From mboxrd@z Thu Jan 1 00:00:00 1970 Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.remote-ip=100.103.45.18 ARC-Seal: i=1; d=subspace.kernel.org; s=arc20261015; a=rsa-sha256; cv=none; t=1794063429; b=eXOOB5RwjWjFXIF9tdx8Lo3SShUzo75EiE43X2vvdUiLruSLL2yHq147QUQpkxtquNWe Svn1s58HAFwZdZLJoVgHl+J+dAQU/siENqr5ApNCsqtvEHhE+zzwW7rCrrUikRr/HeU+A befFFXFIj3jkJ6kHJ7dh+BI4FnlhAvkUTusCOzDIt9ha17E9LljZF64Sk5Lscnx3/IX1F IjY3pPnfITUPjFp4NiZcrIaM/L+W9wBCpsmkUOe1Ie8IDPKb3KwJM65Yo/2nHtQy3zl71 qq2jeveH38KdxcsE+dnHuH756evX2ZiUYdhvrHA03JLg3G6OHuiibrg7S6iLXc7bE9A== ARC-Message-Signature: i=1; d=subspace.kernel.org; s=arc20261015; a=rsa-sha256; c=relaxed/relaxed; t=1794063429; h=Received:DKIM-Signature:From:To:Cc:Subject:Date:Message-ID:X-Mailer: In-Reply-To:References:User-Agent:X-stable:X-Patchwork-Hint: MIME-Version:Content-Transfer-Encoding; bh=yisZXRJWN/2WDct4AP5D1gjk5mMP9U6VBJNULWMmBeU=; b=UVl/lqkcThTHNl+yD8pA5JBa6gElpar/6FJjxu/EQhA9xa55jDlWwBVo6mwBYFXMNuES /oRzlOVCCeiWR0gxdprr+gG8ea8lmvYiwHKa1mF9aOhqzlKe0RCRgmGCvLLQVjpI4eVOl 0WOnqrS+BJTG7TRbMMwGTQSTD2hhuBQcpB2rbUJ6R69Jqt6GQ/T/b5Tn9rcqu0wt8hXsl iqdMWzHafuvPbLB13dCotAH3YRqGuxrRPgAZKVSkByMFkZT1UpeeM/6r/SidZHlhtMsDE yOQKjpTc/W+POFVCg9X3bFezQ8LUqvxTRkYVwhfBX5ELjTFmTYRxqpfZSud1nmWf5nQ== ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dkim=pass header.d=linuxfoundation.org header.i=@linuxfoundation.org header.a=rsa-sha256 header.s=korg header.b="A/6CEBrd"; arc=none smtp.remote-ip=100.103.45.18 Received: from smtp.kernel.org (quasi.space.kernel.org [100.103.45.18]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature ECDSA (prime256v1)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 2AE8C6083625; Sat, 7 Nov 2026 14:57:09 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.a=rsa-sha256 header.s=korg header.b=A/6CEBrd Received: by smtp.kernel.org (Postfix) with ESMTPSA id CCFEC1F0089F; Sat, 7 Nov 2026 14:57:08 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linuxfoundation.org; s=korg; t=1794063429; bh=yisZXRJWN/2WDct4AP5D1gjk5mMP9U6VBJNULWMmBeU=; h=From:To:Cc:Subject:Date:In-Reply-To:References; b=A/6CEBrdHK2Q0PNXRK63NxwQDCqLwBUOshXNFJdwzT6Vt4Vq4p53V67xP2kcg+fpD gLbL5icvuUAwlzUUTsN21muL8HZa/7nmXasC0qDRmq2dDRR4cu1fpa1g1Vw8L7Zuha rBQKmoSE53T5ZUkJC2wDeNHijIbBnK0APR/wcYPQ= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, Guanglei Zhu , Weibin Liu , Mark Brown , Sasha Levin Subject: [PATCH 6.18 593/869] spi: bcm-qspi: reject oversized dummy bytes in mspi exec_mem_op Date: Sat, 7 Nov 2026 08:54:35 -0500 Message-ID: <20261107134913.211854101@linuxfoundation.org> X-Mailer: git-send-email 2.56.0 In-Reply-To: <20261107134852.069646174@linuxfoundation.org> References: <20261107134852.069646174@linuxfoundation.org> User-Agent: quilt/0.69 X-stable: review X-Patchwork-Hint: ignore X-Mailing-List: stable@vger.kernel.org List-Id: List-Post: List-Help: List-Subscribe: List-Unsubscribe: List-Owner: Precedence: list MIME-Version: 1.0 Content-Transfer-Encoding: 8bit 6.18-stable review patch. If anyone has any objections, please let me know. ------------------ From: Weibin Liu [ Upstream commit 9e44f0df3fff215d9033089e85980048c3ac132a ] bcm_qspi_mspi_exec_mem_op() builds a local command buffer cmd[6] holding one opcode byte, up to four address bytes and one spare byte, and sets t[0].len = op->addr.nbytes + op->dummy.nbytes + 1. bcm_qspi_exec_mem_op() only validates op->addr.nbytes <= 4 and never bounds op->dummy.nbytes, which spi_mem_check_op() also leaves unrestricted. With addr.nbytes = 4 and dummy.nbytes >= 2 the length becomes 7 or more, so write_to_hw() reads past cmd[] on the kernel stack and pushes the leaked bytes into the hardware TXRAM. Reject operations whose dummy phase does not fit the remaining byte of cmd[] by requiring op->dummy.nbytes <= 1, so such transfers fall back to the generic SPI path instead of overrunning the buffer. Reviewed-by: Guanglei Zhu Fixes: 5f195ee7d830c ("spi: bcm-qspi: Implement the spi_mem interface") Cc: stable@vger.kernel.org # 4.18+ Signed-off-by: Weibin Liu Link: https://patch.msgid.link/20261015-bcm-qspi-dummy-bytes-v1-1-c319da3c2497@xiaopeng.com Signed-off-by: Mark Brown Signed-off-by: Sasha Levin --- drivers/spi/spi-bcm-qspi.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) diff --git a/drivers/spi/spi-bcm-qspi.c b/drivers/spi/spi-bcm-qspi.c index ae5545be0a45c..de333a4a3200d 100644 --- a/drivers/spi/spi-bcm-qspi.c +++ b/drivers/spi/spi-bcm-qspi.c @@ -1197,8 +1197,9 @@ static int bcm_qspi_exec_mem_op(struct spi_mem *mem, u32 addr = 0, len; u_char *buf; + /* cmd[] holds 1 opcode + 4 address + 1 dummy byte at most */ if (!op->data.nbytes || !op->addr.nbytes || op->addr.nbytes > 4 || - op->data.dir != SPI_MEM_DATA_IN) + op->dummy.nbytes > 1 || op->data.dir != SPI_MEM_DATA_IN) return -EOPNOTSUPP; buf = op->data.buf.in; -- 2.53.0