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Fri, 19 Apr 2024 09:33:53 -0700 (PDT) Received: from kernelexploit-virtual-machine.localdomain ([121.185.186.233]) by smtp.gmail.com with ESMTPSA id h5-20020a056a00000500b006ed4aa9d5c0sm3419410pfk.188.2024.04.19.09.33.52 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Fri, 19 Apr 2024 09:33:53 -0700 (PDT) From: Jeongjun Park To: syzbot+d4c06e848a1c1f9f726f@syzkaller.appspotmail.com Cc: linux-kernel@vger.kernel.org, syzkaller-bugs@googlegroups.com Subject: Re: [syzbot] possible deadlock in input_event (2) Date: Sat, 20 Apr 2024 01:33:49 +0900 Message-Id: <20240419163349.20540-1-aha310510@gmail.com> X-Mailer: git-send-email 2.34.1 In-Reply-To: <0000000000006d6f4105d2fe05ed@google.com> References: <0000000000006d6f4105d2fe05ed@google.com> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit please test deadlock in input_event #syz test git://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git master --- fs/fcntl.c | 6 +++--- 1 file changed, 3 insertions(+), 3 deletions(-) diff --git a/fs/fcntl.c b/fs/fcntl.c index 54cc85d3338e..30f4d75fdb03 100644 --- a/fs/fcntl.c +++ b/fs/fcntl.c @@ -829,7 +829,7 @@ int send_sigurg(struct fown_struct *fown) struct task_struct *p; enum pid_type type; struct pid *pid; - unsigned long flags; + unsigned long flags, read_flags; int ret = 0; read_lock_irqsave(&fown->lock, flags); @@ -848,11 +848,11 @@ int send_sigurg(struct fown_struct *fown) send_sigurg_to_task(p, fown, type); rcu_read_unlock(); } else { - read_lock(&tasklist_lock); + read_lock_irqsave(&tasklist_lock, read_flags); do_each_pid_task(pid, type, p) { send_sigurg_to_task(p, fown, type); } while_each_pid_task(pid, type, p); - read_unlock(&tasklist_lock); + read_unlock_irqrestore(&tasklist_lock, read_flags); } out_unlock_fown: read_unlock_irqrestore(&fown->lock, flags); -- 2.34.1