From mboxrd@z Thu Jan 1 00:00:00 1970 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 634C814A99; Mon, 23 Oct 2023 11:08:12 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b="ZehO/rgK" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 9982CC433C7; Mon, 23 Oct 2023 11:08:11 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1698059292; bh=xvfO7LxZUzWluuraflXkEgE6nuqlSw9WqGkQrxlBTFg=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=ZehO/rgK980EY7d8QX4kv4iDKZHQUiC/3s78NTon9Fd7xp3ihukQlI9uhTfKfIvc9 wWT8uNq5jHQdLR5r0nXQbZjm7C9AVmIUlmC1+RhJVFKeSqc13XUMWQrZaGj5iKX+cb RMnT4bL/6Ku6T5aPaCY8zJ3wetji8TC2cTiMezzQ= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, Mirko Lindner , Stephen Hemminger , "David S. Miller" , Eric Dumazet , Jakub Kicinski , Paolo Abeni , netdev@vger.kernel.org, kernel test robot , Alexander Lobakin , Kees Cook , "Gustavo A. R. Silva" , Sasha Levin Subject: [PATCH 6.5 129/241] sky2: Make sure there is at least one frag_addr available Date: Mon, 23 Oct 2023 12:55:15 +0200 Message-ID: <20231023104837.012775048@linuxfoundation.org> X-Mailer: git-send-email 2.42.0 In-Reply-To: <20231023104833.832874523@linuxfoundation.org> References: <20231023104833.832874523@linuxfoundation.org> User-Agent: quilt/0.67 X-stable: review X-Patchwork-Hint: ignore Precedence: bulk X-Mailing-List: netdev@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit 6.5-stable review patch. If anyone has any objections, please let me know. ------------------ From: Kees Cook [ Upstream commit 6a70e5cbedaf8ad10528ac9ac114f3ec20f422df ] In the pathological case of building sky2 with 16k PAGE_SIZE, the frag_addr[] array would never be used, so the original code was correct that size should be 0. But the compiler now gets upset with 0 size arrays in places where it hasn't eliminated the code that might access such an array (it can't figure out that in this case an rx skb with fragments would never be created). To keep the compiler happy, make sure there is at least 1 frag_addr in struct rx_ring_info: In file included from include/linux/skbuff.h:28, from include/net/net_namespace.h:43, from include/linux/netdevice.h:38, from drivers/net/ethernet/marvell/sky2.c:18: drivers/net/ethernet/marvell/sky2.c: In function 'sky2_rx_unmap_skb': include/linux/dma-mapping.h:416:36: warning: array subscript i is outside array bounds of 'dma_addr_t[0]' {aka 'long long unsigned int[]'} [-Warray-bounds=] 416 | #define dma_unmap_page(d, a, s, r) dma_unmap_page_attrs(d, a, s, r, 0) | ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ drivers/net/ethernet/marvell/sky2.c:1257:17: note: in expansion of macro 'dma_unmap_page' 1257 | dma_unmap_page(&pdev->dev, re->frag_addr[i], | ^~~~~~~~~~~~~~ In file included from drivers/net/ethernet/marvell/sky2.c:41: drivers/net/ethernet/marvell/sky2.h:2198:25: note: while referencing 'frag_addr' 2198 | dma_addr_t frag_addr[ETH_JUMBO_MTU >> PAGE_SHIFT]; | ^~~~~~~~~ With CONFIG_PAGE_SIZE_16KB=y, PAGE_SHIFT == 14, so: #define ETH_JUMBO_MTU 9000 causes "ETH_JUMBO_MTU >> PAGE_SHIFT" to be 0. Use "?: 1" to solve this build warning. Cc: Mirko Lindner Cc: Stephen Hemminger Cc: "David S. Miller" Cc: Eric Dumazet Cc: Jakub Kicinski Cc: Paolo Abeni Cc: netdev@vger.kernel.org Reported-by: kernel test robot Closes: https://lore.kernel.org/oe-kbuild-all/202309191958.UBw1cjXk-lkp@intel.com/ Reviewed-by: Alexander Lobakin Signed-off-by: Kees Cook Reviewed-by: Gustavo A. R. Silva Signed-off-by: David S. Miller Signed-off-by: Sasha Levin --- drivers/net/ethernet/marvell/sky2.h | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/drivers/net/ethernet/marvell/sky2.h b/drivers/net/ethernet/marvell/sky2.h index ddec1627f1a7b..8d0bacf4e49cc 100644 --- a/drivers/net/ethernet/marvell/sky2.h +++ b/drivers/net/ethernet/marvell/sky2.h @@ -2195,7 +2195,7 @@ struct rx_ring_info { struct sk_buff *skb; dma_addr_t data_addr; DEFINE_DMA_UNMAP_LEN(data_size); - dma_addr_t frag_addr[ETH_JUMBO_MTU >> PAGE_SHIFT]; + dma_addr_t frag_addr[ETH_JUMBO_MTU >> PAGE_SHIFT ?: 1]; }; enum flow_control { -- 2.40.1