OpenCloudOS-Kernel/fs/xfs/libxfs/xfs_inode_buf.c

707 lines
19 KiB
C
Raw Normal View History

// SPDX-License-Identifier: GPL-2.0
/*
* Copyright (c) 2000-2006 Silicon Graphics, Inc.
* All Rights Reserved.
*/
#include "xfs.h"
#include "xfs_fs.h"
#include "xfs_shared.h"
#include "xfs_format.h"
#include "xfs_log_format.h"
#include "xfs_trans_resv.h"
#include "xfs_mount.h"
#include "xfs_inode.h"
#include "xfs_errortag.h"
#include "xfs_error.h"
#include "xfs_icache.h"
#include "xfs_trans.h"
#include "xfs_ialloc.h"
#include "xfs_dir2.h"
#include <linux/iversion.h>
/*
* If we are doing readahead on an inode buffer, we might be in log recovery
* reading an inode allocation buffer that hasn't yet been replayed, and hence
* has not had the inode cores stamped into it. Hence for readahead, the buffer
* may be potentially invalid.
*
xfs: inode recovery readahead can race with inode buffer creation When we do inode readahead in log recovery, we do can do the readahead before we've replayed the icreate transaction that stamps the buffer with inode cores. The inode readahead verifier catches this and marks the buffer as !done to indicate that it doesn't yet contain valid inodes. In adding buffer error notification (i.e. setting b_error = -EIO at the same time as as we clear the done flag) to such a readahead verifier failure, we can then get subsequent inode recovery failing with this error: XFS (dm-0): metadata I/O error: block 0xa00060 ("xlog_recover_do..(read#2)") error 5 numblks 32 This occurs when readahead completion races with icreate item replay such as: inode readahead find buffer lock buffer submit RA io .... icreate recovery xfs_trans_get_buffer find buffer lock buffer <blocks on RA completion> ..... <ra completion> fails verifier clear XBF_DONE set bp->b_error = -EIO release and unlock buffer <icreate gains lock> icreate initialises buffer marks buffer as done adds buffer to delayed write queue releases buffer At this point, we have an initialised inode buffer that is up to date but has an -EIO state registered against it. When we finally get to recovering an inode in that buffer: inode item recovery xfs_trans_read_buffer find buffer lock buffer sees XBF_DONE is set, returns buffer sees bp->b_error is set fail log recovery! Essentially, we need xfs_trans_get_buf_map() to clear the error status of the buffer when doing a lookup. This function returns uninitialised buffers, so the buffer returned can not be in an error state and none of the code that uses this function expects b_error to be set on return. Indeed, there is an ASSERT(!bp->b_error); in the transaction case in xfs_trans_get_buf_map() that would have caught this if log recovery used transactions.... This patch firstly changes the inode readahead failure to set -EIO on the buffer, and secondly changes xfs_buf_get_map() to never return a buffer with an error state set so this first change doesn't cause unexpected log recovery failures. cc: <stable@vger.kernel.org> # 3.12 - current Signed-off-by: Dave Chinner <dchinner@redhat.com> Reviewed-by: Brian Foster <bfoster@redhat.com> Signed-off-by: Dave Chinner <david@fromorbit.com>
2016-01-12 04:03:44 +08:00
* If the readahead buffer is invalid, we need to mark it with an error and
* clear the DONE status of the buffer so that a followup read will re-read it
* from disk. We don't report the error otherwise to avoid warnings during log
* recovery and we don't get unnecessary panics on debug kernels. We use EIO here
xfs: inode recovery readahead can race with inode buffer creation When we do inode readahead in log recovery, we do can do the readahead before we've replayed the icreate transaction that stamps the buffer with inode cores. The inode readahead verifier catches this and marks the buffer as !done to indicate that it doesn't yet contain valid inodes. In adding buffer error notification (i.e. setting b_error = -EIO at the same time as as we clear the done flag) to such a readahead verifier failure, we can then get subsequent inode recovery failing with this error: XFS (dm-0): metadata I/O error: block 0xa00060 ("xlog_recover_do..(read#2)") error 5 numblks 32 This occurs when readahead completion races with icreate item replay such as: inode readahead find buffer lock buffer submit RA io .... icreate recovery xfs_trans_get_buffer find buffer lock buffer <blocks on RA completion> ..... <ra completion> fails verifier clear XBF_DONE set bp->b_error = -EIO release and unlock buffer <icreate gains lock> icreate initialises buffer marks buffer as done adds buffer to delayed write queue releases buffer At this point, we have an initialised inode buffer that is up to date but has an -EIO state registered against it. When we finally get to recovering an inode in that buffer: inode item recovery xfs_trans_read_buffer find buffer lock buffer sees XBF_DONE is set, returns buffer sees bp->b_error is set fail log recovery! Essentially, we need xfs_trans_get_buf_map() to clear the error status of the buffer when doing a lookup. This function returns uninitialised buffers, so the buffer returned can not be in an error state and none of the code that uses this function expects b_error to be set on return. Indeed, there is an ASSERT(!bp->b_error); in the transaction case in xfs_trans_get_buf_map() that would have caught this if log recovery used transactions.... This patch firstly changes the inode readahead failure to set -EIO on the buffer, and secondly changes xfs_buf_get_map() to never return a buffer with an error state set so this first change doesn't cause unexpected log recovery failures. cc: <stable@vger.kernel.org> # 3.12 - current Signed-off-by: Dave Chinner <dchinner@redhat.com> Reviewed-by: Brian Foster <bfoster@redhat.com> Signed-off-by: Dave Chinner <david@fromorbit.com>
2016-01-12 04:03:44 +08:00
* because all we want to do is say readahead failed; there is no-one to report
* the error to, so this will distinguish it from a non-ra verifier failure.
* Changes to this readahead error behaviour also need to be reflected in
xfs: handle dquot buffer readahead in log recovery correctly When we do dquot readahead in log recovery, we do not use a verifier as the underlying buffer may not have dquots in it. e.g. the allocation operation hasn't yet been replayed. Hence we do not want to fail recovery because we detect an operation to be replayed has not been run yet. This problem was addressed for inodes in commit d891400 ("xfs: inode buffers may not be valid during recovery readahead") but the problem was not recognised to exist for dquots and their buffers as the dquot readahead did not have a verifier. The result of not using a verifier is that when the buffer is then next read to replay a dquot modification, the dquot buffer verifier will only be attached to the buffer if *readahead is not complete*. Hence we can read the buffer, replay the dquot changes and then add it to the delwri submission list without it having a verifier attached to it. This then generates warnings in xfs_buf_ioapply(), which catches and warns about this case. Fix this and make it handle the same readahead verifier error cases as for inode buffers by adding a new readahead verifier that has a write operation as well as a read operation that marks the buffer as not done if any corruption is detected. Also make sure we don't run readahead if the dquot buffer has been marked as cancelled by recovery. This will result in readahead either succeeding and the buffer having a valid write verifier, or readahead failing and the buffer state requiring the subsequent read to resubmit the IO with the new verifier. In either case, this will result in the buffer always ending up with a valid write verifier on it. Note: we also need to fix the inode buffer readahead error handling to mark the buffer with EIO. Brian noticed the code I copied from there wrong during review, so fix it at the same time. Add comments linking the two functions that handle readahead verifier errors together so we don't forget this behavioural link in future. cc: <stable@vger.kernel.org> # 3.12 - current Signed-off-by: Dave Chinner <dchinner@redhat.com> Reviewed-by: Brian Foster <bfoster@redhat.com> Signed-off-by: Dave Chinner <david@fromorbit.com>
2016-01-12 04:04:01 +08:00
* xfs_dquot_buf_readahead_verify().
*/
static void
xfs_inode_buf_verify(
struct xfs_buf *bp,
bool readahead)
{
struct xfs_mount *mp = bp->b_mount;
xfs_agnumber_t agno;
int i;
int ni;
/*
* Validate the magic number and version of every inode in the buffer
*/
agno = xfs_daddr_to_agno(mp, XFS_BUF_ADDR(bp));
ni = XFS_BB_TO_FSB(mp, bp->b_length) * mp->m_sb.sb_inopblock;
for (i = 0; i < ni; i++) {
int di_ok;
xfs_dinode_t *dip;
xfs_agino_t unlinked_ino;
dip = xfs_buf_offset(bp, (i << mp->m_sb.sb_inodelog));
unlinked_ino = be32_to_cpu(dip->di_next_unlinked);
di_ok = xfs_verify_magic16(bp, dip->di_magic) &&
xfs_dinode_good_version(mp, dip->di_version) &&
xfs_verify_agino_or_null(mp, agno, unlinked_ino);
if (unlikely(XFS_TEST_ERROR(!di_ok, mp,
XFS_ERRTAG_ITOBP_INOTOBP))) {
if (readahead) {
bp->b_flags &= ~XBF_DONE;
xfs: inode recovery readahead can race with inode buffer creation When we do inode readahead in log recovery, we do can do the readahead before we've replayed the icreate transaction that stamps the buffer with inode cores. The inode readahead verifier catches this and marks the buffer as !done to indicate that it doesn't yet contain valid inodes. In adding buffer error notification (i.e. setting b_error = -EIO at the same time as as we clear the done flag) to such a readahead verifier failure, we can then get subsequent inode recovery failing with this error: XFS (dm-0): metadata I/O error: block 0xa00060 ("xlog_recover_do..(read#2)") error 5 numblks 32 This occurs when readahead completion races with icreate item replay such as: inode readahead find buffer lock buffer submit RA io .... icreate recovery xfs_trans_get_buffer find buffer lock buffer <blocks on RA completion> ..... <ra completion> fails verifier clear XBF_DONE set bp->b_error = -EIO release and unlock buffer <icreate gains lock> icreate initialises buffer marks buffer as done adds buffer to delayed write queue releases buffer At this point, we have an initialised inode buffer that is up to date but has an -EIO state registered against it. When we finally get to recovering an inode in that buffer: inode item recovery xfs_trans_read_buffer find buffer lock buffer sees XBF_DONE is set, returns buffer sees bp->b_error is set fail log recovery! Essentially, we need xfs_trans_get_buf_map() to clear the error status of the buffer when doing a lookup. This function returns uninitialised buffers, so the buffer returned can not be in an error state and none of the code that uses this function expects b_error to be set on return. Indeed, there is an ASSERT(!bp->b_error); in the transaction case in xfs_trans_get_buf_map() that would have caught this if log recovery used transactions.... This patch firstly changes the inode readahead failure to set -EIO on the buffer, and secondly changes xfs_buf_get_map() to never return a buffer with an error state set so this first change doesn't cause unexpected log recovery failures. cc: <stable@vger.kernel.org> # 3.12 - current Signed-off-by: Dave Chinner <dchinner@redhat.com> Reviewed-by: Brian Foster <bfoster@redhat.com> Signed-off-by: Dave Chinner <david@fromorbit.com>
2016-01-12 04:03:44 +08:00
xfs_buf_ioerror(bp, -EIO);
return;
}
#ifdef DEBUG
xfs_alert(mp,
"bad inode magic/vsn daddr %lld #%d (magic=%x)",
(unsigned long long)bp->b_bn, i,
be16_to_cpu(dip->di_magic));
#endif
xfs_buf_verifier_error(bp, -EFSCORRUPTED,
__func__, dip, sizeof(*dip),
NULL);
return;
}
}
}
static void
xfs_inode_buf_read_verify(
struct xfs_buf *bp)
{
xfs_inode_buf_verify(bp, false);
}
static void
xfs_inode_buf_readahead_verify(
struct xfs_buf *bp)
{
xfs_inode_buf_verify(bp, true);
}
static void
xfs_inode_buf_write_verify(
struct xfs_buf *bp)
{
xfs_inode_buf_verify(bp, false);
}
const struct xfs_buf_ops xfs_inode_buf_ops = {
.name = "xfs_inode",
.magic16 = { cpu_to_be16(XFS_DINODE_MAGIC),
cpu_to_be16(XFS_DINODE_MAGIC) },
.verify_read = xfs_inode_buf_read_verify,
.verify_write = xfs_inode_buf_write_verify,
};
const struct xfs_buf_ops xfs_inode_buf_ra_ops = {
.name = "xfs_inode_ra",
.magic16 = { cpu_to_be16(XFS_DINODE_MAGIC),
cpu_to_be16(XFS_DINODE_MAGIC) },
.verify_read = xfs_inode_buf_readahead_verify,
.verify_write = xfs_inode_buf_write_verify,
};
/*
* This routine is called to map an inode to the buffer containing the on-disk
* version of the inode. It returns a pointer to the buffer containing the
* on-disk inode in the bpp parameter.
*/
int
xfs_imap_to_bp(
struct xfs_mount *mp,
struct xfs_trans *tp,
struct xfs_imap *imap,
struct xfs_buf **bpp)
{
return xfs_trans_read_buf(mp, tp, mp->m_ddev_targp, imap->im_blkno,
imap->im_len, XBF_UNMAPPED, bpp,
&xfs_inode_buf_ops);
}
static inline struct timespec64 xfs_inode_decode_bigtime(uint64_t ts)
{
struct timespec64 tv;
uint32_t n;
tv.tv_sec = xfs_bigtime_to_unix(div_u64_rem(ts, NSEC_PER_SEC, &n));
tv.tv_nsec = n;
return tv;
}
/* Convert an ondisk timestamp to an incore timestamp. */
struct timespec64
xfs_inode_from_disk_ts(
struct xfs_dinode *dip,
const xfs_timestamp_t ts)
{
struct timespec64 tv;
struct xfs_legacy_timestamp *lts;
if (xfs_dinode_has_bigtime(dip))
return xfs_inode_decode_bigtime(be64_to_cpu(ts));
lts = (struct xfs_legacy_timestamp *)&ts;
tv.tv_sec = (int)be32_to_cpu(lts->t_sec);
tv.tv_nsec = (int)be32_to_cpu(lts->t_nsec);
return tv;
}
int
xfs_inode_from_disk(
struct xfs_inode *ip,
struct xfs_dinode *from)
{
struct inode *inode = VFS_I(ip);
int error;
xfs_failaddr_t fa;
ASSERT(ip->i_cowfp == NULL);
ASSERT(ip->i_afp == NULL);
fa = xfs_dinode_verify(ip->i_mount, ip->i_ino, from);
if (fa) {
xfs_inode_verifier_error(ip, -EFSCORRUPTED, "dinode", from,
sizeof(*from), fa);
return -EFSCORRUPTED;
}
/*
* First get the permanent information that is needed to allocate an
* inode. If the inode is unused, mode is zero and we shouldn't mess
* with the uninitialized part of it.
*/
if (!xfs_has_v3inodes(ip->i_mount))
ip->i_flushiter = be16_to_cpu(from->di_flushiter);
inode->i_generation = be32_to_cpu(from->di_gen);
inode->i_mode = be16_to_cpu(from->di_mode);
if (!inode->i_mode)
return 0;
/*
* Convert v1 inodes immediately to v2 inode format as this is the
* minimum inode version format we support in the rest of the code.
* They will also be unconditionally written back to disk as v2 inodes.
*/
if (unlikely(from->di_version == 1)) {
set_nlink(inode, be16_to_cpu(from->di_onlink));
ip->i_projid = 0;
} else {
set_nlink(inode, be32_to_cpu(from->di_nlink));
ip->i_projid = (prid_t)be16_to_cpu(from->di_projid_hi) << 16 |
be16_to_cpu(from->di_projid_lo);
}
i_uid_write(inode, be32_to_cpu(from->di_uid));
i_gid_write(inode, be32_to_cpu(from->di_gid));
/*
* Time is signed, so need to convert to signed 32 bit before
* storing in inode timestamp which may be 64 bit. Otherwise
* a time before epoch is converted to a time long after epoch
* on 64 bit systems.
*/
inode->i_atime = xfs_inode_from_disk_ts(from, from->di_atime);
inode->i_mtime = xfs_inode_from_disk_ts(from, from->di_mtime);
inode->i_ctime = xfs_inode_from_disk_ts(from, from->di_ctime);
ip->i_disk_size = be64_to_cpu(from->di_size);
ip->i_nblocks = be64_to_cpu(from->di_nblocks);
ip->i_extsize = be32_to_cpu(from->di_extsize);
ip->i_forkoff = from->di_forkoff;
ip->i_diflags = be16_to_cpu(from->di_flags);
if (from->di_dmevmask || from->di_dmstate)
xfs_iflags_set(ip, XFS_IPRESERVE_DM_FIELDS);
if (xfs_has_v3inodes(ip->i_mount)) {
inode_set_iversion_queried(inode,
be64_to_cpu(from->di_changecount));
ip->i_crtime = xfs_inode_from_disk_ts(from, from->di_crtime);
ip->i_diflags2 = be64_to_cpu(from->di_flags2);
ip->i_cowextsize = be32_to_cpu(from->di_cowextsize);
}
error = xfs_iformat_data_fork(ip, from);
if (error)
return error;
if (from->di_forkoff) {
error = xfs_iformat_attr_fork(ip, from);
if (error)
goto out_destroy_data_fork;
}
if (xfs_is_reflink_inode(ip))
xfs_ifork_init_cow(ip);
return 0;
out_destroy_data_fork:
xfs_idestroy_fork(&ip->i_df);
return error;
}
/* Convert an incore timestamp to an ondisk timestamp. */
static inline xfs_timestamp_t
xfs_inode_to_disk_ts(
struct xfs_inode *ip,
const struct timespec64 tv)
{
struct xfs_legacy_timestamp *lts;
xfs_timestamp_t ts;
if (xfs_inode_has_bigtime(ip))
return cpu_to_be64(xfs_inode_encode_bigtime(tv));
lts = (struct xfs_legacy_timestamp *)&ts;
lts->t_sec = cpu_to_be32(tv.tv_sec);
lts->t_nsec = cpu_to_be32(tv.tv_nsec);
return ts;
}
void
xfs_inode_to_disk(
struct xfs_inode *ip,
struct xfs_dinode *to,
xfs_lsn_t lsn)
{
struct inode *inode = VFS_I(ip);
to->di_magic = cpu_to_be16(XFS_DINODE_MAGIC);
to->di_onlink = 0;
to->di_format = xfs_ifork_format(&ip->i_df);
to->di_uid = cpu_to_be32(i_uid_read(inode));
to->di_gid = cpu_to_be32(i_gid_read(inode));
to->di_projid_lo = cpu_to_be16(ip->i_projid & 0xffff);
to->di_projid_hi = cpu_to_be16(ip->i_projid >> 16);
memset(to->di_pad, 0, sizeof(to->di_pad));
to->di_atime = xfs_inode_to_disk_ts(ip, inode->i_atime);
to->di_mtime = xfs_inode_to_disk_ts(ip, inode->i_mtime);
to->di_ctime = xfs_inode_to_disk_ts(ip, inode->i_ctime);
to->di_nlink = cpu_to_be32(inode->i_nlink);
to->di_gen = cpu_to_be32(inode->i_generation);
to->di_mode = cpu_to_be16(inode->i_mode);
to->di_size = cpu_to_be64(ip->i_disk_size);
to->di_nblocks = cpu_to_be64(ip->i_nblocks);
to->di_extsize = cpu_to_be32(ip->i_extsize);
to->di_nextents = cpu_to_be32(xfs_ifork_nextents(&ip->i_df));
to->di_anextents = cpu_to_be16(xfs_ifork_nextents(ip->i_afp));
to->di_forkoff = ip->i_forkoff;
to->di_aformat = xfs_ifork_format(ip->i_afp);
to->di_flags = cpu_to_be16(ip->i_diflags);
if (xfs_has_v3inodes(ip->i_mount)) {
to->di_version = 3;
to->di_changecount = cpu_to_be64(inode_peek_iversion(inode));
to->di_crtime = xfs_inode_to_disk_ts(ip, ip->i_crtime);
to->di_flags2 = cpu_to_be64(ip->i_diflags2);
to->di_cowextsize = cpu_to_be32(ip->i_cowextsize);
to->di_ino = cpu_to_be64(ip->i_ino);
to->di_lsn = cpu_to_be64(lsn);
memset(to->di_pad2, 0, sizeof(to->di_pad2));
uuid_copy(&to->di_uuid, &ip->i_mount->m_sb.sb_meta_uuid);
to->di_flushiter = 0;
} else {
to->di_version = 2;
to->di_flushiter = cpu_to_be16(ip->i_flushiter);
}
}
static xfs_failaddr_t
xfs_dinode_verify_fork(
struct xfs_dinode *dip,
struct xfs_mount *mp,
int whichfork)
{
uint32_t di_nextents = XFS_DFORK_NEXTENTS(dip, whichfork);
switch (XFS_DFORK_FORMAT(dip, whichfork)) {
case XFS_DINODE_FMT_LOCAL:
/*
* no local regular files yet
*/
if (whichfork == XFS_DATA_FORK) {
if (S_ISREG(be16_to_cpu(dip->di_mode)))
return __this_address;
if (be64_to_cpu(dip->di_size) >
XFS_DFORK_SIZE(dip, mp, whichfork))
return __this_address;
}
if (di_nextents)
return __this_address;
break;
case XFS_DINODE_FMT_EXTENTS:
if (di_nextents > XFS_DFORK_MAXEXT(dip, mp, whichfork))
return __this_address;
break;
case XFS_DINODE_FMT_BTREE:
if (whichfork == XFS_ATTR_FORK) {
if (di_nextents > MAXAEXTNUM)
return __this_address;
} else if (di_nextents > MAXEXTNUM) {
return __this_address;
}
break;
default:
return __this_address;
}
return NULL;
}
static xfs_failaddr_t
xfs_dinode_verify_forkoff(
struct xfs_dinode *dip,
struct xfs_mount *mp)
{
if (!dip->di_forkoff)
return NULL;
switch (dip->di_format) {
case XFS_DINODE_FMT_DEV:
if (dip->di_forkoff != (roundup(sizeof(xfs_dev_t), 8) >> 3))
return __this_address;
break;
case XFS_DINODE_FMT_LOCAL: /* fall through ... */
case XFS_DINODE_FMT_EXTENTS: /* fall through ... */
case XFS_DINODE_FMT_BTREE:
if (dip->di_forkoff >= (XFS_LITINO(mp) >> 3))
return __this_address;
break;
default:
return __this_address;
}
return NULL;
}
xfs_failaddr_t
xfs_dinode_verify(
struct xfs_mount *mp,
xfs_ino_t ino,
struct xfs_dinode *dip)
{
xfs_failaddr_t fa;
uint16_t mode;
uint16_t flags;
uint64_t flags2;
uint64_t di_size;
if (dip->di_magic != cpu_to_be16(XFS_DINODE_MAGIC))
return __this_address;
/* Verify v3 integrity information first */
if (dip->di_version >= 3) {
if (!xfs_has_v3inodes(mp))
return __this_address;
if (!xfs_verify_cksum((char *)dip, mp->m_sb.sb_inodesize,
XFS_DINODE_CRC_OFF))
return __this_address;
if (be64_to_cpu(dip->di_ino) != ino)
return __this_address;
if (!uuid_equal(&dip->di_uuid, &mp->m_sb.sb_meta_uuid))
return __this_address;
}
/* don't allow invalid i_size */
di_size = be64_to_cpu(dip->di_size);
if (di_size & (1ULL << 63))
return __this_address;
mode = be16_to_cpu(dip->di_mode);
if (mode && xfs_mode_to_ftype(mode) == XFS_DIR3_FT_UNKNOWN)
return __this_address;
/* No zero-length symlinks/dirs. */
if ((S_ISLNK(mode) || S_ISDIR(mode)) && di_size == 0)
return __this_address;
/* Fork checks carried over from xfs_iformat_fork */
if (mode &&
be32_to_cpu(dip->di_nextents) + be16_to_cpu(dip->di_anextents) >
be64_to_cpu(dip->di_nblocks))
return __this_address;
if (mode && XFS_DFORK_BOFF(dip) > mp->m_sb.sb_inodesize)
return __this_address;
flags = be16_to_cpu(dip->di_flags);
if (mode && (flags & XFS_DIFLAG_REALTIME) && !mp->m_rtdev_targp)
return __this_address;
/* check for illegal values of forkoff */
fa = xfs_dinode_verify_forkoff(dip, mp);
if (fa)
return fa;
/* Do we have appropriate data fork formats for the mode? */
switch (mode & S_IFMT) {
case S_IFIFO:
case S_IFCHR:
case S_IFBLK:
case S_IFSOCK:
if (dip->di_format != XFS_DINODE_FMT_DEV)
return __this_address;
break;
case S_IFREG:
case S_IFLNK:
case S_IFDIR:
fa = xfs_dinode_verify_fork(dip, mp, XFS_DATA_FORK);
if (fa)
return fa;
break;
case 0:
/* Uninitialized inode ok. */
break;
default:
return __this_address;
}
if (dip->di_forkoff) {
fa = xfs_dinode_verify_fork(dip, mp, XFS_ATTR_FORK);
if (fa)
return fa;
} else {
/*
* If there is no fork offset, this may be a freshly-made inode
* in a new disk cluster, in which case di_aformat is zeroed.
* Otherwise, such an inode must be in EXTENTS format; this goes
* for freed inodes as well.
*/
switch (dip->di_aformat) {
case 0:
case XFS_DINODE_FMT_EXTENTS:
break;
default:
return __this_address;
}
if (dip->di_anextents)
return __this_address;
}
/* extent size hint validation */
fa = xfs_inode_validate_extsize(mp, be32_to_cpu(dip->di_extsize),
mode, flags);
if (fa)
return fa;
/* only version 3 or greater inodes are extensively verified here */
if (dip->di_version < 3)
return NULL;
flags2 = be64_to_cpu(dip->di_flags2);
/* don't allow reflink/cowextsize if we don't have reflink */
if ((flags2 & (XFS_DIFLAG2_REFLINK | XFS_DIFLAG2_COWEXTSIZE)) &&
!xfs_has_reflink(mp))
return __this_address;
/* only regular files get reflink */
if ((flags2 & XFS_DIFLAG2_REFLINK) && (mode & S_IFMT) != S_IFREG)
return __this_address;
/* don't let reflink and realtime mix */
if ((flags2 & XFS_DIFLAG2_REFLINK) && (flags & XFS_DIFLAG_REALTIME))
return __this_address;
/* COW extent size hint validation */
fa = xfs_inode_validate_cowextsize(mp, be32_to_cpu(dip->di_cowextsize),
mode, flags, flags2);
if (fa)
return fa;
/* bigtime iflag can only happen on bigtime filesystems */
if (xfs_dinode_has_bigtime(dip) &&
!xfs_has_bigtime(mp))
return __this_address;
return NULL;
}
void
xfs_dinode_calc_crc(
struct xfs_mount *mp,
struct xfs_dinode *dip)
{
uint32_t crc;
if (dip->di_version < 3)
return;
ASSERT(xfs_has_crc(mp));
crc = xfs_start_cksum_update((char *)dip, mp->m_sb.sb_inodesize,
XFS_DINODE_CRC_OFF);
dip->di_crc = xfs_end_cksum(crc);
}
/*
* Validate di_extsize hint.
*
* 1. Extent size hint is only valid for directories and regular files.
* 2. FS_XFLAG_EXTSIZE is only valid for regular files.
* 3. FS_XFLAG_EXTSZINHERIT is only valid for directories.
* 4. Hint cannot be larger than MAXTEXTLEN.
* 5. Can be changed on directories at any time.
* 6. Hint value of 0 turns off hints, clears inode flags.
* 7. Extent size must be a multiple of the appropriate block size.
* For realtime files, this is the rt extent size.
* 8. For non-realtime files, the extent size hint must be limited
* to half the AG size to avoid alignment extending the extent beyond the
* limits of the AG.
*/
xfs_failaddr_t
xfs_inode_validate_extsize(
struct xfs_mount *mp,
uint32_t extsize,
uint16_t mode,
uint16_t flags)
{
bool rt_flag;
bool hint_flag;
bool inherit_flag;
uint32_t extsize_bytes;
uint32_t blocksize_bytes;
rt_flag = (flags & XFS_DIFLAG_REALTIME);
hint_flag = (flags & XFS_DIFLAG_EXTSIZE);
inherit_flag = (flags & XFS_DIFLAG_EXTSZINHERIT);
extsize_bytes = XFS_FSB_TO_B(mp, extsize);
xfs: validate extsz hints against rt extent size when rtinherit is set The RTINHERIT bit can be set on a directory so that newly created regular files will have the REALTIME bit set to store their data on the realtime volume. If an extent size hint (and EXTSZINHERIT) are set on the directory, the hint will also be copied into the new file. As pointed out in previous patches, for realtime files we require the extent size hint be an integer multiple of the realtime extent, but we don't perform the same validation on a directory with both RTINHERIT and EXTSZINHERIT set, even though the only use-case of that combination is to propagate extent size hints into new realtime files. This leads to inode corruption errors when the bad values are propagated. Because there may be existing filesystems with such a configuration, we cannot simply amend the inode verifier to trip on these directories and call it a day because that will cause previously "working" filesystems to start throwing errors abruptly. Note that it's valid to have directories with rtinherit set even if there is no realtime volume, in which case the problem does not manifest because rtinherit is ignored if there's no realtime device; and it's possible that someone set the flag, crashed, repaired the filesystem (which clears the hint on the realtime file) and continued. Therefore, mitigate this issue in several ways: First, if we try to write out an inode with both rtinherit/extszinherit set and an unaligned extent size hint, turn off the hint to correct the error. Second, if someone tries to misconfigure a directory via the fssetxattr ioctl, fail the ioctl. Third, reverify both extent size hint values when we propagate heritable inode attributes from parent to child, to prevent misconfigurations from spreading. Signed-off-by: Darrick J. Wong <djwong@kernel.org> Reviewed-by: Carlos Maiolino <cmaiolino@redhat.com> Reviewed-by: Brian Foster <bfoster@redhat.com>
2021-05-13 03:51:26 +08:00
/*
* This comment describes a historic gap in this verifier function.
*
* For a directory with both RTINHERIT and EXTSZINHERIT flags set, this
* function has never checked that the extent size hint is an integer
* multiple of the realtime extent size. Since we allow users to set
* this combination on non-rt filesystems /and/ to change the rt
* extent size when adding a rt device to a filesystem, the net effect
* is that users can configure a filesystem anticipating one rt
* geometry and change their minds later. Directories do not use the
* extent size hint, so this is harmless for them.
xfs: validate extsz hints against rt extent size when rtinherit is set The RTINHERIT bit can be set on a directory so that newly created regular files will have the REALTIME bit set to store their data on the realtime volume. If an extent size hint (and EXTSZINHERIT) are set on the directory, the hint will also be copied into the new file. As pointed out in previous patches, for realtime files we require the extent size hint be an integer multiple of the realtime extent, but we don't perform the same validation on a directory with both RTINHERIT and EXTSZINHERIT set, even though the only use-case of that combination is to propagate extent size hints into new realtime files. This leads to inode corruption errors when the bad values are propagated. Because there may be existing filesystems with such a configuration, we cannot simply amend the inode verifier to trip on these directories and call it a day because that will cause previously "working" filesystems to start throwing errors abruptly. Note that it's valid to have directories with rtinherit set even if there is no realtime volume, in which case the problem does not manifest because rtinherit is ignored if there's no realtime device; and it's possible that someone set the flag, crashed, repaired the filesystem (which clears the hint on the realtime file) and continued. Therefore, mitigate this issue in several ways: First, if we try to write out an inode with both rtinherit/extszinherit set and an unaligned extent size hint, turn off the hint to correct the error. Second, if someone tries to misconfigure a directory via the fssetxattr ioctl, fail the ioctl. Third, reverify both extent size hint values when we propagate heritable inode attributes from parent to child, to prevent misconfigurations from spreading. Signed-off-by: Darrick J. Wong <djwong@kernel.org> Reviewed-by: Carlos Maiolino <cmaiolino@redhat.com> Reviewed-by: Brian Foster <bfoster@redhat.com>
2021-05-13 03:51:26 +08:00
*
* If a directory with a misaligned extent size hint is allowed to
* propagate that hint into a new regular realtime file, the result
* is that the inode cluster buffer verifier will trigger a corruption
* shutdown the next time it is run, because the verifier has always
* enforced the alignment rule for regular files.
xfs: validate extsz hints against rt extent size when rtinherit is set The RTINHERIT bit can be set on a directory so that newly created regular files will have the REALTIME bit set to store their data on the realtime volume. If an extent size hint (and EXTSZINHERIT) are set on the directory, the hint will also be copied into the new file. As pointed out in previous patches, for realtime files we require the extent size hint be an integer multiple of the realtime extent, but we don't perform the same validation on a directory with both RTINHERIT and EXTSZINHERIT set, even though the only use-case of that combination is to propagate extent size hints into new realtime files. This leads to inode corruption errors when the bad values are propagated. Because there may be existing filesystems with such a configuration, we cannot simply amend the inode verifier to trip on these directories and call it a day because that will cause previously "working" filesystems to start throwing errors abruptly. Note that it's valid to have directories with rtinherit set even if there is no realtime volume, in which case the problem does not manifest because rtinherit is ignored if there's no realtime device; and it's possible that someone set the flag, crashed, repaired the filesystem (which clears the hint on the realtime file) and continued. Therefore, mitigate this issue in several ways: First, if we try to write out an inode with both rtinherit/extszinherit set and an unaligned extent size hint, turn off the hint to correct the error. Second, if someone tries to misconfigure a directory via the fssetxattr ioctl, fail the ioctl. Third, reverify both extent size hint values when we propagate heritable inode attributes from parent to child, to prevent misconfigurations from spreading. Signed-off-by: Darrick J. Wong <djwong@kernel.org> Reviewed-by: Carlos Maiolino <cmaiolino@redhat.com> Reviewed-by: Brian Foster <bfoster@redhat.com>
2021-05-13 03:51:26 +08:00
*
* Because we allow administrators to set a new rt extent size when
* adding a rt section, we cannot add a check to this verifier because
* that will result a new source of directory corruption errors when
* reading an existing filesystem. Instead, we rely on callers to
* decide when alignment checks are appropriate, and fix things up as
* needed.
xfs: validate extsz hints against rt extent size when rtinherit is set The RTINHERIT bit can be set on a directory so that newly created regular files will have the REALTIME bit set to store their data on the realtime volume. If an extent size hint (and EXTSZINHERIT) are set on the directory, the hint will also be copied into the new file. As pointed out in previous patches, for realtime files we require the extent size hint be an integer multiple of the realtime extent, but we don't perform the same validation on a directory with both RTINHERIT and EXTSZINHERIT set, even though the only use-case of that combination is to propagate extent size hints into new realtime files. This leads to inode corruption errors when the bad values are propagated. Because there may be existing filesystems with such a configuration, we cannot simply amend the inode verifier to trip on these directories and call it a day because that will cause previously "working" filesystems to start throwing errors abruptly. Note that it's valid to have directories with rtinherit set even if there is no realtime volume, in which case the problem does not manifest because rtinherit is ignored if there's no realtime device; and it's possible that someone set the flag, crashed, repaired the filesystem (which clears the hint on the realtime file) and continued. Therefore, mitigate this issue in several ways: First, if we try to write out an inode with both rtinherit/extszinherit set and an unaligned extent size hint, turn off the hint to correct the error. Second, if someone tries to misconfigure a directory via the fssetxattr ioctl, fail the ioctl. Third, reverify both extent size hint values when we propagate heritable inode attributes from parent to child, to prevent misconfigurations from spreading. Signed-off-by: Darrick J. Wong <djwong@kernel.org> Reviewed-by: Carlos Maiolino <cmaiolino@redhat.com> Reviewed-by: Brian Foster <bfoster@redhat.com>
2021-05-13 03:51:26 +08:00
*/
if (rt_flag)
blocksize_bytes = XFS_FSB_TO_B(mp, mp->m_sb.sb_rextsize);
else
blocksize_bytes = mp->m_sb.sb_blocksize;
if ((hint_flag || inherit_flag) && !(S_ISDIR(mode) || S_ISREG(mode)))
return __this_address;
if (hint_flag && !S_ISREG(mode))
return __this_address;
if (inherit_flag && !S_ISDIR(mode))
return __this_address;
if ((hint_flag || inherit_flag) && extsize == 0)
return __this_address;
/* free inodes get flags set to zero but extsize remains */
if (mode && !(hint_flag || inherit_flag) && extsize != 0)
return __this_address;
if (extsize_bytes % blocksize_bytes)
return __this_address;
if (extsize > MAXEXTLEN)
return __this_address;
if (!rt_flag && extsize > mp->m_sb.sb_agblocks / 2)
return __this_address;
return NULL;
}
/*
* Validate di_cowextsize hint.
*
* 1. CoW extent size hint can only be set if reflink is enabled on the fs.
* The inode does not have to have any shared blocks, but it must be a v3.
* 2. FS_XFLAG_COWEXTSIZE is only valid for directories and regular files;
* for a directory, the hint is propagated to new files.
* 3. Can be changed on files & directories at any time.
* 4. Hint value of 0 turns off hints, clears inode flags.
* 5. Extent size must be a multiple of the appropriate block size.
* 6. The extent size hint must be limited to half the AG size to avoid
* alignment extending the extent beyond the limits of the AG.
*/
xfs_failaddr_t
xfs_inode_validate_cowextsize(
struct xfs_mount *mp,
uint32_t cowextsize,
uint16_t mode,
uint16_t flags,
uint64_t flags2)
{
bool rt_flag;
bool hint_flag;
uint32_t cowextsize_bytes;
rt_flag = (flags & XFS_DIFLAG_REALTIME);
hint_flag = (flags2 & XFS_DIFLAG2_COWEXTSIZE);
cowextsize_bytes = XFS_FSB_TO_B(mp, cowextsize);
if (hint_flag && !xfs_has_reflink(mp))
return __this_address;
if (hint_flag && !(S_ISDIR(mode) || S_ISREG(mode)))
return __this_address;
if (hint_flag && cowextsize == 0)
return __this_address;
/* free inodes get flags set to zero but cowextsize remains */
if (mode && !hint_flag && cowextsize != 0)
return __this_address;
if (hint_flag && rt_flag)
return __this_address;
if (cowextsize_bytes % mp->m_sb.sb_blocksize)
return __this_address;
if (cowextsize > MAXEXTLEN)
return __this_address;
if (cowextsize > mp->m_sb.sb_agblocks / 2)
return __this_address;
return NULL;
}