From patchwork Sun Sep 29 14:42:30 2024 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Oleg Nesterov X-Patchwork-Id: 13815136 Received: from us-smtp-delivery-124.mimecast.com (us-smtp-delivery-124.mimecast.com [170.10.133.124]) (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 A462717ADF8 for ; Sun, 29 Sep 2024 14:42:51 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=170.10.133.124 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1727620973; cv=none; b=HGHC8yTSTuDWAnGPcmt9OQussKmqS19EU1hKkH8kGEefRmauS5X5Qk0oSm6ttgq/WXhq13WnnQO2brq3yEykjuAHrioKLwm8SSq/IIyfmxxORppGQ3K42/V57I3t0vSZ68s528ZuhAd2knYvxxmlUjZ3ouNc1tochMmfIYoFPag= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1727620973; c=relaxed/simple; bh=6WTZso5WGhvtb2/OxjllcDfJ4f6hMAM6NKTHQqMFnIQ=; h=Date:From:To:Cc:Subject:Message-ID:MIME-Version:Content-Type: Content-Disposition:In-Reply-To; b=Ky97EZV5PMWtiyJjczjJmRBpZWTBjfvyQ1y1q6t+H8QoGvNpelwss41adq+mHIR4l/5VE8cEWz8vHDmb7hyOs7o9RHX26Rts9A6GkKz+Slqr8HAcPusz6YH9I3FYqae73XC3New2exo+xUqeAAVbWxy8+/JIDEsotlt2Wbp5VfI= 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=IH8kdwcO; arc=none smtp.client-ip=170.10.133.124 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="IH8kdwcO" DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1727620970; 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; bh=UjMkCez+I6XaIxZPG+o4NZ0Bsl2LfAkraC0d9Mrst+o=; b=IH8kdwcOpkZWw84ebQ19dbXehgBPuh/BUGMgFSC2Ijuj+eZIy877bMg+Cr6QEuhj8OulWh VM0fvV7v+oePjXsqzhpgRi2hVukSIqZbQXK29dt7xk+KjHdKU+gJ0amWsfiuzsp3ECbGWC Scm1qHzw4m1+HDCskVikMPKyfzSvdAo= Received: from mx-prod-mc-03.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-158-doMx__8qNg-wZ2uUUCItBQ-1; Sun, 29 Sep 2024 10:42:48 -0400 X-MC-Unique: doMx__8qNg-wZ2uUUCItBQ-1 Received: from mx-prod-int-04.mail-002.prod.us-west-2.aws.redhat.com (unknown [10.30.177.40]) (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-03.mail-002.prod.us-west-2.aws.redhat.com (Postfix) with ESMTPS id 82CE018E6A6C; Sun, 29 Sep 2024 14:42:47 +0000 (UTC) Received: from dhcp-27-174.brq.redhat.com (unknown [10.45.224.44]) by mx-prod-int-04.mail-002.prod.us-west-2.aws.redhat.com (Postfix) with SMTP id B8DC01944B22; Sun, 29 Sep 2024 14:42:44 +0000 (UTC) Received: by dhcp-27-174.brq.redhat.com (nbSMTP-1.00) for uid 1000 oleg@redhat.com; Sun, 29 Sep 2024 16:42:34 +0200 (CEST) Date: Sun, 29 Sep 2024 16:42:30 +0200 From: Oleg Nesterov To: Andrii Nakryiko , Jiri Olsa , Masami Hiramatsu , Peter Zijlstra Cc: Liao Chang , linux-kernel@vger.kernel.org, linux-trace-kernel@vger.kernel.org Subject: [PATCH 1/7] uprobes: don't abuse get_utask() in pre_ssout() and prepare_uretprobe() Message-ID: <20240929144230.GA9468@redhat.com> Precedence: bulk X-Mailing-List: linux-trace-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Disposition: inline In-Reply-To: <20240929144201.GA9429@redhat.com> User-Agent: Mutt/1.5.24 (2015-08-30) X-Scanned-By: MIMEDefang 3.0 on 10.30.177.40 handle_swbp() calls get_utask() before prepare_uretprobe() or pre_ssout() can be called, they can simply use current->utask which can't be NULL. Signed-off-by: Oleg Nesterov --- kernel/events/uprobes.c | 14 +++----------- 1 file changed, 3 insertions(+), 11 deletions(-) diff --git a/kernel/events/uprobes.c b/kernel/events/uprobes.c index 4b52cb2ae6d6..2a9cdd5c82d7 100644 --- a/kernel/events/uprobes.c +++ b/kernel/events/uprobes.c @@ -1908,18 +1908,14 @@ static void cleanup_return_instances(struct uprobe_task *utask, bool chained, static void prepare_uretprobe(struct uprobe *uprobe, struct pt_regs *regs) { - struct return_instance *ri; - struct uprobe_task *utask; + struct uprobe_task *utask = current->utask; unsigned long orig_ret_vaddr, trampoline_vaddr; + struct return_instance *ri; bool chained; if (!get_xol_area()) return; - utask = get_utask(); - if (!utask) - return; - if (utask->depth >= MAX_URETPROBE_DEPTH) { printk_ratelimited(KERN_INFO "uprobe: omit uretprobe due to" " nestedness limit pid/tgid=%d/%d\n", @@ -1980,14 +1976,10 @@ static void prepare_uretprobe(struct uprobe *uprobe, struct pt_regs *regs) static int pre_ssout(struct uprobe *uprobe, struct pt_regs *regs, unsigned long bp_vaddr) { - struct uprobe_task *utask; + struct uprobe_task *utask = current->utask; unsigned long xol_vaddr; int err; - utask = get_utask(); - if (!utask) - return -ENOMEM; - if (!try_get_uprobe(uprobe)) return -EINVAL;