From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from us-smtp-delivery-124.mimecast.com (us-smtp-delivery-124.mimecast.com [170.10.129.124]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 791A6218585 for ; Thu, 9 Jan 2025 14:25:11 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=170.10.129.124 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1736432713; cv=none; b=MMMeWqBU1A45wjV9sxCg8GZJ6iZI8UnNAvlbYmBtOSJQk17f/+h+2uJB5UUpMg2wl7O2i96w8wpKlK0mVtOKZmdEEGzaT43XTtJgYctbjtLd8nEa2laUq4Dt3zeX85qoEJP6XRLoQLxFJ2iewJV01bGkrxEmci3WqanSO1UWoaM= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1736432713; c=relaxed/simple; bh=toDOfdT/dLLxxneMaOhjxbgIjQyaRYqQq8Kg/40SKto=; h=Date:From:To:Cc:Subject:Message-ID:References:MIME-Version: Content-Type:Content-Disposition:In-Reply-To; b=Df1exo3+OyrTZrR+5a7Im9X7cdQ/nA9lSEzz6EP5a2eqxJhF+0oTn3m/8jdYat87Um/lyMJLYogdTPDauN0uEdRpw/GcHGlc4My6WldCnn4jvBdwrO/FjMs6flU2SaPPXfvqT1WA8XWTJbcfBtisMZj1+0Fq3C+4YthxpUIe51Q= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=redhat.com; spf=pass smtp.mailfrom=redhat.com; dkim=pass (1024-bit key) header.d=redhat.com header.i=@redhat.com header.b=GA+HHG1e; arc=none smtp.client-ip=170.10.129.124 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=redhat.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=redhat.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=redhat.com header.i=@redhat.com header.b="GA+HHG1e" DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1736432710; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version:content-type:content-type: in-reply-to:in-reply-to:references:references; bh=6TQ+MRlGX4zoVa4E9hEX0jIlbvnXvUvfeYr2R+u5ruo=; b=GA+HHG1eF964nkbEmGTbYRgEZEAyIhmpGG6owl4SMzA5olHxLsas+Bp0q2txZP9FUrXPF8 DqGTrX54mpWJJueRykFew/EBdYq0i0z+W4CDQQNGWPfremz8QQWvLDDrpAyS0dke3oD9JM OnYdIgCMy7a1D8+xQ8P1D9gE1BfmCDo= Received: from mx-prod-mc-01.mail-002.prod.us-west-2.aws.redhat.com (ec2-54-186-198-63.us-west-2.compute.amazonaws.com [54.186.198.63]) by relay.mimecast.com with ESMTP with STARTTLS (version=TLSv1.3, cipher=TLS_AES_256_GCM_SHA384) id us-mta-631-_xap2Xl0OAKARNgrQ8yOhg-1; Thu, 09 Jan 2025 09:25:07 -0500 X-MC-Unique: _xap2Xl0OAKARNgrQ8yOhg-1 X-Mimecast-MFC-AGG-ID: _xap2Xl0OAKARNgrQ8yOhg Received: from mx-prod-int-02.mail-002.prod.us-west-2.aws.redhat.com (mx-prod-int-02.mail-002.prod.us-west-2.aws.redhat.com [10.30.177.15]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (2048 bits) server-digest SHA256) (No client certificate requested) by mx-prod-mc-01.mail-002.prod.us-west-2.aws.redhat.com (Postfix) with ESMTPS id 483C619560B8; Thu, 9 Jan 2025 14:25:05 +0000 (UTC) Received: from dhcp-27-174.brq.redhat.com (unknown [10.45.225.245]) by mx-prod-int-02.mail-002.prod.us-west-2.aws.redhat.com (Postfix) with SMTP id 44721195E3D9; Thu, 9 Jan 2025 14:25:00 +0000 (UTC) Received: by dhcp-27-174.brq.redhat.com (nbSMTP-1.00) for uid 1000 oleg@redhat.com; Thu, 9 Jan 2025 15:24:40 +0100 (CET) Date: Thu, 9 Jan 2025 15:24:35 +0100 From: Oleg Nesterov To: Jiri Olsa Cc: Peter Zijlstra , Andrii Nakryiko , Masami Hiramatsu , Daniel Borkmann , Max Makarov , bpf@vger.kernel.org, Steven Rostedt , linux-kernel@vger.kernel.org, linux-trace-kernel@vger.kernel.org Subject: Re: [PATCH] uprobes: Fix race in uprobe_free_utask Message-ID: <20250109142434.GD26424@redhat.com> References: <20250109141440.2692173-1-jolsa@kernel.org> Precedence: bulk X-Mailing-List: linux-trace-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20250109141440.2692173-1-jolsa@kernel.org> User-Agent: Mutt/1.5.24 (2015-08-30) X-Scanned-By: MIMEDefang 3.0 on 10.30.177.15 On 01/09, Jiri Olsa wrote: > > --- a/kernel/events/uprobes.c > +++ b/kernel/events/uprobes.c > @@ -1915,6 +1915,7 @@ void uprobe_free_utask(struct task_struct *t) > if (!utask) > return; > > + t->utask = NULL; > WARN_ON_ONCE(utask->active_uprobe || utask->xol_vaddr); > > timer_delete_sync(&utask->ri_timer); > @@ -1924,7 +1925,6 @@ void uprobe_free_utask(struct task_struct *t) > ri = free_ret_instance(ri, true /* cleanup_hprobe */); > > kfree(utask); > - t->utask = NULL; Acked-by: Oleg Nesterov