From 655b09fe540b73edeaabfb4c2d700be51a1f8bce Mon Sep 17 00:00:00 2001 From: Josef Bacik Date: Fri, 17 May 2013 14:06:51 -0400 Subject: [PATCH] Btrfs: make sure roots are assigned before freeing their nodes If we fail to load the chunk tree we'll call free_root_pointers, except we may not have assigned the roots for the dev_root/extent_root/csum_root yet, so we could NULL pointer deref at this point. Just add checks to make sure these roots are set to keep us from panicing. Thanks, Signed-off-by: Josef Bacik --- fs/btrfs/disk-io.c | 39 +++++++++++++++++++++------------------ 1 file changed, 21 insertions(+), 18 deletions(-) diff --git a/fs/btrfs/disk-io.c b/fs/btrfs/disk-io.c index 1b03f83..4bdb052 100644 --- a/fs/btrfs/disk-io.c +++ b/fs/btrfs/disk-io.c @@ -1987,30 +1987,33 @@ static void free_root_pointers(struct btrfs_fs_info *info, int chunk_root) { free_extent_buffer(info->tree_root->node); free_extent_buffer(info->tree_root->commit_root); - free_extent_buffer(info->dev_root->node); - free_extent_buffer(info->dev_root->commit_root); - free_extent_buffer(info->extent_root->node); - free_extent_buffer(info->extent_root->commit_root); - free_extent_buffer(info->csum_root->node); - free_extent_buffer(info->csum_root->commit_root); - if (info->quota_root) { - free_extent_buffer(info->quota_root->node); - free_extent_buffer(info->quota_root->commit_root); - } - info->tree_root->node = NULL; info->tree_root->commit_root = NULL; - info->dev_root->node = NULL; - info->dev_root->commit_root = NULL; - info->extent_root->node = NULL; - info->extent_root->commit_root = NULL; - info->csum_root->node = NULL; - info->csum_root->commit_root = NULL; + + if (info->dev_root) { + free_extent_buffer(info->dev_root->node); + free_extent_buffer(info->dev_root->commit_root); + info->dev_root->node = NULL; + info->dev_root->commit_root = NULL; + } + if (info->extent_root) { + free_extent_buffer(info->extent_root->node); + free_extent_buffer(info->extent_root->commit_root); + info->extent_root->node = NULL; + info->extent_root->commit_root = NULL; + } + if (info->csum_root) { + free_extent_buffer(info->csum_root->node); + free_extent_buffer(info->csum_root->commit_root); + info->csum_root->node = NULL; + info->csum_root->commit_root = NULL; + } if (info->quota_root) { + free_extent_buffer(info->quota_root->node); + free_extent_buffer(info->quota_root->commit_root); info->quota_root->node = NULL; info->quota_root->commit_root = NULL; } - if (chunk_root) { free_extent_buffer(info->chunk_root->node); free_extent_buffer(info->chunk_root->commit_root); -- 2.7.4