From: Eryu Guan <guan@eryu.me>
To: Boris Burkov <boris@bur.io>
Cc: fstests@vger.kernel.org, linux-fscrypt@vger.kernel.org,
linux-btrfs@vger.kernel.org, kernel-team@fb.com
Subject: Re: [PATCH v3 2/3] generic/574: corrupt btrfs merkle tree data
Date: Sun, 11 Apr 2021 20:19:32 +0800 [thread overview]
Message-ID: <YHLpVNiPVXVPM1oP@desktop> (raw)
In-Reply-To: <4429f6365c3250efe9bf7bc0a1a22e642b149f61.1617908086.git.boris@bur.io>
On Thu, Apr 08, 2021 at 11:57:50AM -0700, Boris Burkov wrote:
> generic/574 has tests for corrupting the merkle tree data stored by the
> filesystem. Since btrfs uses a different scheme for storing this data,
> the existing logic for corrupting it doesn't work out of the box. Adapt
> it to properly corrupt btrfs merkle items.
>
> Note that there is a bit of a kludge here: since btrfs_corrupt_block
> doesn't handle streaming corruption bytes from stdin (I could change
> that, but it feels like overkill for this purpose), I just read the
> first corruption byte and duplicate it for the desired length. That is
> how the test is using the interface in practice, anyway.
>
> This relies on the following kernel patch for btrfs verity support:
> <btrfs-verity-patch>
> And the following btrfs-progs patch for btrfs_corrupt_block support:
> <btrfs-corrupt-block-patch>
>
> Signed-off-by: Boris Burkov <boris@bur.io>
> ---
> common/verity | 15 +++++++++++++--
> 1 file changed, 13 insertions(+), 2 deletions(-)
>
> diff --git a/common/verity b/common/verity
> index d2c1ea24..fdd05783 100644
> --- a/common/verity
> +++ b/common/verity
> @@ -3,8 +3,7 @@
> #
> # Functions for setting up and testing fs-verity
>
> -_require_scratch_verity()
> -{
> +_require_scratch_verity() {
No need to change this.
> _require_scratch
> _require_command "$FSVERITY_PROG" fsverity
>
> @@ -315,6 +314,18 @@ _fsv_scratch_corrupt_merkle_tree()
> (( offset += ($(_get_filesize $file) + 65535) & ~65535 ))
> _fsv_scratch_corrupt_bytes $file $offset
> ;;
> + btrfs)
> + ino=$(ls -i $file | awk '{print $1}')
stat -c %i $1
And declare local variables with local.
> + sync
Why a system wide sync is needed here?
> + cat > $tmp.bytes
I think this cat would just hang there.
> + sz=$(_get_filesize $tmp.bytes)
> + read -n 1 byte < $tmp.bytes
> + ascii=$(printf "%d" "'$byte'")
> + _scratch_unmount
> + $BTRFS_CORRUPT_BLOCK_PROG -r 5 -I $ino,37,0 -v $ascii -o $offset -b $sz $SCRATCH_DEV
It'd be better to explain this command in comments.
> + sync
Again, is this sync really needed?
Thanks,
Eryu
> + _scratch_mount
> + ;;
> *)
> _fail "_fsv_scratch_corrupt_merkle_tree() unimplemented on $FSTYP"
> ;;
> --
> 2.30.2
next prev parent reply other threads:[~2021-04-11 12:19 UTC|newest]
Thread overview: 7+ messages / expand[flat|nested] mbox.gz Atom feed top
2021-04-08 18:57 [PATCH v3 0/3] tests for btrfs fsverity Boris Burkov
2021-04-08 18:57 ` [PATCH v3 1/3] btrfs: test btrfs specific fsverity corruption Boris Burkov
2021-04-08 23:11 ` Eric Biggers
2021-04-11 12:13 ` Eryu Guan
2021-04-08 18:57 ` [PATCH v3 2/3] generic/574: corrupt btrfs merkle tree data Boris Burkov
2021-04-11 12:19 ` Eryu Guan [this message]
2021-04-08 18:57 ` [PATCH v3 3/3] btrfs: test verity orphans with dmlogwrites Boris Burkov
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=YHLpVNiPVXVPM1oP@desktop \
--to=guan@eryu.me \
--cc=boris@bur.io \
--cc=fstests@vger.kernel.org \
--cc=kernel-team@fb.com \
--cc=linux-btrfs@vger.kernel.org \
--cc=linux-fscrypt@vger.kernel.org \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).