linux-stable.git/fs, branch v5.4.4

ext4: fix leak of quota reservations

2019-12-17T18:56:53+00:00

commit f4c2d372b89a1e504ebb7b7eb3e29b8306479366 upstream.

Commit 8fcc3a580651 ("ext4: rework reserved cluster accounting when
invalidating pages") moved freeing of delayed allocation reservations
from dirty page invalidation time to time when we evict corresponding
status extent from extent status tree. For inodes which don't have any
blocks allocated this may actually happen only in ext4_clear_blocks()
which is after we've dropped references to quota structures from the
inode. Thus reservation of quota leaked. Fix the problem by clearing
quota information from the inode only after evicting extent status tree
in ext4_clear_inode().

Link: https://lore.kernel.org/r/20191108115420.GI20863@quack2.suse.cz
Reported-by: Konstantin Khlebnikov 
Fixes: 8fcc3a580651 ("ext4: rework reserved cluster accounting when invalidating pages")
Signed-off-by: Jan Kara 
Signed-off-by: Theodore Ts'o 
Signed-off-by: Greg Kroah-Hartman

ext4: fix a bug in ext4_wait_for_tail_page_commit

2019-12-17T18:56:53+00:00

commit 565333a1554d704789e74205989305c811fd9c7a upstream.

No need to wait for any commit once the page is fully truncated.
Besides, it may confuse e.g. concurrent ext4_writepage() with the page
still be dirty (will be cleared by truncate_pagecache() in
ext4_setattr()) but buffers has been freed; and then trigger a bug
show as below:

[   26.057508] ------------[ cut here ]------------
[   26.058531] kernel BUG at fs/ext4/inode.c:2134!
...
[   26.088130] Call trace:
[   26.088695]  ext4_writepage+0x914/0xb28
[   26.089541]  writeout.isra.4+0x1b4/0x2b8
[   26.090409]  move_to_new_page+0x3b0/0x568
[   26.091338]  __unmap_and_move+0x648/0x988
[   26.092241]  unmap_and_move+0x48c/0xbb8
[   26.093096]  migrate_pages+0x220/0xb28
[   26.093945]  kernel_mbind+0x828/0xa18
[   26.094791]  __arm64_sys_mbind+0xc8/0x138
[   26.095716]  el0_svc_common+0x190/0x490
[   26.096571]  el0_svc_handler+0x60/0xd0
[   26.097423]  el0_svc+0x8/0xc

Run the procedure (generate by syzkaller) parallel with ext3.

void main()
{
	int fd, fd1, ret;
	void *addr;
	size_t length = 4096;
	int flags;
	off_t offset = 0;
	char *str = "12345";

	fd = open("a", O_RDWR | O_CREAT);
	assert(fd >= 0);

	/* Truncate to 4k */
	ret = ftruncate(fd, length);
	assert(ret == 0);

	/* Journal data mode */
	flags = 0xc00f;
	ret = ioctl(fd, _IOW('f', 2, long), &flags);
	assert(ret == 0);

	/* Truncate to 0 */
	fd1 = open("a", O_TRUNC | O_NOATIME);
	assert(fd1 >= 0);

	addr = mmap(NULL, length, PROT_WRITE | PROT_READ,
					MAP_SHARED, fd, offset);
	assert(addr != (void *)-1);

	memcpy(addr, str, 5);
	mbind(addr, length, 0, 0, 0, MPOL_MF_MOVE);
}

And the bug will be triggered once we seen the below order.

reproduce1                         reproduce2

...                            |   ...
truncate to 4k                 |
change to journal data mode    |
                               |   memcpy(set page dirty)
truncate to 0:                 |
ext4_setattr:                  |
...                            |
ext4_wait_for_tail_page_commit |
                               |   mbind(trigger bug)
truncate_pagecache(clean dirty)|   ...
...                            |

mbind will call ext4_writepage() since the page still be dirty, and then
report the bug since the buffers has been free. Fix it by return
directly once offset equals to 0 which means the page has been fully
truncated.

Reported-by: Hulk Robot 
Signed-off-by: yangerkun 
Link: https://lore.kernel.org/r/20190919063508.1045-1-yangerkun@huawei.com
Reviewed-by: Jan Kara 
Signed-off-by: Theodore Ts'o 
Signed-off-by: Greg Kroah-Hartman

splice: only read in as much information as there is pipe buffer space

2019-12-17T18:56:52+00:00

commit 3253d9d093376d62b4a56e609f15d2ec5085ac73 upstream.

Andreas Grünbacher reports that on the two filesystems that support
iomap directio, it's possible for splice() to return -EAGAIN (instead of
a short splice) if the pipe being written to has less space available in
its pipe buffers than the length supplied by the calling process.

Months ago we fixed splice_direct_to_actor to clamp the length of the
read request to the size of the splice pipe.  Do the same to do_splice.

Fixes: 17614445576b6 ("splice: don't read more than available pipe space")
Reported-by: syzbot+3c01db6025f26530cf8d@syzkaller.appspotmail.com
Reported-by: Andreas Grünbacher 
Reviewed-by: Andreas Grünbacher 
Signed-off-by: Darrick J. Wong 
Signed-off-by: Greg Kroah-Hartman

ext4: work around deleting a file with i_nlink == 0 safely

2019-12-17T18:56:49+00:00

commit c7df4a1ecb8579838ec8c56b2bb6a6716e974f37 upstream.

If the file system is corrupted such that a file's i_links_count is
too small, then it's possible that when unlinking that file, i_nlink
will already be zero.  Previously we were working around this kind of
corruption by forcing i_nlink to one; but we were doing this before
trying to delete the directory entry --- and if the file system is
corrupted enough that ext4_delete_entry() fails, then we exit with
i_nlink elevated, and this causes the orphan inode list handling to be
FUBAR'ed, such that when we unmount the file system, the orphan inode
list can get corrupted.

A better way to fix this is to simply skip trying to call drop_nlink()
if i_nlink is already zero, thus moving the check to the place where
it makes the most sense.

https://bugzilla.kernel.org/show_bug.cgi?id=205433

Link: https://lore.kernel.org/r/20191112032903.8828-1-tytso@mit.edu
Signed-off-by: Theodore Ts'o 
Cc: stable@kernel.org
Reviewed-by: Andreas Dilger 
Signed-off-by: Greg Kroah-Hartman

reiserfs: fix extended attributes on the root directory

2019-12-17T18:56:44+00:00

commit 60e4cf67a582d64f07713eda5fcc8ccdaf7833e6 upstream.

Since commit d0a5b995a308 (vfs: Add IOP_XATTR inode operations flag)
extended attributes haven't worked on the root directory in reiserfs.

This is due to reiserfs conditionally setting the sb->s_xattrs handler
array depending on whether it located or create the internal privroot
directory.  It necessarily does this after the root inode is already
read in.  The IOP_XATTR flag is set during inode initialization, so
it never gets set on the root directory.

This commit unconditionally assigns sb->s_xattrs and clears IOP_XATTR on
internal inodes.  The old return values due to the conditional assignment
are handled via open_xa_root, which now returns EOPNOTSUPP as the VFS
would have done.

Link: https://lore.kernel.org/r/20191024143127.17509-1-jeffm@suse.com
CC: stable@vger.kernel.org
Fixes: d0a5b995a308 ("vfs: Add IOP_XATTR inode operations flag")
Signed-off-by: Jeff Mahoney 
Signed-off-by: Jan Kara 
Signed-off-by: Greg Kroah-Hartman

ext4: Fix credit estimate for final inode freeing

2019-12-17T18:56:44+00:00

commit 65db869c754e7c271691dd5feabf884347e694f5 upstream.

Estimate for the number of credits needed for final freeing of inode in
ext4_evict_inode() was to small. We may modify 4 blocks (inode & sb for
orphan deletion, bitmap & group descriptor for inode freeing) and not
just 3.

[ Fixed minor whitespace nit. -- TYT ]

Fixes: e50e5129f384 ("ext4: xattr-in-inode support")
CC: stable@vger.kernel.org
Signed-off-by: Jan Kara 
Link: https://lore.kernel.org/r/20191105164437.32602-6-jack@suse.cz
Signed-off-by: Theodore Ts'o 
Signed-off-by: Greg Kroah-Hartman

quota: fix livelock in dquot_writeback_dquots

2019-12-17T18:56:43+00:00

commit 6ff33d99fc5c96797103b48b7b0902c296f09c05 upstream.

Write only quotas which are dirty at entry.

XFSTEST: https://github.com/dmonakhov/xfstests/commit/b10ad23566a5bf75832a6f500e1236084083cddc

Link: https://lore.kernel.org/r/20191031103920.3919-1-dmonakhov@openvz.org
CC: stable@vger.kernel.org
Signed-off-by: Konstantin Khlebnikov 
Signed-off-by: Dmitry Monakhov 
Signed-off-by: Jan Kara 
Signed-off-by: Greg Kroah-Hartman

ext2: check err when partial != NULL

2019-12-17T18:56:43+00:00

commit e705f4b8aa27a59f8933e8f384e9752f052c469c upstream.

Check err when partial == NULL is meaningless because
partial == NULL means getting branch successfully without
error.

CC: stable@vger.kernel.org
Link: https://lore.kernel.org/r/20191105045100.7104-1-cgxu519@mykernel.net
Signed-off-by: Chengguang Xu 
Signed-off-by: Jan Kara 
Signed-off-by: Greg Kroah-Hartman

quota: Check that quota is not dirty before release

2019-12-17T18:56:43+00:00

commit df4bb5d128e2c44848aeb36b7ceceba3ac85080d upstream.

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: https://github.com/dmonakhov/xfstests/commit/440a80d4cbb39e9234df4d7240aee1d551c36107

Link: https://lore.kernel.org/r/20191031103920.3919-2-dmonakhov@openvz.org
CC: stable@vger.kernel.org
Signed-off-by: Dmitry Monakhov 
Signed-off-by: Jan Kara 
Signed-off-by: Greg Kroah-Hartman

erofs: zero out when listxattr is called with no xattr

2019-12-17T18:56:23+00:00

commit 926d1650176448d7684b991fbe1a5b1a8289e97c upstream.

As David reported [1], ENODATA returns when attempting
to modify files by using EROFS as an overlayfs lower layer.

The root cause is that listxattr could return unexpected
-ENODATA by mistake for inodes without xattr. That breaks
listxattr return value convention and it can cause copy
up failure when used with overlayfs.

Resolve by zeroing out if no xattr is found for listxattr.

[1] https://lore.kernel.org/r/CAEvUa7nxnby+rxK-KRMA46=exeOMApkDMAV08AjMkkPnTPV4CQ@mail.gmail.com
Link: https://lore.kernel.org/r/20191201084040.29275-1-hsiangkao@aol.com
Fixes: cadf1ccf1b00 ("staging: erofs: add error handling for xattr submodule")
Cc:  # 4.19+
Reviewed-by: Chao Yu 
Signed-off-by: Gao Xiang 
Signed-off-by: Greg Kroah-Hartman