linux/fs/btrfs
Filipe Manana 5f5bc6b1e2 Btrfs: make xattr replace operations atomic
Replacing a xattr consists of doing a lookup for its existing value, delete
the current value from the respective leaf, release the search path and then
finally insert the new value. This leaves a time window where readers (getxattr,
listxattrs) won't see any value for the xattr. Xattrs are used to store ACLs,
so this has security implications.

This change also fixes 2 other existing issues which were:

*) Deleting the old xattr value without verifying first if the new xattr will
   fit in the existing leaf item (in case multiple xattrs are packed in the
   same item due to name hash collision);

*) Returning -EEXIST when the flag XATTR_CREATE is given and the xattr doesn't
   exist but we have have an existing item that packs muliple xattrs with
   the same name hash as the input xattr. In this case we should return ENOSPC.

A test case for xfstests follows soon.

Thanks to Alexandre Oliva for reporting the non-atomicity of the xattr replace
implementation.

Reported-by: Alexandre Oliva <oliva@gnu.org>
Signed-off-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: Chris Mason <clm@fb.com>
2014-11-20 17:20:07 -08:00
..
tests Btrfs: remove empty block groups automatically 2014-09-22 17:13:21 -07:00
acl.c btrfs: remove useless ACL check 2014-06-09 17:20:42 -07:00
async-thread.c btrfs: remove unlikely from NULL checks 2014-10-02 16:06:19 +02:00
async-thread.h Btrfs: implement repair function when direct read fails 2014-09-17 13:39:01 -07:00
backref.c btrfs: remove parameter blocksize from read_tree_block 2014-10-02 17:14:50 +02:00
backref.h Btrfs: make fiemap not blow when you have lots of snapshots 2014-09-17 13:38:24 -07:00
btrfs_inode.h Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mason/linux-btrfs 2014-10-11 08:03:52 -04:00
check-integrity.c Btrfs: check-int: don't complain about balanced blocks 2014-11-20 17:14:30 -08:00
check-integrity.h
compression.c Btrfs: don't ignore compressed bio write errors 2014-11-20 17:14:26 -08:00
compression.h
ctree.c Btrfs: make xattr replace operations atomic 2014-11-20 17:20:07 -08:00
ctree.h Btrfs: make xattr replace operations atomic 2014-11-20 17:20:07 -08:00
delayed-inode.c btrfs: kill the key type accessor helpers 2014-09-17 13:37:12 -07:00
delayed-inode.h
delayed-ref.c Btrfs: rework qgroup accounting 2014-06-09 17:20:48 -07:00
delayed-ref.h Btrfs: rework qgroup accounting 2014-06-09 17:20:48 -07:00
dev-replace.c Btrfs: return failure if btrfs_dev_replace_finishing() failed 2014-11-20 17:14:28 -08:00
dev-replace.h
dir-item.c Btrfs: make xattr replace operations atomic 2014-11-20 17:20:07 -08:00
disk-io.c btrfs: fix typos in btrfs_check_super_valid 2014-11-20 17:20:03 -08:00
disk-io.h Merge branch 'cleanup/blocksize-diet-part1' of git://git.kernel.org/pub/scm/linux/kernel/git/kdave/linux into for-linus 2014-10-04 09:57:14 -07:00
export.c btrfs: kill the key type accessor helpers 2014-09-17 13:37:12 -07:00
export.h
extent_io.c Btrfs: avoid premature -ENOMEM in clear_extent_bit() 2014-11-20 17:20:06 -08:00
extent_io.h Btrfs: set page and mapping error on compressed write failure 2014-11-20 17:14:25 -08:00
extent_map.c Btrfs: fix NULL pointer crash when running balance and scrub concurrently 2014-06-19 14:20:55 -07:00
extent_map.h Btrfs: fix NULL pointer crash when running balance and scrub concurrently 2014-06-19 14:20:55 -07:00
extent-tree.c Btrfs: move read only block groups onto their own list V2 2014-11-20 17:20:04 -08:00
file-item.c Btrfs: fix kfree on list_head in btrfs_lookup_csums_range error cleanup 2014-11-04 06:59:04 -08:00
file.c Btrfs: add helper btrfs_fdatawrite_range 2014-11-20 17:14:28 -08:00
free-space-cache.c Btrfs: improve free space cache management and space allocation 2014-09-17 13:38:13 -07:00
free-space-cache.h
hash.c btrfs: LLVMLinux: Remove VLAIS 2014-10-14 10:51:22 +02:00
hash.h
inode-item.c btrfs: kill the key type accessor helpers 2014-09-17 13:37:12 -07:00
inode-map.c btrfs: cleanup ino cache members of btrfs_root 2014-09-17 13:37:09 -07:00
inode-map.h
inode.c Btrfs: report error after failure inlining extent in compressed write path 2014-11-20 17:14:28 -08:00
ioctl.c vfs: export check_sticky() 2014-10-24 00:14:36 +02:00
Kconfig
locking.c Btrfs: fix deadlocks with trylock on tree nodes 2014-06-19 14:19:55 -07:00
locking.h
lzo.c btrfs: use DIV_ROUND_UP instead of open-coded variants 2014-09-17 13:37:17 -07:00
Makefile Btrfs: add sanity tests for new qgroup accounting code 2014-06-09 17:20:49 -07:00
math.h
ordered-data.c Btrfs: add helper btrfs_fdatawrite_range 2014-11-20 17:14:28 -08:00
ordered-data.h btrfs: disable strict file flushes for renames and truncates 2014-08-15 07:43:42 -07:00
orphan.c btrfs: kill the key type accessor helpers 2014-09-17 13:37:12 -07:00
print-tree.c btrfs: remove parameter blocksize from read_tree_block 2014-10-02 17:14:50 +02:00
print-tree.h
props.c
props.h
qgroup.c btrfs: move checks for DUMMY_ROOT into a helper 2014-10-02 17:30:33 +02:00
qgroup.h btrfs: qgroup: account shared subtrees during snapshot delete 2014-08-15 07:43:14 -07:00
raid56.c btrfs: use DIV_ROUND_UP instead of open-coded variants 2014-09-17 13:37:17 -07:00
raid56.h
rcu-string.h
reada.c btrfs: use nodesize everywhere, kill leafsize 2014-09-17 13:37:14 -07:00
relocation.c Merge branch 'cleanup/blocksize-diet-part1' of git://git.kernel.org/pub/scm/linux/kernel/git/kdave/linux into for-linus 2014-10-04 09:57:14 -07:00
root-tree.c Btrfs: use bitfield instead of integer data type for the some variants in btrfs_root 2014-06-09 17:20:40 -07:00
scrub.c btrfs: remove unused members from struct scrub_warning 2014-10-02 17:30:30 +02:00
send.c Merge branch 'cleanup/misc-for-3.18' of git://git.kernel.org/pub/scm/linux/kernel/git/kdave/linux into for-linus 2014-10-04 09:56:45 -07:00
send.h
struct-funcs.c
super.c Btrfs: don't take the chunk_mutex/dev_list mutex in statfs V2 2014-11-20 17:20:05 -08:00
sysfs.c btrfs: sysfs label interface should check for read only FS 2014-09-17 13:38:01 -07:00
sysfs.h btrfs: code optimize: BTRFS_ATTR_RW could set the mode 2014-09-17 13:37:59 -07:00
transaction.c Btrfs: make find_first_extent_bit be able to cache any state 2014-11-20 17:14:29 -08:00
transaction.h Btrfs: deal with convert_extent_bit errors to avoid fs corruption 2014-11-20 17:14:29 -08:00
tree-defrag.c Btrfs: use bitfield instead of integer data type for the some variants in btrfs_root 2014-06-09 17:20:40 -07:00
tree-log.c Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mason/linux-btrfs 2014-11-01 10:41:26 -07:00
tree-log.h Btrfs: fix data corruption after fast fsync and writeback error 2014-09-19 06:57:51 -07:00
ulist.c
ulist.h Btrfs: Fix memory corruption by ulist_add_merge() on 32bit arch 2014-08-15 07:43:19 -07:00
uuid-tree.c Btrfs: make btrfs_search_forward return with nodes unlocked 2014-09-17 13:38:02 -07:00
volumes.c Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mason/linux-btrfs 2014-10-11 08:03:52 -04:00
volumes.h Btrfs: remove empty block groups automatically 2014-09-22 17:13:21 -07:00
xattr.c Btrfs: make xattr replace operations atomic 2014-11-20 17:20:07 -08:00
xattr.h
zlib.c btrfs compression: merge inflate and deflate z_streams 2014-09-17 13:37:33 -07:00