[XS] Change in coreboot[main]: soc/mediatek/mt8188/spi: Fix out-of-bound array access for pad_funcs

[Yu-Ping Wu (Code Review)]

Yu-Ping Wu has submitted this change. ( https://review.coreboot.org/c/coreboot/+/84950?usp=email )

Change subject: soc/mediatek/mt8188/spi: Fix out-of-bound array access for pad_funcs
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soc/mediatek/mt8188/spi: Fix out-of-bound array access for pad_funcs

The size of the inner array of the 2-dimensional array pad_funcs should
be 4 instead of SPI_BUS_NUMBER (6). This bug leads to two extra
gpio_set_mode() calls with unexpected GPIOs.

Inspecting spi.o, the data immediately after the .rodata.pad_funcs
section is .rodata.spi_ctrlr_bus_map, with the following data:

00000428  00 00 00 00 00 00 00 00  00 00 00 00 05 00 00 00
 00000438  00 00 00 00 00 00 00 00  ...

This is equivalent to the following calls:

gpio_set_mode(GPIO(GPIO05), 0);
 gpio_set_mode(GPIO(GPIO00), 0);

The second call is already included in the pad_funcs array, so the first
call is the only practical impact of this bug.

Change-Id: I9c44f09b3cdadbbf039b95efca7144f213672092
Signed-off-by: Yu-Ping Wu 
Reviewed-on: https://review.coreboot.org/c/coreboot/+/84950
Tested-by: build bot (Jenkins) 
Reviewed-by: Yidi Lin 
Reviewed-by: Hung-Te Lin 
Reviewed-by: Paul Menzel 
---
M src/soc/mediatek/mt8188/spi.c
1 file changed, 1 insertion(+), 1 deletion(-)

Approvals:
  Paul Menzel: Looks good to me, but someone else must approve
  Hung-Te Lin: Looks good to me, approved
  Yidi Lin: Looks good to me, approved
  build bot (Jenkins): Verified

diff --git a/src/soc/mediatek/mt8188/spi.c b/src/soc/mediatek/mt8188/spi.c
index 994663d..66fbf0f 100644
--- a/src/soc/mediatek/mt8188/spi.c
+++ b/src/soc/mediatek/mt8188/spi.c
@@ -114,7 +114,7 @@

ptr = pad_funcs[bus];

-	for (unsigned int i = 0; i < SPI_BUS_NUMBER; i++)
+	for (unsigned int i = 0; i < ARRAY_SIZE(pad_funcs[0]); i++)
    	gpio_set_mode(ptr[i].gpio, ptr[i].func);
 }