[PATCH v2] checkpatch.pl: warn on invalid commit id

[PATCH v2] checkpatch.pl: warn on invalid commit id

[Matteo Croce]

It can happen that a commit message refers to an invalid commit id, because
the referenced hash changed following a rebase, or simply by mistake.
Add a check in checkpatch.pl which checks that an hash referenced by
a Fixes tag, or just cited in the commit message, is a valid commit id.

    $ scripts/checkpatch.pl <<'EOF'
    Subject: [PATCH] test commit

    Sample test commit to test checkpatch.pl
    Commit 1da177e4c3f4 ("Linux-2.6.12-rc2") really exists,
    commit 0bba044c4ce7 ("tree") is valid but not a commit,
    while commit b4cc0b1c0cca ("unknown") is invalid.

    Fixes: f0cacc14cade ("unknown")
    Fixes: 1da177e4c3f4 ("Linux-2.6.12-rc2")
    EOF
    WARNING: Unknown commit id '0bba044c4ce7', maybe rebased or not pulled?
    #8:
    commit 0bba044c4ce7 ("tree") is valid but not a commit,

    WARNING: Unknown commit id 'b4cc0b1c0cca', maybe rebased or not pulled?
    #9:
    while commit b4cc0b1c0cca ("unknown") is invalid.

    WARNING: Unknown commit id 'f0cacc14cade', maybe rebased or not pulled?
    #11:
    Fixes: f0cacc14cade ("unknown")

    total: 0 errors, 3 warnings, 4 lines checked

Signed-off-by: Matteo Croce <mcroce@redhat.com>
---
 scripts/checkpatch.pl | 11 +++++++++++
 1 file changed, 11 insertions(+)

diff --git a/scripts/checkpatch.pl b/scripts/checkpatch.pl
index a6d436809bf5..3b77279df13b 100755
--- a/scripts/checkpatch.pl
+++ b/scripts/checkpatch.pl
@@ -2898,6 +2898,17 @@ sub process {
 			}
 		}
 
+# check for invalid commit id
+		if ($in_commit_log && $line =~ /(^fixes:|\bcommit)\s+([0-9a-f]{6,40})\b/i) {
+			my $id;
+			my $description;
+			($id, $description) = git_commit_info($2, undef, undef);
+			if (!defined($id)) {
+				WARN("UNKNOWN_COMMIT_ID",
+				     "Unknown commit id '$2', maybe rebased or not pulled?\n" . $herecurr);
+			}
+		}
+
 # ignore non-hunk lines and lines being removed
 		next if (!$hunk_line || $line =~ /^-/);
 
-- 
2.21.0

Re: [PATCH v2] checkpatch.pl: warn on invalid commit id

[Joe Perches]

On Thu, 2019-07-11 at 02:16 +0200, Matteo Croce wrote:
> It can happen that a commit message refers to an invalid commit id, because
> the referenced hash changed following a rebase, or simply by mistake.
> Add a check in checkpatch.pl which checks that an hash referenced by
> a Fixes tag, or just cited in the commit message, is a valid commit id.

Thanks Matteo, this seems sensible.

>     $ scripts/checkpatch.pl <<'EOF'
>     Subject: [PATCH] test commit
> 
>     Sample test commit to test checkpatch.pl
>     Commit 1da177e4c3f4 ("Linux-2.6.12-rc2") really exists,
>     commit 0bba044c4ce7 ("tree") is valid but not a commit,
>     while commit b4cc0b1c0cca ("unknown") is invalid.
> 
>     Fixes: f0cacc14cade ("unknown")
>     Fixes: 1da177e4c3f4 ("Linux-2.6.12-rc2")
>     EOF
>     WARNING: Unknown commit id '0bba044c4ce7', maybe rebased or not pulled?
>     #8:
>     commit 0bba044c4ce7 ("tree") is valid but not a commit,
> 
>     WARNING: Unknown commit id 'b4cc0b1c0cca', maybe rebased or not pulled?
>     #9:
>     while commit b4cc0b1c0cca ("unknown") is invalid.
> 
>     WARNING: Unknown commit id 'f0cacc14cade', maybe rebased or not pulled?
>     #11:
>     Fixes: f0cacc14cade ("unknown")
> 
>     total: 0 errors, 3 warnings, 4 lines checked
> 
> Signed-off-by: Matteo Croce <mcroce@redhat.com>
> ---
>  scripts/checkpatch.pl | 11 +++++++++++
>  1 file changed, 11 insertions(+)
> 
> diff --git a/scripts/checkpatch.pl b/scripts/checkpatch.pl
> index a6d436809bf5..3b77279df13b 100755
> --- a/scripts/checkpatch.pl
> +++ b/scripts/checkpatch.pl
> @@ -2898,6 +2898,17 @@ sub process {
>  			}
>  		}
>  
> +# check for invalid commit id
> +		if ($in_commit_log && $line =~ /(^fixes:|\bcommit)\s+([0-9a-f]{6,40})\b/i) {
> +			my $id;
> +			my $description;
> +			($id, $description) = git_commit_info($2, undef, undef);
> +			if (!defined($id)) {
> +				WARN("UNKNOWN_COMMIT_ID",
> +				     "Unknown commit id '$2', maybe rebased or not pulled?\n" . $herecurr);
> +			}
> +		}
> +
>  # ignore non-hunk lines and lines being removed
>  		next if (!$hunk_line || $line =~ /^-/);
>  

Re: [PATCH v2] checkpatch.pl: warn on invalid commit id

[Andrew Morton]

On Thu, 11 Jul 2019 02:16:40 +0200 Matteo Croce <mcroce@redhat.com> wrote:

> It can happen that a commit message refers to an invalid commit id, because
> the referenced hash changed following a rebase, or simply by mistake.
> Add a check in checkpatch.pl which checks that an hash referenced by
> a Fixes tag, or just cited in the commit message, is a valid commit id.
> 
>     $ scripts/checkpatch.pl <<'EOF'
>     Subject: [PATCH] test commit
> 
>     Sample test commit to test checkpatch.pl
>     Commit 1da177e4c3f4 ("Linux-2.6.12-rc2") really exists,
>     commit 0bba044c4ce7 ("tree") is valid but not a commit,
>     while commit b4cc0b1c0cca ("unknown") is invalid.
> 
>     Fixes: f0cacc14cade ("unknown")
>     Fixes: 1da177e4c3f4 ("Linux-2.6.12-rc2")
>     EOF
>     WARNING: Unknown commit id '0bba044c4ce7', maybe rebased or not pulled?
>     #8:
>     commit 0bba044c4ce7 ("tree") is valid but not a commit,
> 
>     WARNING: Unknown commit id 'b4cc0b1c0cca', maybe rebased or not pulled?
>     #9:
>     while commit b4cc0b1c0cca ("unknown") is invalid.
> 
>     WARNING: Unknown commit id 'f0cacc14cade', maybe rebased or not pulled?
>     #11:
>     Fixes: f0cacc14cade ("unknown")
> 
>     total: 0 errors, 3 warnings, 4 lines checked
> 
> ...
>
> --- a/scripts/checkpatch.pl
> +++ b/scripts/checkpatch.pl
> @@ -2898,6 +2898,17 @@ sub process {
>  			}
>  		}
>  
> +# check for invalid commit id
> +		if ($in_commit_log && $line =~ /(^fixes:|\bcommit)\s+([0-9a-f]{6,40})\b/i) {
> +			my $id;
> +			my $description;
> +			($id, $description) = git_commit_info($2, undef, undef);
> +			if (!defined($id)) {
> +				WARN("UNKNOWN_COMMIT_ID",
> +				     "Unknown commit id '$2', maybe rebased or not pulled?\n" . $herecurr);
> +			}
> +		}
> +

What does it do if we're not operating in a git directory? For example,
I work in /usr/src/25 and my git repo is in ../git26.

Also, what happens relatively often is that someone quotes a linux-next
or long-term-stable hash.  If the user has those trees in the git repo,
I assume they won't be informed of the inappropriate hash?

Re: [PATCH v2] checkpatch.pl: warn on invalid commit id

[Matteo Croce]

On Thu, Jul 25, 2019 at 5:07 AM Andrew Morton <akpm@linux-foundation.org> wrote:
> What does it do if we're not operating in a git directory? For example,
> I work in /usr/src/25 and my git repo is in ../git26.
>

If .git is not found, the check is disabled

> Also, what happens relatively often is that someone quotes a linux-next
> or long-term-stable hash.  If the user has those trees in the git repo,
> I assume they won't be informed of the inappropriate hash?
>

In this case it won't warn, but this should not be a problem, as the
hash doesn't change following a merge.
The problem is just if the other tree gets rebased, or if the other
tree gets never merged, e.g. stable/linux-*

Cheers,


--
Matteo Croce
per aspera ad upstream

Re: [PATCH v2] checkpatch.pl: warn on invalid commit id

[Andrew Morton]

On Thu, 25 Jul 2019 11:26:04 +0200 Matteo Croce <mcroce@redhat.com> wrote:

> On Thu, Jul 25, 2019 at 5:07 AM Andrew Morton <akpm@linux-foundation.org> wrote:
> > What does it do if we're not operating in a git directory? For example,
> > I work in /usr/src/25 and my git repo is in ../git26.
> >
> 
> If .git is not found, the check is disabled

We could permit user to set an environment variable to tell checkpatch
where the kernel git tree resides.

> > Also, what happens relatively often is that someone quotes a linux-next
> > or long-term-stable hash.  If the user has those trees in the git repo,
> > I assume they won't be informed of the inappropriate hash?
> >
> 
> In this case it won't warn, but this should not be a problem, as the
> hash doesn't change following a merge.
> The problem is just if the other tree gets rebased, or if the other
> tree gets never merged, e.g. stable/linux-*

linux-next patches get rebased quite often.  I guess this is acceptable
- failing to warn about an error is better than warning about
not-an-error.

Re: [PATCH v2] checkpatch.pl: warn on invalid commit id

[Matteo Croce]

On July 26, 2019 2:22:05 AM GMT+02:00, Andrew Morton <akpm@linux-foundation.org> wrote:
> On Thu, 25 Jul 2019 11:26:04 +0200 Matteo Croce <mcroce@redhat.com>
> wrote:
> 
> > On Thu, Jul 25, 2019 at 5:07 AM Andrew Morton
> <akpm@linux-foundation.org> wrote:
> > > What does it do if we're not operating in a git directory? For
> example,
> > > I work in /usr/src/25 and my git repo is in ../git26.
> > >
> > 
> > If .git is not found, the check is disabled
> 
> We could permit user to set an environment variable to tell checkpatch
> where the kernel git tree resides.
> 

Maybe GIT_DIR already does it.

> > > Also, what happens relatively often is that someone quotes a
> linux-next
> > > or long-term-stable hash.  If the user has those trees in the git
> repo,
> > > I assume they won't be informed of the inappropriate hash?
> > >
> > 
> > In this case it won't warn, but this should not be a problem, as the
> > hash doesn't change following a merge.
> > The problem is just if the other tree gets rebased, or if the other
> > tree gets never merged, e.g. stable/linux-*
> 
> linux-next patches get rebased quite often.

I see :)

-- 
Matteo Croce
per aspera ad upstream

Re: [PATCH v2] checkpatch.pl: warn on invalid commit id

[Andrew Morton]

On Fri, 26 Jul 2019 03:17:32 +0200 Matteo Croce <mcroce@redhat.com> wrote:

> > > If .git is not found, the check is disabled
> > 
> > We could permit user to set an environment variable to tell checkpatch
> > where the kernel git tree resides.
> > 
> 
> Maybe GIT_DIR already does it.

Yes, that works.  GIT_DIR=<wherever>/.git