diff options
| -rw-r--r-- | fs/xfs/xfs_ialloc.c | 121 |
1 files changed, 78 insertions, 43 deletions
diff --git a/fs/xfs/xfs_ialloc.c b/fs/xfs/xfs_ialloc.c index 9d884c127bb9..0c946c8e05da 100644 --- a/fs/xfs/xfs_ialloc.c +++ b/fs/xfs/xfs_ialloc.c @@ -1203,6 +1203,63 @@ error0: return error; } +STATIC int +xfs_imap_lookup( + struct xfs_mount *mp, + struct xfs_trans *tp, + xfs_agnumber_t agno, + xfs_agino_t agino, + xfs_agblock_t agbno, + xfs_agblock_t *chunk_agbno, + xfs_agblock_t *offset_agbno, + int flags) +{ + struct xfs_inobt_rec_incore rec; + struct xfs_btree_cur *cur; + struct xfs_buf *agbp; + xfs_agino_t startino; + int error; + int i; + + error = xfs_ialloc_read_agi(mp, tp, agno, &agbp); + if (error) { + xfs_fs_cmn_err(CE_ALERT, mp, "xfs_imap: " + "xfs_ialloc_read_agi() returned " + "error %d, agno %d", + error, agno); + return error; + } + + /* + * derive and lookup the exact inode record for the given agino. If the + * record cannot be found, then it's an invalid inode number and we + * should abort. + */ + cur = xfs_inobt_init_cursor(mp, tp, agbp, agno); + startino = agino & ~(XFS_IALLOC_INODES(mp) - 1); + error = xfs_inobt_lookup(cur, startino, XFS_LOOKUP_EQ, &i); + if (!error) { + if (i) + error = xfs_inobt_get_rec(cur, &rec, &i); + if (!error && i == 0) + error = EINVAL; + } + + xfs_trans_brelse(tp, agbp); + xfs_btree_del_cursor(cur, XFS_BTREE_NOERROR); + if (error) + return error; + + /* for untrusted inodes check it is allocated first */ + if ((flags & XFS_IGET_BULKSTAT) && + (rec.ir_free & XFS_INOBT_MASK(agino - rec.ir_startino))) + return EINVAL; + + *chunk_agbno = XFS_AGINO_TO_AGBNO(mp, rec.ir_startino); + *offset_agbno = agbno - *chunk_agbno; + return 0; +} + /* * Return the location of the inode in imap, for mapping it into a buffer. */ @@ -1263,6 +1320,23 @@ xfs_imap( return XFS_ERROR(EINVAL); } + blks_per_cluster = XFS_INODE_CLUSTER_SIZE(mp) >> mp->m_sb.sb_blocklog; + + /* + * For bulkstat and handle lookups, we have an untrusted inode number + * that we have to verify is valid. We cannot do this just by reading + * the inode buffer as it may have been unlinked and removed leaving + * inodes in stale state on disk. Hence we have to do a btree lookup + * in all cases where an untrusted inode number is passed. + */ + if (flags & XFS_IGET_BULKSTAT) { + error = xfs_imap_lookup(mp, tp, agno, agino, agbno, + &chunk_agbno, &offset_agbno, flags); + if (error) + return error; + goto out_map; + } + /* * If the inode cluster size is the same as the blocksize or * smaller we get to the buffer by simple arithmetics. @@ -1277,10 +1351,8 @@ xfs_imap( return 0; } - blks_per_cluster = XFS_INODE_CLUSTER_SIZE(mp) >> mp->m_sb.sb_blocklog; - /* - * If we get a block number passed from bulkstat we can use it to + * If we get a block number passed we can use it to * find the buffer easily. */ if (imap->im_blkno) { @@ -1304,50 +1376,13 @@ xfs_imap( offset_agbno = agbno & mp->m_inoalign_mask; chunk_agbno = agbno - offset_agbno; } else { - xfs_btree_cur_t *cur; /* inode btree cursor */ - xfs_inobt_rec_incore_t chunk_rec; - xfs_buf_t *agbp; /* agi buffer */ - int i; /* temp state */ - - error = xfs_ialloc_read_agi(mp, tp, agno, &agbp); - if (error) { - xfs_fs_cmn_err(CE_ALERT, mp, "xfs_imap: " - "xfs_ialloc_read_agi() returned " - "error %d, agno %d", - error, agno); - return error; - } - - cur = xfs_inobt_init_cursor(mp, tp, agbp, agno); - error = xfs_inobt_lookup(cur, agino, XFS_LOOKUP_LE, &i); - if (error) { - xfs_fs_cmn_err(CE_ALERT, mp, "xfs_imap: " - "xfs_inobt_lookup() failed"); - goto error0; - } - - error = xfs_inobt_get_rec(cur, &chunk_rec, &i); - if (error) { - xfs_fs_cmn_err(CE_ALERT, mp, "xfs_imap: " - "xfs_inobt_get_rec() failed"); - goto error0; - } - if (i == 0) { -#ifdef DEBUG - xfs_fs_cmn_err(CE_ALERT, mp, "xfs_imap: " - "xfs_inobt_get_rec() failed"); -#endif /* DEBUG */ - error = XFS_ERROR(EINVAL); - } - error0: - xfs_trans_brelse(tp, agbp); - xfs_btree_del_cursor(cur, XFS_BTREE_NOERROR); + error = xfs_imap_lookup(mp, tp, agno, agino, agbno, + &chunk_agbno, &offset_agbno, flags); if (error) return error; - chunk_agbno = XFS_AGINO_TO_AGBNO(mp, chunk_rec.ir_startino); - offset_agbno = agbno - chunk_agbno; } +out_map: ASSERT(agbno >= chunk_agbno); cluster_agbno = chunk_agbno + ((offset_agbno / blks_per_cluster) * blks_per_cluster); |