linux-stable.git/fs/ext4/ialloc.c, branch v4.9.321

ext4: fix avefreec in find_group_orlov

2021-07-20T14:20:57+00:00

commit c89849cc0259f3d33624cc3bd127685c3c0fa25d upstream.

The avefreec should be average free clusters instead
of average free blocks, otherwize Orlov's allocator
will not work properly when bigalloc enabled.

Cc: stable@kernel.org
Signed-off-by: Pan Dong 
Link: https://lore.kernel.org/r/20210525073656.31594-1-pandong.peter@bytedance.com
Signed-off-by: Theodore Ts'o 
Signed-off-by: Greg Kroah-Hartman

ext4: fix check to prevent false positive report of incorrect used inodes

2021-05-22T08:40:19+00:00

commit a149d2a5cabbf6507a7832a1c4fd2593c55fd450 upstream.

Commit <50122847007> ("ext4: fix check to prevent initializing reserved
inodes") check the block group zero and prevent initializing reserved
inodes. But in some special cases, the reserved inode may not all belong
to the group zero, it may exist into the second group if we format
filesystem below.

  mkfs.ext4 -b 4096 -g 8192 -N 1024 -I 4096 /dev/sda

So, it will end up triggering a false positive report of a corrupted
file system. This patch fix it by avoid check reserved inodes if no free
inode blocks will be zeroed.

Cc: stable@kernel.org
Fixes: 50122847007 ("ext4: fix check to prevent initializing reserved inodes")
Signed-off-by: Zhang Yi 
Suggested-by: Jan Kara 
Link: https://lore.kernel.org/r/20210331121516.2243099-1-yi.zhang@huawei.com
Signed-off-by: Theodore Ts'o 
Signed-off-by: Greg Kroah-Hartman

ext4: avoid declaring fs inconsistent due to invalid file handles

2020-05-02T15:23:18+00:00

commit 8a363970d1dc38c4ec4ad575c862f776f468d057 upstream.

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 

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 
Cc: stable@kernel.org
Signed-off-by: Ashwin H 
Signed-off-by: Greg Kroah-Hartman

ext4: fix potential race between s_flex_groups online resizing and access

2020-03-11T06:53:01+00:00

commit 7c990728b99ed6fbe9c75fc202fce1172d9916da upstream.

During an online resize an array of s_flex_groups structures gets replaced
so it can get enlarged. If there is a concurrent access to the array and
this memory has been reused then this can lead to an invalid memory access.

The s_flex_group array has been converted into an array of pointers rather
than an array of structures. This is to ensure that the information
contained in the structures cannot get out of sync during a resize due to
an accessor updating the value in the old structure after it has been
copied but before the array pointer is updated. Since the structures them-
selves are no longer copied but only the pointers to them this case is
mitigated.

Link: https://bugzilla.kernel.org/show_bug.cgi?id=206443
Link: https://lore.kernel.org/r/20200221053458.730016-4-tytso@mit.edu
Signed-off-by: Suraj Jitindar Singh 
Signed-off-by: Theodore Ts'o 
Cc: stable@kernel.org # 4.4.x
Cc: stable@kernel.org # 4.9.x
Signed-off-by: Sasha Levin

ext4: fix check to prevent initializing reserved inodes

2018-08-15T16:14:41+00:00

commit 5012284700775a4e6e3fbe7eac4c543c4874b559 upstream.

Commit 8844618d8aa7: "ext4: only look at the bg_flags field if it is
valid" will complain if block group zero does not have the
EXT4_BG_INODE_ZEROED flag set.  Unfortunately, this is not correct,
since a freshly created file system has this flag cleared.  It gets
almost immediately after the file system is mounted read-write --- but
the following somewhat unlikely sequence will end up triggering a
false positive report of a corrupted file system:

   mkfs.ext4 /dev/vdc
   mount -o ro /dev/vdc /vdc
   mount -o remount,rw /dev/vdc

Instead, when initializing the inode table for block group zero, test
to make sure that itable_unused count is not too large, since that is
the case that will result in some or all of the reserved inodes
getting cleared.

This fixes the failures reported by Eric Whiteney when running
generic/230 and generic/231 in the the nojournal test case.

Fixes: 8844618d8aa7 ("ext4: only look at the bg_flags field if it is valid")
Reported-by: Eric Whitney 
Signed-off-by: Theodore Ts'o 
Signed-off-by: Greg Kroah-Hartman

ext4: check for allocation block validity with block group locked

2018-08-03T05:55:26+00:00

commit 8d5a803c6a6ce4ec258e31f76059ea5153ba46ef upstream.

With commit 044e6e3d74a3: "ext4: don't update checksum of new
initialized bitmaps" the buffer valid bit will get set without
actually setting up the checksum for the allocation bitmap, since the
checksum will get calculated once we actually allocate an inode or
block.

If we are doing this, then we need to (re-)check the verified bit
after we take the block group lock.  Otherwise, we could race with
another process reading and verifying the bitmap, which would then
complain about the checksum being invalid.

https://bugs.launchpad.net/ubuntu/+source/linux/+bug/1780137

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

ext4: only look at the bg_flags field if it is valid

2018-07-11T14:26:44+00:00

commit 8844618d8aa7a9973e7b527d038a2a589665002c upstream.

The bg_flags field in the block group descripts is only valid if the
uninit_bg or metadata_csum feature is enabled.  We were not
consistently looking at this field; fix this.

Also block group #0 must never have uninitialized allocation bitmaps,
or need to be zeroed, since that's where the root inode, and other
special inodes are set up.  Check for these conditions and mark the
file system as corrupted if they are detected.

This addresses CVE-2018-10876.

https://bugzilla.kernel.org/show_bug.cgi?id=199403

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

ext4: add validity checks for bitmap block numbers

2018-05-01T22:13:03+00:00

commit 7dac4a1726a9c64a517d595c40e95e2d0d135f6f upstream.

An privileged attacker can cause a crash by mounting a crafted ext4
image which triggers a out-of-bounds read in the function
ext4_valid_block_bitmap() in fs/ext4/balloc.c.

This issue has been assigned CVE-2018-1093.

BugLink: https://bugzilla.kernel.org/show_bug.cgi?id=199181
BugLink: https://bugzilla.redhat.com/show_bug.cgi?id=1560782
Reported-by: Wen Xu 
Signed-off-by: Theodore Ts'o 
Cc: stable@vger.kernel.org
Signed-off-by: Greg Kroah-Hartman

ext4: don't update checksum of new initialized bitmaps

2018-04-24T07:34:12+00:00

commit 044e6e3d74a3d7103a0c8a9305dfd94d64000660 upstream.

When reading the inode or block allocation bitmap, if the bitmap needs
to be initialized, do not update the checksum in the block group
descriptor.  That's because we're not set up to journal those changes.
Instead, just set the verified bit on the bitmap block, so that it's
not necessary to validate the checksum.

When a block or inode allocation actually happens, at that point the
checksum will be calculated, and update of the bg descriptor block
will be properly journalled.

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

fscrypt: use ENOKEY when file cannot be created w/o key

2017-11-30T08:39:11+00:00

[ Upstream commit 54475f531bb8d7078f63c159e5e0615d486c498c ]

As part of an effort to clean up fscrypt-related error codes, make
attempting to create a file in an encrypted directory that hasn't been
"unlocked" fail with ENOKEY.  Previously, several error codes were used
for this case, including ENOENT, EACCES, and EPERM, and they were not
consistent between and within filesystems.  ENOKEY is a better choice
because it expresses that the failure is due to lacking the encryption
key.  It also matches the error code returned when trying to open an
encrypted regular file without the key.

I am not aware of any users who might be relying on the previous
inconsistent error codes, which were never documented anywhere.

This failure case will be exercised by an xfstest.

Signed-off-by: Eric Biggers 
Signed-off-by: Theodore Ts'o 
Signed-off-by: Sasha Levin 
Signed-off-by: Greg Kroah-Hartman