linux-stable.git/fs/ext4/inline.c, branch v4.14.166

ext4: fix a potential fiemap/page fault deadlock w/ inline_data

2019-01-16T21:07:12+00:00

commit 2b08b1f12cd664dc7d5c84ead9ff25ae97ad5491 upstream.

The ext4_inline_data_fiemap() function calls fiemap_fill_next_extent()
while still holding the xattr semaphore.  This is not necessary and it
triggers a circular lockdep warning.  This is because
fiemap_fill_next_extent() could trigger a page fault when it writes
into page which triggers a page fault.  If that page is mmaped from
the inline file in question, this could very well result in a
deadlock.

This problem can be reproduced using generic/519 with a file system
configuration which has the inline_data feature enabled.

Signed-off-by: Theodore Ts'o 
Cc: stable@kernel.org
Signed-off-by: Greg Kroah-Hartman

ext4: missing unlock/put_page() in ext4_try_to_write_inline_data()

2019-01-09T16:14:49+00:00

commit 132d00becb31e88469334e1e62751c81345280e0 upstream.

In case of error, ext4_try_to_write_inline_data() should unlock
and release the page it holds.

Fixes: f19d5870cbf7 ("ext4: add normal write support for inline data")
Cc: stable@kernel.org # 3.8
Signed-off-by: Maurizio Lombardi 
Signed-off-by: Theodore Ts'o 
Signed-off-by: Greg Kroah-Hartman

ext4: initialize retries variable in ext4_da_write_inline_data_begin()

2018-11-13T19:15:06+00:00

commit 625ef8a3acd111d5f496d190baf99d1a815bd03e upstream.

Variable retries is not initialized in ext4_da_write_inline_data_begin()
which can lead to nondeterministic number of retries in case we hit
ENOSPC. Initialize retries to zero as we do everywhere else.

Signed-off-by: Lukas Czerner 
Signed-off-by: Theodore Ts'o 
Fixes: bc0ca9df3b2a ("ext4: retry allocation when inline->extent conversion failed")
Cc: stable@kernel.org
Signed-off-by: Greg Kroah-Hartman

ext4: avoid divide by zero fault when deleting corrupted inline directories

2018-09-29T10:06:06+00:00

commit 4d982e25d0bdc83d8c64e66fdeca0b89240b3b85 upstream.

A specially crafted file system can trick empty_inline_dir() into
reading past the last valid entry in a inline directory, and then run
into the end of xattr marker. This will trigger a divide by zero
fault.  Fix this by using the size of the inline directory instead of
dir->i_size.

Also clean up error reporting in __ext4_check_dir_entry so that the
message is clearer and more understandable --- and avoids the division
by zero trap if the size passed in is zero.  (I'm not sure why we
coded it that way in the first place; printing offset % size is
actually more confusing and less useful.)

https://bugzilla.kernel.org/show_bug.cgi?id=200933

Signed-off-by: Theodore Ts'o 
Reported-by: Wen Xu 
Cc: stable@vger.kernel.org
Signed-off-by: Greg Kroah-Hartman

ext4: fix inline data updates with checksums enabled

2018-08-03T05:50:43+00:00

commit 362eca70b53389bddf3143fe20f53dcce2cfdf61 upstream.

The inline data code was updating the raw inode directly; this is
problematic since if metadata checksums are enabled,
ext4_mark_inode_dirty() must be called to update the inode's checksum.
In addition, the jbd2 layer requires that get_write_access() be called
before the metadata buffer is modified.  Fix both of these problems.

https://bugzilla.kernel.org/show_bug.cgi?id=200443

Signed-off-by: Theodore Ts'o 
Cc: stable@vger.kernel.org
Signed-off-by: Greg Kroah-Hartman

ext4: avoid running out of journal credits when appending to an inline file

2018-07-11T14:29:18+00:00

commit 8bc1379b82b8e809eef77a9fedbb75c6c297be19 upstream.

Use a separate journal transaction if it turns out that we need to
convert an inline file to use an data block.  Otherwise we could end
up failing due to not having journal credits.

This addresses CVE-2018-10883.

https://bugzilla.kernel.org/show_bug.cgi?id=200071

Signed-off-by: Theodore Ts'o 
Cc: stable@kernel.org
Signed-off-by: Greg Kroah-Hartman

ext4: clear i_data in ext4_inode_info when removing inline data

2018-07-11T14:29:18+00:00

commit 6e8ab72a812396996035a37e5ca4b3b99b5d214b upstream.

When converting from an inode from storing the data in-line to a data
block, ext4_destroy_inline_data_nolock() was only clearing the on-disk
copy of the i_blocks[] array.  It was not clearing copy of the
i_blocks[] in ext4_inode_info, in i_data[], which is the copy actually
used by ext4_map_blocks().

This didn't matter much if we are using extents, since the extents
header would be invalid and thus the extents could would re-initialize
the extents tree.  But if we are using indirect blocks, the previous
contents of the i_blocks array will be treated as block numbers, with
potentially catastrophic results to the file system integrity and/or
user data.

This gets worse if the file system is using a 1k block size and
s_first_data is zero, but even without this, the file system can get
quite badly corrupted.

This addresses CVE-2018-10881.

https://bugzilla.kernel.org/show_bug.cgi?id=200015

Signed-off-by: Theodore Ts'o 
Cc: stable@kernel.org
Signed-off-by: Greg Kroah-Hartman

ext4: do not allow external inodes for inline data

2018-06-26T00:06:29+00:00

commit 117166efb1ee8f13c38f9e96b258f16d4923f888 upstream.

The inline data feature was implemented before we added support for
external inodes for xattrs.  It makes no sense to support that
combination, but the problem is that there are a number of extended
attribute checks that are skipped if e_value_inum is non-zero.

Unfortunately, the inline data code is completely e_value_inum
unaware, and attempts to interpret the xattr fields as if it were an
inline xattr --- at which point, Hilarty Ensues.

This addresses CVE-2018-11412.

https://bugzilla.kernel.org/show_bug.cgi?id=199803

Reported-by: Jann Horn 
Reviewed-by: Andreas Dilger 
Signed-off-by: Theodore Ts'o 
Fixes: e50e5129f384 ("ext4: xattr-in-inode support")
Cc: stable@kernel.org
Signed-off-by: Greg Kroah-Hartman

ext4: prevent data corruption with inline data + DAX

2017-11-30T08:40:48+00:00

commit 559db4c6d784ceedc2a5418ced4d357cb843e221 upstream.

If an inode has inline data it is currently prevented from using DAX by a
check in ext4_set_inode_flags().  When the inode grows inline data via
ext4_create_inline_data() or removes its inline data via
ext4_destroy_inline_data_nolock(), the value of S_DAX can change.

Currently these changes are unsafe because we don't hold off page faults
and I/O, write back dirty radix tree entries and invalidate all mappings.
There are also issues with mm-level races when changing the value of S_DAX,
as well as issues with the VM_MIXEDMAP flag:

https://www.spinics.net/lists/linux-xfs/msg09859.html

The unsafe transition of S_DAX can reliably cause data corruption, as shown
by the following fstest:

https://patchwork.kernel.org/patch/9948381/

Fix this issue by preventing the DAX mount option from being used on
filesystems that were created to support inline data.  Inline data is an
option given to mkfs.ext4.

Signed-off-by: Ross Zwisler 
Signed-off-by: Theodore Ts'o 
Reviewed-by: Jan Kara 
Signed-off-by: Greg Kroah-Hartman

ext4: xattr-in-inode support

2017-06-22T01:10:32+00:00

Large xattr support is implemented for EXT4_FEATURE_INCOMPAT_EA_INODE.

If the size of an xattr value is larger than will fit in a single
external block, then the xattr value will be saved into the body
of an external xattr inode.

The also helps support a larger number of xattr, since only the headers
will be stored in the in-inode space or the single external block.

The inode is referenced from the xattr header via "e_value_inum",
which was formerly "e_value_block", but that field was never used.
The e_value_size still contains the xattr size so that listing
xattrs does not need to look up the inode if the data is not accessed.

struct ext4_xattr_entry {
        __u8    e_name_len;     /* length of name */
        __u8    e_name_index;   /* attribute name index */
        __le16  e_value_offs;   /* offset in disk block of value */
        __le32  e_value_inum;   /* inode in which value is stored */
        __le32  e_value_size;   /* size of attribute value */
        __le32  e_hash;         /* hash value of name and value */
        char    e_name[0];      /* attribute name */
};

The xattr inode is marked with the EXT4_EA_INODE_FL flag and also
holds a back-reference to the owning inode in its i_mtime field,
allowing the ext4/e2fsck to verify the correct inode is accessed.

[ Applied fix by Dan Carpenter to avoid freeing an ERR_PTR. ]

Lustre-Jira: https://jira.hpdd.intel.com/browse/LU-80
Lustre-bugzilla: https://bugzilla.lustre.org/show_bug.cgi?id=4424
Signed-off-by: Kalpak Shah 
Signed-off-by: James Simmons 
Signed-off-by: Andreas Dilger 
Signed-off-by: Tahsin Erdogan 
Signed-off-by: Theodore Ts'o 
Signed-off-by: Dan Carpenter