[PATCH AUTOSEL 4.14 323/371] dmaengine: imx-sdma: fix size check for sdma script_number

Sasha Levin
2020-01-16T17:30:17Z

From: Robin Gong <yibin.gong@nxp.com>

[ Upstream commit bd73dfabdda280fc5f05bdec79b6721b4b2f035f ]

Illegal memory will be touch if SDMA_SCRIPT_ADDRS_ARRAY_SIZE_V3
(41) exceed the size of structure sdma_script_start_addrs(40),
thus cause memory corrupt such as slob block header so that kernel
trap into while() loop forever in slob_free(). Please refer to below
code piece in imx-sdma.c:
for (i = 0; i < sdma->script_number; i++)
if (addr_arr[i] > 0)
saddr_arr[i] = addr_arr[i]; /* memory corrupt here */
That issue was brought by commit a572460be9cf ("dmaengine: imx-sdma: Add
support for version 3 firmware") because SDMA_SCRIPT_ADDRS_ARRAY_SIZE_V3
(38->41 3 scripts added) not align with script number added in
sdma_script_start_addrs(2 scripts).

Fixes: a572460be9cf ("dmaengine: imx-sdma: Add support for version 3 firmware")
Cc: stable@vger.kernel
Link: https://www.spinics.net/lists/arm-kernel/msg754895.html
Signed-off-by: Robin Gong <yibin.gong@nxp.com>
Reported-by: Jurgen Lambrecht <J.Lambrecht@TELEVIC.com>
Link: https://lore.kernel.org/r/1569347584-3478-1-git-send-email-yibin.gong@nxp.com
[vkoul: update the patch title]
Signed-off-by: Vinod Koul <vkoul@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
drivers/dma/imx-sdma.c | 8 ++++++++
include/linux/platform_data/dma-imx-sdma.h | 3 +++
2 files changed, 11 insertions(+)

diff --git a/drivers/dma/imx-sdma.c b/drivers/dma/imx-sdma.c
index 0fc12a8783e3..99f3f22ed647 100644
--- a/drivers/dma/imx-sdma.c
+++ b/drivers/dma/imx-sdma.c
@@ -1441,6 +1441,14 @@ static void sdma_add_scripts(struct sdma_engine *sdma,
if (!sdma->script_number)
sdma->script_number = SDMA_SCRIPT_ADDRS_ARRAY_SIZE_V1;

+ if (sdma->script_number > sizeof(struct sdma_script_start_addrs)
+ / sizeof(s32)) {
+ dev_err(sdma->dev,
+ "SDMA script number %d not match with firmware.\n",
+ sdma->script_number);
+ return;
+ }
+
for (i = 0; i < sdma->script_number; i++)
if (addr_arr[i] > 0)
saddr_arr[i] = addr_arr[i];
diff --git a/include/linux/platform_data/dma-imx-sdma.h b/include/linux/platform_data/dma-imx-sdma.h
index 6eaa53cef0bd..30e676b36b24 100644
--- a/include/linux/platform_data/dma-imx-sdma.h
+++ b/include/linux/platform_data/dma-imx-sdma.h
@@ -51,7 +51,10 @@ struct sdma_script_start_addrs {
/* End of v2 array */
s32 zcanfd_2_mcu_addr;
s32 zqspi_2_mcu_addr;
+ s32 mcu_2_ecspi_addr;
/* End of v3 array */
+ s32 mcu_2_zqspi_addr;
+ /* End of v4 array */
};

/**
--
2.20.1