From mboxrd@z Thu Jan 1 00:00:00 1970 Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.remote-ip=100.103.45.18 ARC-Seal: i=1; d=subspace.kernel.org; s=arc20261015; a=rsa-sha256; cv=none; t=1794060552; b=mvY/2ARkJERn0/iXTl+jcZDKGfys9fADZJKtY4RN1CgNafeHV98a0825K4sMBsj7C9ku a6XoJkDisHykBsCGpxvMOH52DgS6LcQX2YKboRnYsNd0NY6+RxktrbB0PTG5R2Ns6FM80 2RwOx8IMZP3U4lBQM6fAUuhliaOB7KRB0ntHjn3RT0XF4xZT/iRL4sA6J2iSLAG29yXM+ 88X6OeI0CHNua684/uwPCt4GvXKR1KdH7ychC4Hy5Cvy2KF7DptH2vINq08Wn5vwgL8nt HOO1Wb2VfLUjspB3LGv2qLTMd93mU7Ao4LxIhKyeYtpGIUa6hiJtWoJU2qDf3NM400w== ARC-Message-Signature: i=1; d=subspace.kernel.org; s=arc20261015; a=rsa-sha256; c=relaxed/relaxed; t=1794060552; h=Received:DKIM-Signature:From:To:Cc:Subject:Date:Message-ID:X-Mailer: In-Reply-To:References:User-Agent:X-stable:X-Patchwork-Hint: MIME-Version:Content-Transfer-Encoding; bh=ZrD0I1ZTcNPzgNw8TmZAAzQtrYX/tTcoUUW+5LAgaWQ=; b=MFr3pBqycwV7XC6X09KFmypVEV4n3PCNAbjQ5nPvKPT7J/vujSoy/NHndKzxGAZJPld4 EnoEENuqx6aa4IYiIaqUUKnRaKcd00RKq508o5QijYj7Yz1W7I8I4Qr0pUz4lsvEIta5J d0ELy/yNd++ik+8l2E4WLdtgwN0PIB4wFVhD+V5PQ/D7F21YISKTAJON3laCIMyusmseC hQYb9hTZypNecYjkWEby2PAxhcNYwbIqESPvjwjMq5gCAz29xDKPFojVtpZqke+J07pX/ o5K/ds/qAW5WbU6QTmUoMgF7LEY8dryiGWsGFZLTUazszqKXBJ/DhUu8OnXxBbqUMng== ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dkim=pass header.d=linuxfoundation.org header.i=@linuxfoundation.org header.a=rsa-sha256 header.s=korg header.b=03ok7PCn; arc=none smtp.remote-ip=100.103.45.18 Received: from smtp.kernel.org (quasi.space.kernel.org [100.103.45.18]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature ECDSA (prime256v1)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 80875606A326; Sat, 7 Nov 2026 14:09:12 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.a=rsa-sha256 header.s=korg header.b=03ok7PCn Received: by smtp.kernel.org (Postfix) with ESMTPSA id DA8601F0089F; Sat, 7 Nov 2026 14:09:11 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linuxfoundation.org; s=korg; t=1794060552; bh=ZrD0I1ZTcNPzgNw8TmZAAzQtrYX/tTcoUUW+5LAgaWQ=; h=From:To:Cc:Subject:Date:In-Reply-To:References; b=03ok7PCnOgyulNx3T8pblqaDGYbfhCVakblyLDBP9p511QaQQL5mvoiztdv+F+LHj CKc2k20WofBTSE0oMAoMw7/a9kYb4kGjaGejRlcHi50KeRmDcthwvO3nrRGjVZryR7 39/ZtM20z9lk29Zss46l8HK9q01ZOmncXFblz1cs= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, Oleg Nesterov , "Christian Brauner (Amutable)" , Sasha Levin Subject: [PATCH 6.12 0018/1536] fork: move the coredump and exec checks into create_io_thread() Date: Sat, 7 Nov 2026 08:33:54 -0500 Message-ID: <20261107134958.192470907@linuxfoundation.org> X-Mailer: git-send-email 2.56.0 In-Reply-To: <20261107134957.653319350@linuxfoundation.org> References: <20261107134957.653319350@linuxfoundation.org> User-Agent: quilt/0.69 X-stable: review X-Patchwork-Hint: ignore X-Mailing-List: stable@vger.kernel.org List-Id: List-Post: List-Help: List-Subscribe: List-Unsubscribe: List-Owner: Precedence: list MIME-Version: 1.0 Content-Transfer-Encoding: 8bit 6.12-stable review patch. If anyone has any objections, please let me know. ------------------ From: Christian Brauner [ Upstream commit e760200370e4de054b6b5f568a7faa911e2956bb ] Only a PF_USER_WORKER thread returns from get_signal() after a fatal signal and can go on to create a thread. get_signal() sets PF_SIGNALED before it dumps core and before it lets a PF_USER_WORKER thread return. That flags sticks. The exec'ing thread itself is never signaled. But it doesn't need the check anyway as we moved cancellation of io_uring requests before de_thread(). create_io_thread() is the only way a signaled thread creates another one. vhost_task_create() is reached from ioctls alone. io_should_retry_thread() doesn't retry -EINTR, so io-wq callers give up the same way they did when copy_process() refused. Suggested-by: Oleg Nesterov Link: https://lore.kernel.org/r/aq0VLTyxNatFmLOK@redhat.com Link: https://patch.msgid.link/20260921-work-coredump-fixes-v3-13-8e4adb1619e6@kernel.org Acked-by: Oleg Nesterov Signed-off-by: Christian Brauner (Amutable) Stable-dep-of: 1f978881ce6c ("fork: don't create io threads once PF_POSTCOREDUMP is set") Signed-off-by: Sasha Levin --- kernel/fork.c | 4 ++++ 1 file changed, 4 insertions(+) diff --git a/kernel/fork.c b/kernel/fork.c index f22b79d9954a8..c82956f8fc9d5 100644 --- a/kernel/fork.c +++ b/kernel/fork.c @@ -2774,6 +2774,10 @@ struct task_struct *create_io_thread(int (*fn)(void *), void *arg, int node) .user_worker = 1, }; + /* A creator past its fatal signal gets no thread. */ + if (current->flags & PF_SIGNALED) + return ERR_PTR(-EINTR); + return copy_process(NULL, 0, node, &args); } -- 2.53.0