ext4: do not try to set xattr into ea_inode if value is empty

commit 6b22489911b726eebbf169caee52fea52013fbdd upstream.

Syzbot report a warning that ext4 may create an empty ea_inode if set
an empt

ext4: do not try to set xattr into ea_inode if value is empty

commit 6b22489911b726eebbf169caee52fea52013fbdd upstream.

Syzbot report a warning that ext4 may create an empty ea_inode if set
an empty extent attribute to a file on the file system which is no free
blocks left.

WARNING: CPU: 6 PID: 10667 at fs/ext4/xattr.c:1640 ext4_xattr_set_entry+0x10f8/0x1114 fs/ext4/xattr.c:1640
...
Call trace:
ext4_xattr_set_entry+0x10f8/0x1114 fs/ext4/xattr.c:1640
ext4_xattr_block_set+0x1d0/0x1b1c fs/ext4/xattr.c:1942
ext4_xattr_set_handle+0x8a0/0xf1c fs/ext4/xattr.c:2390
ext4_xattr_set+0x120/0x1f0 fs/ext4/xattr.c:2491
ext4_xattr_trusted_set+0x48/0x5c fs/ext4/xattr_trusted.c:37
__vfs_setxattr+0x208/0x23c fs/xattr.c:177
...

Now, ext4 try to store extent attribute into an external inode if
ext4_xattr_block_set() return -ENOSPC, but for the case of store an
empty extent attribute, store the extent entry into the extent
attribute block is enough. A simple reproduce below.

fallocate test.img -l 1M
mkfs.ext4 -F -b 2048 -O ea_inode test.img
mount test.img /mnt
dd if=/dev/zero of=/mnt/foo bs=2048 count=500
setfattr -n "user.test" /mnt/foo

Reported-by: syzbot+98b881fdd8ebf45ab4ae@syzkaller.appspotmail.com
Fixes: 9c6e7853c531 ("ext4: reserve space for xattr entries/names")
Cc: stable@kernel.org
Signed-off-by: zhangyi (F) <yi.zhang@huawei.com>
Link: https://lore.kernel.org/r/20210305120508.298465-1-yi.zhang@huawei.com
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

show more ...

ext4: main fast-commit commit path

This patch adds main fast commit commit path handlers. The overall
patch can be divided into two inter-related parts:

(A) Metadata updates tracking

This part

ext4: main fast-commit commit path

This patch adds main fast commit commit path handlers. The overall
patch can be divided into two inter-related parts:

(A) Metadata updates tracking

This part consists of helper functions to track changes that need
to be committed during a commit operation. These updates are
maintained by Ext4 in different in-memory queues. Following are
the APIs and their short description that are implemented in this
patch:

- ext4_fc_track_link/unlink/creat() - Track unlink. link and creat
operations
- ext4_fc_track_range() - Track changed logical block offsets
inodes
- ext4_fc_track_inode() - Track inodes
- ext4_fc_mark_ineligible() - Mark file system fast commit
ineligible()
- ext4_fc_start_update() / ext4_fc_stop_update() /
ext4_fc_start_ineligible() / ext4_fc_stop_ineligible() These
functions are useful for co-ordinating inode updates with
commits.

(B) Main commit Path

This part consists of functions to convert updates tracked in
in-memory data structures into on-disk commits. Function
ext4_fc_commit() is the main entry point to commit path.

Reported-by: kernel test robot <lkp@intel.com>
Signed-off-by: Harshad Shirwadkar <harshadshirwadkar@gmail.com>
Link: https://lore.kernel.org/r/20201015203802.3597742-6-harshadshirwadkar@gmail.com
Signed-off-by: Theodore Ts'o <tytso@mit.edu>

show more ...

ext4: delete unnecessary checks before brelse()

The brelse() function tests whether its argument is NULL
and then returns immediately.
Thus remove the tests which are not needed around the shown cal

ext4: delete unnecessary checks before brelse()

The brelse() function tests whether its argument is NULL
and then returns immediately.
Thus remove the tests which are not needed around the shown calls.

This issue was detected by using the Coccinelle software.

Signed-off-by: Markus Elfring <elfring@users.sourceforge.net>
Reviewed-by: Ritesh Harjani <riteshh@linux.ibm.com>
Link: https://lore.kernel.org/r/0d713702-072f-a89c-20ec-ca70aa83a432@web.de
Signed-off-by: Theodore Ts'o <tytso@mit.edu>

show more ...

ext4: support xattr gnu.* namespace for the Hurd

The Hurd gained[0] support for moving the translator and author
fields out of the inode and into the "gnu.*" xattr namespace.

In anticipation of tha

ext4: support xattr gnu.* namespace for the Hurd

The Hurd gained[0] support for moving the translator and author
fields out of the inode and into the "gnu.*" xattr namespace.

In anticipation of that, an xattr INDEX was reserved[1]. The Hurd has
now been brought into compliance[2] with that.

This patch adds support for reading and writing such attributes from
Linux; you can now do something like

mkdir -p hurd-root/servers/socket
touch hurd-root/servers/socket/1
setfattr --name=gnu.translator --value='"/hurd/pflocal\0"' \
hurd-root/servers/socket/1
getfattr --name=gnu.translator hurd-root/servers/socket/1
# file: 1
gnu.translator="/hurd/pflocal"

to setup a pipe translator, which is being used to create[3] a
vm-image for the Hurd from GNU Guix.

[0] https://summerofcode.withgoogle.com/projects/#5869799859027968
[1] https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=3980bd3b406addb327d858aebd19e229ea340b9a
[2] https://git.savannah.gnu.org/cgit/hurd/hurd.git/commit/?id=a04c7bf83172faa7cb080fbe3b6c04a8415ca645
[3] https://git.savannah.gnu.org/cgit/guix.git/log/?h=wip-hurd-vm

Signed-off-by: Jan Nieuwenhuizen <janneke@gnu.org>
Link: https://lore.kernel.org/r/20200525193940.878-1-janneke@gnu.org
Signed-off-by: Theodore Ts'o <tytso@mit.edu>

show more ...

ext4: handle ext4_mark_inode_dirty errors

ext4_mark_inode_dirty() can fail for real reasons. Ignoring its return
value may lead ext4 to ignore real failures that would result in
corruption / crashes

ext4: handle ext4_mark_inode_dirty errors

ext4_mark_inode_dirty() can fail for real reasons. Ignoring its return
value may lead ext4 to ignore real failures that would result in
corruption / crashes. Harden ext4_mark_inode_dirty error paths to fail
as soon as possible and return errors to the caller whenever
appropriate.

One of the possible scnearios when this bug could affected is that
while creating a new inode, its directory entry gets added
successfully but while writing the inode itself mark_inode_dirty
returns error which is ignored. This would result in inconsistency
that the directory entry points to a non-existent inode.

Ran gce-xfstests smoke tests and verified that there were no
regressions.

Signed-off-by: Harshad Shirwadkar <harshadshirwadkar@gmail.com>
Link: https://lore.kernel.org/r/20200427013438.219117-1-harshadshirwadkar@gmail.com
Signed-off-by: Theodore Ts'o <tytso@mit.edu>

show more ...

ext4: fix error pointer dereference

Don't pass error pointers to brelse().

commit 7159a986b420 ("ext4: fix some error pointer dereferences") has fixed
some cases, fix the remaining one case.

Once

ext4: fix error pointer dereference

Don't pass error pointers to brelse().

commit 7159a986b420 ("ext4: fix some error pointer dereferences") has fixed
some cases, fix the remaining one case.

Once ext4_xattr_block_find()->ext4_sb_bread() failed, error pointer is
stored in @bs->bh, which will be passed to brelse() in the cleanup
routine of ext4_xattr_set_handle(). This will then cause a NULL panic
crash in __brelse().

BUG: unable to handle kernel NULL pointer dereference at 000000000000005b
RIP: 0010:__brelse+0x1b/0x50
Call Trace:
ext4_xattr_set_handle+0x163/0x5d0
ext4_xattr_set+0x95/0x110
__vfs_setxattr+0x6b/0x80
__vfs_setxattr_noperm+0x68/0x1b0
vfs_setxattr+0xa0/0xb0
setxattr+0x12c/0x1a0
path_setxattr+0x8d/0xc0
__x64_sys_setxattr+0x27/0x30
do_syscall_64+0x60/0x250
entry_SYSCALL_64_after_hwframe+0x49/0xbe

In this case, @bs->bh stores '-EIO' actually.

Fixes: fb265c9cb49e ("ext4: add ext4_sb_bread() to disambiguate ENOMEM cases")
Signed-off-by: Jeffle Xu <jefflexu@linux.alibaba.com>
Reviewed-by: Joseph Qi <joseph.qi@linux.alibaba.com>
Cc: stable@kernel.org # 2.6.19
Reviewed-by: Ritesh Harjani <riteshh@linux.ibm.com>
Reviewed-by: Jan Kara <jack@suse.cz>
Link: https://lore.kernel.org/r/1587628004-95123-1-git-send-email-jefflexu@linux.alibaba.com
Signed-off-by: Theodore Ts'o <tytso@mit.edu>

show more ...

ext4: save all error info in save_error_info() and drop ext4_set_errno()

Using a separate function, ext4_set_errno() to set the errno is
problematic because it doesn't do the right thing once
s_last

ext4: save all error info in save_error_info() and drop ext4_set_errno()

Using a separate function, ext4_set_errno() to set the errno is
problematic because it doesn't do the right thing once
s_last_error_errorcode is non-zero. It's also less racy to set all of
the error information all at once. (Also, as a bonus, it shrinks code
size slightly.)

Link: https://lore.kernel.org/r/20200329020404.686965-1-tytso@mit.edu
Fixes: 878520ac45f9 ("ext4: save the error code which triggered...")
Signed-off-by: Theodore Ts'o <tytso@mit.edu>

show more ...

ext4: drop ext4_kvmalloc()

As Jan pointed out[1], as of commit 81378da64de ("jbd2: mark the
transaction context with the scope GFP_NOFS context") we use
memalloc_nofs_{save,restore}() while a jbd2 h

ext4: drop ext4_kvmalloc()

As Jan pointed out[1], as of commit 81378da64de ("jbd2: mark the
transaction context with the scope GFP_NOFS context") we use
memalloc_nofs_{save,restore}() while a jbd2 handle is active. So
ext4_kvmalloc() so we can call allocate using GFP_NOFS is no longer
necessary.

[1] https://lore.kernel.org/r/20200109100007.GC27035@quack2.suse.cz

Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Link: https://lore.kernel.org/r/20200116155031.266620-1-tytso@mit.edu
Reviewed-by: Jan Kara <jack@suse.cz>

show more ...

ext4: save the error code which triggered an ext4_error() in the superblock

This allows the cause of an ext4_error() report to be categorized
based on whether it was triggered due to an I/O error, o

ext4: save the error code which triggered an ext4_error() in the superblock

This allows the cause of an ext4_error() report to be categorized
based on whether it was triggered due to an I/O error, or an memory
allocation error, or other possible causes. Most errors are caused by
a detected file system inconsistency, so the default code stored in
the superblock will be EXT4_ERR_EFSCORRUPTED.

Link: https://lore.kernel.org/r/20191204032335.7683-1-tytso@mit.edu
Signed-off-by: Theodore Ts'o <tytso@mit.edu>

show more ...

ext4: Reserve revoke credits for freed blocks

So far we have reserved only relatively high fixed amount of revoke
credits for each transaction. We over-reserved by large amount for most
cases but wh

ext4: Reserve revoke credits for freed blocks

So far we have reserved only relatively high fixed amount of revoke
credits for each transaction. We over-reserved by large amount for most
cases but when freeing large directories or files with data journalling,
the fixed amount is not enough. In fact the worst case estimate is
inconveniently large (maximum extent size) for freeing of one extent.

We fix this by doing proper estimate of the amount of blocks that need
to be revoked when removing blocks from the inode due to truncate or
hole punching and otherwise reserve just a small amount of revoke
credits for each transaction to accommodate freeing of xattrs block or
so.

Signed-off-by: Jan Kara <jack@suse.cz>
Link: https://lore.kernel.org/r/20191105164437.32602-23-jack@suse.cz
Signed-off-by: Theodore Ts'o <tytso@mit.edu>

show more ...

ext4, jbd2: Provide accessor function for handle credits

Provide accessor function to get number of credits available in a handle
and use it from ext4. Later, computation of available credits won't

ext4, jbd2: Provide accessor function for handle credits

Provide accessor function to get number of credits available in a handle
and use it from ext4. Later, computation of available credits won't be
so straightforward.

Reviewed-by: Theodore Ts'o <tytso@mit.edu>
Signed-off-by: Jan Kara <jack@suse.cz>
Link: https://lore.kernel.org/r/20191105164437.32602-11-jack@suse.cz
Signed-off-by: Theodore Ts'o <tytso@mit.edu>

show more ...

ext4: Provide function to handle transaction restarts

Provide ext4_journal_ensure_credits_fn() function to ensure transaction
has given amount of credits and call helper function to prepare for
rest

ext4: Provide function to handle transaction restarts

Provide ext4_journal_ensure_credits_fn() function to ensure transaction
has given amount of credits and call helper function to prepare for
restarting a transaction. This allows to remove some boilerplate code
from various places, add proper error handling for the case where
transaction extension or restart fails, and reduces following changes
needed for proper revoke record reservation tracking.

Signed-off-by: Jan Kara <jack@suse.cz>
Link: https://lore.kernel.org/r/20191105164437.32602-10-jack@suse.cz
Signed-off-by: Theodore Ts'o <tytso@mit.edu>

show more ...

ext4: ignore e_value_offs for xattrs with value-in-ea-inode

In other places in fs/ext4/xattr.c, if e_value_inum is non-zero, the
code ignores the value in e_value_offs. The e_value_offs *should* be

ext4: ignore e_value_offs for xattrs with value-in-ea-inode

In other places in fs/ext4/xattr.c, if e_value_inum is non-zero, the
code ignores the value in e_value_offs. The e_value_offs *should* be
zero, but we shouldn't depend upon it, since it might not be true in a
corrupted/fuzzed file system.

Bugzilla: https://bugzilla.kernel.org/show_bug.cgi?id=202897
Bugzilla: https://bugzilla.kernel.org/show_bug.cgi?id=202877
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Cc: stable@kernel.org

show more ...

ext4: fix some error pointer dereferences

We can't pass error pointers to brelse().

Fixes: fb265c9cb49e ("ext4: add ext4_sb_bread() to disambiguate ENOMEM cases")
Signed-off-by: Dan Carpenter <dan.

ext4: fix some error pointer dereferences

We can't pass error pointers to brelse().

Fixes: fb265c9cb49e ("ext4: add ext4_sb_bread() to disambiguate ENOMEM cases")
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Reviewed-by: Jan Kara <jack@suse.cz>

show more ...

ext4: avoid declaring fs inconsistent due to invalid file handles

If we receive a file handle, either from NFS or open_by_handle_at(2),
and it points at an inode which has not been initialized, and

ext4: avoid declaring fs inconsistent due to invalid file handles

If we receive a file handle, either from NFS or open_by_handle_at(2),
and it points at an inode which has not been initialized, and the file
system has metadata checksums enabled, we shouldn't try to get the
inode, discover the checksum is invalid, and then declare the file
system as being inconsistent.

This can be reproduced by creating a test file system via "mke2fs -t
ext4 -O metadata_csum /tmp/foo.img 8M", mounting it, cd'ing into that
directory, and then running the following program.

#define _GNU_SOURCE
#include <fcntl.h>

struct handle {
struct file_handle fh;
unsigned char fid[MAX_HANDLE_SZ];
};

int main(int argc, char **argv)
{
struct handle h = {{8, 1 }, { 12, }};

open_by_handle_at(AT_FDCWD, &h.fh, O_RDONLY);
return 0;
}

Google-Bug-Id: 120690101
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Cc: stable@kernel.org

show more ...

ext4: include terminating u32 in size of xattr entries when expanding inodes

In ext4_expand_extra_isize_ea(), we calculate the total size of the
xattr header, plus the xattr entries so we know how m

ext4: include terminating u32 in size of xattr entries when expanding inodes

In ext4_expand_extra_isize_ea(), we calculate the total size of the
xattr header, plus the xattr entries so we know how much of the
beginning part of the xattrs to move when expanding the inode extra
size. We need to include the terminating u32 at the end of the xattr
entries, or else if there is uninitialized, non-zero bytes after the
xattr entries and before the xattr values, the list of xattr entries
won't be properly terminated.

Reported-by: Steve Graham <stgraham2000@gmail.com>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Cc: stable@kernel.org

show more ...

ext4: add ext4_sb_bread() to disambiguate ENOMEM cases

Today, when sb_bread() returns NULL, this can either be because of an
I/O error or because the system failed to allocate the buffer. Since
it'

ext4: add ext4_sb_bread() to disambiguate ENOMEM cases

Today, when sb_bread() returns NULL, this can either be because of an
I/O error or because the system failed to allocate the buffer. Since
it's an old interface, changing would require changing many call
sites.

So instead we create our own ext4_sb_bread(), which also allows us to
set the REQ_META flag.

Also fixed a problem in the xattr code where a NULL return in a
function could also mean that the xattr was not found, which could
lead to the wrong error getting returned to userspace.

Fixes: ac27a0ec112a ("ext4: initial copy of files from ext3")
Cc: stable@kernel.org # 2.6.19
Signed-off-by: Theodore Ts'o <tytso@mit.edu>

show more ...

ext4: missing !bh check in ext4_xattr_inode_write()

According to Ted Ts'o ext4_getblk() called in ext4_xattr_inode_write()
should not return bh = NULL

The only time that bh could be NULL, then, wou

ext4: missing !bh check in ext4_xattr_inode_write()

According to Ted Ts'o ext4_getblk() called in ext4_xattr_inode_write()
should not return bh = NULL

The only time that bh could be NULL, then, would be in the case of
something really going wrong; a programming error elsewhere (perhaps a
wild pointer dereference) or I/O error causing on-disk file system
corruption (although that would be highly unlikely given that we had
*just* allocated the blocks and so the metadata blocks in question
probably would still be in the cache).

Fixes: e50e5129f384 ("ext4: xattr-in-inode support")
Signed-off-by: Vasily Averin <vvs@virtuozzo.com>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Cc: stable@kernel.org # 4.13

show more ...

ext4: fix buffer leak in ext4_expand_extra_isize_ea() on error path

Fixes: de05ca852679 ("ext4: move call to ext4_error() into ...")
Signed-off-by: Vasily Averin <vvs@virtuozzo.com>
Signed-off-by: T

ext4: fix buffer leak in ext4_expand_extra_isize_ea() on error path

Fixes: de05ca852679 ("ext4: move call to ext4_error() into ...")
Signed-off-by: Vasily Averin <vvs@virtuozzo.com>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Cc: stable@kernel.org # 4.17

show more ...

ext4: fix buffer leak in ext4_xattr_move_to_block() on error path

Fixes: 3f2571c1f91f ("ext4: factor out xattr moving")
Fixes: 6dd4ee7cab7e ("ext4: Expand extra_inodes space per ...")
Reviewed-by: J

ext4: fix buffer leak in ext4_xattr_move_to_block() on error path

Fixes: 3f2571c1f91f ("ext4: factor out xattr moving")
Fixes: 6dd4ee7cab7e ("ext4: Expand extra_inodes space per ...")
Reviewed-by: Jan Kara <jack@suse.cz>
Signed-off-by: Vasily Averin <vvs@virtuozzo.com>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Cc: stable@kernel.org # 2.6.23

show more ...

ext4: release bs.bh before re-using in ext4_xattr_block_find()

bs.bh was taken in previous ext4_xattr_block_find() call,
it should be released before re-using

Fixes: 7e01c8e5420b ("ext3/4: fix unin

ext4: release bs.bh before re-using in ext4_xattr_block_find()

bs.bh was taken in previous ext4_xattr_block_find() call,
it should be released before re-using

Fixes: 7e01c8e5420b ("ext3/4: fix uninitialized bs in ...")
Signed-off-by: Vasily Averin <vvs@virtuozzo.com>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Cc: stable@kernel.org # 2.6.26

show more ...

ext4: fix buffer leak in ext4_xattr_get_block() on error path

Fixes: dec214d00e0d ("ext4: xattr inode deduplication")
Signed-off-by: Vasily Averin <vvs@virtuozzo.com>
Signed-off-by: Theodore Ts'o <t

ext4: fix buffer leak in ext4_xattr_get_block() on error path

Fixes: dec214d00e0d ("ext4: xattr inode deduplication")
Signed-off-by: Vasily Averin <vvs@virtuozzo.com>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Cc: stable@kernel.org # 4.13

show more ...

ext4: remove unneeded brelse call in ext4_xattr_inode_update_ref()

Signed-off-by: Vasily Averin <vvs@virtuozzo.com>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>

ext4: check for NUL characters in extended attribute's name

Extended attribute names are defined to be NUL-terminated, so the name
must not contain a NUL character. This is important because there

ext4: check for NUL characters in extended attribute's name

Extended attribute names are defined to be NUL-terminated, so the name
must not contain a NUL character. This is important because there are
places when remove extended attribute, the code uses strlen to
determine the length of the entry. That should probably be fixed at
some point, but code is currently really messy, so the simplest fix
for now is to simply validate that the extended attributes are sane.

https://bugzilla.kernel.org/show_bug.cgi?id=200401

Reported-by: Wen Xu <wen.xu@gatech.edu>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Cc: stable@vger.kernel.org

show more ...

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

Use a separate journal transaction if it turns out that we need to
convert an inline file to use an data block. Otherwise

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

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 <tytso@mit.edu>
Cc: stable@kernel.org

show more ...