From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-alma10-1.taild15c8.ts.net [100.103.45.18]) (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 AE85F348C4E; Sat, 30 May 2026 16:25:29 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=100.103.45.18 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1780158331; cv=none; b=I6IOGV98giH2KzN2pknkjSKQIhTUN6E/wUy1kKQnGPy+bleA61rOpDml+SXy98TGRloOsKR9rMihBIC+84EWHTb1Nq5MoNxBlISEL7+L1R+EZK760PaveVcUub+Vt+awpg0SpJqfrti9GPyDGkip7hfviDqE0tGXCorP461CZqQ= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1780158331; c=relaxed/simple; bh=g+77wZFkFPwza8jiyQfgfCaF90SETTuxLSswJoiewF8=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version:Content-Type; b=diLVYWyo2OGOnW2FvZG0WYyhCtNsivEj5wJJjaI9Pr8FesmR2pIro7dj13Iaz0dydeKkmImFlJZ7BHzWX6VTrvyBXeAIPMK2V2aNaot1fX0kzP8d0xKWZJeiJz67zUbR7FnLZ1lrO+wxcBJwYj1Cb0iV0GezdrGD8Y1woGTdPzQ= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b=xmoKoBsh; arc=none smtp.client-ip=100.103.45.18 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b="xmoKoBsh" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 70AB31F00898; Sat, 30 May 2026 16:25:26 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linuxfoundation.org; s=korg; t=1780158329; bh=SkIyCN8RdIhZZrYdJAgo/wxJLvEue1FC7iZ+fmoWWkc=; h=From:To:Cc:Subject:Date:In-Reply-To:References; b=xmoKoBsh//GOMsiIgEAUn6siZ3QG5FOwi4n4ZK4moClvC5+5jkHMDEsub17ZsiD1G 6Ng/dc4/Angykvj8Hez9mt4Nq7xkvq+cYAh4y8Xpuz8NRDpD1J3BkcV8wWkR3VJgvQ DU92EWRj5QNWfg7LXxUKy7v9HvRzU5Mwr/PIzBQc= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, =?UTF-8?q?Bj=C3=B6rn=20T=C3=B6pel?= , Stanislav Fomichev , Maciej Fijalkowski , Jakub Kicinski , Sasha Levin Subject: [PATCH 6.1 041/969] xsk: tighten UMEM headroom validation to account for tailroom and min frame Date: Sat, 30 May 2026 17:52:45 +0200 Message-ID: <20260530160301.552488452@linuxfoundation.org> X-Mailer: git-send-email 2.53.0 In-Reply-To: <20260530160300.485627683@linuxfoundation.org> References: <20260530160300.485627683@linuxfoundation.org> User-Agent: quilt/0.69 X-stable: review X-Patchwork-Hint: ignore Precedence: bulk X-Mailing-List: patches@lists.linux.dev List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit 6.1-stable review patch. If anyone has any objections, please let me know. ------------------ From: Maciej Fijalkowski [ Upstream commit a315e022a72d95ef5f1d4e58e903cb492b0ad931 ] The current headroom validation in xdp_umem_reg() could leave us with insufficient space dedicated to even receive minimum-sized ethernet frame. Furthermore if multi-buffer would come to play then skb_shared_info stored at the end of XSK frame would be corrupted. HW typically works with 128-aligned sizes so let us provide this value as bare minimum. Multi-buffer setting is known later in the configuration process so besides accounting for 128 bytes, let us also take care of tailroom space upfront. Reviewed-by: Björn Töpel Acked-by: Stanislav Fomichev Fixes: 99e3a236dd43 ("xsk: Add missing check on user supplied headroom size") Signed-off-by: Maciej Fijalkowski Link: https://patch.msgid.link/20260402154958.562179-2-maciej.fijalkowski@intel.com Signed-off-by: Jakub Kicinski Signed-off-by: Sasha Levin --- net/xdp/xdp_umem.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) diff --git a/net/xdp/xdp_umem.c b/net/xdp/xdp_umem.c index 02207e852d796..561290f9e68b5 100644 --- a/net/xdp/xdp_umem.c +++ b/net/xdp/xdp_umem.c @@ -196,7 +196,8 @@ static int xdp_umem_reg(struct xdp_umem *umem, struct xdp_umem_reg *mr) if (!unaligned_chunks && chunks_rem) return -EINVAL; - if (headroom >= chunk_size - XDP_PACKET_HEADROOM) + if (headroom > chunk_size - XDP_PACKET_HEADROOM - + SKB_DATA_ALIGN(sizeof(struct skb_shared_info)) - 128) return -EINVAL; umem->size = size; -- 2.53.0