From c36575e663e302dbaa4d16b9c72d2c9a913a9aef 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 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 Cc: stable@vger.kernel.org --- 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 26af22832a84..5ae1674ec12f 100644 --- a/fs/ext4/extents.c +++ b/fs/ext4/extents.c @@ -2226,13 +2226,14 @@ 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"); @@ -2257,6 +2258,19 @@ 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; } @@ -2599,7 +2613,7 @@ 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; @@ -2802,7 +2816,7 @@ 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); -- 2.30.2