From b4df2030858bde986cb6ff2e4b45945f84649e32 Mon Sep 17 00:00:00 2001 From: Theodore Ts'o <tytso@mit.edu> Date: Wed, 13 Aug 2008 21:44:34 -0400 Subject: [PATCH] ext4: Fix potential truncate BUG due to i_prealloc_list being non-empty We need to call ext4_discard_reservation() earlier in ext4_truncate(), to avoid a BUG() in ext4_mb_return_to_preallocation(), which is called (ultimately) by ext4_free_blocks(). So we must ditch the blocks on i_prealloc_list before we start freeing the data blocks. Signed-off-by: "Theodore Ts'o" <tytso@mit.edu> --- fs/ext4/inode.c | 5 +++-- 1 file changed, 3 insertions(+), 2 deletions(-) diff --git a/fs/ext4/inode.c b/fs/ext4/inode.c index a1c7d7623213..2d54c822c4c3 100644 --- a/fs/ext4/inode.c +++ b/fs/ext4/inode.c @@ -3494,6 +3494,9 @@ void ext4_truncate(struct inode *inode) * modify the block allocation tree. */ down_write(&ei->i_data_sem); + + ext4_discard_reservation(inode); + /* * The orphan list entry will now protect us from any crash which * occurs before the truncate completes, so it is now safe to propagate @@ -3563,8 +3566,6 @@ do_indirects: ; } - ext4_discard_reservation(inode); - up_write(&ei->i_data_sem); inode->i_mtime = inode->i_ctime = ext4_current_time(inode); ext4_mark_inode_dirty(handle, inode); -- 2.34.1