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Wed, 07 Jan 2026 18:15:30 -0800 (PST) From: Qing Wang To: kees@kernel.org Cc: Liam.Howlett@oracle.com, akpm@linux-foundation.org, bsegall@google.com, david@kernel.org, dietmar.eggemann@arm.com, juri.lelli@redhat.com, linux-kernel@vger.kernel.org, linux-mm@kvack.org, lorenzo.stoakes@oracle.com, mgorman@suse.de, mhocko@suse.com, mingo@redhat.com, peterz@infradead.org, rostedt@goodmis.org, rppt@kernel.org, surenb@google.com, syzbot+e0378d4f4fe57aa2bdd0@syzkaller.appspotmail.com, vbabka@suse.cz, vincent.guittot@linaro.org, vschneid@redhat.com, wangqing7171@gmail.com Subject: Re: [PATCH] fork/pid: Fix use-after-free in __task_pid_nr_ns Date: Thu, 8 Jan 2026 10:15:21 +0800 Message-Id: <20260108021521.3838492-1-wangqing7171@gmail.com> X-Mailer: git-send-email 2.34.1 In-Reply-To: <202601071238.F86C2B8@keescook> References: <202601071238.F86C2B8@keescook> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit On Thu, 08 Jan 2026 at 04:39, Kees Cook wrote: > It seems like there is synchronization missing between the task->signal > assignment and its check in task_pid_ptr? Aren't there other ways of > checking if a task is dead? This change doesn't look right to me... > > -Kees Thanks for your reply. Oleg and I discussed this and concluded that this issue no longer exists. Discussion: https://lore.kernel.org/all/aV5zkjzLTwKQOn9D@redhat.com/#R Qing.