[coreboot-gerrit] Change in ...coreboot[master]: soc/intel/common: Check bios_size and window_size after MIN operation

[Patrick Georgi (Code Review)]

Patrick Georgi has submitted this change and it was merged. ( https://review.coreboot.org/c/coreboot/+/32924 )

Change subject: soc/intel/common: Check bios_size and window_size after MIN operation
......................................................................

soc/intel/common: Check bios_size and window_size after MIN operation

Clang Static Analyzer version 8.0.0 detects that log2_ceil(bios_size)
and log2_ceil(window_size) are garbage or undefined if the value of
bios_size and window_size is zero. Check bios_size and window_size after
MIN operation to prevent error.

TEST=Built and boot up to kernel.

Change-Id: Ifc3f3da52d129ef5d6063a46b045603a236be759
Signed-off-by: John Zhao 
Reviewed-on: https://review.coreboot.org/c/coreboot/+/32924
Tested-by: build bot (Jenkins) 
Reviewed-by: Duncan Laurie 
---
M src/soc/intel/common/block/fast_spi/fast_spi.c
M src/soc/intel/common/block/lpc/lpc_lib.c
2 files changed, 5 insertions(+), 3 deletions(-)

Approvals:
  build bot (Jenkins): Verified
  Duncan Laurie: Looks good to me, approved

diff --git a/src/soc/intel/common/block/fast_spi/fast_spi.c b/src/soc/intel/common/block/fast_spi/fast_spi.c
index 455b13c..58e7db7 100644
--- a/src/soc/intel/common/block/fast_spi/fast_spi.c
+++ b/src/soc/intel/common/block/fast_spi/fast_spi.c
@@ -236,14 +236,13 @@
    /* Only the IFD BIOS region is memory mapped (at top of 4G) */
    fast_spi_get_bios_region(&bios_size);

-	if (!bios_size)
-		return;
-
    /* LOCAL APIC default address is 0xFEE0000, bios_size over 16MB will
     * cause memory type conflict when setting memory type to write
     * protection, so limit the cached bios region to be no more than 16MB.
     * */
    bios_size = MIN(bios_size, 16 * MiB);
+	if (!bios_size)
+		return;

/* Round to power of two */
    alignment = 1UL << (log2_ceil(bios_size));
diff --git a/src/soc/intel/common/block/lpc/lpc_lib.c b/src/soc/intel/common/block/lpc/lpc_lib.c
index b383637..c67c435 100644
--- a/src/soc/intel/common/block/lpc/lpc_lib.c
+++ b/src/soc/intel/common/block/lpc/lpc_lib.c
@@ -80,6 +80,9 @@
    	/* Each IO range register can only open a 256-byte window. */
    	window_size = MIN(size, LPC_LGIR_MAX_WINDOW_SIZE);

+		if (!window_size)
+			return;
+
    	/* Window size must be a power of two for the AMASK to work. */
    	alignment = 1UL << (log2_ceil(window_size));
    	window_size = ALIGN_UP(window_size, alignment);