diff options
| -rw-r--r-- | fs/gfs2/dir.c | 35 |
1 files changed, 30 insertions, 5 deletions
diff --git a/fs/gfs2/dir.c b/fs/gfs2/dir.c index 82a1ac7895a2..6c3ed7674a9f 100644 --- a/fs/gfs2/dir.c +++ b/fs/gfs2/dir.c @@ -1262,9 +1262,10 @@ static int gfs2_dir_read_leaf(struct inode *inode, u64 *offset, void *opaque, u64 leaf_no) { struct gfs2_inode *ip = GFS2_I(inode); + struct gfs2_sbd *sdp = GFS2_SB(inode); struct buffer_head *bh; struct gfs2_leaf *lf; - unsigned entries = 0; + unsigned entries = 0, entries2 = 0; unsigned leaves = 0; const struct gfs2_dirent **darr, *dent; struct dirent_gather g; @@ -1290,7 +1291,13 @@ static int gfs2_dir_read_leaf(struct inode *inode, u64 *offset, void *opaque, return 0; error = -ENOMEM; - larr = vmalloc((leaves + entries) * sizeof(void *)); + /* + * The extra 99 entries are not normally used, but are a buffer + * zone in case the number of entries in the leaf is corrupt. + * 99 is the maximum number of entries that can fit in a single + * leaf block. + */ + larr = vmalloc((leaves + entries + 99) * sizeof(void *)); if (!larr) goto out; darr = (const struct gfs2_dirent **)(larr + leaves); @@ -1305,10 +1312,18 @@ static int gfs2_dir_read_leaf(struct inode *inode, u64 *offset, void *opaque, lf = (struct gfs2_leaf *)bh->b_data; lfn = be64_to_cpu(lf->lf_next); if (lf->lf_entries) { + entries2 += be16_to_cpu(lf->lf_entries); dent = gfs2_dirent_scan(inode, bh->b_data, bh->b_size, gfs2_dirent_gather, NULL, &g); error = PTR_ERR(dent); - if (IS_ERR(dent)) { + if (IS_ERR(dent)) + goto out_kfree; + if (entries2 != g.offset) { + fs_warn(sdp, "Number of entries corrupt in dir leaf %llu, " + "entries2 (%u) != g.offset (%u)\n", + (u64)bh->b_blocknr, entries2, g.offset); + + error = -EIO; goto out_kfree; } error = 0; @@ -1318,6 +1333,7 @@ static int gfs2_dir_read_leaf(struct inode *inode, u64 *offset, void *opaque, } } while(lfn); + BUG_ON(entries2 != entries); error = do_filldir_main(ip, offset, opaque, filldir, darr, entries, copied); out_kfree: @@ -1401,6 +1417,7 @@ int gfs2_dir_read(struct inode *inode, u64 *offset, void *opaque, filldir_t filldir) { struct gfs2_inode *dip = GFS2_I(inode); + struct gfs2_sbd *sdp = GFS2_SB(inode); struct dirent_gather g; const struct gfs2_dirent **darr, *dent; struct buffer_head *dibh; @@ -1423,8 +1440,8 @@ int gfs2_dir_read(struct inode *inode, u64 *offset, void *opaque, return error; error = -ENOMEM; - darr = kmalloc(dip->i_di.di_entries * sizeof(struct gfs2_dirent *), - GFP_KERNEL); + /* 96 is max number of dirents which can be stuffed into an inode */ + darr = kmalloc(96 * sizeof(struct gfs2_dirent *), GFP_KERNEL); if (darr) { g.pdent = darr; g.offset = 0; @@ -1434,6 +1451,14 @@ int gfs2_dir_read(struct inode *inode, u64 *offset, void *opaque, error = PTR_ERR(dent); goto out; } + if (dip->i_di.di_entries != g.offset) { + fs_warn(sdp, "Number of entries corrupt in dir %llu, " + "ip->i_di.di_entries (%u) != g.offset (%u)\n", + dip->i_num.no_addr, dip->i_di.di_entries, + g.offset); + error = -EIO; + goto out; + } error = do_filldir_main(dip, offset, opaque, filldir, darr, dip->i_di.di_entries, &copied); out: |