From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp10.goneo.de (smtp10.goneo.de [85.220.189.106]) (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 65F213890F8; Tue, 2 Jun 2026 16:54:43 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=85.220.189.106 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1780419286; cv=none; b=WgvryUyioUvyCqQGJEIQPNcr/qjs6Ncmty+jJy0DjiTm0dpNMiOvrcLtt2jdDgyrELIBmmA/iY0rAaQkFJm+JjHRMCY5YqU6t6yHaX3WjKF1sz3nrEJk78T8mFn74IMEWG8P+KmVn9V4XzD4Szk8KjVoKuX5ytvU6sc4VLTVNYI= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1780419286; c=relaxed/simple; bh=2no5ts4uR+BRFpbAeaMDuXoBtDm87qzy992Y6dadpc8=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=LSZRgt8pJju+f1VjbLDgsqvkFDGBpB/dg6k/gFfkTsOHExlVMB8NynIUYQSms0smkZCTygD57wsFqRn9qJ3kcy6yxTXbo3sB/0kXYd3+HYbWcwFsVlSjw/Qa5GAsy/p27i/muv6AIlEmc9cr/KKwBDfKsr6cbgknGZmM4u+QO1s= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=none (p=none dis=none) header.from=tk154.de; spf=pass smtp.mailfrom=tk154.de; dkim=pass (2048-bit key) header.d=tk154.de header.i=@tk154.de header.b=j3gCUzoG; arc=none smtp.client-ip=85.220.189.106 Authentication-Results: smtp.subspace.kernel.org; dmarc=none (p=none dis=none) header.from=tk154.de Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=tk154.de Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=tk154.de header.i=@tk154.de header.b="j3gCUzoG" Received: from hub2.goneo.de (hub2.goneo.de [IPv6:2001:1640:5::8:53]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange x25519) (No client certificate requested) by smtp10.goneo.de (Postfix) with ESMTPS id 047A92408DF; Tue, 02 Jun 2026 18:47:11 +0200 (CEST) Received: from hub2.goneo.de (localhost [127.0.0.1]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (4096 bits)) (No client certificate requested) by hub2.goneo.de (Postfix) with ESMTPS id 62576240025; Tue, 2 Jun 2026 18:47:09 +0200 (CEST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=tk154.de; s=DKIM001; t=1780418829; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=C1Ioe8uKiJIxbIqpXcCQ8i5GRjn3ORGyOB/YwWZ/fog=; b=j3gCUzoGqvhDYCXPRFFh4+7S9r5KWF/6PfO8sE8mJEjJDgsmScdh8lAVTYF2mlAdSpzWQh XDSrf6Jp8fYN6ptm4iVVfrNbg0mIB5qX8UOaQ6cClT5HUaB+NBhPyJxUwAHF9UsKe48R/K MMP9YYzex7PgJIgGKgVJ32ie7P6yWLdGzucBnKhNOWjA3tUtQnVbcxjIZhUcstLPJjnVAs QCLqB7HdH8p39Ul5xWC3ZbjIrtWVJQrK/3KCnMYH4a8qkjEPRdi+uPokPenekg/6r7cnXa 86+SxiNxvk/8/G51xCkaHUyenpKkzZBarSmScufdyaCnZ0L4H13S3vnQyZBJ8w== Received: from Til-Notebook.meshlab (unknown [195.37.88.189]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (4096 bits) server-digest SHA256) (No client certificate requested) by hub2.goneo.de (Postfix) with ESMTPSA id 1707F240027; Tue, 2 Jun 2026 18:47:07 +0200 (CEST) From: Til Kaiser To: Marcin Wojtas , Russell King Cc: Andrew Lunn , "David S . Miller" , Eric Dumazet , Jakub Kicinski , Paolo Abeni , Alexei Starovoitov , Daniel Borkmann , Jesper Dangaard Brouer , John Fastabend , Stanislav Fomichev , Matteo Croce , Sven Auhagen , Lorenzo Bianconi , netdev@vger.kernel.org, bpf@vger.kernel.org, linux-kernel@vger.kernel.org, Til Kaiser Subject: [PATCH net v2 2/4] net: mvpp2: limit XDP frame size to the RX buffer Date: Tue, 2 Jun 2026 18:46:33 +0200 Message-ID: <20260602164635.62517-3-mail@tk154.de> X-Mailer: git-send-email 2.54.0 In-Reply-To: <20260602164635.62517-1-mail@tk154.de> References: <20260602164635.62517-1-mail@tk154.de> Precedence: bulk X-Mailing-List: netdev@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-Rspamd-UID: 013330 X-Rspamd-UID: 8cc60b mvpp2 has short and long BM pools, and short pool buffers can be smaller than PAGE_SIZE. The XDP path nevertheless initializes every xdp_buff with PAGE_SIZE as frame size. XDP helpers use frame_sz to validate tail growth and to derive the hard end of the data area. Advertising PAGE_SIZE for short buffers can let bpf_xdp_adjust_tail() grow a packet past the real allocation, corrupting memory or later tripping skb tailroom checks. Initialize the XDP buffer with bm_pool->frag_size so XDP tailroom matches the actual buffer backing the packet. Fixes: 07dd0a7aae7f ("mvpp2: add basic XDP support") Signed-off-by: Til Kaiser --- drivers/net/ethernet/marvell/mvpp2/mvpp2_main.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/drivers/net/ethernet/marvell/mvpp2/mvpp2_main.c b/drivers/net/ethernet/marvell/mvpp2/mvpp2_main.c index 92a701f4fe3f..3372ed27cc8d 100644 --- a/drivers/net/ethernet/marvell/mvpp2/mvpp2_main.c +++ b/drivers/net/ethernet/marvell/mvpp2/mvpp2_main.c @@ -3979,7 +3979,7 @@ static int mvpp2_rx(struct mvpp2_port *port, struct napi_struct *napi, else xdp_rxq = &rxq->xdp_rxq_long; - xdp_init_buff(&xdp, PAGE_SIZE, xdp_rxq); + xdp_init_buff(&xdp, bm_pool->frag_size, xdp_rxq); xdp_prepare_buff(&xdp, data, MVPP2_MH_SIZE + MVPP2_SKB_HEADROOM, rx_bytes, true); -- 2.54.0