From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from 013.lax.mailroute.net (013.lax.mailroute.net [199.89.1.16]) (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 311B02AD00 for ; Wed, 25 Mar 2026 21:46:11 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=199.89.1.16 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1774475172; cv=none; b=SrXtGXgFsy3TP7n5S3zfq6ed7hn56FjyfkhgyOcGN2ggRycXyAZU/wN7Koq5zxE1O3Lh1YbZStmUSpu6aHcb7uhnbW1S4OE+6OyPDHPRuw4QkT3yw7rXYtqHPa1yvWj+EOLcsJJHfgmJUYr+UY7mr55/4fGLl7J+UDAlrJS8H9g= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1774475172; c=relaxed/simple; bh=lrOib0qKAqlc0X1obI7YSMTajvyYX72CpLJpOrvAbCA=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version:Content-Type; b=du8DyqWPSFsGrn8xvCliex/RSoqHPTk8L/zwDBJekTckrtDIs3AZPUz9AANBEJj/TtIr92OdJALCDbw380iVTu80Cq9lkPfk2b1YUZQME2NDmdpE586ugEueDcdW4IXCQdY9WZO8qrmLcYiiX99AVpGTzf42vMcao+USM6RAefk= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=reject dis=none) header.from=acm.org; spf=pass smtp.mailfrom=acm.org; dkim=pass (2048-bit key) header.d=acm.org header.i=@acm.org header.b=Hn4SjDgb; arc=none smtp.client-ip=199.89.1.16 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=reject dis=none) header.from=acm.org Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=acm.org Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=acm.org header.i=@acm.org header.b="Hn4SjDgb" Received: from localhost (localhost [127.0.0.1]) by 013.lax.mailroute.net (Postfix) with ESMTP id 4fh0pV6qcNzlgyGr; Wed, 25 Mar 2026 21:46:10 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=acm.org; h= content-transfer-encoding:content-type:content-type:mime-version :references:in-reply-to:x-mailer:message-id:date:date:subject :subject:from:from:received:received; s=mr01; t=1774475165; x= 1777067166; bh=yI8QCvfn9YHC7jW4C3Mpsx117LAxqLX1C8+TDZ3noRY=; b=H n4SjDgbFYkgSSOFaMg0Ad+ffFP+/6iSIef9zvH7oauTbXkrhk4ga0ALHXBsAE15C dS62F6Fv0ZWH788Sxd5xtHRGUDN6SkhKQmZVkYkbucIttXglJ0hcPc1MhZc+Cbzm CcH0F/c995XrUA+1gMVEoKpWxb7mYsCyzFNgEQNdWONrBpXtfFN9kEcH1xrKX7Ah YvTUiiGsmTxfoEII5w/exGoWtFjo7+Npm0iMLDJjp0JwVYweqQ+WbTjK8A3tvFUg LHtUzWFsQVfZXvtbgfANtTT8iiHHZjVSuHlRw1mLW+4m7eh+4tXjGumCw+0CDRtB aLKon3LocJX9ZPalYFT9Q== X-Virus-Scanned: by MailRoute Received: from 013.lax.mailroute.net ([127.0.0.1]) by localhost (013.lax [127.0.0.1]) (mroute_mailscanner, port 10029) with LMTP id D-BmkEGv-Uzq; Wed, 25 Mar 2026 21:46:05 +0000 (UTC) Received: from bvanassche.mtv.corp.google.com (unknown [104.135.180.219]) (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) (Authenticated sender: bvanassche@acm.org) by 013.lax.mailroute.net (Postfix) with ESMTPSA id 4fh0pM0MhMzlgyGh; Wed, 25 Mar 2026 21:46:02 +0000 (UTC) From: Bart Van Assche To: Jens Axboe Cc: linux-block@vger.kernel.org, Christoph Hellwig , Damien Le Moal , Tejun Heo , Bart Van Assche , =?UTF-8?q?Christoph=20B=C3=B6hmwalder?= , Andreas Gruenbacher , Philipp Reisner , Lars Ellenberg , Nathan Chancellor Subject: [PATCH v2 15/26] drbd: Balance RCU calls in drbd_adm_dump_devices() Date: Wed, 25 Mar 2026 14:44:56 -0700 Message-ID: <20260325214518.2854494-16-bvanassche@acm.org> X-Mailer: git-send-email 2.53.0.1018.g2bb0e51243-goog In-Reply-To: <20260325214518.2854494-1-bvanassche@acm.org> References: <20260325214518.2854494-1-bvanassche@acm.org> Precedence: bulk X-Mailing-List: linux-block@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: quoted-printable Make drbd_adm_dump_devices() call rcu_read_lock() before rcu_read_unlock() is called. This has been detected by the Clang thread-safety analyzer. Tested-by: Christoph B=C3=B6hmwalder Cc: Andreas Gruenbacher Fixes: a55bbd375d18 ("drbd: Backport the "status" command") Signed-off-by: Bart Van Assche --- drivers/block/drbd/drbd_nl.c | 8 ++++++-- 1 file changed, 6 insertions(+), 2 deletions(-) diff --git a/drivers/block/drbd/drbd_nl.c b/drivers/block/drbd/drbd_nl.c index e18fa260a662..1f8ffdf9b24e 100644 --- a/drivers/block/drbd/drbd_nl.c +++ b/drivers/block/drbd/drbd_nl.c @@ -3443,8 +3443,10 @@ int drbd_adm_dump_devices(struct sk_buff *skb, str= uct netlink_callback *cb) if (resource_filter) { retcode =3D ERR_RES_NOT_KNOWN; resource =3D drbd_find_resource(nla_data(resource_filter)); - if (!resource) + if (!resource) { + rcu_read_lock(); goto put_result; + } cb->args[0] =3D (long)resource; } } @@ -3693,8 +3695,10 @@ int drbd_adm_dump_peer_devices(struct sk_buff *skb= , struct netlink_callback *cb) if (resource_filter) { retcode =3D ERR_RES_NOT_KNOWN; resource =3D drbd_find_resource(nla_data(resource_filter)); - if (!resource) + if (!resource) { + rcu_read_lock(); goto put_result; + } } cb->args[0] =3D (long)resource; }