[PATCH] checkpatch: Allow space leading blank lines in email headers

[PATCH] checkpatch: Allow space leading blank lines in email headers

[Joe Perches]

Allow a leading space and otherwise blank link in the email headers
as it can be a line wrapped Spamassassin multiple line string or any
other valid rfc 2822/5322 email header.

The line with space causes checkpatch to erroniously think that it's
in the content body, as opposed to headers and thus flag a mail header
as an unwrapped long comment line.

Reported-by: Darren Hart (VMware) <dvhart@infradead.org>
Original-patch-by: John 'Warthog9' Hawley (VMware) <warthog9@eaglescrag.net>
Signed-off-by: Joe Perches <joe@perches.com>
---
 scripts/checkpatch.pl | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/scripts/checkpatch.pl b/scripts/checkpatch.pl
index 832e8150dba3..089c974aa3a5 100755
--- a/scripts/checkpatch.pl
+++ b/scripts/checkpatch.pl
@@ -2628,8 +2628,8 @@ sub process {
 # Check if it's the start of a commit log
 # (not a header line and we haven't seen the patch filename)
 		if ($in_header_lines && $realfile =~ /^$/ &&
-		    !($rawline =~ /^\s+\S/ ||
-		      $rawline =~ /^(commit\b|from\b|[\w-]+:).*$/i)) {
+		    !($rawline =~ /^\s+(?:\S|$)/ ||
+		      $rawline =~ /^(?:commit\b|from\b|[\w-]+:)/i)) {
 			$in_header_lines = 0;
 			$in_commit_log = 1;
 			$has_commit_log = 1;
-- 
2.10.0.rc2.1.g053435c

Re: [PATCH] checkpatch: Allow space leading blank lines in email headers

[Darren Hart]

On Wed, Mar 22, 2017 at 10:35:21PM -0700, Joe Perches wrote:
> Allow a leading space and otherwise blank link in the email headers
> as it can be a line wrapped Spamassassin multiple line string or any
> other valid rfc 2822/5322 email header.
> 
> The line with space causes checkpatch to erroniously think that it's
> in the content body, as opposed to headers and thus flag a mail header
> as an unwrapped long comment line.
> 
> Reported-by: Darren Hart (VMware) <dvhart@infradead.org>
> Original-patch-by: John 'Warthog9' Hawley (VMware) <warthog9@eaglescrag.net>
> Signed-off-by: Joe Perches <joe@perches.com>
> ---
>  scripts/checkpatch.pl | 4 ++--
>  1 file changed, 2 insertions(+), 2 deletions(-)
> 
> diff --git a/scripts/checkpatch.pl b/scripts/checkpatch.pl
> index 832e8150dba3..089c974aa3a5 100755
> --- a/scripts/checkpatch.pl
> +++ b/scripts/checkpatch.pl
> @@ -2628,8 +2628,8 @@ sub process {
>  # Check if it's the start of a commit log
>  # (not a header line and we haven't seen the patch filename)
>  		if ($in_header_lines && $realfile =~ /^$/ &&
> -		    !($rawline =~ /^\s+\S/ ||
> -		      $rawline =~ /^(commit\b|from\b|[\w-]+:).*$/i)) {
> +		    !($rawline =~ /^\s+(?:\S|$)/ ||

First, thanks Joe. The above change alone is sufficient to resolve the specific
issue I observed with the long header fields (RFC 5322 2.2.3) used by spam
assassin.

Tested-by: Darren Hart (VMware) <dvhart@infradead.org>

I do have an open question regarding how we're going about testing for the end
of the header lines. Since we're not just testing for an empty line to separate
headers and body, there is clearly more going on here - but I'm not sure what it
is ... so I can't be sure this doesn't have an unintended consequence.

> +		      $rawline =~ /^(?:commit\b|from\b|[\w-]+:)/i)) {

This appears to be an unrelated change, introducing the non-capturing-group
(?:) and dropping the superfluous .*$ postfix. Did I get that right?

-- 
Darren Hart
VMware Open Source Technology Center

Re: [PATCH] checkpatch: Allow space leading blank lines in email headers

[Joe Perches]

On Wed, 2017-03-22 at 23:20 -0700, Darren Hart wrote:
> I do have an open question regarding how we're going about testing for the end
> of the header lines. Since we're not just testing for an empty line to separate
> headers and body, there is clearly more going on here - but I'm not sure what it
> is ... so I can't be sure this doesn't have an unintended consequence.
> 
> > +		      $rawline =~ /^(?:commit\b|from\b|[\w-]+:)/i)) {
> 
> This appears to be an unrelated change, introducing the non-capturing-group
> (?:) and dropping the superfluous .*$ postfix. Did I get that right?

Exactly right.

The capturing of the initial bit of the match and
testing of the rest of the line is simply unnecessary.

I frequently make localized changes like that when I
notice them.  It's not a problem.

cheers, Joe

Re: [PATCH] checkpatch: Allow space leading blank lines in email headers

[Darren Hart]

On Wed, Mar 22, 2017 at 11:28:40PM -0700, Joe Perches wrote:
> On Wed, 2017-03-22 at 23:20 -0700, Darren Hart wrote:
> > I do have an open question regarding how we're going about testing for the end
> > of the header lines. Since we're not just testing for an empty line to separate
> > headers and body, there is clearly more going on here - but I'm not sure what it
> > is ... so I can't be sure this doesn't have an unintended consequence.
> > 
> > > +		      $rawline =~ /^(?:commit\b|from\b|[\w-]+:)/i)) {
> > 
> > This appears to be an unrelated change, introducing the non-capturing-group
> > (?:) and dropping the superfluous .*$ postfix. Did I get that right?
> 
> Exactly right.
> 
> The capturing of the initial bit of the match and
> testing of the rest of the line is simply unnecessary.
> 
> I frequently make localized changes like that when I
> notice them.  It's not a problem.

Thanks Joe. Your call, when I see unrelated changes in patches to me I ask that
they be broken out or at least mentioned in the commit log - which is why I
asked, in case it slipped in unintentionally.

The fix addresses my concern in what appears to be the simplest possible way,
and generally for long header fields, with minimal change.

In addition to my tested-by, feel free to include my review tag:

Reviewed-by: Darren Hart (VMware) <dvhart@vmware.com>

Thanks to both you and John for the time on this.

-- 
Darren Hart
VMware Open Source Technology Center