i2c: xgene-slimpro: Fix out-of-bounds bug in xgene_slimpro_i2c_xfer()

mainline inclusion
from mainline-v6.3-rc4
commit 92fbb6d1
category: bugfix
bugzilla: https://gitee.com/src-openeuler/kernel/issues/I6XHPL
CVE: CVE-2023-2194

--------------------------------

The data->block[0] variable comes from user and is a number between
0-255. Without proper check, the variable may be very large to cause
an out-of-bounds when performing memcpy in slimpro_i2c_blkwr.

Fix this bug by checking the value of writelen.

Fixes: f6505fba ("i2c: add SLIMpro I2C device driver on APM X-Gene platform")
Signed-off-by: NWei Chen <harperchen1110@gmail.com>
Cc: stable@vger.kernel.org
Reviewed-by: NAndi Shyti <andi.shyti@kernel.org>
Signed-off-by: NWolfram Sang <wsa@kernel.org>
Signed-off-by: NYang Jihong <yangjihong1@huawei.com>
Reviewed-by: NXu Kuohai <xukuohai@huawei.com>
Reviewed-by: NWang Weiyang <wangweiyang2@huawei.com>
Signed-off-by: NYongqiang Liu <liuyongqiang13@huawei.com>

drivers/i2c/busses/i2c-xgene-slimpro.c

@@ -321,6 +321,9 @@ static int slimpro_i2c_blkwr(struct slimpro_i2c_dev *ctx, u32 chip,
 	u32 msg[3];
 	int rc;
 
+	if (writelen > I2C_SMBUS_BLOCK_MAX)
+		return -EINVAL;
+
 	memcpy(ctx->dma_buffer, data, writelen);
 	paddr = dma_map_single(ctx->dev, ctx->dma_buffer, writelen,
 			       DMA_TO_DEVICE);