diff options
Diffstat (limited to 'fs/xfs/xfs_dir2_readdir.c')
| -rw-r--r-- | fs/xfs/xfs_dir2_readdir.c | 137 |
1 files changed, 73 insertions, 64 deletions
diff --git a/fs/xfs/xfs_dir2_readdir.c b/fs/xfs/xfs_dir2_readdir.c index 283df898dd9f..0d3b640cf1cc 100644 --- a/fs/xfs/xfs_dir2_readdir.c +++ b/fs/xfs/xfs_dir2_readdir.c @@ -17,6 +17,7 @@ #include "xfs_trace.h" #include "xfs_bmap.h" #include "xfs_trans.h" +#include "xfs_error.h" /* * Directory file type support functions @@ -47,6 +48,7 @@ xfs_dir2_sf_getdents( { int i; /* shortform entry number */ struct xfs_inode *dp = args->dp; /* incore directory inode */ + struct xfs_mount *mp = dp->i_mount; xfs_dir2_dataptr_t off; /* current entry's offset */ xfs_dir2_sf_entry_t *sfep; /* shortform directory entry */ xfs_dir2_sf_hdr_t *sfp; /* shortform structure */ @@ -68,15 +70,15 @@ xfs_dir2_sf_getdents( return 0; /* - * Precalculate offsets for . and .. as we will always need them. - * - * XXX(hch): the second argument is sometimes 0 and sometimes - * geo->datablk + * Precalculate offsets for "." and ".." as we will always need them. + * This relies on the fact that directories always start with the + * entries for "." and "..". */ dot_offset = xfs_dir2_db_off_to_dataptr(geo, geo->datablk, - dp->d_ops->data_dot_offset); + geo->data_entry_offset); dotdot_offset = xfs_dir2_db_off_to_dataptr(geo, geo->datablk, - dp->d_ops->data_dotdot_offset); + geo->data_entry_offset + + xfs_dir2_data_entsize(mp, sizeof(".") - 1)); /* * Put . entry unless we're starting past it. @@ -91,7 +93,7 @@ xfs_dir2_sf_getdents( * Put .. entry unless we're starting past it. */ if (ctx->pos <= dotdot_offset) { - ino = dp->d_ops->sf_get_parent_ino(sfp); + ino = xfs_dir2_sf_get_parent_ino(sfp); ctx->pos = dotdot_offset & 0x7fffffff; if (!dir_emit(ctx, "..", 2, ino, DT_DIR)) return 0; @@ -108,17 +110,21 @@ xfs_dir2_sf_getdents( xfs_dir2_sf_get_offset(sfep)); if (ctx->pos > off) { - sfep = dp->d_ops->sf_nextentry(sfp, sfep); + sfep = xfs_dir2_sf_nextentry(mp, sfp, sfep); continue; } - ino = dp->d_ops->sf_get_ino(sfp, sfep); - filetype = dp->d_ops->sf_get_ftype(sfep); + ino = xfs_dir2_sf_get_ino(mp, sfp, sfep); + filetype = xfs_dir2_sf_get_ftype(mp, sfep); ctx->pos = off & 0x7fffffff; + if (XFS_IS_CORRUPT(dp->i_mount, + !xfs_dir2_namecheck(sfep->name, + sfep->namelen))) + return -EFSCORRUPTED; if (!dir_emit(ctx, (char *)sfep->name, sfep->namelen, ino, - xfs_dir3_get_dtype(dp->i_mount, filetype))) + xfs_dir3_get_dtype(mp, filetype))) return 0; - sfep = dp->d_ops->sf_nextentry(sfp, sfep); + sfep = xfs_dir2_sf_nextentry(mp, sfp, sfep); } ctx->pos = xfs_dir2_db_off_to_dataptr(geo, geo->datablk + 1, 0) & @@ -135,17 +141,14 @@ xfs_dir2_block_getdents( struct dir_context *ctx) { struct xfs_inode *dp = args->dp; /* incore directory inode */ - xfs_dir2_data_hdr_t *hdr; /* block header */ struct xfs_buf *bp; /* buffer for block */ - xfs_dir2_data_entry_t *dep; /* block data entry */ - xfs_dir2_data_unused_t *dup; /* block unused entry */ - char *endptr; /* end of the data entries */ int error; /* error return value */ - char *ptr; /* current data entry */ int wantoff; /* starting block offset */ xfs_off_t cook; struct xfs_da_geometry *geo = args->geo; int lock_mode; + unsigned int offset; + unsigned int end; /* * If the block number in the offset is out of range, we're done. @@ -164,56 +167,55 @@ xfs_dir2_block_getdents( * We'll skip entries before this. */ wantoff = xfs_dir2_dataptr_to_off(geo, ctx->pos); - hdr = bp->b_addr; xfs_dir3_data_check(dp, bp); - /* - * Set up values for the loop. - */ - ptr = (char *)dp->d_ops->data_entry_p(hdr); - endptr = xfs_dir3_data_endp(geo, hdr); /* * Loop over the data portion of the block. * Each object is a real entry (dep) or an unused one (dup). */ - while (ptr < endptr) { + offset = geo->data_entry_offset; + end = xfs_dir3_data_end_offset(geo, bp->b_addr); + while (offset < end) { + struct xfs_dir2_data_unused *dup = bp->b_addr + offset; + struct xfs_dir2_data_entry *dep = bp->b_addr + offset; uint8_t filetype; - dup = (xfs_dir2_data_unused_t *)ptr; /* * Unused, skip it. */ if (be16_to_cpu(dup->freetag) == XFS_DIR2_DATA_FREE_TAG) { - ptr += be16_to_cpu(dup->length); + offset += be16_to_cpu(dup->length); continue; } - dep = (xfs_dir2_data_entry_t *)ptr; - /* * Bump pointer for the next iteration. */ - ptr += dp->d_ops->data_entsize(dep->namelen); + offset += xfs_dir2_data_entsize(dp->i_mount, dep->namelen); + /* * The entry is before the desired starting point, skip it. */ - if ((char *)dep - (char *)hdr < wantoff) + if (offset < wantoff) continue; - cook = xfs_dir2_db_off_to_dataptr(geo, geo->datablk, - (char *)dep - (char *)hdr); + cook = xfs_dir2_db_off_to_dataptr(geo, geo->datablk, offset); ctx->pos = cook & 0x7fffffff; - filetype = dp->d_ops->data_get_ftype(dep); + filetype = xfs_dir2_data_get_ftype(dp->i_mount, dep); /* * If it didn't fit, set the final offset to here & return. */ + if (XFS_IS_CORRUPT(dp->i_mount, + !xfs_dir2_namecheck(dep->name, + dep->namelen))) { + error = -EFSCORRUPTED; + goto out_rele; + } if (!dir_emit(ctx, (char *)dep->name, dep->namelen, be64_to_cpu(dep->inumber), - xfs_dir3_get_dtype(dp->i_mount, filetype))) { - xfs_trans_brelse(args->trans, bp); - return 0; - } + xfs_dir3_get_dtype(dp->i_mount, filetype))) + goto out_rele; } /* @@ -222,8 +224,9 @@ xfs_dir2_block_getdents( */ ctx->pos = xfs_dir2_db_off_to_dataptr(geo, geo->datablk + 1, 0) & 0x7fffffff; +out_rele: xfs_trans_brelse(args->trans, bp); - return 0; + return error; } /* @@ -276,7 +279,7 @@ xfs_dir2_leaf_readbuf( new_off = xfs_dir2_da_to_byte(geo, map.br_startoff); if (new_off > *cur_off) *cur_off = new_off; - error = xfs_dir3_data_read(args->trans, dp, map.br_startoff, -1, &bp); + error = xfs_dir3_data_read(args->trans, dp, map.br_startoff, 0, &bp); if (error) goto out; @@ -311,7 +314,8 @@ xfs_dir2_leaf_readbuf( break; } if (next_ra > *ra_blk) { - xfs_dir3_data_readahead(dp, next_ra, -2); + xfs_dir3_data_readahead(dp, next_ra, + XFS_DABUF_MAP_HOLE_OK); *ra_blk = next_ra; } ra_want -= geo->fsbcount; @@ -343,17 +347,17 @@ xfs_dir2_leaf_getdents( size_t bufsize) { struct xfs_inode *dp = args->dp; + struct xfs_mount *mp = dp->i_mount; struct xfs_buf *bp = NULL; /* data block buffer */ - xfs_dir2_data_hdr_t *hdr; /* data block header */ xfs_dir2_data_entry_t *dep; /* data entry */ xfs_dir2_data_unused_t *dup; /* unused entry */ - char *ptr = NULL; /* pointer to current data */ struct xfs_da_geometry *geo = args->geo; xfs_dablk_t rablk = 0; /* current readahead block */ xfs_dir2_off_t curoff; /* current overall offset */ int length; /* temporary length value */ int byteoff; /* offset in current block */ int lock_mode; + unsigned int offset = 0; int error = 0; /* error return value */ /* @@ -380,7 +384,7 @@ xfs_dir2_leaf_getdents( * If we have no buffer, or we're off the end of the * current buffer, need to get another one. */ - if (!bp || ptr >= (char *)bp->b_addr + geo->blksize) { + if (!bp || offset >= geo->blksize) { if (bp) { xfs_trans_brelse(args->trans, bp); bp = NULL; @@ -393,36 +397,35 @@ xfs_dir2_leaf_getdents( if (error || !bp) break; - hdr = bp->b_addr; xfs_dir3_data_check(dp, bp); /* * Find our position in the block. */ - ptr = (char *)dp->d_ops->data_entry_p(hdr); + offset = geo->data_entry_offset; byteoff = xfs_dir2_byte_to_off(geo, curoff); /* * Skip past the header. */ if (byteoff == 0) - curoff += dp->d_ops->data_entry_offset; + curoff += geo->data_entry_offset; /* * Skip past entries until we reach our offset. */ else { - while ((char *)ptr - (char *)hdr < byteoff) { - dup = (xfs_dir2_data_unused_t *)ptr; + while (offset < byteoff) { + dup = bp->b_addr + offset; if (be16_to_cpu(dup->freetag) == XFS_DIR2_DATA_FREE_TAG) { length = be16_to_cpu(dup->length); - ptr += length; + offset += length; continue; } - dep = (xfs_dir2_data_entry_t *)ptr; - length = - dp->d_ops->data_entsize(dep->namelen); - ptr += length; + dep = bp->b_addr + offset; + length = xfs_dir2_data_entsize(mp, + dep->namelen); + offset += length; } /* * Now set our real offset. @@ -430,32 +433,38 @@ xfs_dir2_leaf_getdents( curoff = xfs_dir2_db_off_to_byte(geo, xfs_dir2_byte_to_db(geo, curoff), - (char *)ptr - (char *)hdr); - if (ptr >= (char *)hdr + geo->blksize) { + offset); + if (offset >= geo->blksize) continue; - } } } + /* - * We have a pointer to an entry. - * Is it a live one? + * We have a pointer to an entry. Is it a live one? */ - dup = (xfs_dir2_data_unused_t *)ptr; + dup = bp->b_addr + offset; + /* * No, it's unused, skip over it. */ if (be16_to_cpu(dup->freetag) == XFS_DIR2_DATA_FREE_TAG) { length = be16_to_cpu(dup->length); - ptr += length; + offset += length; curoff += length; continue; } - dep = (xfs_dir2_data_entry_t *)ptr; - length = dp->d_ops->data_entsize(dep->namelen); - filetype = dp->d_ops->data_get_ftype(dep); + dep = bp->b_addr + offset; + length = xfs_dir2_data_entsize(mp, dep->namelen); + filetype = xfs_dir2_data_get_ftype(mp, dep); ctx->pos = xfs_dir2_byte_to_dataptr(curoff) & 0x7fffffff; + if (XFS_IS_CORRUPT(dp->i_mount, + !xfs_dir2_namecheck(dep->name, + dep->namelen))) { + error = -EFSCORRUPTED; + break; + } if (!dir_emit(ctx, (char *)dep->name, dep->namelen, be64_to_cpu(dep->inumber), xfs_dir3_get_dtype(dp->i_mount, filetype))) @@ -464,7 +473,7 @@ xfs_dir2_leaf_getdents( /* * Advance to next entry in the block. */ - ptr += length; + offset += length; curoff += length; /* bufsize may have just been a guess; don't go negative */ bufsize = bufsize > length ? bufsize - length : 0; |