xfs: capture inode generation numbers in the ondisk exchmaps log item

Per some very late review comments, capture the generation numbers of
both inodes involved in a file content exchange operation so that we
don't accidentally target files with have been reallocated.

Signed-off-by: Darrick J. Wong <djwong@kernel.org>
Reviewed-by: Christoph Hellwig <hch@lst.de>
This commit is contained in:
Darrick J. Wong 2024-04-15 14:54:24 -07:00
parent b3e60f8483
commit 14f1999102
4 changed files with 55 additions and 5 deletions

View File

@ -896,6 +896,8 @@ struct xfs_xmi_log_format {
uint64_t xmi_inode1; /* inumber of first file */
uint64_t xmi_inode2; /* inumber of second file */
uint32_t xmi_igen1; /* generation of first file */
uint32_t xmi_igen2; /* generation of second file */
uint64_t xmi_startoff1; /* block offset into file1 */
uint64_t xmi_startoff2; /* block offset into file2 */
uint64_t xmi_blockcount; /* number of blocks */

View File

@ -123,6 +123,8 @@ bool xlog_is_buffer_cancelled(struct xlog *log, xfs_daddr_t blkno, uint len);
int xlog_recover_iget(struct xfs_mount *mp, xfs_ino_t ino,
struct xfs_inode **ipp);
int xlog_recover_iget_handle(struct xfs_mount *mp, xfs_ino_t ino, uint32_t gen,
struct xfs_inode **ipp);
void xlog_recover_release_intent(struct xlog *log, unsigned short intent_type,
uint64_t intent_id);
int xlog_alloc_buf_cancel_table(struct xlog *log);

View File

@ -231,7 +231,9 @@ xfs_exchmaps_create_intent(
xlf = &xmi_lip->xmi_format;
xlf->xmi_inode1 = xmi->xmi_ip1->i_ino;
xlf->xmi_igen1 = VFS_I(xmi->xmi_ip1)->i_generation;
xlf->xmi_inode2 = xmi->xmi_ip2->i_ino;
xlf->xmi_igen2 = VFS_I(xmi->xmi_ip2)->i_generation;
xlf->xmi_startoff1 = xmi->xmi_startoff1;
xlf->xmi_startoff2 = xmi->xmi_startoff2;
xlf->xmi_blockcount = xmi->xmi_blockcount;
@ -368,14 +370,25 @@ xfs_xmi_item_recover_intent(
/*
* Grab both inodes and set IRECOVERY to prevent trimming of post-eof
* mappings and freeing of unlinked inodes until we're totally done
* processing files.
* processing files. The ondisk format of this new log item contains
* file handle information, which is why recovery for other items do
* not check the inode generation number.
*/
error = xlog_recover_iget(mp, xlf->xmi_inode1, &ip1);
if (error)
error = xlog_recover_iget_handle(mp, xlf->xmi_inode1, xlf->xmi_igen1,
&ip1);
if (error) {
XFS_CORRUPTION_ERROR(__func__, XFS_ERRLEVEL_LOW, mp, xlf,
sizeof(*xlf));
return ERR_PTR(error);
error = xlog_recover_iget(mp, xlf->xmi_inode2, &ip2);
if (error)
}
error = xlog_recover_iget_handle(mp, xlf->xmi_inode2, xlf->xmi_igen2,
&ip2);
if (error) {
XFS_CORRUPTION_ERROR(__func__, XFS_ERRLEVEL_LOW, mp, xlf,
sizeof(*xlf));
goto err_rele1;
}
req->ip1 = ip1;
req->ip2 = ip2;
@ -485,6 +498,8 @@ xfs_exchmaps_relog_intent(
new_xlf->xmi_inode1 = old_xlf->xmi_inode1;
new_xlf->xmi_inode2 = old_xlf->xmi_inode2;
new_xlf->xmi_igen1 = old_xlf->xmi_igen1;
new_xlf->xmi_igen2 = old_xlf->xmi_igen2;
new_xlf->xmi_startoff1 = old_xlf->xmi_startoff1;
new_xlf->xmi_startoff2 = old_xlf->xmi_startoff2;
new_xlf->xmi_blockcount = old_xlf->xmi_blockcount;

View File

@ -1767,6 +1767,37 @@ xlog_recover_iget(
return 0;
}
/*
* Get an inode so that we can recover a log operation.
*
* Log intent items that target inodes effectively contain a file handle.
* Check that the generation number matches the intent item like we do for
* other file handles. Log intent items defined after this validation weakness
* was identified must use this function.
*/
int
xlog_recover_iget_handle(
struct xfs_mount *mp,
xfs_ino_t ino,
uint32_t gen,
struct xfs_inode **ipp)
{
struct xfs_inode *ip;
int error;
error = xlog_recover_iget(mp, ino, &ip);
if (error)
return error;
if (VFS_I(ip)->i_generation != gen) {
xfs_irele(ip);
return -EFSCORRUPTED;
}
*ipp = ip;
return 0;
}
/******************************************************************************
*
* Log recover routines