xfs: rework the inline directory verifiers

The inline directory verifiers should be called on the inode fork data,
which means after iformat_local on the read side, and prior to
ifork_flush on the write side.  This makes the fork verifier more
consistent with the way buffer verifiers work -- i.e. they will operate
on the memory buffer that the code will be reading and writing directly.

Furthermore, revise the verifier function to return -EFSCORRUPTED so
that we don't flood the logs with corruption messages and assert
notices.  This has been a particular problem with xfs/348, which
triggers the XFS_WANT_CORRUPTED_RETURN assertions, which halts the
kernel when CONFIG_XFS_DEBUG=y.  Disk corruption isn't supposed to do
that, at least not in a verifier.

Reviewed-by: Brian Foster <bfoster@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
---
v2: get the inode d_ops the proper way
v3: describe the bug that this patch fixes; no code changes
This commit is contained in:
Darrick J. Wong 2017-03-28 14:51:10 -07:00
parent c02ed2e75e
commit 005c5db8fd
5 changed files with 66 additions and 56 deletions

View File

@ -125,8 +125,7 @@ extern int xfs_dir2_sf_create(struct xfs_da_args *args, xfs_ino_t pino);
extern int xfs_dir2_sf_lookup(struct xfs_da_args *args);
extern int xfs_dir2_sf_removename(struct xfs_da_args *args);
extern int xfs_dir2_sf_replace(struct xfs_da_args *args);
extern int xfs_dir2_sf_verify(struct xfs_mount *mp, struct xfs_dir2_sf_hdr *sfp,
int size);
extern int xfs_dir2_sf_verify(struct xfs_inode *ip);
/* xfs_dir2_readdir.c */
extern int xfs_readdir(struct xfs_inode *dp, struct dir_context *ctx,

View File

@ -632,36 +632,49 @@ xfs_dir2_sf_check(
/* Verify the consistency of an inline directory. */
int
xfs_dir2_sf_verify(
struct xfs_mount *mp,
struct xfs_dir2_sf_hdr *sfp,
int size)
struct xfs_inode *ip)
{
struct xfs_mount *mp = ip->i_mount;
struct xfs_dir2_sf_hdr *sfp;
struct xfs_dir2_sf_entry *sfep;
struct xfs_dir2_sf_entry *next_sfep;
char *endp;
const struct xfs_dir_ops *dops;
struct xfs_ifork *ifp;
xfs_ino_t ino;
int i;
int i8count;
int offset;
int size;
int error;
__uint8_t filetype;
ASSERT(ip->i_d.di_format == XFS_DINODE_FMT_LOCAL);
/*
* xfs_iread calls us before xfs_setup_inode sets up ip->d_ops,
* so we can only trust the mountpoint to have the right pointer.
*/
dops = xfs_dir_get_ops(mp, NULL);
ifp = XFS_IFORK_PTR(ip, XFS_DATA_FORK);
sfp = (struct xfs_dir2_sf_hdr *)ifp->if_u1.if_data;
size = ifp->if_bytes;
/*
* Give up if the directory is way too short.
*/
XFS_WANT_CORRUPTED_RETURN(mp, size >
offsetof(struct xfs_dir2_sf_hdr, parent));
XFS_WANT_CORRUPTED_RETURN(mp, size >=
xfs_dir2_sf_hdr_size(sfp->i8count));
if (size <= offsetof(struct xfs_dir2_sf_hdr, parent) ||
size < xfs_dir2_sf_hdr_size(sfp->i8count))
return -EFSCORRUPTED;
endp = (char *)sfp + size;
/* Check .. entry */
ino = dops->sf_get_parent_ino(sfp);
i8count = ino > XFS_DIR2_MAX_SHORT_INUM;
XFS_WANT_CORRUPTED_RETURN(mp, !xfs_dir_ino_validate(mp, ino));
error = xfs_dir_ino_validate(mp, ino);
if (error)
return error;
offset = dops->data_first_offset;
/* Check all reported entries */
@ -672,12 +685,12 @@ xfs_dir2_sf_verify(
* Check the fixed-offset parts of the structure are
* within the data buffer.
*/
XFS_WANT_CORRUPTED_RETURN(mp,
((char *)sfep + sizeof(*sfep)) < endp);
if (((char *)sfep + sizeof(*sfep)) >= endp)
return -EFSCORRUPTED;
/* Don't allow names with known bad length. */
XFS_WANT_CORRUPTED_RETURN(mp, sfep->namelen > 0);
XFS_WANT_CORRUPTED_RETURN(mp, sfep->namelen < MAXNAMELEN);
if (sfep->namelen == 0)
return -EFSCORRUPTED;
/*
* Check that the variable-length part of the structure is
@ -685,33 +698,39 @@ xfs_dir2_sf_verify(
* name component, so nextentry is an acceptable test.
*/
next_sfep = dops->sf_nextentry(sfp, sfep);
XFS_WANT_CORRUPTED_RETURN(mp, endp >= (char *)next_sfep);
if (endp < (char *)next_sfep)
return -EFSCORRUPTED;
/* Check that the offsets always increase. */
XFS_WANT_CORRUPTED_RETURN(mp,
xfs_dir2_sf_get_offset(sfep) >= offset);
if (xfs_dir2_sf_get_offset(sfep) < offset)
return -EFSCORRUPTED;
/* Check the inode number. */
ino = dops->sf_get_ino(sfp, sfep);
i8count += ino > XFS_DIR2_MAX_SHORT_INUM;
XFS_WANT_CORRUPTED_RETURN(mp, !xfs_dir_ino_validate(mp, ino));
error = xfs_dir_ino_validate(mp, ino);
if (error)
return error;
/* Check the file type. */
filetype = dops->sf_get_ftype(sfep);
XFS_WANT_CORRUPTED_RETURN(mp, filetype < XFS_DIR3_FT_MAX);
if (filetype >= XFS_DIR3_FT_MAX)
return -EFSCORRUPTED;
offset = xfs_dir2_sf_get_offset(sfep) +
dops->data_entsize(sfep->namelen);
sfep = next_sfep;
}
XFS_WANT_CORRUPTED_RETURN(mp, i8count == sfp->i8count);
XFS_WANT_CORRUPTED_RETURN(mp, (void *)sfep == (void *)endp);
if (i8count != sfp->i8count)
return -EFSCORRUPTED;
if ((void *)sfep != (void *)endp)
return -EFSCORRUPTED;
/* Make sure this whole thing ought to be in local format. */
XFS_WANT_CORRUPTED_RETURN(mp, offset +
(sfp->count + 2) * (uint)sizeof(xfs_dir2_leaf_entry_t) +
(uint)sizeof(xfs_dir2_block_tail_t) <= mp->m_dir_geo->blksize);
if (offset + (sfp->count + 2) * (uint)sizeof(xfs_dir2_leaf_entry_t) +
(uint)sizeof(xfs_dir2_block_tail_t) > mp->m_dir_geo->blksize)
return -EFSCORRUPTED;
return 0;
}

View File

@ -212,6 +212,16 @@ xfs_iformat_fork(
if (error)
return error;
/* Check inline dir contents. */
if (S_ISDIR(VFS_I(ip)->i_mode) &&
dip->di_format == XFS_DINODE_FMT_LOCAL) {
error = xfs_dir2_sf_verify(ip);
if (error) {
xfs_idestroy_fork(ip, XFS_DATA_FORK);
return error;
}
}
if (xfs_is_reflink_inode(ip)) {
ASSERT(ip->i_cowfp == NULL);
xfs_ifork_init_cow(ip);
@ -322,8 +332,6 @@ xfs_iformat_local(
int whichfork,
int size)
{
int error;
/*
* If the size is unreasonable, then something
* is wrong and we just bail out rather than crash in
@ -339,14 +347,6 @@ xfs_iformat_local(
return -EFSCORRUPTED;
}
if (S_ISDIR(VFS_I(ip)->i_mode) && whichfork == XFS_DATA_FORK) {
error = xfs_dir2_sf_verify(ip->i_mount,
(struct xfs_dir2_sf_hdr *)XFS_DFORK_DPTR(dip),
size);
if (error)
return error;
}
xfs_init_local_fork(ip, whichfork, XFS_DFORK_PTR(dip, whichfork), size);
return 0;
}
@ -867,7 +867,7 @@ xfs_iextents_copy(
* In these cases, the format always takes precedence, because the
* format indicates the current state of the fork.
*/
int
void
xfs_iflush_fork(
xfs_inode_t *ip,
xfs_dinode_t *dip,
@ -877,7 +877,6 @@ xfs_iflush_fork(
char *cp;
xfs_ifork_t *ifp;
xfs_mount_t *mp;
int error;
static const short brootflag[2] =
{ XFS_ILOG_DBROOT, XFS_ILOG_ABROOT };
static const short dataflag[2] =
@ -886,7 +885,7 @@ xfs_iflush_fork(
{ XFS_ILOG_DEXT, XFS_ILOG_AEXT };
if (!iip)
return 0;
return;
ifp = XFS_IFORK_PTR(ip, whichfork);
/*
* This can happen if we gave up in iformat in an error path,
@ -894,19 +893,12 @@ xfs_iflush_fork(
*/
if (!ifp) {
ASSERT(whichfork == XFS_ATTR_FORK);
return 0;
return;
}
cp = XFS_DFORK_PTR(dip, whichfork);
mp = ip->i_mount;
switch (XFS_IFORK_FORMAT(ip, whichfork)) {
case XFS_DINODE_FMT_LOCAL:
if (S_ISDIR(VFS_I(ip)->i_mode) && whichfork == XFS_DATA_FORK) {
error = xfs_dir2_sf_verify(mp,
(struct xfs_dir2_sf_hdr *)ifp->if_u1.if_data,
ifp->if_bytes);
if (error)
return error;
}
if ((iip->ili_fields & dataflag[whichfork]) &&
(ifp->if_bytes > 0)) {
ASSERT(ifp->if_u1.if_data != NULL);
@ -959,7 +951,6 @@ xfs_iflush_fork(
ASSERT(0);
break;
}
return 0;
}
/*

View File

@ -140,7 +140,7 @@ typedef struct xfs_ifork {
struct xfs_ifork *xfs_iext_state_to_fork(struct xfs_inode *ip, int state);
int xfs_iformat_fork(struct xfs_inode *, struct xfs_dinode *);
int xfs_iflush_fork(struct xfs_inode *, struct xfs_dinode *,
void xfs_iflush_fork(struct xfs_inode *, struct xfs_dinode *,
struct xfs_inode_log_item *, int);
void xfs_idestroy_fork(struct xfs_inode *, int);
void xfs_idata_realloc(struct xfs_inode *, int, int);

View File

@ -50,6 +50,7 @@
#include "xfs_log.h"
#include "xfs_bmap_btree.h"
#include "xfs_reflink.h"
#include "xfs_dir2_priv.h"
kmem_zone_t *xfs_inode_zone;
@ -3475,7 +3476,6 @@ xfs_iflush_int(
struct xfs_inode_log_item *iip = ip->i_itemp;
struct xfs_dinode *dip;
struct xfs_mount *mp = ip->i_mount;
int error;
ASSERT(xfs_isilocked(ip, XFS_ILOCK_EXCL|XFS_ILOCK_SHARED));
ASSERT(xfs_isiflocked(ip));
@ -3547,6 +3547,12 @@ xfs_iflush_int(
if (ip->i_d.di_version < 3)
ip->i_d.di_flushiter++;
/* Check the inline directory data. */
if (S_ISDIR(VFS_I(ip)->i_mode) &&
ip->i_d.di_format == XFS_DINODE_FMT_LOCAL &&
xfs_dir2_sf_verify(ip))
goto corrupt_out;
/*
* Copy the dirty parts of the inode into the on-disk inode. We always
* copy out the core of the inode, because if the inode is dirty at all
@ -3558,14 +3564,9 @@ xfs_iflush_int(
if (ip->i_d.di_flushiter == DI_MAX_FLUSH)
ip->i_d.di_flushiter = 0;
error = xfs_iflush_fork(ip, dip, iip, XFS_DATA_FORK);
if (error)
return error;
if (XFS_IFORK_Q(ip)) {
error = xfs_iflush_fork(ip, dip, iip, XFS_ATTR_FORK);
if (error)
return error;
}
xfs_iflush_fork(ip, dip, iip, XFS_DATA_FORK);
if (XFS_IFORK_Q(ip))
xfs_iflush_fork(ip, dip, iip, XFS_ATTR_FORK);
xfs_inobp_check(mp, bp);
/*