[PATCH] common/filter: add _filter_bash()

[PATCH] common/filter: add _filter_bash()

[Theodore Ts'o]

This is needed to account for bash 5.1 adding line number annotation
when a command like "bash -c /etc/passwd" fails, e.g., with

     bash: line 1: /etc/passwd: Permission denied

instead of:

     bash: /etc/passwd: Permission denied

Signed-off-by: Theodore Ts'o <tytso@mit.edu>
---
 common/filter     | 11 +++++++++++
 tests/generic/572 | 33 +++++++++++++++++++--------------
 2 files changed, 30 insertions(+), 14 deletions(-)

diff --git a/common/filter b/common/filter
index 2efbbd99..4b250e8b 100644
--- a/common/filter
+++ b/common/filter
@@ -661,5 +661,16 @@ _filter_quota_report()
 		s|^(.*?) (\d+) (\d+) (\d+)|$1 @{[$2 * 1024 /'$bsize']} @{[$3 * 1024 /'$bsize']} @{[$4 * 1024 /'$bsize']}|'
 }
 
+#
+# Bash 5.1+ adds "line 1: " when printing an error running an executable
+# for example, "bash -c /etc/passwd" will result in the error
+# "bash: line 1: /etc/passwd: Permission denied" where as earlier
+# versions of bash will omit the "line 1: " annotation.
+#
+_filter_bash()
+{
+	sed -e "s/^bash: line 1: /bash: /"
+}
+
 # make sure this script returns success
 /bin/true
diff --git a/tests/generic/572 b/tests/generic/572
index f131c7ed..cded9ac6 100755
--- a/tests/generic/572
+++ b/tests/generic/572
@@ -36,6 +36,11 @@ _scratch_mount
 fsv_orig_file=$SCRATCH_MNT/file
 fsv_file=$SCRATCH_MNT/file.fsv
 
+filter_output()
+{
+    _filter_bash | _filter_scratch
+}
+
 verify_data_readable()
 {
 	local file=$1
@@ -48,41 +53,41 @@ verify_data_unreadable()
 	local file=$1
 
 	# try both reading just the first data block, and reading until EOF
-	head -c $FSV_BLOCK_SIZE $file 2>&1 >/dev/null | _filter_scratch
-	md5sum $file |& _filter_scratch
+	head -c $FSV_BLOCK_SIZE $file 2>&1 >/dev/null | filter_output
+	md5sum $file |& filter_output
 }
 
 _fsv_scratch_begin_subtest "Enabling verity on file with verity already enabled fails with EEXIST"
 _fsv_create_enable_file $fsv_file
 echo "(trying again)"
-_fsv_enable $fsv_file |& _filter_scratch
+_fsv_enable $fsv_file |& filter_output
 
 _fsv_scratch_begin_subtest "Enabling verity with invalid hash algorithm fails with EINVAL"
-_fsv_create_enable_file $fsv_file --hash-alg=257 |& _filter_scratch
+_fsv_create_enable_file $fsv_file --hash-alg=257 |& filter_output
 verify_data_readable $fsv_file
 
 _fsv_scratch_begin_subtest "Enabling verity with invalid block size fails with EINVAL"
-_fsv_create_enable_file $fsv_file --block-size=1 |& _filter_scratch
+_fsv_create_enable_file $fsv_file --block-size=1 |& filter_output
 verify_data_readable $fsv_file
 
 _fsv_scratch_begin_subtest "Enabling verity on directory fails with EISDIR"
 mkdir $SCRATCH_MNT/dir
-_fsv_enable $SCRATCH_MNT/dir |& _filter_scratch
+_fsv_enable $SCRATCH_MNT/dir |& filter_output
 
 _fsv_scratch_begin_subtest "Enabling verity with too-long salt fails with EMSGSIZE"
-_fsv_create_enable_file $fsv_file --salt=$(perl -e 'print "A" x 1000') |& _filter_scratch
+_fsv_create_enable_file $fsv_file --salt=$(perl -e 'print "A" x 1000') |& filter_output
 verify_data_readable $fsv_file
 
 _fsv_scratch_begin_subtest "Enabling verity on file on read-only filesystem fails with EROFS"
 echo foo > $fsv_file
 _scratch_remount ro
-_fsv_enable $fsv_file |& _filter_scratch
+_fsv_enable $fsv_file |& filter_output
 _scratch_remount rw
 
 _fsv_scratch_begin_subtest "Enabling verity on file open for writing fails with ETXTBSY"
 echo foo > $fsv_file
 exec 3<> $fsv_file
-_fsv_enable $fsv_file |& _filter_scratch
+_fsv_enable $fsv_file |& filter_output
 exec 3<&-
 verify_data_readable $fsv_file
 
@@ -103,7 +108,7 @@ dd if=/dev/zero of=$fsv_file bs=1 count=0 seek=$((1 << 34)) status=none
 start_time=$(date +%s)
 $FSVERITY_PROG enable $fsv_file &
 sleep 0.5
-_fsv_enable $fsv_file |& _filter_scratch
+_fsv_enable $fsv_file |& filter_output
 kill %1
 wait
 
@@ -112,11 +117,11 @@ _fsv_create_enable_file $fsv_file >> $seqres.full
 echo "* reading"
 $XFS_IO_PROG -r $fsv_file -c ''
 echo "* xfs_io writing, should be O_RDWR"
-$XFS_IO_PROG $fsv_file -c '' |& _filter_scratch
+$XFS_IO_PROG $fsv_file -c '' |& filter_output
 echo "* bash >>, should be O_APPEND"
-bash -c "echo >> $fsv_file" |& _filter_scratch
+bash -c "echo >> $fsv_file" |& filter_output
 echo "* bash >, should be O_WRONLY|O_CREAT|O_TRUNC"
-bash -c "echo > $fsv_file" |& _filter_scratch
+bash -c "echo > $fsv_file" |& filter_output
 
 _fsv_scratch_begin_subtest "verity file can be read"
 _fsv_create_enable_file $fsv_file >> $seqres.full
@@ -160,7 +165,7 @@ _get_filesize $fsv_file
 
 _fsv_scratch_begin_subtest "Trying to measure non-verity file fails with ENODATA"
 echo foo > $fsv_file
-_fsv_measure $fsv_file |& _filter_scratch
+_fsv_measure $fsv_file |& filter_output
 verify_data_readable $fsv_file
 
 # Test files <= 1 block in size.  These are a bit of a special case since there
-- 
2.31.0

Re: [PATCH] common/filter: add _filter_bash()

[Eric Biggers]

Hi Ted,

On Tue, Dec 14, 2021 at 12:04:38PM -0500, Theodore Ts'o wrote:
> This is needed to account for bash 5.1 adding line number annotation
> when a command like "bash -c /etc/passwd" fails, e.g., with
> 
>      bash: line 1: /etc/passwd: Permission denied
> 
> instead of:
> 
>      bash: /etc/passwd: Permission denied
> 
> Signed-off-by: Theodore Ts'o <tytso@mit.edu>
> ---
>  common/filter     | 11 +++++++++++
>  tests/generic/572 | 33 +++++++++++++++++++--------------
>  2 files changed, 30 insertions(+), 14 deletions(-)
> 
> diff --git a/common/filter b/common/filter
> index 2efbbd99..4b250e8b 100644
> --- a/common/filter
> +++ b/common/filter
> @@ -661,5 +661,16 @@ _filter_quota_report()
>  		s|^(.*?) (\d+) (\d+) (\d+)|$1 @{[$2 * 1024 /'$bsize']} @{[$3 * 1024 /'$bsize']} @{[$4 * 1024 /'$bsize']}|'
>  }
>  
> +#
> +# Bash 5.1+ adds "line 1: " when printing an error running an executable
> +# for example, "bash -c /etc/passwd" will result in the error
> +# "bash: line 1: /etc/passwd: Permission denied" where as earlier
> +# versions of bash will omit the "line 1: " annotation.
> +#
> +_filter_bash()
> +{
> +	sed -e "s/^bash: line 1: /bash: /"
> +}
> +

Doesn't this happen with any shell command passed to -c, not just commands that
run an executable?  In the commands below which are causing the problem, it is
actually the 'echo' built-in being used, not an executable.

> -bash -c "echo >> $fsv_file" |& _filter_scratch
> +bash -c "echo >> $fsv_file" |& filter_output
>  echo "* bash >, should be O_WRONLY|O_CREAT|O_TRUNC"
> -bash -c "echo > $fsv_file" |& _filter_scratch
> +bash -c "echo > $fsv_file" |& filter_output

Otherwise this patch looks good, thanks!

- Eric

Re: [PATCH] common/filter: add _filter_bash()

[Theodore Ts'o]

On Wed, Dec 15, 2021 at 04:54:19PM -0800, Eric Biggers wrote:
> 
> Doesn't this happen with any shell command passed to -c, not just commands that
> run an executable?  In the commands below which are causing the problem, it is
> actually the 'echo' built-in being used, not an executable.

Well.... it happens with all executables and *some* built-in commands
which returns an error.  (See the postscript for a case where the line
number is printed.)  In the case of an error opening the redirected
standard output, such as permission denied, the difference does occur:

Compare:

% schroot -c buster-amd64 -- bash -c "echo foo >> /bin/bash"
bash: /bin/bash: Permission denied
% schroot -c buster-amd64 -- bash --version
GNU bash, version 5.0.3(1)-release (x86_64-pc-linux-gnu)
Copyright (C) 2019 Free Software Foundation, Inc.
...

with

% schroot -c bullseye-amd64 -- bash -c "echo foo >> /bin/bash"
bash: line 1: /bin/bash: Permission denied
% schroot -c bullseye-amd64 -- bash --version
GNU bash, version 5.1.4(1)-release (x86_64-pc-linux-gnu)
...

I just used the example of "bash -c /etc/passwd" because it was
simpler, and because it would be easy to verify regardless of whether
the command was executed as root or not.  For example:

% schroot -c bullseye-amd64 -u root -- bash -c "echo foo >> /bin/bash"

would have succeeded (and corrupted /bin/bash in my chroot :-).

I suppose I could have used the "schroot -c ..." example in the commit
description, but that's a debian-specific command, and I chose to err
on the side of something simpler and easier to replicate.

If Eryu would prefer, I can resend with a modified commit description,
or he can feel free to edit the commit description with the above
example if he thinks it's clearer.

Cheers,

				- Ted

P.S. The 5.1 behavior is actually a bit more consistent, since other
errors involving built-ins do actualy print a line number (although
not a *consistent* line number between bash 5.0 and 5.1:

% schroot -c buster-amd64 -- bash -c "jobs --bad-option"
bash: line 0: jobs: --: invalid option
...

vs

% schroot -c bullseye-amd64 -- bash -c "jobs --bad-option"
bash: line 1: jobs: --: invalid option
...

So the changes in Bash 5.1 error reporting does have something to
recommend itself in terms of self-consistency, but it is a bit of pain
for xfstests, where any changes in output requires extra filter
hacking!

Re: [PATCH] common/filter: add _filter_bash()

[Eric Biggers]

On Sat, Dec 18, 2021 at 12:10:20PM -0500, Theodore Ts'o wrote:
> On Wed, Dec 15, 2021 at 04:54:19PM -0800, Eric Biggers wrote:
> > 
> > Doesn't this happen with any shell command passed to -c, not just commands that
> > run an executable?  In the commands below which are causing the problem, it is
> > actually the 'echo' built-in being used, not an executable.
> 
> Well.... it happens with all executables and *some* built-in commands
> which returns an error.  (See the postscript for a case where the line
> number is printed.)  In the case of an error opening the redirected
> standard output, such as permission denied, the difference does occur:
> 
> Compare:
> 
> % schroot -c buster-amd64 -- bash -c "echo foo >> /bin/bash"
> bash: /bin/bash: Permission denied
> % schroot -c buster-amd64 -- bash --version
> GNU bash, version 5.0.3(1)-release (x86_64-pc-linux-gnu)
> Copyright (C) 2019 Free Software Foundation, Inc.
> ...
> 
> with
> 
> % schroot -c bullseye-amd64 -- bash -c "echo foo >> /bin/bash"
> bash: line 1: /bin/bash: Permission denied
> % schroot -c bullseye-amd64 -- bash --version
> GNU bash, version 5.1.4(1)-release (x86_64-pc-linux-gnu)
> ...
> 
> I just used the example of "bash -c /etc/passwd" because it was
> simpler, and because it would be easy to verify regardless of whether
> the command was executed as root or not.  For example:
> 
> % schroot -c bullseye-amd64 -u root -- bash -c "echo foo >> /bin/bash"
> 
> would have succeeded (and corrupted /bin/bash in my chroot :-).

A good example that doesn't involve an executable would be

	bash -c "echo foo > /"

... since that command redirection will always fail.

> I suppose I could have used the "schroot -c ..." example in the commit
> description, but that's a debian-specific command, and I chose to err
> on the side of something simpler and easier to replicate.
> 
> If Eryu would prefer, I can resend with a modified commit description,
> or he can feel free to edit the commit description with the above
> example if he thinks it's clearer.

I'm more concerned about the misleading comment above _filter_bash(), not the
commit message which is less important.  Anyway, it's not too important, but I
thought it was worth pointing out.

- Eric

[PATCH -v2] common/filter: add _filter_bash()

[Theodore Ts'o]

This is needed to account for bash 5.1 adding line number annotation
when executing a command via the -c option and it fails.  For example,
"bash -c 'echo foo > /'" will cause bash 5.1 to report:

     bash: line 1: /: Is a directory

instead of:

     bash: /: Is a directory

Signed-off-by: Theodore Ts'o <tytso@mit.edu>
---
 common/filter     | 11 +++++++++++
 tests/generic/572 | 33 +++++++++++++++++++--------------
 2 files changed, 30 insertions(+), 14 deletions(-)

diff --git a/common/filter b/common/filter
index 2efbbd99..c3db7a56 100644
--- a/common/filter
+++ b/common/filter
@@ -661,5 +661,16 @@ _filter_quota_report()
 		s|^(.*?) (\d+) (\d+) (\d+)|$1 @{[$2 * 1024 /'$bsize']} @{[$3 * 1024 /'$bsize']} @{[$4 * 1024 /'$bsize']}|'
 }
 
+#
+# Bash 5.1+ adds "line 1: " when reporting an error when running a
+# command via the -c option.  For example, "bash -c 'echo foo > /'"
+# will result in the error "bash: line 1: /: Is a directory" when
+# earlier versions of bash would omit the "line 1: " annotation.
+#
+_filter_bash()
+{
+	sed -e "s/^bash: line 1: /bash: /"
+}
+
 # make sure this script returns success
 /bin/true
diff --git a/tests/generic/572 b/tests/generic/572
index f131c7ed..cded9ac6 100755
--- a/tests/generic/572
+++ b/tests/generic/572
@@ -36,6 +36,11 @@ _scratch_mount
 fsv_orig_file=$SCRATCH_MNT/file
 fsv_file=$SCRATCH_MNT/file.fsv
 
+filter_output()
+{
+    _filter_bash | _filter_scratch
+}
+
 verify_data_readable()
 {
 	local file=$1
@@ -48,41 +53,41 @@ verify_data_unreadable()
 	local file=$1
 
 	# try both reading just the first data block, and reading until EOF
-	head -c $FSV_BLOCK_SIZE $file 2>&1 >/dev/null | _filter_scratch
-	md5sum $file |& _filter_scratch
+	head -c $FSV_BLOCK_SIZE $file 2>&1 >/dev/null | filter_output
+	md5sum $file |& filter_output
 }
 
 _fsv_scratch_begin_subtest "Enabling verity on file with verity already enabled fails with EEXIST"
 _fsv_create_enable_file $fsv_file
 echo "(trying again)"
-_fsv_enable $fsv_file |& _filter_scratch
+_fsv_enable $fsv_file |& filter_output
 
 _fsv_scratch_begin_subtest "Enabling verity with invalid hash algorithm fails with EINVAL"
-_fsv_create_enable_file $fsv_file --hash-alg=257 |& _filter_scratch
+_fsv_create_enable_file $fsv_file --hash-alg=257 |& filter_output
 verify_data_readable $fsv_file
 
 _fsv_scratch_begin_subtest "Enabling verity with invalid block size fails with EINVAL"
-_fsv_create_enable_file $fsv_file --block-size=1 |& _filter_scratch
+_fsv_create_enable_file $fsv_file --block-size=1 |& filter_output
 verify_data_readable $fsv_file
 
 _fsv_scratch_begin_subtest "Enabling verity on directory fails with EISDIR"
 mkdir $SCRATCH_MNT/dir
-_fsv_enable $SCRATCH_MNT/dir |& _filter_scratch
+_fsv_enable $SCRATCH_MNT/dir |& filter_output
 
 _fsv_scratch_begin_subtest "Enabling verity with too-long salt fails with EMSGSIZE"
-_fsv_create_enable_file $fsv_file --salt=$(perl -e 'print "A" x 1000') |& _filter_scratch
+_fsv_create_enable_file $fsv_file --salt=$(perl -e 'print "A" x 1000') |& filter_output
 verify_data_readable $fsv_file
 
 _fsv_scratch_begin_subtest "Enabling verity on file on read-only filesystem fails with EROFS"
 echo foo > $fsv_file
 _scratch_remount ro
-_fsv_enable $fsv_file |& _filter_scratch
+_fsv_enable $fsv_file |& filter_output
 _scratch_remount rw
 
 _fsv_scratch_begin_subtest "Enabling verity on file open for writing fails with ETXTBSY"
 echo foo > $fsv_file
 exec 3<> $fsv_file
-_fsv_enable $fsv_file |& _filter_scratch
+_fsv_enable $fsv_file |& filter_output
 exec 3<&-
 verify_data_readable $fsv_file
 
@@ -103,7 +108,7 @@ dd if=/dev/zero of=$fsv_file bs=1 count=0 seek=$((1 << 34)) status=none
 start_time=$(date +%s)
 $FSVERITY_PROG enable $fsv_file &
 sleep 0.5
-_fsv_enable $fsv_file |& _filter_scratch
+_fsv_enable $fsv_file |& filter_output
 kill %1
 wait
 
@@ -112,11 +117,11 @@ _fsv_create_enable_file $fsv_file >> $seqres.full
 echo "* reading"
 $XFS_IO_PROG -r $fsv_file -c ''
 echo "* xfs_io writing, should be O_RDWR"
-$XFS_IO_PROG $fsv_file -c '' |& _filter_scratch
+$XFS_IO_PROG $fsv_file -c '' |& filter_output
 echo "* bash >>, should be O_APPEND"
-bash -c "echo >> $fsv_file" |& _filter_scratch
+bash -c "echo >> $fsv_file" |& filter_output
 echo "* bash >, should be O_WRONLY|O_CREAT|O_TRUNC"
-bash -c "echo > $fsv_file" |& _filter_scratch
+bash -c "echo > $fsv_file" |& filter_output
 
 _fsv_scratch_begin_subtest "verity file can be read"
 _fsv_create_enable_file $fsv_file >> $seqres.full
@@ -160,7 +165,7 @@ _get_filesize $fsv_file
 
 _fsv_scratch_begin_subtest "Trying to measure non-verity file fails with ENODATA"
 echo foo > $fsv_file
-_fsv_measure $fsv_file |& _filter_scratch
+_fsv_measure $fsv_file |& filter_output
 verify_data_readable $fsv_file
 
 # Test files <= 1 block in size.  These are a bit of a special case since there
-- 
2.31.0

Re: [PATCH -v2] common/filter: add _filter_bash()

[Eric Biggers]

On Sat, Dec 18, 2021 at 11:16:38PM -0500, Theodore Ts'o wrote:
> This is needed to account for bash 5.1 adding line number annotation
> when executing a command via the -c option and it fails.  For example,
> "bash -c 'echo foo > /'" will cause bash 5.1 to report:
> 
>      bash: line 1: /: Is a directory
> 
> instead of:
> 
>      bash: /: Is a directory
> 
> Signed-off-by: Theodore Ts'o <tytso@mit.edu>
> ---
>  common/filter     | 11 +++++++++++
>  tests/generic/572 | 33 +++++++++++++++++++--------------
>  2 files changed, 30 insertions(+), 14 deletions(-)

Reviewed-by: Eric Biggers <ebiggers@google.com>

- Eric

Re: [PATCH] common/filter: add _filter_bash()

[Dave Chinner]

On Mon, Aug 30, 2021 at 07:41:56AM -0400, Theodore Ts'o wrote:
> This is needed to account for bash 5.1 adding line number annotation
> when a command like "bash -c /etc/passwd" fails, e.g., with
> 
>      bash: line 1: /etc/passwd: Permission denid
> 
> instead of:
> 
>      bash: /etc/passwd: Permission denid
> 
> Signed-off-by: Theodore Ts'o <tytso@mit.edu>
> ---
>  common/filter     | 11 +++++++++++
>  tests/generic/572 | 33 +++++++++++++++++++--------------
>  2 files changed, 30 insertions(+), 14 deletions(-)
> 
> diff --git a/common/filter b/common/filter
> index 2efbbd99..4b250e8b 100644
> --- a/common/filter
> +++ b/common/filter
> @@ -661,5 +661,16 @@ _filter_quota_report()
>  		s|^(.*?) (\d+) (\d+) (\d+)|$1 @{[$2 * 1024 /'$bsize']} @{[$3 * 1024 /'$bsize']} @{[$4 * 1024 /'$bsize']}|'
>  }
>  
> +#
> +# Bash 5.1+ adds "line 1: " when printing an error running an executable
> +# for example, "bash -c /etc/passwd" will result in the error
> +# "bash: line 1: /etc/passwd: Permission denied" where as earlier
> +# versions of bash will omit the "line 1: " annotation.
> +#
> +_filter_bash()
> +{
> +	sed -e "s/^bash: line 1: /bash: /"
> +}

If this remains, it needs a much more specific name. "filter_bash"
could mean just about anything...

>  # make sure this script returns success
>  /bin/true
> diff --git a/tests/generic/572 b/tests/generic/572
> index f131c7ed..cded9ac6 100755
> --- a/tests/generic/572
> +++ b/tests/generic/572
> @@ -36,6 +36,11 @@ _scratch_mount
>  fsv_orig_file=$SCRATCH_MNT/file
>  fsv_file=$SCRATCH_MNT/file.fsv
>  
> +filter_output()
> +{
> +    _filter_bash | _filter_scratch
> +}

But given that this is only needed by a single test, why create
a generic "_filter_bash" function? Surely this could simply be:

filter_output()
{
    sed -e "s/^bash: line 1: /bash: /" | _filter_scratch
}

Cheers,

Dave.
-- 
Dave Chinner
david@fromorbit.com

[PATCH] common/filter: add _filter_bash()

[Theodore Ts'o]

This is needed to account for bash 5.1 adding line number annotation
when a command like "bash -c /etc/passwd" fails, e.g., with

     bash: line 1: /etc/passwd: Permission denid

instead of:

     bash: /etc/passwd: Permission denid

Signed-off-by: Theodore Ts'o <tytso@mit.edu>
---
 common/filter     | 11 +++++++++++
 tests/generic/572 | 33 +++++++++++++++++++--------------
 2 files changed, 30 insertions(+), 14 deletions(-)

diff --git a/common/filter b/common/filter
index 2efbbd99..4b250e8b 100644
--- a/common/filter
+++ b/common/filter
@@ -661,5 +661,16 @@ _filter_quota_report()
 		s|^(.*?) (\d+) (\d+) (\d+)|$1 @{[$2 * 1024 /'$bsize']} @{[$3 * 1024 /'$bsize']} @{[$4 * 1024 /'$bsize']}|'
 }
 
+#
+# Bash 5.1+ adds "line 1: " when printing an error running an executable
+# for example, "bash -c /etc/passwd" will result in the error
+# "bash: line 1: /etc/passwd: Permission denied" where as earlier
+# versions of bash will omit the "line 1: " annotation.
+#
+_filter_bash()
+{
+	sed -e "s/^bash: line 1: /bash: /"
+}
+
 # make sure this script returns success
 /bin/true
diff --git a/tests/generic/572 b/tests/generic/572
index f131c7ed..cded9ac6 100755
--- a/tests/generic/572
+++ b/tests/generic/572
@@ -36,6 +36,11 @@ _scratch_mount
 fsv_orig_file=$SCRATCH_MNT/file
 fsv_file=$SCRATCH_MNT/file.fsv
 
+filter_output()
+{
+    _filter_bash | _filter_scratch
+}
+
 verify_data_readable()
 {
 	local file=$1
@@ -48,41 +53,41 @@ verify_data_unreadable()
 	local file=$1
 
 	# try both reading just the first data block, and reading until EOF
-	head -c $FSV_BLOCK_SIZE $file 2>&1 >/dev/null | _filter_scratch
-	md5sum $file |& _filter_scratch
+	head -c $FSV_BLOCK_SIZE $file 2>&1 >/dev/null | filter_output
+	md5sum $file |& filter_output
 }
 
 _fsv_scratch_begin_subtest "Enabling verity on file with verity already enabled fails with EEXIST"
 _fsv_create_enable_file $fsv_file
 echo "(trying again)"
-_fsv_enable $fsv_file |& _filter_scratch
+_fsv_enable $fsv_file |& filter_output
 
 _fsv_scratch_begin_subtest "Enabling verity with invalid hash algorithm fails with EINVAL"
-_fsv_create_enable_file $fsv_file --hash-alg=257 |& _filter_scratch
+_fsv_create_enable_file $fsv_file --hash-alg=257 |& filter_output
 verify_data_readable $fsv_file
 
 _fsv_scratch_begin_subtest "Enabling verity with invalid block size fails with EINVAL"
-_fsv_create_enable_file $fsv_file --block-size=1 |& _filter_scratch
+_fsv_create_enable_file $fsv_file --block-size=1 |& filter_output
 verify_data_readable $fsv_file
 
 _fsv_scratch_begin_subtest "Enabling verity on directory fails with EISDIR"
 mkdir $SCRATCH_MNT/dir
-_fsv_enable $SCRATCH_MNT/dir |& _filter_scratch
+_fsv_enable $SCRATCH_MNT/dir |& filter_output
 
 _fsv_scratch_begin_subtest "Enabling verity with too-long salt fails with EMSGSIZE"
-_fsv_create_enable_file $fsv_file --salt=$(perl -e 'print "A" x 1000') |& _filter_scratch
+_fsv_create_enable_file $fsv_file --salt=$(perl -e 'print "A" x 1000') |& filter_output
 verify_data_readable $fsv_file
 
 _fsv_scratch_begin_subtest "Enabling verity on file on read-only filesystem fails with EROFS"
 echo foo > $fsv_file
 _scratch_remount ro
-_fsv_enable $fsv_file |& _filter_scratch
+_fsv_enable $fsv_file |& filter_output
 _scratch_remount rw
 
 _fsv_scratch_begin_subtest "Enabling verity on file open for writing fails with ETXTBSY"
 echo foo > $fsv_file
 exec 3<> $fsv_file
-_fsv_enable $fsv_file |& _filter_scratch
+_fsv_enable $fsv_file |& filter_output
 exec 3<&-
 verify_data_readable $fsv_file
 
@@ -103,7 +108,7 @@ dd if=/dev/zero of=$fsv_file bs=1 count=0 seek=$((1 << 34)) status=none
 start_time=$(date +%s)
 $FSVERITY_PROG enable $fsv_file &
 sleep 0.5
-_fsv_enable $fsv_file |& _filter_scratch
+_fsv_enable $fsv_file |& filter_output
 kill %1
 wait
 
@@ -112,11 +117,11 @@ _fsv_create_enable_file $fsv_file >> $seqres.full
 echo "* reading"
 $XFS_IO_PROG -r $fsv_file -c ''
 echo "* xfs_io writing, should be O_RDWR"
-$XFS_IO_PROG $fsv_file -c '' |& _filter_scratch
+$XFS_IO_PROG $fsv_file -c '' |& filter_output
 echo "* bash >>, should be O_APPEND"
-bash -c "echo >> $fsv_file" |& _filter_scratch
+bash -c "echo >> $fsv_file" |& filter_output
 echo "* bash >, should be O_WRONLY|O_CREAT|O_TRUNC"
-bash -c "echo > $fsv_file" |& _filter_scratch
+bash -c "echo > $fsv_file" |& filter_output
 
 _fsv_scratch_begin_subtest "verity file can be read"
 _fsv_create_enable_file $fsv_file >> $seqres.full
@@ -160,7 +165,7 @@ _get_filesize $fsv_file
 
 _fsv_scratch_begin_subtest "Trying to measure non-verity file fails with ENODATA"
 echo foo > $fsv_file
-_fsv_measure $fsv_file |& _filter_scratch
+_fsv_measure $fsv_file |& filter_output
 verify_data_readable $fsv_file
 
 # Test files <= 1 block in size.  These are a bit of a special case since there
-- 
2.31.0