CPU: 0 PID: 2343 at fs/quota/dquot.c:2469 dquot_enable+0x34/0xb9
[  155.036851] Modules linked in: quota_v2 quota_tree ipv6 af_packet joydev mousedev psmouse serio_raw pcspkr i2c_piix4 intel_agp intel_gtt e1000 ttm drm_kms_helper drm agpgart fb_sys_fops syscopyarea sysfillrect sysimgblt i2c_core input_leds kvm_intel kvm irqbypass qemu_fw_cfg floppy evdev parport_pc parport button crc32c_generic dm_mod ata_generic pata_acpi ata_piix libata loop ext4 crc16 mbcache jbd2 usb_storage usbcore sd_mod scsi_mod
[  155.036901] CPU: 0 PID: 2343 Comm: qctl Not tainted 4.20.0-rc6-00025-gf5d582777bcb #9
[  155.036903] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.10.2-1ubuntu1 04/01/2014
[  155.036911] RIP: 0010:dquot_enable+0x34/0xb9
[  155.036915] Code: 41 56 41 55 41 54 55 53 4c 8b 6f 28 74 02 0f 0b 4d 8d 7d 70 49 89 fc 89 cb 41 89 d6 89 f5 4c 89 ff e8 23 09 ea ff 85 c0 74 0a <0f> 0b 4c 89 ff e8 8b 09 ea ff 85 db 74 6a 41 8b b5 f8 00 00 00 0f
[  155.036918] RSP: 0018:ffffb09b00493e08 EFLAGS: 00010202
[  155.036922] RAX: 0000000000000001 RBX: 0000000000000008 RCX: 0000000000000008
[  155.036924] RDX: 0000000000000001 RSI: 0000000000000002 RDI: ffff9781b67cd870
[  155.036926] RBP: 0000000000000002 R08: 0000000000000000 R09: 61c8864680b583eb
[  155.036929] R10: ffffb09b00493e48 R11: ffffffffff7ce7d4 R12: ffff9781b7ee8d78
[  155.036932] R13: ffff9781b67cd800 R14: 0000000000000004 R15: ffff9781b67cd870
[  155.036936] FS:  00007fd813250b88(0000) GS:ffff9781ba000000(0000) knlGS:0000000000000000
[  155.036939] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[  155.036942] CR2: 00007fd812ff61d6 CR3: 000000007c882000 CR4: 00000000000006b0
[  155.036951] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
[  155.036953] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
[  155.036955] Call Trace:
[  155.037004]  dquot_quota_enable+0x8b/0xd0
[  155.037011]  kernel_quotactl+0x628/0x74e
[  155.037027]  ? do_mprotect_pkey+0x2a6/0x2cd
[  155.037034]  __x64_sys_quotactl+0x1a/0x1d
[  155.037041]  do_syscall_64+0x55/0xe4
[  155.037078]  entry_SYSCALL_64_after_hwframe+0x44/0xa9
[  155.037105] RIP: 0033:0x7fd812fe1198
[  155.037109] Code: 02 77 0d 48 89 c1 48 c1 e9 3f 75 04 48 8b 04 24 48 83 c4 50 5b c3 48 83 ec 08 49 89 ca 48 63 d2 48 63 ff b8 b3 00 00 00 0f 05 <48> 89 c7 e8 c1 eb ff ff 5a c3 48 63 ff b8 bb 00 00 00 0f 05 48 89
[  155.037112] RSP: 002b:00007ffe8cd7b050 EFLAGS: 00000206 ORIG_RAX: 00000000000000b3
[  155.037116] RAX: ffffffffffffffda RBX: 00007ffe8cd7b148 RCX: 00007fd812fe1198
[  155.037119] RDX: 0000000000000000 RSI: 00007ffe8cd7cea9 RDI: 0000000000580102
[  155.037121] RBP: 00007ffe8cd7b0f0 R08: 000055fc8eba8a9d R09: 0000000000000000
[  155.037124] R10: 00007ffe8cd7b074 R11: 0000000000000206 R12: 00007ffe8cd7b168
[  155.037126] R13: 000055fc8eba8897 R14: 0000000000000000 R15: 0000000000000000
[  155.037131] ---[ end trace 210f864257175c51 ]---

and then the syscall proceeds without s_umount locking.

This patch locks the superblock ->s_umount sem. in exclusive mode for all Q_XQUOTAON/OFF
quotactls too in addition to Q_QUOTAON/OFF.

AFAICT, other than ext4, only xfs and ocfs2 are affected by this change.
The VFS will now call in xfs_quota_* functions with s_umount held, which wasn't the case
before. This looks good to me but I can not say for sure. Ext4 and ocfs2 where already
beeing called with s_umount exclusive via quota_quotaon/off which is basically the same.

Signed-off-by: Javier Barrio <javier.barrio.mart@gmail.com>
Signed-off-by: Jan Kara <jack@suse.cz>
2018-12-18 18:29:15 +01:00