1104 Commits

Author SHA1 Message Date
Baokun Li
d04a3ff04c ext4: only update i_reserved_data_blocks on successful block allocation
commit de25d6e9610a8b30cce9bbb19b50615d02ebca02 upstream.

In our fault injection test, we create an ext4 file, migrate it to
non-extent based file, then punch a hole and finally trigger a WARN_ON
in the ext4_da_update_reserve_space():

EXT4-fs warning (device sda): ext4_da_update_reserve_space:369:
ino 14, used 11 with only 10 reserved data blocks

When writing back a non-extent based file, if we enable delalloc, the
number of reserved blocks will be subtracted from the number of blocks
mapped by ext4_ind_map_blocks(), and the extent status tree will be
updated. We update the extent status tree by first removing the old
extent_status and then inserting the new extent_status. If the block range
we remove happens to be in an extent, then we need to allocate another
extent_status with ext4_es_alloc_extent().

       use old    to remove   to add new
    |----------|------------|------------|
              old extent_status

The problem is that the allocation of a new extent_status failed due to a
fault injection, and __es_shrink() did not get free memory, resulting in
a return of -ENOMEM. Then do_writepages() retries after receiving -ENOMEM,
we map to the same extent again, and the number of reserved blocks is again
subtracted from the number of blocks in that extent. Since the blocks in
the same extent are subtracted twice, we end up triggering WARN_ON at
ext4_da_update_reserve_space() because used > ei->i_reserved_data_blocks.

For non-extent based file, we update the number of reserved blocks after
ext4_ind_map_blocks() is executed, which causes a problem that when we call
ext4_ind_map_blocks() to create a block, it doesn't always create a block,
but we always reduce the number of reserved blocks. So we move the logic
for updating reserved blocks to ext4_ind_map_blocks() to ensure that the
number of reserved blocks is updated only after we do succeed in allocating
some new blocks.

Fixes: 5f634d064c70 ("ext4: Fix quota accounting error with fallocate")
Cc: stable@kernel.org
Signed-off-by: Baokun Li <libaokun1@huawei.com>
Reviewed-by: Jan Kara <jack@suse.cz>
Link: https://lore.kernel.org/r/20230424033846.4732-2-libaokun1@huawei.com
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-07-23 13:47:49 +02:00
Theodore Ts'o
a8c3024c3e ext4: disallow ea_inodes with extended attributes
commit 2bc7e7c1a3bc9bd0cbf0f71006f6fe7ef24a00c2 upstream.

An ea_inode stores the value of an extended attribute; it can not have
extended attributes itself, or this will cause recursive nightmares.
Add a check in ext4_iget() to make sure this is the case.

Cc: stable@kernel.org
Reported-by: syzbot+e44749b6ba4d0434cd47@syzkaller.appspotmail.com
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Link: https://lore.kernel.org/r/20230524034951.779531-4-tytso@mit.edu
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-06-09 10:32:33 +02:00
Theodore Ts'o
bdbfbb7d50 ext4: add EA_INODE checking to ext4_iget()
commit b3e6bcb94590dea45396b9481e47b809b1be4afa upstream.

Add a new flag, EXT4_IGET_EA_INODE which indicates whether the inode
is expected to have the EA_INODE flag or not.  If the flag is not
set/clear as expected, then fail the iget() operation and mark the
file system as corrupted.

This commit also makes the ext4_iget() always perform the
is_bad_inode() check even when the inode is already inode cache.  This
allows us to remove the is_bad_inode() check from the callers of
ext4_iget() in the ea_inode code.

Reported-by: syzbot+cbb68193bdb95af4340a@syzkaller.appspotmail.com
Reported-by: syzbot+62120febbd1ee3c3c860@syzkaller.appspotmail.com
Reported-by: syzbot+edce54daffee36421b4c@syzkaller.appspotmail.com
Cc: stable@kernel.org
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Link: https://lore.kernel.org/r/20230524034951.779531-2-tytso@mit.edu
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-06-09 10:32:32 +02:00
Baokun Li
5f7d66e5e5 ext4: check iomap type only if ext4_iomap_begin() does not fail
commit fa83c34e3e56b3c672af38059e066242655271b1 upstream.

When ext4_iomap_overwrite_begin() calls ext4_iomap_begin() map blocks may
fail for some reason (e.g. memory allocation failure, bare disk write), and
later because "iomap->type ! = IOMAP_MAPPED" triggers WARN_ON(). When ext4
iomap_begin() returns an error, it is normal that the type of iomap->type
may not match the expectation. Therefore, we only determine if iomap->type
is as expected when ext4_iomap_begin() is executed successfully.

Cc: stable@kernel.org
Reported-by: syzbot+08106c4b7d60702dbc14@syzkaller.appspotmail.com
Link: https://lore.kernel.org/all/00000000000015760b05f9b4eee9@google.com
Signed-off-by: Baokun Li <libaokun1@huawei.com>
Reviewed-by: Jan Kara <jack@suse.cz>
Link: https://lore.kernel.org/r/20230505132429.714648-1-libaokun1@huawei.com
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-05-17 11:50:29 +02:00
Zhihao Cheng
18eb23891a ext4: fix i_disksize exceeding i_size problem in paritally written case
[ Upstream commit 1dedde690303c05ef732b7c5c8356fdf60a4ade3 ]

It is possible for i_disksize can exceed i_size, triggering a warning.

generic_perform_write
 copied = iov_iter_copy_from_user_atomic(len) // copied < len
 ext4_da_write_end
 | ext4_update_i_disksize
 |  new_i_size = pos + copied;
 |  WRITE_ONCE(EXT4_I(inode)->i_disksize, newsize) // update i_disksize
 | generic_write_end
 |  copied = block_write_end(copied, len) // copied = 0
 |   if (unlikely(copied < len))
 |    if (!PageUptodate(page))
 |     copied = 0;
 |  if (pos + copied > inode->i_size) // return false
 if (unlikely(copied == 0))
  goto again;
 if (unlikely(iov_iter_fault_in_readable(i, bytes))) {
  status = -EFAULT;
  break;
 }

We get i_disksize greater than i_size here, which could trigger WARNING
check 'i_size_read(inode) < EXT4_I(inode)->i_disksize' while doing dio:

ext4_dio_write_iter
 iomap_dio_rw
  __iomap_dio_rw // return err, length is not aligned to 512
 ext4_handle_inode_extension
  WARN_ON_ONCE(i_size_read(inode) < EXT4_I(inode)->i_disksize) // Oops

 WARNING: CPU: 2 PID: 2609 at fs/ext4/file.c:319
 CPU: 2 PID: 2609 Comm: aa Not tainted 6.3.0-rc2
 RIP: 0010:ext4_file_write_iter+0xbc7
 Call Trace:
  vfs_write+0x3b1
  ksys_write+0x77
  do_syscall_64+0x39

Fix it by updating 'copied' value before updating i_disksize just like
ext4_write_inline_data_end() does.

A reproducer can be found in the buganizer link below.

Link: https://bugzilla.kernel.org/show_bug.cgi?id=217209
Fixes: 64769240bd07 ("ext4: Add delayed allocation support in data=writeback mode")
Signed-off-by: Zhihao Cheng <chengzhihao1@huawei.com>
Reviewed-by: Jan Kara <jack@suse.cz>
Link: https://lore.kernel.org/r/20230321013721.89818-1-chengzhihao1@huawei.com
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2023-05-11 23:00:37 +09:00
Harshad Shirwadkar
ac44e1275d ext4: use ext4_journal_start/stop for fast commit transactions
commit 2729cfdcfa1cc49bef5a90d046fa4a187fdfcc69 upstream.

This patch drops all calls to ext4_fc_start_update() and
ext4_fc_stop_update(). To ensure that there are no ongoing journal
updates during fast commit, we also make jbd2_fc_begin_commit() lock
journal for updates. This way we don't have to maintain two different
transaction start stop APIs for fast commit and full commit. This
patch doesn't remove the functions altogether since in future we want
to have inode level locking for fast commits.

Signed-off-by: Harshad Shirwadkar <harshadshirwadkar@gmail.com>
Link: https://lore.kernel.org/r/20211223202140.2061101-2-harshads@google.com
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Signed-off-by: Jan Kara <jack@suse.cz>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-05-11 23:00:16 +09:00
Baokun Li
088da6b805 ext4: fail ext4_iget if special inode unallocated
[ Upstream commit 5cd740287ae5e3f9d1c46f5bfe8778972fd6d3fe ]

In ext4_fill_super(), EXT4_ORPHAN_FS flag is cleared after
ext4_orphan_cleanup() is executed. Therefore, when __ext4_iget() is
called to get an inode whose i_nlink is 0 when the flag exists, no error
is returned. If the inode is a special inode, a null pointer dereference
may occur. If the value of i_nlink is 0 for any inodes (except boot loader
inodes) got by using the EXT4_IGET_SPECIAL flag, the current file system
is corrupted. Therefore, make the ext4_iget() function return an error if
it gets such an abnormal special inode.

Link: https://bugzilla.kernel.org/show_bug.cgi?id=199179
Link: https://bugzilla.kernel.org/show_bug.cgi?id=216541
Link: https://bugzilla.kernel.org/show_bug.cgi?id=216539
Reported-by: Luís Henriques <lhenriques@suse.de>
Suggested-by: Theodore Ts'o <tytso@mit.edu>
Signed-off-by: Baokun Li <libaokun1@huawei.com>
Reviewed-by: Jan Kara <jack@suse.cz>
Link: https://lore.kernel.org/r/20230107032126.4165860-2-libaokun1@huawei.com
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2023-03-22 13:31:30 +01:00
Ye Bin
d16576142f ext4: move where set the MAY_INLINE_DATA flag is set
commit 1dcdce5919115a471bf4921a57f20050c545a236 upstream.

The only caller of ext4_find_inline_data_nolock() that needs setting of
EXT4_STATE_MAY_INLINE_DATA flag is ext4_iget_extra_inode().  In
ext4_write_inline_data_end() we just need to update inode->i_inline_off.
Since we are going to add one more caller that does not need to set
EXT4_STATE_MAY_INLINE_DATA, just move setting of EXT4_STATE_MAY_INLINE_DATA
out to ext4_iget_extra_inode().

Signed-off-by: Ye Bin <yebin10@huawei.com>
Cc: stable@kernel.org
Reviewed-by: Jan Kara <jack@suse.cz>
Link: https://lore.kernel.org/r/20230307015253.2232062-2-yebin@huaweicloud.com
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-03-17 08:48:48 +01:00
Eric Biggers
37914e029b ext4: use ext4_debug() instead of jbd_debug()
From: Jan Kara <jack@suse.cz>

commit 4978c659e7b5c1926cdb4b556e4ca1fd2de8ad42 upstream.

We use jbd_debug() in some places in ext4. It seems a bit strange to use
jbd2 debugging output function for ext4 code. Also these days
ext4_debug() uses dynamic printk so each debug message can be enabled /
disabled on its own so the time when it made some sense to have these
combined (to allow easier common selecting of messages to report) has
passed. Just convert all jbd_debug() uses in ext4 to ext4_debug().

Signed-off-by: Jan Kara <jack@suse.cz>
Reviewed-by: Lukas Czerner <lczerner@redhat.com>
Link: https://lore.kernel.org/r/20220608112355.4397-1-jack@suse.cz
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Signed-off-by: Eric Biggers <ebiggers@google.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-01-12 11:59:04 +01:00
Jan Kara
e995ff918e ext4: avoid unaccounted block allocation when expanding inode
commit 8994d11395f8165b3deca1971946f549f0822630 upstream.

When expanding inode space in ext4_expand_extra_isize_ea() we may need
to allocate external xattr block. If quota is not initialized for the
inode, the block allocation will not be accounted into quota usage. Make
sure the quota is initialized before we try to expand inode space.

Reported-by: Pengfei Xu <pengfei.xu@intel.com>
Link: https://lore.kernel.org/all/Y5BT+k6xWqthZc1P@xpf.sh.intel.com
Signed-off-by: Jan Kara <jack@suse.cz>
Cc: stable@kernel.org
Link: https://lore.kernel.org/r/20221207115937.26601-2-jack@suse.cz
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-01-12 11:59:03 +01:00
Ye Bin
6380a93b57 ext4: fix kernel BUG in 'ext4_write_inline_data_end()'
commit 5c099c4fdc438014d5893629e70a8ba934433ee8 upstream.

Syzbot report follow issue:
------------[ cut here ]------------
kernel BUG at fs/ext4/inline.c:227!
invalid opcode: 0000 [#1] PREEMPT SMP KASAN
CPU: 1 PID: 3629 Comm: syz-executor212 Not tainted 6.1.0-rc5-syzkaller-00018-g59d0d52c30d4 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/26/2022
RIP: 0010:ext4_write_inline_data+0x344/0x3e0 fs/ext4/inline.c:227
RSP: 0018:ffffc90003b3f368 EFLAGS: 00010293
RAX: 0000000000000000 RBX: ffff8880704e16c0 RCX: 0000000000000000
RDX: ffff888021763a80 RSI: ffffffff821e31a4 RDI: 0000000000000006
RBP: 000000000006818e R08: 0000000000000006 R09: 0000000000068199
R10: 0000000000000079 R11: 0000000000000000 R12: 000000000000000b
R13: 0000000000068199 R14: ffffc90003b3f408 R15: ffff8880704e1c82
FS:  000055555723e3c0(0000) GS:ffff8880b9b00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007fffe8ac9080 CR3: 0000000079f81000 CR4: 0000000000350ee0
Call Trace:
 <TASK>
 ext4_write_inline_data_end+0x2a3/0x12f0 fs/ext4/inline.c:768
 ext4_write_end+0x242/0xdd0 fs/ext4/inode.c:1313
 ext4_da_write_end+0x3ed/0xa30 fs/ext4/inode.c:3063
 generic_perform_write+0x316/0x570 mm/filemap.c:3764
 ext4_buffered_write_iter+0x15b/0x460 fs/ext4/file.c:285
 ext4_file_write_iter+0x8bc/0x16e0 fs/ext4/file.c:700
 call_write_iter include/linux/fs.h:2191 [inline]
 do_iter_readv_writev+0x20b/0x3b0 fs/read_write.c:735
 do_iter_write+0x182/0x700 fs/read_write.c:861
 vfs_iter_write+0x74/0xa0 fs/read_write.c:902
 iter_file_splice_write+0x745/0xc90 fs/splice.c:686
 do_splice_from fs/splice.c:764 [inline]
 direct_splice_actor+0x114/0x180 fs/splice.c:931
 splice_direct_to_actor+0x335/0x8a0 fs/splice.c:886
 do_splice_direct+0x1ab/0x280 fs/splice.c:974
 do_sendfile+0xb19/0x1270 fs/read_write.c:1255
 __do_sys_sendfile64 fs/read_write.c:1323 [inline]
 __se_sys_sendfile64 fs/read_write.c:1309 [inline]
 __x64_sys_sendfile64+0x1d0/0x210 fs/read_write.c:1309
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x39/0xb0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x63/0xcd
---[ end trace 0000000000000000 ]---

Above issue may happens as follows:
ext4_da_write_begin
  ext4_da_write_inline_data_begin
    ext4_da_convert_inline_data_to_extent
      ext4_clear_inode_state(inode, EXT4_STATE_MAY_INLINE_DATA);
ext4_da_write_end

ext4_run_li_request
  ext4_mb_prefetch
    ext4_read_block_bitmap_nowait
      ext4_validate_block_bitmap
        ext4_mark_group_bitmap_corrupted(sb, block_group, EXT4_GROUP_INFO_BBITMAP_CORRUPT)
	 percpu_counter_sub(&sbi->s_freeclusters_counter,grp->bb_free);
	  -> sbi->s_freeclusters_counter become zero
ext4_da_write_begin
  if (ext4_nonda_switch(inode->i_sb)) -> As freeclusters_counter is zero will return true
    *fsdata = (void *)FALL_BACK_TO_NONDELALLOC;
    ext4_write_begin
ext4_da_write_end
  if (write_mode == FALL_BACK_TO_NONDELALLOC)
    ext4_write_end
      if (inline_data)
        ext4_write_inline_data_end
	  ext4_write_inline_data
	    BUG_ON(pos + len > EXT4_I(inode)->i_inline_size);
           -> As inode is already convert to extent, so 'pos + len' > inline_size
	   -> then trigger BUG.

To solve this issue, instead of checking ext4_has_inline_data() which
is only cleared after data has been written back, check the
EXT4_STATE_MAY_INLINE_DATA flag in ext4_write_end().

Fixes: f19d5870cbf7 ("ext4: add normal write support for inline data")
Reported-by: syzbot+4faa160fa96bfba639f8@syzkaller.appspotmail.com
Reported-by: Jun Nie <jun.nie@linaro.org>
Signed-off-by: Ye Bin <yebin10@huawei.com>
Link: https://lore.kernel.org/r/20221206144134.1919987-1-yebin@huaweicloud.com
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Cc: stable@kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-01-12 11:59:02 +01:00
Zhang Yi
91009e361e ext4: check and assert if marking an no_delete evicting inode dirty
commit 318cdc822c63b6e2befcfdc2088378ae6fa18def upstream.

In ext4_evict_inode(), if we evicting an inode in the 'no_delete' path,
it cannot be raced by another mark_inode_dirty(). If it happens,
someone else may accidentally dirty it without holding inode refcount
and probably cause use-after-free issues in the writeback procedure.
It's indiscoverable and hard to debug, so add an WARN_ON_ONCE() to
check and detect this issue in advance.

Suggested-by: Jan Kara <jack@suse.cz>
Signed-off-by: Zhang Yi <yi.zhang@huawei.com>
Reviewed-by: Jan Kara <jack@suse.cz>
Link: https://lore.kernel.org/r/20220629112647.4141034-2-yi.zhang@huawei.com
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Cc: stable@kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-01-12 11:59:01 +01:00
Baokun Li
f7e6b5548f ext4: add EXT4_IGET_BAD flag to prevent unexpected bad inode
commit 63b1e9bccb71fe7d7e3ddc9877dbdc85e5d2d023 upstream.

There are many places that will get unhappy (and crash) when ext4_iget()
returns a bad inode. However, if iget the boot loader inode, allows a bad
inode to be returned, because the inode may not be initialized. This
mechanism can be used to bypass some checks and cause panic. To solve this
problem, we add a special iget flag EXT4_IGET_BAD. Only with this flag
we'd be returning bad inode from ext4_iget(), otherwise we always return
the error code if the inode is bad inode.(suggested by Jan Kara)

Signed-off-by: Baokun Li <libaokun1@huawei.com>
Reviewed-by: Jason Yan <yanaijie@huawei.com>
Reviewed-by: Jan Kara <jack@suse.cz>
Link: https://lore.kernel.org/r/20221026042310.3839669-4-libaokun1@huawei.com
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Cc: stable@kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-01-12 11:59:01 +01:00
Baokun Li
cf0e0817b0 ext4: fix use-after-free in ext4_orphan_cleanup
commit a71248b1accb2b42e4980afef4fa4a27fa0e36f5 upstream.

I caught a issue as follows:
==================================================================
 BUG: KASAN: use-after-free in __list_add_valid+0x28/0x1a0
 Read of size 8 at addr ffff88814b13f378 by task mount/710

 CPU: 1 PID: 710 Comm: mount Not tainted 6.1.0-rc3-next #370
 Call Trace:
  <TASK>
  dump_stack_lvl+0x73/0x9f
  print_report+0x25d/0x759
  kasan_report+0xc0/0x120
  __asan_load8+0x99/0x140
  __list_add_valid+0x28/0x1a0
  ext4_orphan_cleanup+0x564/0x9d0 [ext4]
  __ext4_fill_super+0x48e2/0x5300 [ext4]
  ext4_fill_super+0x19f/0x3a0 [ext4]
  get_tree_bdev+0x27b/0x450
  ext4_get_tree+0x19/0x30 [ext4]
  vfs_get_tree+0x49/0x150
  path_mount+0xaae/0x1350
  do_mount+0xe2/0x110
  __x64_sys_mount+0xf0/0x190
  do_syscall_64+0x35/0x80
  entry_SYSCALL_64_after_hwframe+0x63/0xcd
  </TASK>
 [...]
==================================================================

Above issue may happen as follows:
-------------------------------------
ext4_fill_super
  ext4_orphan_cleanup
   --- loop1: assume last_orphan is 12 ---
    list_add(&EXT4_I(inode)->i_orphan, &EXT4_SB(sb)->s_orphan)
    ext4_truncate --> return 0
      ext4_inode_attach_jinode --> return -ENOMEM
    iput(inode) --> free inode<12>
   --- loop2: last_orphan is still 12 ---
    list_add(&EXT4_I(inode)->i_orphan, &EXT4_SB(sb)->s_orphan);
    // use inode<12> and trigger UAF

To solve this issue, we need to propagate the return value of
ext4_inode_attach_jinode() appropriately.

Signed-off-by: Baokun Li <libaokun1@huawei.com>
Reviewed-by: Jan Kara <jack@suse.cz>
Link: https://lore.kernel.org/r/20221102080633.1630225-1-libaokun1@huawei.com
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Cc: stable@kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-01-12 11:59:00 +01:00
Baokun Li
7192afa5e4 ext4: add inode table check in __ext4_get_inode_loc to aovid possible infinite loop
commit eee22187b53611e173161e38f61de1c7ecbeb876 upstream.

In do_writepages, if the value returned by ext4_writepages is "-ENOMEM"
and "wbc->sync_mode == WB_SYNC_ALL", retry until the condition is not met.

In __ext4_get_inode_loc, if the bh returned by sb_getblk is NULL,
the function returns -ENOMEM.

In __getblk_slow, if the return value of grow_buffers is less than 0,
the function returns NULL.

When the three processes are connected in series like the following stack,
an infinite loop may occur:

do_writepages					<--- keep retrying
 ext4_writepages
  mpage_map_and_submit_extent
   mpage_map_one_extent
    ext4_map_blocks
     ext4_ext_map_blocks
      ext4_ext_handle_unwritten_extents
       ext4_ext_convert_to_initialized
        ext4_split_extent
         ext4_split_extent_at
          __ext4_ext_dirty
           __ext4_mark_inode_dirty
            ext4_reserve_inode_write
             ext4_get_inode_loc
              __ext4_get_inode_loc		<--- return -ENOMEM
               sb_getblk
                __getblk_gfp
                 __getblk_slow			<--- return NULL
                  grow_buffers
                   grow_dev_page		<--- return -ENXIO
                    ret = (block < end_block) ? 1 : -ENXIO;

In this issue, bg_inode_table_hi is overwritten as an incorrect value.
As a result, `block < end_block` cannot be met in grow_dev_page.
Therefore, __ext4_get_inode_loc always returns '-ENOMEM' and do_writepages
keeps retrying. As a result, the writeback process is in the D state due
to an infinite loop.

Add a check on inode table block in the __ext4_get_inode_loc function by
referring to ext4_read_inode_bitmap to avoid this infinite loop.

Cc: stable@kernel.org
Signed-off-by: Baokun Li <libaokun1@huawei.com>
Reviewed-by: Ritesh Harjani (IBM) <ritesh.list@gmail.com>
Link: https://lore.kernel.org/r/20220817132701.3015912-3-libaokun1@huawei.com
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-01-12 11:59:00 +01:00
Zhang Yi
0d041b7251 ext4: silence the warning when evicting inode with dioread_nolock
commit bc12ac98ea2e1b70adc6478c8b473a0003b659d3 upstream.

When evicting an inode with default dioread_nolock, it could be raced by
the unwritten extents converting kworker after writeback some new
allocated dirty blocks. It convert unwritten extents to written, the
extents could be merged to upper level and free extent blocks, so it
could mark the inode dirty again even this inode has been marked
I_FREEING. But the inode->i_io_list check and warning in
ext4_evict_inode() missing this corner case. Fortunately,
ext4_evict_inode() will wait all extents converting finished before this
check, so it will not lead to inode use-after-free problem, every thing
is OK besides this warning. The WARN_ON_ONCE was originally designed
for finding inode use-after-free issues in advance, but if we add
current dioread_nolock case in, it will become not quite useful, so fix
this warning by just remove this check.

 ======
 WARNING: CPU: 7 PID: 1092 at fs/ext4/inode.c:227
 ext4_evict_inode+0x875/0xc60
 ...
 RIP: 0010:ext4_evict_inode+0x875/0xc60
 ...
 Call Trace:
  <TASK>
  evict+0x11c/0x2b0
  iput+0x236/0x3a0
  do_unlinkat+0x1b4/0x490
  __x64_sys_unlinkat+0x4c/0xb0
  do_syscall_64+0x3b/0x90
  entry_SYSCALL_64_after_hwframe+0x46/0xb0
 RIP: 0033:0x7fa933c1115b
 ======

rm                          kworker
                            ext4_end_io_end()
vfs_unlink()
 ext4_unlink()
                             ext4_convert_unwritten_io_end_vec()
                              ext4_convert_unwritten_extents()
                               ext4_map_blocks()
                                ext4_ext_map_blocks()
                                 ext4_ext_try_to_merge_up()
                                  __mark_inode_dirty()
                                   check !I_FREEING
                                   locked_inode_to_wb_and_lock_list()
 iput()
  iput_final()
   evict()
    ext4_evict_inode()
     truncate_inode_pages_final() //wait release io_end
                                    inode_io_list_move_locked()
                             ext4_release_io_end()
     trigger WARN_ON_ONCE()

Cc: stable@kernel.org
Fixes: ceff86fddae8 ("ext4: Avoid freeing inodes on dirty list")
Signed-off-by: Zhang Yi <yi.zhang@huawei.com>
Reviewed-by: Jan Kara <jack@suse.cz>
Link: https://lore.kernel.org/r/20220629112647.4141034-1-yi.zhang@huawei.com
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-01-12 11:59:00 +01:00
Jinke Han
d12471b416 ext4: place buffer head allocation before handle start
commit d1052d236eddf6aa851434db1897b942e8db9921 upstream.

In our product environment, we encounter some jbd hung waiting handles to
stop while several writters were doing memory reclaim for buffer head
allocation in delay alloc write path. Ext4 do buffer head allocation with
holding transaction handle which may be blocked too long if the reclaim
works not so smooth. According to our bcc trace, the reclaim time in
buffer head allocation can reach 258s and the jbd transaction commit also
take almost the same time meanwhile. Except for these extreme cases,
we often see several seconds delays for cgroup memory reclaim on our
servers. This is more likely to happen considering docker environment.

One thing to note, the allocation of buffer heads is as often as page
allocation or more often when blocksize less than page size. Just like
page cache allocation, we should also place the buffer head allocation
before startting the handle.

Cc: stable@kernel.org
Signed-off-by: Jinke Han <hanjinke.666@bytedance.com>
Link: https://lore.kernel.org/r/20220903012429.22555-1-hanjinke.666@bytedance.com
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2022-10-26 12:34:29 +02:00
Lukas Czerner
1f5e643b38 ext4: don't increase iversion counter for ea_inodes
commit 50f094a5580e6297bf10a807d16f0ee23fa576cf upstream.

ea_inodes are using i_version for storing part of the reference count so
we really need to leave it alone.

The problem can be reproduced by xfstest ext4/026 when iversion is
enabled. Fix it by not calling inode_inc_iversion() for EXT4_EA_INODE_FL
inodes in ext4_mark_iloc_dirty().

Cc: stable@kernel.org
Signed-off-by: Lukas Czerner <lczerner@redhat.com>
Reviewed-by: Jan Kara <jack@suse.cz>
Reviewed-by: Jeff Layton <jlayton@kernel.org>
Reviewed-by: Christian Brauner (Microsoft) <brauner@kernel.org>
Link: https://lore.kernel.org/r/20220824160349.39664-1-lczerner@redhat.com
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2022-10-26 12:34:29 +02:00
Jan Kara
0b885394fd ext4: remove EA inode entry from mbcache on inode eviction
[ Upstream commit 6bc0d63dad7f9f54d381925ee855b402f652fa39 ]

Currently we remove EA inode from mbcache as soon as its xattr refcount
drops to zero. However there can be pending attempts to reuse the inode
and thus refcount handling code has to handle the situation when
refcount increases from zero anyway. So save some work and just keep EA
inode in mbcache until it is getting evicted. At that moment we are sure
following iget() of EA inode will fail anyway (or wait for eviction to
finish and load things from the disk again) and so removing mbcache
entry at that moment is fine and simplifies the code a bit.

CC: stable@vger.kernel.org
Fixes: 82939d7999df ("ext4: convert to mbcache2")
Signed-off-by: Jan Kara <jack@suse.cz>
Link: https://lore.kernel.org/r/20220712105436.32204-3-jack@suse.cz
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2022-08-17 14:24:27 +02:00
Ye Bin
30dfb75e1f ext4: fix warning in ext4_iomap_begin as race between bmap and write
[ Upstream commit 51ae846cff568c8c29921b1b28eb2dfbcd4ac12d ]

We got issue as follows:
------------[ cut here ]------------
WARNING: CPU: 3 PID: 9310 at fs/ext4/inode.c:3441 ext4_iomap_begin+0x182/0x5d0
RIP: 0010:ext4_iomap_begin+0x182/0x5d0
RSP: 0018:ffff88812460fa08 EFLAGS: 00010293
RAX: ffff88811f168000 RBX: 0000000000000000 RCX: ffffffff97793c12
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000003
RBP: ffff88812c669160 R08: ffff88811f168000 R09: ffffed10258cd20f
R10: ffff88812c669077 R11: ffffed10258cd20e R12: 0000000000000001
R13: 00000000000000a4 R14: 000000000000000c R15: ffff88812c6691ee
FS:  00007fd0d6ff3740(0000) GS:ffff8883af180000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007fd0d6dda290 CR3: 0000000104a62000 CR4: 00000000000006e0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 iomap_apply+0x119/0x570
 iomap_bmap+0x124/0x150
 ext4_bmap+0x14f/0x250
 bmap+0x55/0x80
 do_vfs_ioctl+0x952/0xbd0
 __x64_sys_ioctl+0xc6/0x170
 do_syscall_64+0x33/0x40
 entry_SYSCALL_64_after_hwframe+0x44/0xa9

Above issue may happen as follows:
          bmap                    write
bmap
  ext4_bmap
    iomap_bmap
      ext4_iomap_begin
                            ext4_file_write_iter
			      ext4_buffered_write_iter
			        generic_perform_write
				  ext4_da_write_begin
				    ext4_da_write_inline_data_begin
				      ext4_prepare_inline_data
				        ext4_create_inline_data
					  ext4_set_inode_flag(inode,
						EXT4_INODE_INLINE_DATA);
      if (WARN_ON_ONCE(ext4_has_inline_data(inode))) ->trigger bug_on

To solved above issue hold inode lock in ext4_bamp.

Signed-off-by: Ye Bin <yebin10@huawei.com>
Link: https://lore.kernel.org/r/20220617013935.397596-1-yebin10@huawei.com
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Cc: stable@kernel.org
Signed-off-by: Sasha Levin <sashal@kernel.org>
2022-08-17 14:24:27 +02:00
Baokun Li
9a080f8b08 ext4: correct the misjudgment in ext4_iget_extra_inode
[ Upstream commit fd7e672ea98b95b9d4c9dae316639f03c16a749d ]

Use the EXT4_INODE_HAS_XATTR_SPACE macro to more accurately
determine whether the inode have xattr space.

Cc: stable@kernel.org
Signed-off-by: Baokun Li <libaokun1@huawei.com>
Reviewed-by: Ritesh Harjani (IBM) <ritesh.list@gmail.com>
Reviewed-by: Jan Kara <jack@suse.cz>
Link: https://lore.kernel.org/r/20220616021358.2504451-5-libaokun1@huawei.com
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2022-08-17 14:24:27 +02:00
Eric Whitney
133b80d558 ext4: fix extent status tree race in writeback error recovery path
[ Upstream commit 7f0d8e1d607c1a4fa9a27362a108921d82230874 ]

A race can occur in the unlikely event ext4 is unable to allocate a
physical cluster for a delayed allocation in a bigalloc file system
during writeback.  Failure to allocate a cluster forces error recovery
that includes a call to mpage_release_unused_pages().  That function
removes any corresponding delayed allocated blocks from the extent
status tree.  If a new delayed write is in progress on the same cluster
simultaneously, resulting in the addition of an new extent containing
one or more blocks in that cluster to the extent status tree, delayed
block accounting can be thrown off if that delayed write then encounters
a similar cluster allocation failure during future writeback.

Write lock the i_data_sem in mpage_release_unused_pages() to fix this
problem.  Ext4's block/cluster accounting code for bigalloc relies on
i_data_sem for mutual exclusion, as is found in the delayed write path,
and the locking in mpage_release_unused_pages() is missing.

Cc: stable@kernel.org
Reported-by: Ye Bin <yebin10@huawei.com>
Signed-off-by: Eric Whitney <enwlinux@gmail.com>
Link: https://lore.kernel.org/r/20220615160530.1928801-1-enwlinux@gmail.com
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2022-08-17 14:24:26 +02:00
Ye Bin
b81d2ff688 ext4: fix warning in ext4_handle_inode_extension
commit f4534c9fc94d22383f187b9409abb3f9df2e3db3 upstream.

We got issue as follows:
EXT4-fs error (device loop0) in ext4_reserve_inode_write:5741: Out of memory
EXT4-fs error (device loop0): ext4_setattr:5462: inode #13: comm syz-executor.0: mark_inode_dirty error
EXT4-fs error (device loop0) in ext4_setattr:5519: Out of memory
EXT4-fs error (device loop0): ext4_ind_map_blocks:595: inode #13: comm syz-executor.0: Can't allocate blocks for non-extent mapped inodes with bigalloc
------------[ cut here ]------------
WARNING: CPU: 1 PID: 4361 at fs/ext4/file.c:301 ext4_file_write_iter+0x11c9/0x1220
Modules linked in:
CPU: 1 PID: 4361 Comm: syz-executor.0 Not tainted 5.10.0+ #1
RIP: 0010:ext4_file_write_iter+0x11c9/0x1220
RSP: 0018:ffff924d80b27c00 EFLAGS: 00010282
RAX: ffffffff815a3379 RBX: 0000000000000000 RCX: 000000003b000000
RDX: ffff924d81601000 RSI: 00000000000009cc RDI: 00000000000009cd
RBP: 000000000000000d R08: ffffffffbc5a2c6b R09: 0000902e0e52a96f
R10: ffff902e2b7c1b40 R11: ffff902e2b7c1b40 R12: 000000000000000a
R13: 0000000000000001 R14: ffff902e0e52aa10 R15: ffffffffffffff8b
FS:  00007f81a7f65700(0000) GS:ffff902e3bc80000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: ffffffffff600400 CR3: 000000012db88001 CR4: 00000000003706e0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 do_iter_readv_writev+0x2e5/0x360
 do_iter_write+0x112/0x4c0
 do_pwritev+0x1e5/0x390
 __x64_sys_pwritev2+0x7e/0xa0
 do_syscall_64+0x37/0x50
 entry_SYSCALL_64_after_hwframe+0x44/0xa9

Above issue may happen as follows:
Assume
inode.i_size=4096
EXT4_I(inode)->i_disksize=4096

step 1: set inode->i_isize = 8192
ext4_setattr
  if (attr->ia_size != inode->i_size)
    EXT4_I(inode)->i_disksize = attr->ia_size;
    rc = ext4_mark_inode_dirty
       ext4_reserve_inode_write
          ext4_get_inode_loc
            __ext4_get_inode_loc
              sb_getblk --> return -ENOMEM
   ...
   if (!error)  ->will not update i_size
     i_size_write(inode, attr->ia_size);
Now:
inode.i_size=4096
EXT4_I(inode)->i_disksize=8192

step 2: Direct write 4096 bytes
ext4_file_write_iter
 ext4_dio_write_iter
   iomap_dio_rw ->return error
 if (extend)
   ext4_handle_inode_extension
     WARN_ON_ONCE(i_size_read(inode) < EXT4_I(inode)->i_disksize);
->Then trigger warning.

To solve above issue, if mark inode dirty failed in ext4_setattr just
set 'EXT4_I(inode)->i_disksize' with old value.

Signed-off-by: Ye Bin <yebin10@huawei.com>
Link: https://lore.kernel.org/r/20220326065351.761952-1-yebin10@huawei.com
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Cc: stable@kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2022-06-09 10:23:20 +02:00
Baokun Li
14602353b3 ext4: fix race condition between ext4_write and ext4_convert_inline_data
commit f87c7a4b084afc13190cbb263538e444cb2b392a upstream.

Hulk Robot reported a BUG_ON:
 ==================================================================
 EXT4-fs error (device loop3): ext4_mb_generate_buddy:805: group 0,
 block bitmap and bg descriptor inconsistent: 25 vs 31513 free clusters
 kernel BUG at fs/ext4/ext4_jbd2.c:53!
 invalid opcode: 0000 [#1] SMP KASAN PTI
 CPU: 0 PID: 25371 Comm: syz-executor.3 Not tainted 5.10.0+ #1
 RIP: 0010:ext4_put_nojournal fs/ext4/ext4_jbd2.c:53 [inline]
 RIP: 0010:__ext4_journal_stop+0x10e/0x110 fs/ext4/ext4_jbd2.c:116
 [...]
 Call Trace:
  ext4_write_inline_data_end+0x59a/0x730 fs/ext4/inline.c:795
  generic_perform_write+0x279/0x3c0 mm/filemap.c:3344
  ext4_buffered_write_iter+0x2e3/0x3d0 fs/ext4/file.c:270
  ext4_file_write_iter+0x30a/0x11c0 fs/ext4/file.c:520
  do_iter_readv_writev+0x339/0x3c0 fs/read_write.c:732
  do_iter_write+0x107/0x430 fs/read_write.c:861
  vfs_writev fs/read_write.c:934 [inline]
  do_pwritev+0x1e5/0x380 fs/read_write.c:1031
 [...]
 ==================================================================

Above issue may happen as follows:
           cpu1                     cpu2
__________________________|__________________________
do_pwritev
 vfs_writev
  do_iter_write
   ext4_file_write_iter
    ext4_buffered_write_iter
     generic_perform_write
      ext4_da_write_begin
                           vfs_fallocate
                            ext4_fallocate
                             ext4_convert_inline_data
                              ext4_convert_inline_data_nolock
                               ext4_destroy_inline_data_nolock
                                clear EXT4_STATE_MAY_INLINE_DATA
                               ext4_map_blocks
                                ext4_ext_map_blocks
                                 ext4_mb_new_blocks
                                  ext4_mb_regular_allocator
                                   ext4_mb_good_group_nolock
                                    ext4_mb_init_group
                                     ext4_mb_init_cache
                                      ext4_mb_generate_buddy  --> error
       ext4_test_inode_state(inode, EXT4_STATE_MAY_INLINE_DATA)
                                ext4_restore_inline_data
                                 set EXT4_STATE_MAY_INLINE_DATA
       ext4_block_write_begin
      ext4_da_write_end
       ext4_test_inode_state(inode, EXT4_STATE_MAY_INLINE_DATA)
       ext4_write_inline_data_end
        handle=NULL
        ext4_journal_stop(handle)
         __ext4_journal_stop
          ext4_put_nojournal(handle)
           ref_cnt = (unsigned long)handle
           BUG_ON(ref_cnt == 0)  ---> BUG_ON

The lock held by ext4_convert_inline_data is xattr_sem, but the lock
held by generic_perform_write is i_rwsem. Therefore, the two locks can
be concurrent.

To solve above issue, we add inode_lock() for ext4_convert_inline_data().
At the same time, move ext4_convert_inline_data() in front of
ext4_punch_hole(), remove similar handling from ext4_punch_hole().

Fixes: 0c8d414f163f ("ext4: let fallocate handle inline data correctly")
Cc: stable@vger.kernel.org
Reported-by: Hulk Robot <hulkci@huawei.com>
Signed-off-by: Baokun Li <libaokun1@huawei.com>
Reviewed-by: Jan Kara <jack@suse.cz>
Link: https://lore.kernel.org/r/20220428134031.4153381-1-libaokun1@huawei.com
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2022-06-09 10:23:20 +02:00
Tadeusz Struk
9b90003771 ext4: limit length to bitmap_maxbytes - blocksize in punch_hole
commit 2da376228a2427501feb9d15815a45dbdbdd753e upstream.

Syzbot found an issue [1] in ext4_fallocate().
The C reproducer [2] calls fallocate(), passing size 0xffeffeff000ul,
and offset 0x1000000ul, which, when added together exceed the
bitmap_maxbytes for the inode. This triggers a BUG in
ext4_ind_remove_space(). According to the comments in this function
the 'end' parameter needs to be one block after the last block to be
removed. In the case when the BUG is triggered it points to the last
block. Modify the ext4_punch_hole() function and add constraint that
caps the length to satisfy the one before laster block requirement.

LINK: [1] https://syzkaller.appspot.com/bug?id=b80bd9cf348aac724a4f4dff251800106d721331
LINK: [2] https://syzkaller.appspot.com/text?tag=ReproC&x=14ba0238700000

Fixes: a4bb6b64e39a ("ext4: enable "punch hole" functionality")
Reported-by: syzbot+7a806094edd5d07ba029@syzkaller.appspotmail.com
Signed-off-by: Tadeusz Struk <tadeusz.struk@linaro.org>
Link: https://lore.kernel.org/r/20220331200515.153214-1-tadeusz.struk@linaro.org
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Cc: stable@kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2022-04-27 14:39:01 +02:00
Darrick J. Wong
ba50ea456f ext4: fix fallocate to use file_modified to update permissions consistently
commit ad5cd4f4ee4d5fcdb1bfb7a0c073072961e70783 upstream.

Since the initial introduction of (posix) fallocate back at the turn of
the century, it has been possible to use this syscall to change the
user-visible contents of files.  This can happen by extending the file
size during a preallocation, or through any of the newer modes (punch,
zero, collapse, insert range).  Because the call can be used to change
file contents, we should treat it like we do any other modification to a
file -- update the mtime, and drop set[ug]id privileges/capabilities.

The VFS function file_modified() does all this for us if pass it a
locked inode, so let's make fallocate drop permissions correctly.

Signed-off-by: Darrick J. Wong <djwong@kernel.org>
Link: https://lore.kernel.org/r/20220308185043.GA117678@magnolia
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Cc: stable@kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2022-04-27 14:39:01 +02:00
Theodore Ts'o
a0856764dc ext4: don't BUG if someone dirty pages without asking ext4 first
[ Upstream commit cc5095747edfb054ca2068d01af20be3fcc3634f ]

[un]pin_user_pages_remote is dirtying pages without properly warning
the file system in advance.  A related race was noted by Jan Kara in
2018[1]; however, more recently instead of it being a very hard-to-hit
race, it could be reliably triggered by process_vm_writev(2) which was
discovered by Syzbot[2].

This is technically a bug in mm/gup.c, but arguably ext4 is fragile in
that if some other kernel subsystem dirty pages without properly
notifying the file system using page_mkwrite(), ext4 will BUG, while
other file systems will not BUG (although data will still be lost).

So instead of crashing with a BUG, issue a warning (since there may be
potential data loss) and just mark the page as clean to avoid
unprivileged denial of service attacks until the problem can be
properly fixed.  More discussion and background can be found in the
thread starting at [2].

[1] https://lore.kernel.org/linux-mm/20180103100430.GE4911@quack2.suse.cz
[2] https://lore.kernel.org/r/Yg0m6IjcNmfaSokM@google.com

Reported-by: syzbot+d59332e2db681cf18f0318a06e994ebbb529a8db@syzkaller.appspotmail.com
Reported-by: Lee Jones <lee.jones@linaro.org>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Link: https://lore.kernel.org/r/YiDS9wVfq4mM2jGK@mit.edu
Signed-off-by: Sasha Levin <sashal@kernel.org>
2022-04-08 14:23:57 +02:00
Xin Yin
97abcfedc8 ext4: fast commit may not fallback for ineligible commit
[ Upstream commit e85c81ba8859a4c839bcd69c5d83b32954133a5b ]

For the follow scenario:
1. jbd start commit transaction n
2. task A get new handle for transaction n+1
3. task A do some ineligible actions and mark FC_INELIGIBLE
4. jbd complete transaction n and clean FC_INELIGIBLE
5. task A call fsync

In this case fast commit will not fallback to full commit and
transaction n+1 also not handled by jbd.

Make ext4_fc_mark_ineligible() also record transaction tid for
latest ineligible case, when call ext4_fc_cleanup() check
current transaction tid, if small than latest ineligible tid
do not clear the EXT4_MF_FC_INELIGIBLE.

Reported-by: kernel test robot <lkp@intel.com>
Reported-by: Dan Carpenter <dan.carpenter@oracle.com>
Reported-by: Ritesh Harjani <riteshh@linux.ibm.com>
Suggested-by: Harshad Shirwadkar <harshadshirwadkar@gmail.com>
Signed-off-by: Xin Yin <yinxin.x@bytedance.com>
Link: https://lore.kernel.org/r/20220117093655.35160-2-yinxin.x@bytedance.com
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Cc: stable@kernel.org
Signed-off-by: Sasha Levin <sashal@kernel.org>
2022-03-08 19:12:32 +01:00
Zhang Yi
e58742f46a ext4: fix an use-after-free issue about data=journal writeback mode
commit 5c48a7df91499e371ef725895b2e2d21a126e227 upstream.

Our syzkaller report an use-after-free issue that accessing the freed
buffer_head on the writeback page in __ext4_journalled_writepage(). The
problem is that if there was a truncate racing with the data=journalled
writeback procedure, the writeback length could become zero and
bget_one() refuse to get buffer_head's refcount, then the truncate
procedure release buffer once we drop page lock, finally, the last
ext4_walk_page_buffers() trigger the use-after-free problem.

sync                               truncate
ext4_sync_file()
 file_write_and_wait_range()
                                   ext4_setattr(0)
                                    inode->i_size = 0
  ext4_writepage()
   len = 0
   __ext4_journalled_writepage()
    page_bufs = page_buffers(page)
    ext4_walk_page_buffers(bget_one) <- does not get refcount
                                    do_invalidatepage()
                                      free_buffer_head()
    ext4_walk_page_buffers(page_bufs) <- trigger use-after-free

After commit bdf96838aea6 ("ext4: fix race between truncate and
__ext4_journalled_writepage()"), we have already handled the racing
case, so the bget_one() and bput_one() are not needed. So this patch
simply remove these hunk, and recheck the i_size to make it safe.

Fixes: bdf96838aea6 ("ext4: fix race between truncate and __ext4_journalled_writepage()")
Signed-off-by: Zhang Yi <yi.zhang@huawei.com>
Cc: stable@vger.kernel.org
Link: https://lore.kernel.org/r/20211225090937.712867-1-yi.zhang@huawei.com
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2022-01-27 11:05:18 +01:00
Xin Yin
95fb4c496a ext4: fast commit may miss tracking unwritten range during ftruncate
commit 9725958bb75cdfa10f2ec11526fdb23e7485e8e4 upstream.

If use FALLOC_FL_KEEP_SIZE to alloc unwritten range at bottom, the
inode->i_size will not include the unwritten range. When call
ftruncate with fast commit enabled, it will miss to track the
unwritten range.

Change to trace the full range during ftruncate.

Signed-off-by: Xin Yin <yinxin.x@bytedance.com>
Reviewed-by: Harshad Shirwadkar <harshadshirwadkar@gmail.com>
Link: https://lore.kernel.org/r/20211223032337.5198-3-yinxin.x@bytedance.com
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Cc: stable@kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2022-01-27 11:05:17 +01:00
Xin Yin
50bc43bc1c ext4: fix fast commit may miss tracking range for FALLOC_FL_ZERO_RANGE
commit 5e4d0eba1ccaf19f93222abdeda5a368be141785 upstream.

when call falloc with FALLOC_FL_ZERO_RANGE, to set an range to unwritten,
which has been already initialized. If the range is align to blocksize,
fast commit will not track range for this change.

Also track range for unwritten range in ext4_map_blocks().

Signed-off-by: Xin Yin <yinxin.x@bytedance.com>
Reviewed-by: Harshad Shirwadkar <harshadshirwadkar@gmail.com>
Link: https://lore.kernel.org/r/20211221022839.374606-1-yinxin.x@bytedance.com
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Cc: stable@kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2022-01-27 11:05:16 +01:00
Harshad Shirwadkar
85cc4554ee ext4: initialize err_blk before calling __ext4_get_inode_loc
commit c27c29c6af4f3f4ce925a2111c256733c5a5b430 upstream.

It is not guaranteed that __ext4_get_inode_loc will definitely set
err_blk pointer when it returns EIO. To avoid using uninitialized
variables, let's first set err_blk to 0.

Reported-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Harshad Shirwadkar <harshadshirwadkar@gmail.com>
Link: https://lore.kernel.org/r/20211201163421.2631661-1-harshads@google.com
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Cc: stable@kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2022-01-27 11:05:16 +01:00
Eric Whitney
46fd62b268 Revert "ext4: enforce buffer head state assertion in ext4_da_map_blocks"
commit 3eda41df05d6ad5c825cbc7fef03d563597b1afa upstream.

This reverts commit 948ca5f30e1df0c11eb5b0f410b9ceb97fa77ad9.

Two crash reports from users running variations on 5.15-rc4 kernels
suggest that it is premature to enforce the state assertion in the
original commit.  Both crashes were triggered by BUG calls in that
code, indicating that under some rare circumstance the buffer head
state did not match a delayed allocated block at the time the
block was written out.  No reproducer is available.  Resolving this
problem will require more time than remains in the current release
cycle, so reverting the original patch for the time being is necessary
to avoid any instability it may cause.

Signed-off-by: Eric Whitney <enwlinux@gmail.com>
Link: https://lore.kernel.org/r/20211012171901.5352-1-enwlinux@gmail.com
Fixes: 948ca5f30e1d ("ext4: enforce buffer head state assertion in ext4_da_map_blocks")
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Cc: stable@kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-11-18 19:15:55 +01:00
Linus Torvalds
ca3cef466f Fix a number of ext4 bugs in fast_commit, inline data, and delayed
allocation.  Also fix error handling code paths in ext4_dx_readdir()
 and ext4_fill_super().  Finally, avoid a grabbing a journal head in
 the delayed allocation write in the common cases where we are
 overwriting an pre-existing block or appending to an inode.
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Merge tag 'ext4_for_linus_stable' of git://git.kernel.org/pub/scm/linux/kernel/git/tytso/ext4

Pull ext4 fixes from Ted Ts'o:
 "Fix a number of ext4 bugs in fast_commit, inline data, and delayed
  allocation.

  Also fix error handling code paths in ext4_dx_readdir() and
  ext4_fill_super().

  Finally, avoid a grabbing a journal head in the delayed allocation
  write in the common cases where we are overwriting a pre-existing
  block or appending to an inode"

* tag 'ext4_for_linus_stable' of git://git.kernel.org/pub/scm/linux/kernel/git/tytso/ext4:
  ext4: recheck buffer uptodate bit under buffer lock
  ext4: fix potential infinite loop in ext4_dx_readdir()
  ext4: flush s_error_work before journal destroy in ext4_fill_super
  ext4: fix loff_t overflow in ext4_max_bitmap_size()
  ext4: fix reserved space counter leakage
  ext4: limit the number of blocks in one ADD_RANGE TLV
  ext4: enforce buffer head state assertion in ext4_da_map_blocks
  ext4: remove extent cache entries when truncating inline data
  ext4: drop unnecessary journal handle in delalloc write
  ext4: factor out write end code of inline file
  ext4: correct the error path of ext4_write_inline_data_end()
  ext4: check and update i_disksize properly
  ext4: add error checking to ext4_ext_replay_set_iblocks()
2021-10-03 13:56:53 -07:00
Zhang Yi
f2c7797350 ext4: recheck buffer uptodate bit under buffer lock
Commit 8e33fadf945a ("ext4: remove an unnecessary if statement in
__ext4_get_inode_loc()") forget to recheck buffer's uptodate bit again
under buffer lock, which may overwrite the buffer if someone else have
already brought it uptodate and changed it.

Fixes: 8e33fadf945a ("ext4: remove an unnecessary if statement in __ext4_get_inode_loc()")
Cc: stable@kernel.org
Signed-off-by: Zhang Yi <yi.zhang@huawei.com>
Reviewed-by: Jan Kara <jack@suse.cz>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Link: https://lore.kernel.org/r/20210910080316.70421-1-yi.zhang@huawei.com
2021-10-01 00:10:28 -04:00
Jeffle Xu
6fed83957f ext4: fix reserved space counter leakage
When ext4_insert_delayed block receives and recovers from an error from
ext4_es_insert_delayed_block(), e.g., ENOMEM, it does not release the
space it has reserved for that block insertion as it should. One effect
of this bug is that s_dirtyclusters_counter is not decremented and
remains incorrectly elevated until the file system has been unmounted.
This can result in premature ENOSPC returns and apparent loss of free
space.

Another effect of this bug is that
/sys/fs/ext4/<dev>/delayed_allocation_blocks can remain non-zero even
after syncfs has been executed on the filesystem.

Besides, add check for s_dirtyclusters_counter when inode is going to be
evicted and freed. s_dirtyclusters_counter can still keep non-zero until
inode is written back in .evict_inode(), and thus the check is delayed
to .destroy_inode().

Fixes: 51865fda28e5 ("ext4: let ext4 maintain extent status tree")
Cc: stable@kernel.org
Suggested-by: Gao Xiang <hsiangkao@linux.alibaba.com>
Signed-off-by: Jeffle Xu <jefflexu@linux.alibaba.com>
Reviewed-by: Eric Whitney <enwlinux@gmail.com>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Link: https://lore.kernel.org/r/20210823061358.84473-1-jefflexu@linux.alibaba.com
2021-10-01 00:03:41 -04:00
Eric Whitney
948ca5f30e ext4: enforce buffer head state assertion in ext4_da_map_blocks
Remove the code that re-initializes a buffer head with an invalid block
number and BH_New and BH_Delay bits when a matching delayed and
unwritten block has been found in the extent status cache. Replace it
with assertions that verify the buffer head already has this state
correctly set.  The current code masked an inline data truncation bug
that left stale entries in the extent status cache.  With this change,
generic/130 can be used to reproduce and detect that bug.

Signed-off-by: Eric Whitney <enwlinux@gmail.com>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Link: https://lore.kernel.org/r/20210819144927.25163-3-enwlinux@gmail.com
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2021-09-09 10:52:05 -04:00
Theodore Ts'o
11ef08c9eb Merge branch 'delalloc-buffer-write' into dev
Fix a bug in how we update i_disksize, and the error path in
inline_data_end.  Finally, drop an unnecessary creation of a journal
handle which was only needed for inline data, which can give us a
large performance gain in delayed allocation writes.

Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2021-09-09 10:47:06 -04:00
Zhang Yi
cc883236b7 ext4: drop unnecessary journal handle in delalloc write
After we factor out the inline data write procedure from
ext4_da_write_end(), we don't need to start journal handle for the cases
of both buffer overwrite and append-write. If we need to update
i_disksize, mark_inode_dirty() do start handle and update inode buffer.
So we could just remove all the journal handle codes in the delalloc
write procedure.

After this patch, we could get a lot of performance improvement. Below
is the Unixbench comparison data test on my machine with 'Intel Xeon
Gold 5120' CPU and nvme SSD backend.

Test cmd:

  ./Run -c 56 -i 3 fstime fsbuffer fsdisk

Before this patch:

  System Benchmarks Partial Index           BASELINE       RESULT   INDEX
  File Copy 1024 bufsize 2000 maxblocks       3960.0     422965.0   1068.1
  File Copy 256 bufsize 500 maxblocks         1655.0     105077.0   634.9
  File Copy 4096 bufsize 8000 maxblocks       5800.0    1429092.0   2464.0
                                                                    ======
  System Benchmarks Index Score (Partial Only)                      1186.6

After this patch:

  System Benchmarks Partial Index           BASELINE       RESULT   INDEX
  File Copy 1024 bufsize 2000 maxblocks       3960.0     732716.0   1850.3
  File Copy 256 bufsize 500 maxblocks         1655.0     184940.0   1117.5
  File Copy 4096 bufsize 8000 maxblocks       5800.0    2427152.0   4184.7
                                                                    ======
  System Benchmarks Index Score (Partial Only)                      2053.0

Signed-off-by: Zhang Yi <yi.zhang@huawei.com>
Reviewed-by: Jan Kara <jack@suse.cz>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Link: https://lore.kernel.org/r/20210716122024.1105856-5-yi.zhang@huawei.com
2021-09-04 23:38:18 -04:00
Zhang Yi
6984aef598 ext4: factor out write end code of inline file
Now that the inline_data file write end procedure are falled into the
common write end functions, it is not clear. Factor them out and do
some cleanup. This patch also drop ext4_da_write_inline_data_end()
and switch to use ext4_write_inline_data_end() instead because we also
need to do the same error processing if we failed to write data into
inline entry.

Signed-off-by: Zhang Yi <yi.zhang@huawei.com>
Reviewed-by: Jan Kara <jack@suse.cz>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Link: https://lore.kernel.org/r/20210716122024.1105856-4-yi.zhang@huawei.com
2021-09-04 23:38:18 -04:00
Zhang Yi
55ce2f649b ext4: correct the error path of ext4_write_inline_data_end()
Current error path of ext4_write_inline_data_end() is not correct.

Firstly, it should pass out the error value if ext4_get_inode_loc()
return fail, or else it could trigger infinite loop if we inject error
here. And then it's better to add inode to orphan list if it return fail
in ext4_journal_stop(), otherwise we could not restore inline xattr
entry after power failure. Finally, we need to reset the 'ret' value if
ext4_write_inline_data_end() return success in ext4_write_end() and
ext4_journalled_write_end(), otherwise we could not get the error return
value of ext4_journal_stop().

Signed-off-by: Zhang Yi <yi.zhang@huawei.com>
Reviewed-by: Jan Kara <jack@suse.cz>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Link: https://lore.kernel.org/r/20210716122024.1105856-3-yi.zhang@huawei.com
2021-09-04 23:38:18 -04:00
Zhang Yi
4df031ff58 ext4: check and update i_disksize properly
After commit 3da40c7b0898 ("ext4: only call ext4_truncate when size <=
isize"), i_disksize could always be updated to i_size in ext4_setattr(),
and we could sure that i_disksize <= i_size since holding inode lock and
if i_disksize < i_size there are delalloc writes pending in the range
upto i_size. If the end of the current write is <= i_size, there's no
need to touch i_disksize since writeback will push i_disksize upto
i_size eventually. So we can switch to check i_size instead of
i_disksize in ext4_da_write_end() when write to the end of the file.
we also could remove ext4_mark_inode_dirty() together because we defer
inode dirtying to generic_write_end() or ext4_da_write_inline_data_end().

Signed-off-by: Zhang Yi <yi.zhang@huawei.com>
Reviewed-by: Jan Kara <jack@suse.cz>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Link: https://lore.kernel.org/r/20210716122024.1105856-2-yi.zhang@huawei.com
2021-09-04 23:38:18 -04:00
Linus Torvalds
111c1aa8ca In addition to some ext4 bug fixes and cleanups, this cycle we add the
orphan_file feature, which eliminates bottlenecks when doing a large
 number of parallel truncates and file deletions, and move the discard
 operation out of the jbd2 commit thread when using the discard mount
 option, to better support devices with slow discard operations.
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Merge tag 'ext4_for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tytso/ext4

Pull ext4 updates from Ted Ts'o:
 "In addition to some ext4 bug fixes and cleanups, this cycle we add the
  orphan_file feature, which eliminates bottlenecks when doing a large
  number of parallel truncates and file deletions, and move the discard
  operation out of the jbd2 commit thread when using the discard mount
  option, to better support devices with slow discard operations"

* tag 'ext4_for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tytso/ext4: (23 commits)
  ext4: make the updating inode data procedure atomic
  ext4: remove an unnecessary if statement in __ext4_get_inode_loc()
  ext4: move inode eio simulation behind io completeion
  ext4: Improve scalability of ext4 orphan file handling
  ext4: Orphan file documentation
  ext4: Speedup ext4 orphan inode handling
  ext4: Move orphan inode handling into a separate file
  ext4: Support for checksumming from journal triggers
  ext4: fix race writing to an inline_data file while its xattrs are changing
  jbd2: add sparse annotations for add_transaction_credits()
  ext4: fix sparse warnings
  ext4: Make sure quota files are not grabbed accidentally
  ext4: fix e2fsprogs checksum failure for mounted filesystem
  ext4: if zeroout fails fall back to splitting the extent node
  ext4: reduce arguments of ext4_fc_add_dentry_tlv
  ext4: flush background discard kwork when retry allocation
  ext4: get discard out of jbd2 commit kthread contex
  ext4: remove the repeated comment of ext4_trim_all_free
  ext4: add new helper interface ext4_try_to_trim_range()
  ext4: remove the 'group' parameter of ext4_trim_extent
  ...
2021-09-02 09:37:09 -07:00
Zhang Yi
baaae979b1 ext4: make the updating inode data procedure atomic
Now that ext4_do_update_inode() return error before filling the whole
inode data if we fail to set inode blocks in ext4_inode_blocks_set().
This error should never happen in theory since sb->s_maxbytes should not
have allowed this, we have already init sb->s_maxbytes according to this
feature in ext4_fill_super(). So even through that could only happen due
to the filesystem corruption, we'd better to return after we finish
updating the inode because it may left an uninitialized buffer and we
could read this buffer later in "errors=continue" mode.

This patch make the updating inode data procedure atomic, call
EXT4_ERROR_INODE() after we dropping i_raw_lock after something bad
happened, make sure that the inode is integrated, and also drop a BUG_ON
and do some small cleanups.

Signed-off-by: Zhang Yi <yi.zhang@huawei.com>
Reviewed-by: Jan Kara <jack@suse.cz>
Link: https://lore.kernel.org/r/20210826130412.3921207-4-yi.zhang@huawei.com
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2021-08-30 23:36:51 -04:00
Zhang Yi
8e33fadf94 ext4: remove an unnecessary if statement in __ext4_get_inode_loc()
The "if (!buffer_uptodate(bh))" hunk covered almost the whole code after
getting buffer in __ext4_get_inode_loc() which seems unnecessary, remove
it and switch to check ext4_buffer_uptodate(), it simplify code and make
it more readable.

Signed-off-by: Zhang Yi <yi.zhang@huawei.com>
Reviewed-by: Jan Kara <jack@suse.cz>
Link: https://lore.kernel.org/r/20210826130412.3921207-3-yi.zhang@huawei.com
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2021-08-30 23:36:51 -04:00
Zhang Yi
0904c9ae34 ext4: move inode eio simulation behind io completeion
No EIO simulation is required if the buffer is uptodate, so move the
simulation behind read bio completeion just like inode/block bitmap
simulation does.

Signed-off-by: Zhang Yi <yi.zhang@huawei.com>
Reviewed-by: Jan Kara <jack@suse.cz>
Link: https://lore.kernel.org/r/20210826130412.3921207-2-yi.zhang@huawei.com
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2021-08-30 23:36:51 -04:00
Jan Kara
02f310fcf4 ext4: Speedup ext4 orphan inode handling
Ext4 orphan inode handling is a bottleneck for workloads which heavily
truncate / unlink small files since it contends on the global
s_orphan_mutex lock (and generally it's difficult to improve scalability
of the ondisk linked list of orphaned inodes).

This patch implements new way of handling orphan inodes. Instead of
linking orphaned inode into a linked list, we store it's inode number in
a new special file which we call "orphan file". Only if there's no more
space in the orphan file (too many inodes are currently orphaned) we
fall back to using old style linked list. Currently we protect
operations in the orphan file with a spinlock for simplicity but even in
this setting we can substantially reduce the length of the critical
section and thus speedup some workloads. In the next patch we improve
this by making orphan handling lockless.

Note that the change is backwards compatible when the filesystem is
clean - the existence of the orphan file is a compat feature, we set
another ro-compat feature indicating orphan file needs scanning for
orphaned inodes when mounting filesystem read-write. This ro-compat
feature gets cleared on unmount / remount read-only.

Some performance data from 80 CPU Xeon Server with 512 GB of RAM,
filesystem located on SSD, average of 5 runs:

stress-orphan (microbenchmark truncating files byte-by-byte from N
processes in parallel)

Threads Time            Time
        Vanilla         Patched
  1       1.057200        0.945600
  2       1.680400        1.331800
  4       2.547000        1.995000
  8       7.049400        6.424200
 16      14.827800       14.937600
 32      40.948200       33.038200
 64      87.787400       60.823600
128     206.504000      122.941400

So we can see significant wins all over the board.

Reviewed-by: Theodore Ts'o <tytso@mit.edu>
Signed-off-by: Jan Kara <jack@suse.cz>
Link: https://lore.kernel.org/r/20210816095713.16537-3-jack@suse.cz
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2021-08-30 23:36:51 -04:00
Jan Kara
188c299e2a ext4: Support for checksumming from journal triggers
JBD2 layer support triggers which are called when journaling layer moves
buffer to a certain state. We can use the frozen trigger, which gets
called when buffer data is frozen and about to be written out to the
journal, to compute block checksums for some buffer types (similarly as
does ocfs2). This avoids unnecessary repeated recomputation of the
checksum (at the cost of larger window where memory corruption won't be
caught by checksumming) and is even necessary when there are
unsynchronized updaters of the checksummed data.

So add superblock and journal trigger type arguments to
ext4_journal_get_write_access() and ext4_journal_get_create_access() so
that frozen triggers can be set accordingly. Also add inode argument to
ext4_walk_page_buffers() and all the callbacks used with that function
for the same purpose. This patch is mostly only a change of prototype of
the above mentioned functions and a few small helpers. Real checksumming
will come later.

Reviewed-by: Theodore Ts'o <tytso@mit.edu>
Signed-off-by: Jan Kara <jack@suse.cz>
Link: https://lore.kernel.org/r/20210816095713.16537-1-jack@suse.cz
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2021-08-30 23:36:50 -04:00
Jan Kara
bd2c38cf17 ext4: Make sure quota files are not grabbed accidentally
If ext4 filesystem is corrupted so that quota files are linked from
directory hirerarchy, bad things can happen. E.g. quota files can get
corrupted or deleted. Make sure we are not grabbing quota file inodes
when we expect normal inodes.

Signed-off-by: Jan Kara <jack@suse.cz>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Link: https://lore.kernel.org/r/20210812133122.26360-1-jack@suse.cz
2021-08-30 23:36:50 -04:00
Jan Kara
d4f5258eae ext4: Convert to use mapping->invalidate_lock
Convert ext4 to use mapping->invalidate_lock instead of its private
EXT4_I(inode)->i_mmap_sem. This is mostly search-and-replace. By this
conversion we fix a long standing race between hole punching and read(2)
/ readahead(2) paths that can lead to stale page cache contents.

CC: <linux-ext4@vger.kernel.org>
CC: Ted Tso <tytso@mit.edu>
Acked-by: Theodore Ts'o <tytso@mit.edu>
Reviewed-by: Darrick J. Wong <djwong@kernel.org>
Signed-off-by: Jan Kara <jack@suse.cz>
2021-07-13 14:29:00 +02:00