linux-toradex.git/fs/ext4/xattr.c, branch v3.18-rc5

ext4: Replace open coded mdata csum feature to helper function

2014-10-13T07:36:16+00:00

Besides the fact that this replacement improves code readability
it also protects from errors caused direct EXT4_S(sb)->s_es manipulation
which may result attempt to use uninitialized  csum machinery.

#Testcase_BEGIN
IMG=/dev/ram0
MNT=/mnt
mkfs.ext4 $IMG
mount $IMG $MNT
#Enable feature directly on disk, on mounted fs
tune2fs -O metadata_csum  $IMG
# Provoke metadata update, likey result in OOPS
touch $MNT/test
umount $MNT
#Testcase_END

# Replacement script
@@
expression E;
@@
- EXT4_HAS_RO_COMPAT_FEATURE(E, EXT4_FEATURE_RO_COMPAT_METADATA_CSUM)
+ ext4_has_metadata_csum(E)

https://bugzilla.kernel.org/show_bug.cgi?id=82201

Signed-off-by: Dmitry Monakhov 
Signed-off-by: Theodore Ts'o 
Cc: stable@vger.kernel.org

ext4: check EA value offset when loading

2014-09-16T18:34:59+00:00

When loading extended attributes, check each entry's value offset to
make sure it doesn't collide with the entries.

Without this check it is easy to crash the kernel by mounting a
malicious FS containing a file with an EA wherein e_value_offs = 0 and
e_value_size > 0 and then deleting the EA, which corrupts the name
list.

(See the f_ea_value_crash test's FS image in e2fsprogs for an example.)

Signed-off-by: Darrick J. Wong 
Signed-off-by: Theodore Ts'o 
Cc: stable@vger.kernel.org

ext4: prepare to drop EXT4_STATE_DELALLOC_RESERVED

2014-09-04T22:07:25+00:00

The EXT4_STATE_DELALLOC_RESERVED flag was originally implemented
because it was too hard to make sure the mballoc and get_block flags
could be reliably passed down through all of the codepaths that end up
calling ext4_mb_new_blocks().

Since then, we have mb_flags passed down through most of the code
paths, so getting rid of EXT4_STATE_DELALLOC_RESERVED isn't as tricky
as it used to.

This commit plumbs in the last of what is required, and then adds a
WARN_ON check to make sure we haven't missed anything.  If this passes
a full regression test run, we can then drop
EXT4_STATE_DELALLOC_RESERVED.

Signed-off-by: Theodore Ts'o 
Reviewed-by: Jan Kara

ext4: add missing BUFFER_TRACE before ext4_journal_get_write_access

2014-05-13T02:06:43+00:00

Make them more consistently

Signed-off-by: xieliang 
Signed-off-by: "Theodore Ts'o"

ext4: remove unnecessary double parentheses

2014-05-12T16:55:07+00:00

Signed-off-by: Lukas Czerner 
Signed-off-by: "Theodore Ts'o"

ext4: avoid unneeded lookup when xattr name is invalid

2014-05-12T13:57:59+00:00

In ext4_xattr_set_handle() we have checked the xattr name's length. So
we should also check it in ext4_xattr_get() to avoid unneeded lookup
caused by invalid name.

Signed-off-by: Zhang Zhen 
Signed-off-by: "Theodore Ts'o"

ext4: fix jbd2 warning under heavy xattr load

2014-04-07T14:54:21+00:00

When heavily exercising xattr code the assertion that
jbd2_journal_dirty_metadata() shouldn't return error was triggered:

WARNING: at /srv/autobuild-ceph/gitbuilder.git/build/fs/jbd2/transaction.c:1237
jbd2_journal_dirty_metadata+0x1ba/0x260()

CPU: 0 PID: 8877 Comm: ceph-osd Tainted: G    W 3.10.0-ceph-00049-g68d04c9 #1
Hardware name: Dell Inc. PowerEdge R410/01V648, BIOS 1.6.3 02/07/2011
 ffffffff81a1d3c8 ffff880214469928 ffffffff816311b0 ffff880214469968
 ffffffff8103fae0 ffff880214469958 ffff880170a9dc30 ffff8802240fbe80
 0000000000000000 ffff88020b366000 ffff8802256e7510 ffff880214469978
Call Trace:
 [] dump_stack+0x19/0x1b
 [] warn_slowpath_common+0x70/0xa0
 [] warn_slowpath_null+0x1a/0x20
 [] jbd2_journal_dirty_metadata+0x1ba/0x260
 [] __ext4_handle_dirty_metadata+0xa3/0x140
 [] ext4_xattr_release_block+0x103/0x1f0
 [] ext4_xattr_block_set+0x1e0/0x910
 [] ext4_xattr_set_handle+0x38b/0x4a0
 [] ? trace_hardirqs_on+0xd/0x10
 [] ext4_xattr_set+0xc2/0x140
 [] ext4_xattr_user_set+0x47/0x50
 [] generic_setxattr+0x6e/0x90
 [] __vfs_setxattr_noperm+0x7b/0x1c0
 [] vfs_setxattr+0xc4/0xd0
 [] setxattr+0x13e/0x1e0
 [] ? __sb_start_write+0xe7/0x1b0
 [] ? mnt_want_write_file+0x28/0x60
 [] ? fget_light+0x3c/0x130
 [] ? mnt_want_write_file+0x28/0x60
 [] ? __mnt_want_write+0x58/0x70
 [] SyS_fsetxattr+0xbe/0x100
 [] system_call_fastpath+0x16/0x1b

The reason for the warning is that buffer_head passed into
jbd2_journal_dirty_metadata() didn't have journal_head attached. This is
caused by the following race of two ext4_xattr_release_block() calls:

CPU1                                CPU2
ext4_xattr_release_block()          ext4_xattr_release_block()
lock_buffer(bh);
/* False */
if (BHDR(bh)->h_refcount == cpu_to_le32(1))
} else {
  le32_add_cpu(&BHDR(bh)->h_refcount, -1);
  unlock_buffer(bh);
                                    lock_buffer(bh);
                                    /* True */
                                    if (BHDR(bh)->h_refcount == cpu_to_le32(1))
                                      get_bh(bh);
                                      ext4_free_blocks()
                                        ...
                                        jbd2_journal_forget()
                                          jbd2_journal_unfile_buffer()
                                          -> JH is gone
  error = ext4_handle_dirty_xattr_block(handle, inode, bh);
  -> triggers the warning

We fix the problem by moving ext4_handle_dirty_xattr_block() under the
buffer lock. Sadly this cannot be done in nojournal mode as that
function can call sync_dirty_buffer() which would deadlock. Luckily in
nojournal mode the race is harmless (we only dirty already freed buffer)
and thus for nojournal mode we leave the dirtying outside of the buffer
lock.

Reported-by: Sage Weil 
Signed-off-by: Jan Kara 
Signed-off-by: "Theodore Ts'o" 
Cc: stable@vger.kernel.org

ext4: each filesystem creates and uses its own mb_cache

2014-03-18T23:24:49+00:00

This patch adds new interfaces to create and destory cache,
ext4_xattr_create_cache() and ext4_xattr_destroy_cache(), and remove
the cache creation and destory calls from ex4_init_xattr() and
ext4_exitxattr() in fs/ext4/xattr.c.

fs/ext4/super.c has been changed so that when a filesystem is mounted
a cache is allocated and attched to its ext4_sb_info structure.

fs/mbcache.c has been changed so that only one slab allocator is
allocated and used by all mbcache structures.

Signed-off-by: T. Makphaibulchoke

ext4: don't calculate total xattr header size unless needed

2014-02-20T01:15:21+00:00

The function ext4_expand_extra_isize_ea() doesn't need the size of all
of the extended attribute headers.  So if we don't calculate it when
it is unneeded, it we can skip some undeeded memory references, and as
a bonus, we eliminate some kvetching by static code analysis tools.

Addresses-Coverity-Id: #741291

Signed-off-by: "Theodore Ts'o"

ext2/3/4: use generic posix ACL infrastructure

2014-01-26T04:58:19+00:00

Signed-off-by: Christoph Hellwig 
Reviewed-by: Jan Kara 
Signed-off-by: Al Viro