lists  /  announce  owl-users  owl-dev  john-users  john-dev  passwdqc-users  yescrypt  popa3d-users  /  oss-security  kernel-hardening  musl  sabotage  tlsify  passwords  /  crypt-dev  xvendor  /  Bugtraq  Full-Disclosure  linux-kernel  linux-netdev  linux-ext4  linux-hardening  PHC 
Open Source and information security mailing list archives
Hash Suite: Windows password security audit tool. GUI, reports in PDF.
[<prev] [next>] [<thread-prev] [day] [month] [year] [list]
Date:	Mon, 9 Jul 2012 23:07:42 +0530
From:	Ashish Sangwan <>
To:	Lukáš Czerner <>
Cc:, Ted Tso <>,,,
	Namjae Jeon <>
Subject: Re: [PATCH v2] ext4: fix hole punch failure when depth is greater
 than 0

> Ok, the code is not very clear, but now I can see it. p_block is
> actually misused here to store the number of indexes in the current
> node while diving into the tree. Then on the way up, we are checking
> that to see if the eh_entries changed or not (which is indicating
> that something has been freed deeper in the tree).
True, p_block is misused. We tried to fix the problem with
minimum code change.
> That said, it makes sense to set it before the loop itself because
> we are actually skipping the path construction while diving into
> the tree since patch is already initialized and we're starting
> walking back from 'depth' up in this case. So the patch seems fine.
> Thanks for catching it and fixing it.
> You can add
> Reviewed-by: Lukas Czerner <>
Thanks for your review.
>> >
>> > Note: there are some indent problems in your patch, like for example
>> > this:
>> >
>> > +                       path[k].p_block =
>> > +                       le16_to_cpu(path[k].p_hdr->eh_entries)+1;
>> >
>> >
>> Before submitting the patch, I run with --strict option.
>> It did'nt show any error or warning. Should I re-submit
>> the patch with an extra tab before the second line? The call is yours.
> does not catch everything. Just look at how wrapping
> of long lines is done in the code, there are plenty of examples.
True again. I will resend patch with proper indentation.
>> > Anyway, what do you think about the modification ?
>> >
>> Also there is 1 modification missing from your patch.
>>     ext4_ext_drop_refs(path);
>>         kfree(path);
>> +       path = NULL;
>>         if (err == -EAGAIN)
>>                 goto again;
>> If path is not set to NULL, it will crash in xfstest #13. Ted has
>> already reported it.
> Right, I've probably used the old patch as an example.
> Thanks!
> -Lukas
To unsubscribe from this list: send the line "unsubscribe linux-ext4" in
the body of a message to
More majordomo info at

Powered by blists - more mailing lists