Re: [PATCH] jbd: correctly unescape journal data blocks

[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

 



> Fix a long-standing typo (predating git) that will cause data corruption if a
> journal data block needs unescaping. At the moment the wrong buffer head's data
> is being unescaped.
> 
> To test this case mount a filesystem with data=journal, start creating and
> deleting a bunch of files containing only JFS_MAGIC_NUMBER (0xc03b3998), then
> pull the plug on the device. Without this patch the files will contain zeros
> instead of the correct data after recovery.
> 
> Signed-off-by: Duane Griffin <duaneg@xxxxxxxxx>
> ---
>  fs/jbd/recovery.c |    2 +-
>  1 files changed, 1 insertions(+), 1 deletions(-)
> 
> diff --git a/fs/jbd/recovery.c b/fs/jbd/recovery.c
> index 2b8edf4..43bc5e5 100644
> --- a/fs/jbd/recovery.c
> +++ b/fs/jbd/recovery.c
> @@ -478,7 +478,7 @@ static int do_one_pass(journal_t *journal,
>  					memcpy(nbh->b_data, obh->b_data,
>  							journal->j_blocksize);
>  					if (flags & JFS_FLAG_ESCAPE) {
> -						*((__be32 *)bh->b_data) =
> +						*((__be32 *)nbh->b_data) =
>  						cpu_to_be32(JFS_MAGIC_NUMBER);
>  					}
  Good catch. Acked-by: Jan Kara <jack@xxxxxxx>

										Honza

-- 
Jan Kara <jack@xxxxxxx>
SuSE CR Labs
--
To unsubscribe from this list: send the line "unsubscribe linux-ext4" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at  http://vger.kernel.org/majordomo-info.html

[Index of Archives]     [Reiser Filesystem Development]     [Ceph FS]     [Kernel Newbies]     [Security]     [Netfilter]     [Bugtraq]     [Linux FS]     [Yosemite National Park]     [MIPS Linux]     [ARM Linux]     [Linux Security]     [Linux RAID]     [Samba]     [Device Mapper]     [Linux Media]

  Powered by Linux