Re: [PATCH]An inlinedata bug in ext4_destroy_inline_data_nolock()

[Tao Ma <tm@tao.ma>]

On 10/08/2013 11:32 PM, baixing quan wrote:
> Filesystem with inlinedata will be remounted with read only mode as
> follow steps:
> 
> 1.mkdir tmp
> 2.cd tmp
> 3.mkdir a12345 a23456 a34567 a45678 a67890 a78901
> 4.reboot
> 5.cd tmp
> 6.mv a23456 a23456aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa
> 
> The bug happened in ext4_rename()
> 3122         if (le32_to_cpu(old_de->inode) != old_inode->i_ino ||
> 3123             old_de->name_len != old_dentry->d_name.len ||
> 3124             strncmp(old_de->name, old_dentry->d_name.name,
> old_de->name_len) ||
> 3125             (retval = ext4_delete_entry(handle, old_dir,
> 3126                                         old_de, old_bh)) == -ENOENT)
> 
> ext4_delete_entry-> ext4_generic_delete_entry-> ext4_check_dir_entry()
>  find the inode number is illegal and the system is remounted with
> read only mode.
> 
> When the inlinedata is cleared in
> ext4_destroy_inline_data_nolock(),ext4_inode->i_block[] is set to 0,
> but ext4_inode->i_block[] is assigned as ext4_inode_info->i_block[] in
> ext4_mark_iloc_dirty().Therefore, the inlinedata still exist in
> ext4_inode->i_block[] and result in ext4_delete_entry() in line 3125
> is executed.
oh, thanks for the detailed explanation, soo the patch looks good to me.
But would you mind try what Darrick suggest? A good reference book
should be Documentation/SubmittingPatches.

Thanks,
Tao
> 
> 
> From d0e24fc2c0817fafe816b510060c711e56b6b645 Mon Sep 17 00:00:00 2001
> From: qbx <quanbaixin@126.com>
> Date: Tue, 8 Oct 2013 07:04:13 -0700
> Subject: [PATCH] inlinedata rename bug
> 
> ---
>  fs/ext4/inline.c |    1 +
>  1 file changed, 1 insertion(+)
> 
> diff --git a/fs/ext4/inline.c b/fs/ext4/inline.c
> index d9ecbf1..cc6375e 100644
> --- a/fs/ext4/inline.c
> +++ b/fs/ext4/inline.c
> @@ -434,6 +434,7 @@ static int ext4_destroy_inline_data_nolock(handle_t *handle,
> 
>         memset((void *)ext4_raw_inode(&is.iloc)->i_block,
>                 0, EXT4_MIN_INLINE_DATA_SIZE);
> +       memset(ei->i_data,0, sizeof(ei->i_data));
> 
>         if (EXT4_HAS_INCOMPAT_FEATURE(inode->i_sb,
>                                       EXT4_FEATURE_INCOMPAT_EXTENTS)) {
>