Hi Changwei,
Sorry for the oversight for your patch. There is nothing wrong.
Thanks,
Jun
On 2018/11/10 15:58, Changwei Ge wrote:
> Hi Jun,
>
> Thanks for looking into this, my code from Linux mainline is not looked like yours...
>
> On 2018/11/10 14:36, piaojun wrote:
>> Hi Changwei,
>>
>> On 2018/5/28 22:40, Changwei Ge wrote:
>>> From: Changwei Ge <ge.changwei@xxxxxxx>
>>>
>>> Somehow, file system metadata was corrupted, which causes
>>> ocfs2_check_dir_entry() to fail in function ocfs2_dir_foreach_blk_el().
>>>
>>> According to the original design intention, if above happens we should
>>> skip the problematic block and continue to retrieve dir entry. But there
>>> is obviouse misuse of brelse around related code.
>>>
>>> After failure of ocfs2_check_dir_entry(), currunt code just moves to next
>>> position and uses the problematic buffer head again and again during
>>> which the problematic buffer head is released for multiple times. I
>>> suppose, this a serious issue which is long-lived in ocfs2. This may
>>> cause other file systems which is also used in a the same host insane.
>>>
>>> So we should also consider about bakcporting this patch into
>>> linux -stable.
>>>
>>> Suggested-by: Changkuo Shi <shi.changkuo@xxxxxxx>
>>> Cc: stable@xxxxxxxxxxxxxxx
>>> Signed-off-by: Changwei Ge <ge.changwei@xxxxxxx>
>>> ---
>>> fs/ocfs2/dir.c | 3 +--
>>> 1 file changed, 1 insertion(+), 2 deletions(-)
>>>
>>> diff --git a/fs/ocfs2/dir.c b/fs/ocfs2/dir.c
>>> index b048d4f..c121abb 100644
>>> --- a/fs/ocfs2/dir.c
>>> +++ b/fs/ocfs2/dir.c
>>> @@ -1897,8 +1897,7 @@ static int ocfs2_dir_foreach_blk_el(struct inode *inode,
>>> /* On error, skip the f_pos to the
>>> next block. */
>>> ctx->pos = (ctx->pos | (sb->s_blocksize - 1)) + 1;
>>> - brelse(bh);
>>> - continue;
>>> + break;
>>
>> I guess return is more appropriate than break here as it will cause double
>> free buffer:
>>
>> "
>> ctx->pos = (ctx->pos | (sb->s_blocksize - 1)) + 1;
>> brelse(bh);
>> break;
>> "
>
> Linux mainline should not have 'brelse(bh)', could your please rebase your tree?
>
> '''
> ccd979bdb (Mark Fasheh 2005-12-15 14:31:24 -0800 1897) /* On error, skip the f_pos to the
> ccd979bdb (Mark Fasheh 2005-12-15 14:31:24 -0800 1898) next block. */
> 3704412bd (Al Viro 2013-05-22 21:06:00 -0400 1899) ctx->pos = (ctx->pos | (sb->s_blocksize - 1)) + 1;
> 29aa30167 (Changwei Ge 2018-11-02 15:48:15 -0700 1900) break;
> '''
>>
>> "
>> brelse(bh);
>> bh = NULL;
>> if (!persist && stored)
>> break;
>> "
>>
>> Thanks,
>> Jun
>>
>>> }
>>> if (le64_to_cpu(de->inode)) {
>>> unsigned char d_type = DT_UNKNOWN;
>>>
>>
>> _______________________________________________
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>> Ocfs2-devel@xxxxxxxxxxxxxx
>> https://oss.oracle.com/mailman/listinfo/ocfs2-devel
>>
> .
>
