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[71.126.255.178]) by smtp.gmail.com with ESMTPSA id af79cd13be357-945d48316f4sm57268885a.25.2026.11.03.15.59.08 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Tue, 03 Nov 2026 15:59:08 -0800 (PST) Date: Tue, 03 Nov 2026 18:59:07 -0500 Message-ID: X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Post: List-Help: List-Subscribe: List-Unsubscribe: List-Owner: Precedence: list MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit X-Mailer: pstg-pwork:20261103_1853/pstg-lib:20261103_1851/pstg-pwork:20261103_1853 From: Paul Moore To: Babanpreet Singh , Eric Paris Cc: audit@vger.kernel.org, linux-kernel@vger.kernel.org, Babanpreet Singh , syzbot+39b8fea0641107a1ccee@syzkaller.appspotmail.com Subject: Re: [PATCH v2] audit: annotate the lockless read of the audit control lock owner References: <20261008034403.7-1-bbnpreetsingh@gmail.com> In-Reply-To: <20261008034403.7-1-bbnpreetsingh@gmail.com> On Oct 7, 2026 Babanpreet Singh wrote: > > audit_ctl_owner_current() reads the lock owner without taking the lock > and KCSAN complains about it. Only the current task can store itself as > owner, so the check can't give a wrong answer. Mark the accesses with > READ_ONCE() and WRITE_ONCE(). > > Reported-by: syzbot+39b8fea0641107a1ccee@syzkaller.appspotmail.com > Closes: https://syzkaller.appspot.com/bug?extid=39b8fea0641107a1ccee > Assisted-by: Claude:claude-opus-5-5 > Signed-off-by: Babanpreet Singh > Reviewed-by: Bradley Morgan > Tested-by: Bradley Morgan # Power10 > --- > v2: drop the comment in audit_ctl_owner_current(). The KCSAN build of > audit.o disassembles the same as v1. > v1: https://lore.kernel.org/all/20261002011712.7-1-bbnpreetsingh@gmail.com/ > Compile tested only (gcc W=1 and the KCSAN instrumentation diff); I > could not reproduce the race in QEMU. > > kernel/audit.c | 6 +++--- > 1 file changed, 3 insertions(+), 3 deletions(-) Merged into audit/dev, thanks! -- paul-moore.com