linux-stable.git/fs/ext4/resize.c, branch linux-4.9.y

ext4: continue to expand file system when the target size doesn't reach

2022-10-26T11:15:48+00:00

commit df3cb754d13d2cd5490db9b8d536311f8413a92e upstream.

When expanding a file system from (16TiB-2MiB) to 18TiB, the operation
exits early which leads to result inconsistency between resize2fs and
Ext4 kernel driver.

=== before ===
○ → resize2fs /dev/mapper/thin
resize2fs 1.45.5 (07-Jan-2020)
Filesystem at /dev/mapper/thin is mounted on /mnt/test; on-line resizing required
old_desc_blocks = 2048, new_desc_blocks = 2304
The filesystem on /dev/mapper/thin is now 4831837696 (4k) blocks long.

[  865.186308] EXT4-fs (dm-5): mounted filesystem with ordered data mode. Opts: (null). Quota mode: none.
[  912.091502] dm-4: detected capacity change from 34359738368 to 38654705664
[  970.030550] dm-5: detected capacity change from 34359734272 to 38654701568
[ 1000.012751] EXT4-fs (dm-5): resizing filesystem from 4294966784 to 4831837696 blocks
[ 1000.012878] EXT4-fs (dm-5): resized filesystem to 4294967296

=== after ===
[  129.104898] EXT4-fs (dm-5): mounted filesystem with ordered data mode. Opts: (null). Quota mode: none.
[  143.773630] dm-4: detected capacity change from 34359738368 to 38654705664
[  198.203246] dm-5: detected capacity change from 34359734272 to 38654701568
[  207.918603] EXT4-fs (dm-5): resizing filesystem from 4294966784 to 4831837696 blocks
[  207.918754] EXT4-fs (dm-5): resizing filesystem from 4294967296 to 4831837696 blocks
[  207.918758] EXT4-fs (dm-5): Converting file system to meta_bg
[  207.918790] EXT4-fs (dm-5): resizing filesystem from 4294967296 to 4831837696 blocks
[  221.454050] EXT4-fs (dm-5): resized to 4658298880 blocks
[  227.634613] EXT4-fs (dm-5): resized filesystem to 4831837696

Signed-off-by: Jerry Lee 
Link: https://lore.kernel.org/r/PU1PR04MB22635E739BD21150DC182AC6A18C9@PU1PR04MB2263.apcprd04.prod.outlook.com
Signed-off-by: Theodore Ts'o 
Signed-off-by: Greg Kroah-Hartman

ext4: avoid resizing to a partial cluster size

2022-08-25T09:09:31+00:00

[ Upstream commit 69cb8e9d8cd97cdf5e293b26d70a9dee3e35e6bd ]

This patch avoids an attempt to resize the filesystem to an
unaligned cluster boundary.  An online resize to a size that is not
integral to cluster size results in the last iteration attempting to
grow the fs by a negative amount, which trips a BUG_ON and leaves the fs
with a corrupted in-memory superblock.

Signed-off-by: Oleg Kiselev 
Link: https://lore.kernel.org/r/0E92A0AB-4F16-4F1A-94B7-702CC6504FDE@amazon.com
Signed-off-by: Theodore Ts'o 
Signed-off-by: Sasha Levin

ext4: update s_overhead_clusters in the superblock during an on-line resize

2022-08-25T09:09:26+00:00

commit de394a86658ffe4e89e5328fd4993abfe41b7435 upstream.

When doing an online resize, the on-disk superblock on-disk wasn't
updated.  This means that when the file system is unmounted and
remounted, and the on-disk overhead value is non-zero, this would
result in the results of statfs(2) to be incorrect.

This was partially fixed by Commits 10b01ee92df5 ("ext4: fix overhead
calculation to account for the reserved gdt blocks"), 85d825dbf489
("ext4: force overhead calculation if the s_overhead_cluster makes no
sense"), and eb7054212eac ("ext4: update the cached overhead value in
the superblock").

However, since it was too expensive to forcibly recalculate the
overhead for bigalloc file systems at every mount, this didn't fix the
problem for bigalloc file systems.  This commit should address the
problem when resizing file systems with the bigalloc feature enabled.

Signed-off-by: Theodore Ts'o 
Cc: stable@kernel.org
Reviewed-by: Andreas Dilger 
Link: https://lore.kernel.org/r/20220629040026.112371-1-tytso@mit.edu
Signed-off-by: Theodore Ts'o 
Signed-off-by: Greg Kroah-Hartman

ext4: add reserved GDT blocks check

2022-06-25T09:45:18+00:00

commit b55c3cd102a6f48b90e61c44f7f3dda8c290c694 upstream.

We capture a NULL pointer issue when resizing a corrupt ext4 image which
is freshly clear resize_inode feature (not run e2fsck). It could be
simply reproduced by following steps. The problem is because of the
resize_inode feature was cleared, and it will convert the filesystem to
meta_bg mode in ext4_resize_fs(), but the es->s_reserved_gdt_blocks was
not reduced to zero, so could we mistakenly call reserve_backup_gdb()
and passing an uninitialized resize_inode to it when adding new group
descriptors.

 mkfs.ext4 /dev/sda 3G
 tune2fs -O ^resize_inode /dev/sda #forget to run requested e2fsck
 mount /dev/sda /mnt
 resize2fs /dev/sda 8G

 ========
 BUG: kernel NULL pointer dereference, address: 0000000000000028
 CPU: 19 PID: 3243 Comm: resize2fs Not tainted 5.18.0-rc7-00001-gfde086c5ebfd #748
 ...
 RIP: 0010:ext4_flex_group_add+0xe08/0x2570
 ...
 Call Trace:
  
  ext4_resize_fs+0xbec/0x1660
  __ext4_ioctl+0x1749/0x24e0
  ext4_ioctl+0x12/0x20
  __x64_sys_ioctl+0xa6/0x110
  do_syscall_64+0x3b/0x90
  entry_SYSCALL_64_after_hwframe+0x44/0xae
 RIP: 0033:0x7f2dd739617b
 ========

The fix is simple, add a check in ext4_resize_begin() to make sure that
the es->s_reserved_gdt_blocks is zero when the resize_inode feature is
disabled.

Cc: stable@kernel.org
Signed-off-by: Zhang Yi 
Reviewed-by: Ritesh Harjani 
Reviewed-by: Jan Kara 
Link: https://lore.kernel.org/r/20220601092717.763694-1-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 potential race between online resizing and write operations

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

commit 1d0c3924a92e69bfa91163bda83c12a994b4d106 upstream.

During an online resize an array of pointers to buffer heads gets
replaced so it can get enlarged.  If there is a racing block
allocation or deallocation which uses the old array, and the old array
has gotten reused this can lead to a GPF or some other random kernel
memory getting modified.

Link: https://bugzilla.kernel.org/show_bug.cgi?id=206443
Link: https://lore.kernel.org/r/20200221053458.730016-2-tytso@mit.edu
Reported-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: report real fs size after failed resize

2019-04-20T07:07:46+00:00

[ Upstream commit 6c7328400e0488f7d49e19e02290ba343b6811b2 ]

Currently when the file system resize using ext4_resize_fs() fails it
will report into log that "resized filesystem to ".  However this may not be true in the case of failure.  Use the
current block count as returned by ext4_blocks_count() to report the
block count.

Additionally, report a warning that "error occurred during file system
resize"

Signed-off-by: Lukas Czerner 
Signed-off-by: Theodore Ts'o 
Signed-off-by: Sasha Levin

ext4: add missing brelse() in add_new_gdb_meta_bg()

2019-04-20T07:07:46+00:00

[ Upstream commit d64264d6218e6892edd832dc3a5a5857c2856c53 ]

Currently in add_new_gdb_meta_bg() there is a missing brelse of gdb_bh
in case ext4_journal_get_write_access() fails.
Additionally kvfree() is missing in the same error path. Fix it by
moving the ext4_journal_get_write_access() before the ext4 sb update as
Ted suggested and release n_group_desc and gdb_bh in case it fails.

Fixes: 61a9c11e5e7a ("ext4: add missing brelse() add_new_gdb_meta_bg()'s error path")
Signed-off-by: Lukas Czerner 
Signed-off-by: Theodore Ts'o 
Signed-off-by: Sasha Levin

ext4: fix crash during online resizing

2019-03-23T12:19:48+00:00

commit f96c3ac8dfc24b4e38fc4c2eba5fea2107b929d1 upstream.

When computing maximum size of filesystem possible with given number of
group descriptor blocks, we forget to include s_first_data_block into
the number of blocks. Thus for filesystems with non-zero
s_first_data_block it can happen that computed maximum filesystem size
is actually lower than current filesystem size which confuses the code
and eventually leads to a BUG_ON in ext4_alloc_group_tables() hitting on
flex_gd->count == 0. The problem can be reproduced like:

truncate -s 100g /tmp/image
mkfs.ext4 -b 1024 -E resize=262144 /tmp/image 32768
mount -t ext4 -o loop /tmp/image /mnt
resize2fs /dev/loop0 262145
resize2fs /dev/loop0 300000

Fix the problem by properly including s_first_data_block into the
computed number of filesystem blocks.

Fixes: 1c6bd7173d66 "ext4: convert file system to meta_bg if needed..."
Signed-off-by: Jan Kara 
Signed-off-by: Theodore Ts'o 
Cc: stable@vger.kernel.org
Signed-off-by: Greg Kroah-Hartman