From: Andrew Morton <akpm@linux-foundation.org>
To: akpm@linux-foundation.org, joe@perches.com, linux-mm@kvack.org,
lukas.bulwahn@gmail.com, mm-commits@vger.kernel.org,
mrinalmni@gmail.com, torvalds@linux-foundation.org
Subject: [patch 10/19] checkpatch: fix the usage of capture group ( ... )
Date: Fri, 04 Sep 2020 16:35:52 -0700 [thread overview]
Message-ID: <20200904233552.kLq6B7QPc%akpm@linux-foundation.org> (raw)
In-Reply-To: <20200904163454.4db0e6ce0c4584d2653678a3@linux-foundation.org>
From: Mrinal Pandey <mrinalmni@gmail.com>
Subject: checkpatch: fix the usage of capture group ( ... )
The usage of "capture group (...)" in the immediate condition after `&&`
results in `$1` being uninitialized. This issues a warning "Use of
uninitialized value $1 in regexp compilation at ./scripts/checkpatch.pl
line 2638".
I noticed this bug while running checkpatch on the set of commits from
v5.7 to v5.8-rc1 of the kernel on the commits with a diff content in their
commit message.
This bug was introduced in the script by commit e518e9a59ec3 ("checkpatch:
emit an error when there's a diff in a changelog"). It has been in the
script since then.
The author intended to store the match made by capture group in variable
`$1`. This should have contained the name of the file as `[\w/]+`
matched. However, this couldn't be accomplished due to usage of capture
group and `$1` in the same regular expression.
Fix this by placing the capture group in the condition before `&&`. Thus,
`$1` can be initialized to the text that capture group matches thereby
setting it to the desired and required value.
Link: https://lkml.kernel.org/r/20200714032352.f476hanaj2dlmiot@mrinalpandey
Fixes: e518e9a59ec3 ("checkpatch: emit an error when there's a diff in a changelog")
Signed-off-by: Mrinal Pandey <mrinalmni@gmail.com>
Reviewed-by: Lukas Bulwahn <lukas.bulwahn@gmail.com>
Tested-by: Lukas Bulwahn <lukas.bulwahn@gmail.com>
Cc: Joe Perches <joe@perches.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
---
scripts/checkpatch.pl | 4 ++--
1 file changed, 2 insertions(+), 2 deletions(-)
--- a/scripts/checkpatch.pl~checkpatch-fix-the-usage-of-capture-group
+++ a/scripts/checkpatch.pl
@@ -2639,8 +2639,8 @@ sub process {
# Check if the commit log has what seems like a diff which can confuse patch
if ($in_commit_log && !$commit_log_has_diff &&
- (($line =~ m@^\s+diff\b.*a/[\w/]+@ &&
- $line =~ m@^\s+diff\b.*a/([\w/]+)\s+b/$1\b@) ||
+ (($line =~ m@^\s+diff\b.*a/([\w/]+)@ &&
+ $line =~ m@^\s+diff\b.*a/[\w/]+\s+b/$1\b@) ||
$line =~ m@^\s*(?:\-\-\-\s+a/|\+\+\+\s+b/)@ ||
$line =~ m/^\s*\@\@ \-\d+,\d+ \+\d+,\d+ \@\@/)) {
ERROR("DIFF_IN_COMMIT_MSG",
_
next prev parent reply other threads:[~2020-09-04 23:35 UTC|newest]
Thread overview: 21+ messages / expand[flat|nested] mbox.gz Atom feed top
2020-09-04 23:34 incoming Andrew Morton
2020-09-04 23:35 ` [patch 01/19] memcg: fix use-after-free in uncharge_batch Andrew Morton
2020-09-04 23:35 ` [patch 02/19] mm: memcg: fix memcg reclaim soft lockup Andrew Morton
2020-09-04 23:35 ` [patch 03/19] mm: slub: fix conversion of freelist_corrupted() Andrew Morton
2020-09-04 23:35 ` [patch 04/19] MAINTAINERS: update Cavium/Marvell entries Andrew Morton
2020-09-04 23:35 ` [patch 05/19] MAINTAINERS: add LLVM maintainers Andrew Morton
2020-09-05 17:25 ` Masahiro Yamada
2020-09-04 23:35 ` [patch 06/19] MAINTAINERS: IA64: mark Status as Odd Fixes only Andrew Morton
2020-09-04 23:35 ` [patch 07/19] mm: track page table modifications in __apply_to_page_range() Andrew Morton
2020-09-04 23:35 ` [patch 08/19] ipc: adjust proc_ipc_sem_dointvec definition to match prototype Andrew Morton
2020-09-04 23:35 ` [patch 09/19] fork: adjust sysctl_max_threads " Andrew Morton
2020-09-04 23:35 ` Andrew Morton [this message]
2020-09-04 23:35 ` [patch 11/19] mm: madvise: fix vma user-after-free Andrew Morton
2020-09-04 23:35 ` [patch 12/19] mm/migrate: fixup setting UFFD_WP flag Andrew Morton
2020-09-04 23:36 ` [patch 13/19] mm/rmap: fixup copying of soft dirty and uffd ptes Andrew Morton
2020-09-04 23:36 ` [patch 14/19] mm/migrate: remove unnecessary is_zone_device_page() check Andrew Morton
2020-09-04 23:36 ` [patch 15/19] mm/migrate: preserve soft dirty in remove_migration_pte() Andrew Morton
2020-09-04 23:36 ` [patch 16/19] mm/hugetlb: try preferred node first when alloc gigantic page from cma Andrew Morton
2020-09-04 23:36 ` [patch 17/19] mm/hugetlb: fix a race between hugetlb sysctl handlers Andrew Morton
2020-09-04 23:36 ` [patch 18/19] mm/khugepaged.c: fix khugepaged's request size in collapse_file Andrew Morton
2020-09-04 23:36 ` [patch 19/19] include/linux/log2.h: add missing () around n in roundup_pow_of_two() Andrew Morton
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=20200904233552.kLq6B7QPc%akpm@linux-foundation.org \
--to=akpm@linux-foundation.org \
--cc=joe@perches.com \
--cc=linux-mm@kvack.org \
--cc=lukas.bulwahn@gmail.com \
--cc=mm-commits@vger.kernel.org \
--cc=mrinalmni@gmail.com \
--cc=torvalds@linux-foundation.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).