From 7e195bc5bfc5e82fdf735372a4773e6894676911 Mon Sep 17 00:00:00 2001 From: Forrest Liu Date: Mon, 17 Dec 2012 09:55:39 -0500 Subject: [PATCH] ext4: fix extent tree corruption caused by hole punch commit c36575e663e302dbaa4d16b9c72d2c9a913a9aef upstream. When depth of extent tree is greater than 1, logical start value of interior node is not correctly updated in ext4_ext_rm_idx. Signed-off-by: Forrest Liu Signed-off-by: "Theodore Ts'o" Reviewed-by: Ashish Sangwan Signed-off-by: Greg Kroah-Hartman --- fs/ext4/extents.c | 22 ++++++++++++++++++---- 1 file changed, 18 insertions(+), 4 deletions(-) diff --git a/fs/ext4/extents.c b/fs/ext4/extents.c index 7011ac967208e..19bb7691565c0 100644 --- a/fs/ext4/extents.c +++ b/fs/ext4/extents.c @@ -2190,13 +2190,14 @@ errout: * removes index from the index block. */ static int ext4_ext_rm_idx(handle_t *handle, struct inode *inode, - struct ext4_ext_path *path) + struct ext4_ext_path *path, int depth) { int err; ext4_fsblk_t leaf; /* free index block */ - path--; + depth--; + path = path + depth; leaf = ext4_idx_pblock(path->p_idx); if (unlikely(path->p_hdr->eh_entries == 0)) { EXT4_ERROR_INODE(inode, "path->p_hdr->eh_entries == 0"); @@ -2221,6 +2222,19 @@ static int ext4_ext_rm_idx(handle_t *handle, struct inode *inode, ext4_free_blocks(handle, inode, NULL, leaf, 1, EXT4_FREE_BLOCKS_METADATA | EXT4_FREE_BLOCKS_FORGET); + + while (--depth >= 0) { + if (path->p_idx != EXT_FIRST_INDEX(path->p_hdr)) + break; + path--; + err = ext4_ext_get_access(handle, inode, path); + if (err) + break; + path->p_idx->ei_block = (path+1)->p_idx->ei_block; + err = ext4_ext_dirty(handle, inode, path); + if (err) + break; + } return err; } @@ -2557,7 +2571,7 @@ ext4_ext_rm_leaf(handle_t *handle, struct inode *inode, /* if this leaf is free, then we should * remove it from index block above */ if (err == 0 && eh->eh_entries == 0 && path[depth].p_bh != NULL) - err = ext4_ext_rm_idx(handle, inode, path + depth); + err = ext4_ext_rm_idx(handle, inode, path, depth); out: return err; @@ -2760,7 +2774,7 @@ again: /* index is empty, remove it; * handle must be already prepared by the * truncatei_leaf() */ - err = ext4_ext_rm_idx(handle, inode, path + i); + err = ext4_ext_rm_idx(handle, inode, path, i); } /* root level has p_bh == NULL, brelse() eats this */ brelse(path[i].p_bh); -- 2.47.3