[ Upstream commit 377254b2cd2252c7c3151b113cbdf93a7736c2e9 ]
If a device is hot-removed --- for example, when a physical device is
unplugged from pcie slot or a nbd device's network is shutdown ---
this can result in a BUG_ON() crash in submit_bh_wbc(). This is
because the when the block device dies, the buffer heads will have
their Buffer_Mapped flag get cleared, leading to the crash in
submit_bh_wbc.
We had attempted to work around this problem in commit a17712c8
("ext4: check superblock mapped prior to committing"). Unfortunately,
it's still possible to hit the BUG_ON(!buffer_mapped(bh)) if the
device dies between when the work-around check in ext4_commit_super()
and when submit_bh_wbh() is finally called:
Code path:
ext4_commit_super
judge if 'buffer_mapped(sbh)' is false, return <== commit a17712c8
lock_buffer(sbh)
...
unlock_buffer(sbh)
__sync_dirty_buffer(sbh,...
lock_buffer(sbh)
judge if 'buffer_mapped(sbh))' is false, return <== added by this patch
submit_bh(...,sbh)
submit_bh_wbc(...,sbh,...)
[100722.966497] kernel BUG at fs/buffer.c:3095! <== BUG_ON(!buffer_mapped(bh))' in submit_bh_wbc()
[100722.966503] invalid opcode: 0000 [#1] SMP
[100722.966566] task: ffff8817e15a9e40 task.stack: ffffc90024744000
[100722.966574] RIP: 0010:submit_bh_wbc+0x180/0x190
[100722.966575] RSP: 0018:ffffc90024747a90 EFLAGS: 00010246
[100722.966576] RAX: 0000000000620005 RBX: ffff8818a80603a8 RCX: 0000000000000000
[100722.966576] RDX: ffff8818a80603a8 RSI: 0000000000020800 RDI: 0000000000000001
[100722.966577] RBP: ffffc90024747ac0 R08: 0000000000000000 R09: ffff88207f94170d
[100722.966578] R10: 00000000000437c8 R11: 0000000000000001 R12: 0000000000020800
[100722.966578] R13: 0000000000000001 R14: 000000000bf9a438 R15: ffff88195f333000
[100722.966580] FS: 00007fa2eee27700(0000) GS:ffff88203d840000(0000) knlGS:0000000000000000
[100722.966580] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[100722.966581] CR2: 0000000000f0b008 CR3: 000000201a622003 CR4: 00000000007606e0
[100722.966582] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
[100722.966583] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
[100722.966583] PKRU: 55555554
[100722.966583] Call Trace:
[100722.966588] __sync_dirty_buffer+0x6e/0xd0
[100722.966614] ext4_commit_super+0x1d8/0x290 [ext4]
[100722.966626] __ext4_std_error+0x78/0x100 [ext4]
[100722.966635] ? __ext4_journal_get_write_access+0xca/0x120 [ext4]
[100722.966646] ext4_reserve_inode_write+0x58/0xb0 [ext4]
[100722.966655] ? ext4_dirty_inode+0x48/0x70 [ext4]
[100722.966663] ext4_mark_inode_dirty+0x53/0x1e0 [ext4]
[100722.966671] ? __ext4_journal_start_sb+0x6d/0xf0 [ext4]
[100722.966679] ext4_dirty_inode+0x48/0x70 [ext4]
[100722.966682] __mark_inode_dirty+0x17f/0x350
[100722.966686] generic_update_time+0x87/0xd0
[100722.966687] touch_atime+0xa9/0xd0
[100722.966690] generic_file_read_iter+0xa09/0xcd0
[100722.966694] ? page_cache_tree_insert+0xb0/0xb0
[100722.966704] ext4_file_read_iter+0x4a/0x100 [ext4]
[100722.966707] ? __inode_security_revalidate+0x4f/0x60
[100722.966709] __vfs_read+0xec/0x160
[100722.966711] vfs_read+0x8c/0x130
[100722.966712] SyS_pread64+0x87/0xb0
[100722.966716] do_syscall_64+0x67/0x1b0
[100722.966719] entry_SYSCALL64_slow_path+0x25/0x25
To address this, add the check of 'buffer_mapped(bh)' to
__sync_dirty_buffer(). This also has the benefit of fixing this for
other file systems.
With this addition, we can drop the workaround in ext4_commit_supper().
[ Commit description rewritten by tytso. ]
Signed-off-by: Xianting Tian <xianting_tian@126.com>
Link: https://lore.kernel.org/r/1596211825-8750-1-git-send-email-xianting_tian@126.com
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit 0f5bde1db174f6c471f0bd27198575719dabe3e5 ] When remounting filesystem fails late during remount handling and block_validity mount option is also changed during the remount, we fail to restore system zone information to a state matching the mount option. This is mostly harmless, just the block validity checking will not match the situation described by the mount option. Make sure these two are always consistent. Reported-by: Lukas Czerner <lczerner@redhat.com> Reviewed-by: Lukas Czerner <lczerner@redhat.com> Signed-off-by: Jan Kara <jack@suse.cz> Link: https://lore.kernel.org/r/20200728130437.7804-7-jack@suse.cz Signed-off-by: Theodore Ts'o <tytso@mit.edu> Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit d176b1f62f242ab259ff665a26fbac69db1aecba ] ext4_setup_system_zone() can fail. Handle the failure in ext4_remount(). Reviewed-by: Lukas Czerner <lczerner@redhat.com> Signed-off-by: Jan Kara <jack@suse.cz> Link: https://lore.kernel.org/r/20200728130437.7804-2-jack@suse.cz Signed-off-by: Theodore Ts'o <tytso@mit.edu> Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit f25391ebb475d3ffb3aa61bb90e3594c841749ef ] Currently there is a problem with mount options that can be both set by vfs using mount flags or by a string parsing in ext4. i_version/iversion options gets lost after remount, for example $ mount -o i_version /dev/pmem0 /mnt $ grep pmem0 /proc/self/mountinfo | grep i_version 310 95 259:0 / /mnt rw,relatime shared:163 - ext4 /dev/pmem0 rw,seclabel,i_version $ mount -o remount,ro /mnt $ grep pmem0 /proc/self/mountinfo | grep i_version nolazytime gets ignored by ext4 on remount, for example $ mount -o lazytime /dev/pmem0 /mnt $ grep pmem0 /proc/self/mountinfo | grep lazytime 310 95 259:0 / /mnt rw,relatime shared:163 - ext4 /dev/pmem0 rw,lazytime,seclabel $ mount -o remount,nolazytime /mnt $ grep pmem0 /proc/self/mountinfo | grep lazytime 310 95 259:0 / /mnt rw,relatime shared:163 - ext4 /dev/pmem0 rw,lazytime,seclabel Fix it by applying the SB_LAZYTIME and SB_I_VERSION flags from *flags to s_flags before we parse the option and use the resulting state of the same flags in *flags at the end of successful remount. Signed-off-by: Lukas Czerner <lczerner@redhat.com> Reviewed-by: Ritesh Harjani <riteshh@linux.ibm.com> Link: https://lore.kernel.org/r/20200723150526.19931-1-lczerner@redhat.com Signed-off-by: Theodore Ts'o <tytso@mit.edu> Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit 273108fa5015eeffc4bacfa5ce272af3434b96e4 ] Ext4 uses blkdev_get_by_dev() to get the block_device for journal device which does check to see if the read-only block device was opened read-only. As a result ext4 will hapily proceed mounting the file system with external journal on read-only device. This is bad as we would not be able to use the journal leading to errors later on. Instead of simply failing to mount file system in this case, treat it in a similar way we treat internal journal on read-only device. Allow to mount with -o noload in read-only mode. This can be reproduced easily like this: mke2fs -F -O journal_dev $JOURNAL_DEV 100M mkfs.$FSTYPE -F -J device=$JOURNAL_DEV $FS_DEV blockdev --setro $JOURNAL_DEV mount $FS_DEV $MNT touch $MNT/file umount $MNT leading to error like this [ 1307.318713] ------------[ cut here ]------------ [ 1307.323362] generic_make_request: Trying to write to read-only block-device dm-2 (partno 0) [ 1307.331741] WARNING: CPU: 36 PID: 3224 at block/blk-core.c:855 generic_make_request_checks+0x2c3/0x580 [ 1307.341041] Modules linked in: ext4 mbcache jbd2 rfkill intel_rapl_msr intel_rapl_common isst_if_commd [ 1307.419445] CPU: 36 PID: 3224 Comm: jbd2/dm-2 Tainted: G W I 5.8.0-rc5 #2 [ 1307.427359] Hardware name: Dell Inc. PowerEdge R740/01KPX8, BIOS 2.3.10 08/15/2019 [ 1307.434932] RIP: 0010:generic_make_request_checks+0x2c3/0x580 [ 1307.440676] Code: 94 03 00 00 48 89 df 48 8d 74 24 08 c6 05 cf 2b 18 01 01 e8 7f a4 ff ff 48 c7 c7 50e [ 1307.459420] RSP: 0018:ffffc0d70eb5fb48 EFLAGS: 00010286 [ 1307.464646] RAX: 0000000000000000 RBX: ffff9b33b2978300 RCX: 0000000000000000 [ 1307.471780] RDX: ffff9b33e12a81e0 RSI: ffff9b33e1298000 RDI: ffff9b33e1298000 [ 1307.478913] RBP: ffff9b7b9679e0c0 R08: 0000000000000837 R09: 0000000000000024 [ 1307.486044] R10: 0000000000000000 R11: ffffc0d70eb5f9f0 R12: 0000000000000400 [ 1307.493177] R13: 0000000000000000 R14: 0000000000000001 R15: 0000000000000000 [ 1307.500308] FS: 0000000000000000(0000) GS:ffff9b33e1280000(0000) knlGS:0000000000000000 [ 1307.508396] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [ 1307.514142] CR2: 000055eaf4109000 CR3: 0000003dee40a006 CR4: 00000000007606e0 [ 1307.521273] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 [ 1307.528407] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 [ 1307.535538] PKRU: 55555554 [ 1307.538250] Call Trace: [ 1307.540708] generic_make_request+0x30/0x340 [ 1307.544985] submit_bio+0x43/0x190 [ 1307.548393] ? bio_add_page+0x62/0x90 [ 1307.552068] submit_bh_wbc+0x16a/0x190 [ 1307.555833] jbd2_write_superblock+0xec/0x200 [jbd2] [ 1307.560803] jbd2_journal_update_sb_log_tail+0x65/0xc0 [jbd2] [ 1307.566557] jbd2_journal_commit_transaction+0x2ae/0x1860 [jbd2] [ 1307.572566] ? check_preempt_curr+0x7a/0x90 [ 1307.576756] ? update_curr+0xe1/0x1d0 [ 1307.580421] ? account_entity_dequeue+0x7b/0xb0 [ 1307.584955] ? newidle_balance+0x231/0x3d0 [ 1307.589056] ? __switch_to_asm+0x42/0x70 [ 1307.592986] ? __switch_to_asm+0x36/0x70 [ 1307.596918] ? lock_timer_base+0x67/0x80 [ 1307.600851] kjournald2+0xbd/0x270 [jbd2] [ 1307.604873] ? finish_wait+0x80/0x80 [ 1307.608460] ? commit_timeout+0x10/0x10 [jbd2] [ 1307.612915] kthread+0x114/0x130 [ 1307.616152] ? kthread_park+0x80/0x80 [ 1307.619816] ret_from_fork+0x22/0x30 [ 1307.623400] ---[ end trace 27490236265b1630 ]--- Signed-off-by: Lukas Czerner <lczerner@redhat.com> Reviewed-by: Andreas Dilger <adilger@dilger.ca> Link: https://lore.kernel.org/r/20200717090605.2612-1-lczerner@redhat.com Signed-off-by: Theodore Ts'o <tytso@mit.edu> Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit 11215630aada28307ba555a43138db6ac54fa825 ] A customer has reported a BUG_ON in ext4_clear_journal_err() hitting during an LTP testing. Either this has been caused by a test setup issue where the filesystem was being overwritten while LTP was mounting it or the journal replay has overwritten the superblock with invalid data. In either case it is preferable we don't take the machine down with a BUG_ON. So handle the situation of unexpectedly missing has_journal feature more gracefully. We issue warning and fail the mount in the cases where the race window is narrow and the failed check is most likely a programming error. In cases where fs corruption is more likely, we do full ext4_error() handling before failing mount / remount. Reviewed-by: Lukas Czerner <lczerner@redhat.com> Signed-off-by: Jan Kara <jack@suse.cz> Link: https://lore.kernel.org/r/20200710140759.18031-1-jack@suse.cz Signed-off-by: Theodore Ts'o <tytso@mit.edu> Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit bf9a379d0980e7413d94cb18dac73db2bfc5f470 ] Currently, add_system_zone() just silently merges two added system zones that overlap. However the overlap should not happen and it generally suggests that some unrelated metadata overlap which indicates the fs is corrupted. We should have caught such problems earlier (e.g. in ext4_check_descriptors()) but add this check as another line of defense. In later patch we also use this for stricter checking of journal inode extent tree. Reviewed-by: Lukas Czerner <lczerner@redhat.com> Signed-off-by: Jan Kara <jack@suse.cz> Link: https://lore.kernel.org/r/20200728130437.7804-3-jack@suse.cz Signed-off-by: Theodore Ts'o <tytso@mit.edu> Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit 5872331b3d91820e14716632ebb56b1399b34fe1 ]
If for any reason a directory passed to do_split() does not have enough
active entries to exceed half the size of the block, we can end up
iterating over all "count" entries without finding a split point.
In this case, count == move, and split will be zero, and we will
attempt a negative index into map[].
Guard against this by detecting this case, and falling back to
split-to-half-of-count instead; in this case we will still have
plenty of space (> half blocksize) in each split block.
Fixes: ef2b02d3e617 ("ext34: ensure do_split leaves enough free space in both blocks")
Signed-off-by: Eric Sandeen <sandeen@redhat.com>
Reviewed-by: Andreas Dilger <adilger@dilger.ca>
Reviewed-by: Jan Kara <jack@suse.cz>
Link: https://lore.kernel.org/r/f53e246b-647c-64bb-16ec-135383c70ad7@redhat.com
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Signed-off-by: Sasha Levin <sashal@kernel.org>
commit 7303cb5bfe845f7d43cd9b2dbd37dbb266efda9b upstream.
ext4_search_dir() and ext4_generic_delete_entry() can be called both for
standard director blocks and for inline directories stored inside inode
or inline xattr space. For the second case we didn't call
ext4_check_dir_entry() with proper constraints that could result in
accepting corrupted directory entry as well as false positive filesystem
errors like:
EXT4-fs error (device dm-0): ext4_search_dir:1395: inode #28320400:
block 113246792: comm dockerd: bad entry in directory: directory entry too
close to block end - offset=0, inode=28320403, rec_len=32, name_len=8,
size=4096
Fix the arguments passed to ext4_check_dir_entry().
Fixes: 109ba779d6cc ("ext4: check for directory entries too close to block end")
CC: stable@vger.kernel.org
Signed-off-by: Jan Kara <jack@suse.cz>
Link: https://lore.kernel.org/r/20200731162135.8080-1-jack@suse.cz
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This patch is used to fix ext4 direct I/O read error when
the read size is not aligned with block size.
Then, I will use a test to explain the error.
(1) Make a file that is not aligned with block size:
$dd if=/dev/zero of=./test.jar bs=1000 count=3
(2) I wrote a source file named "direct_io_read_file.c" as following:
#include <stdio.h>
#include <stdlib.h>
#include <unistd.h>
#include <sys/file.h>
#include <sys/types.h>
#include <sys/stat.h>
#include <string.h>
#define BUF_SIZE 1024
int main()
{
int fd;
int ret;
unsigned char *buf;
ret = posix_memalign((void **)&buf, 512, BUF_SIZE);
if (ret) {
perror("posix_memalign failed");
exit(1);
}
fd = open("./test.jar", O_RDONLY | O_DIRECT, 0755);
if (fd < 0){
perror("open ./test.jar failed");
exit(1);
}
do {
ret = read(fd, buf, BUF_SIZE);
printf("ret=%d\n",ret);
if (ret < 0) {
perror("write test.jar failed");
}
} while (ret > 0);
free(buf);
close(fd);
}
(3) Compile the source file:
$gcc direct_io_read_file.c -D_GNU_SOURCE
(4) Run the test program:
$./a.out
The result is as following:
ret=1024
ret=1024
ret=952
ret=-1
write test.jar failed: Invalid argument.
I have tested this program on XFS filesystem, XFS does not have
this problem, because XFS use iomap_dio_rw() to do direct I/O
read. And the comparing between read offset and file size is done
in iomap_dio_rw(), the code is as following:
if (pos < size) {
retval = filemap_write_and_wait_range(mapping, pos,
pos + iov_length(iov, nr_segs) - 1);
if (!retval) {
retval = mapping->a_ops->direct_IO(READ, iocb,
iov, pos, nr_segs);
}
...
}
...only when "pos < size", direct I/O can be done, or 0 will be return.
I have tested the fix patch on Ext4, it is up to the mustard of
EINVAL in man2(read) as following:
#include <unistd.h>
ssize_t read(int fd, void *buf, size_t count);
EINVAL
fd is attached to an object which is unsuitable for reading;
or the file was opened with the O_DIRECT flag, and either the
address specified in buf, the value specified in count, or the
current file offset is not suitably aligned.
So I think this patch can be applied to fix ext4 direct I/O error.
However Ext4 introduces direct I/O read using iomap infrastructure
on kernel 5.5, the patch is commit <b1b4705d54ab>
("ext4: introduce direct I/O read using iomap infrastructure"),
then Ext4 will be the same as XFS, they all use iomap_dio_rw() to do direct
I/O read. So this problem does not exist on kernel 5.5 for Ext4.
>From above description, we can see this problem exists on all the kernel
versions between kernel 3.14 and kernel 5.4. It will cause the Applications
to fail to read. For example, when the search service downloads a new full
index file, the search engine is loading the previous index file and is
processing the search request, it can not use buffer io that may squeeze
the previous index file in use from pagecache, so the serch service must
use direct I/O read.
Please apply this patch on these kernel versions, or please use the method
on kernel 5.5 to fix this problem.
Fixes: 9fe55eea7e4b ("Fix race when checking i_size on direct i/o read")
Reviewed-by: Jan Kara <jack@suse.cz>
Co-developed-by: Wang Long <wanglong19@meituan.com>
Signed-off-by: Wang Long <wanglong19@meituan.com>
Signed-off-by: Jiang Ying <jiangying8582@126.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>