From nobody Tue Oct 7 13:08:05 2025 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (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 CFAB12E610F; Wed, 9 Jul 2025 14:59:13 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1752073153; cv=none; b=gG9TIm/IcDcHv166j2ungoT878u7MCVGeBWoN9PWOm3eGzmX+rX/cvhysOp1GtsP2k1Y2oBo5TyScSooTp1qa2DSwCpFvP2Vvyw3vNLwLnAyaIMRYGlAPlh+Xfzz1o3wM7EmhXOfPlECgwu6UFAIq8vtmP1qX+xPGSoYe5dK9fk= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1752073153; c=relaxed/simple; bh=1CeZul5hY2ntHtGKA2dLPFSaFc71yvfAyz7ig1jnzU4=; h=From:To:Cc:Subject:Date:Message-Id:MIME-Version; b=l98Y/xkNmA5w46rOuN+8p+HtvHFIRxMJ2QNvAuD7DXxz+WpVMBYi8zMHpn7pfOijO/P3SLIjgOwSc9DhhR1gxnp2eVl+l1vZd7crLnNaGDTLyw1Y0zHk5P6TaeIuqKYTRoBAty6BBgbGrwc23AxKkETY33qglWE98fzkzjIgyu4= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=mM5Kv/pE; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="mM5Kv/pE" Received: by smtp.kernel.org (Postfix) with ESMTPSA id B6A8EC4CEEF; Wed, 9 Jul 2025 14:59:10 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1752073153; bh=1CeZul5hY2ntHtGKA2dLPFSaFc71yvfAyz7ig1jnzU4=; h=From:To:Cc:Subject:Date:From; b=mM5Kv/pE+vbUINtkrIlWm0bImRp4MudOR+/qekSMwYSInWQxQLvAnKPE1IQb3KweJ V1OtlX5BVW+7qr2nRpKAk+bgraaqplJ3qZSl1vSAoEDIq/Cfom/2xkcrhatUk+0AS3 jit5PhCBOjlgu/AB7t8cS3ghBNPyJqGLsO6S+I+d0hZAgCreZahIXTpLaGWuZeSmbA BSrt75TaSi2w+bX2qIL9bL/N6d1tzh2opNLSCLjPIAWe5t3yuOLC5/hF0H4y23bk+h PygM4xNHCLuhdlcAavHtTovOZP+mgqGs/Zuz1mobGu1o/q4yxewHWvnVNpiDvUweV2 XiEvpiz+NBN+A== From: Arnd Bergmann To: Jiri Pirko , "David S. Miller" , Eric Dumazet , Jakub Kicinski , Paolo Abeni , Mark Bloch , Tariq Toukan , Carolina Jubran Cc: Arnd Bergmann , Simon Horman , Cosmin Ratiu , Przemek Kitszel , netdev@vger.kernel.org, linux-kernel@vger.kernel.org Subject: [PATCH] [v2] devlink: move DEVLINK_ATTR_MAX-sized array off stack Date: Wed, 9 Jul 2025 16:59:00 +0200 Message-Id: <20250709145908.259213-1-arnd@kernel.org> X-Mailer: git-send-email 2.39.5 Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: quoted-printable Content-Type: text/plain; charset="utf-8" From: Arnd Bergmann There are many possible devlink attributes, so having an array of them on the stack can cause a warning for excessive stack usage: net/devlink/rate.c: In function 'devlink_nl_rate_tc_bw_parse': net/devlink/rate.c:382:1: error: the frame size of 1648 bytes is larger tha= n 1536 bytes [-Werror=3Dframe-larger-than=3D] Change this to dynamic allocation instead. Fixes: 566e8f108fc7 ("devlink: Extend devlink rate API with traffic classes= bandwidth management") Signed-off-by: Arnd Bergmann --- I see that only two of the many array entries are actually used in this function: DEVLINK_ATTR_RATE_TC_INDEX and DEVLINK_ATTR_RATE_TC_BW. If there is an interface to extract just a single entry, using that would be a little easier than the kcalloc(). v2: use __free() helper to simplify cleanup --- net/devlink/rate.c | 6 +++++- 1 file changed, 5 insertions(+), 1 deletion(-) diff --git a/net/devlink/rate.c b/net/devlink/rate.c index d39300a9b3d4..3c4689c6cefb 100644 --- a/net/devlink/rate.c +++ b/net/devlink/rate.c @@ -346,10 +346,14 @@ static int devlink_nl_rate_tc_bw_parse(struct nlattr = *parent_nest, u32 *tc_bw, unsigned long *bitmap, struct netlink_ext_ack *extack) { - struct nlattr *tb[DEVLINK_ATTR_MAX + 1]; + struct nlattr **tb __free(kfree) =3D NULL; u8 tc_index; int err; =20 + tb =3D kcalloc(DEVLINK_ATTR_MAX + 1, sizeof(struct nlattr *), GFP_KERNEL); + if (!tb) + return -ENOMEM; + err =3D nla_parse_nested(tb, DEVLINK_ATTR_MAX, parent_nest, devlink_dl_rate_tc_bws_nl_policy, extack); if (err) --=20 2.39.5