Commit 4a798f50 authored Mar 18, 2016 by Colin Ian King Committed by Rafael J. Wysocki Mar 22, 2016

ACPI / util: cast data to u64 before shifting to fix sign extension



obj->buffer.pointer[i] should be cast to u64 to prevent an unintentional
sign extension.  For example, if pointer[7] is 0x80, then the value
0xffffffffff000000 is or'd into mask rather than the intended value
0xff00000000000000

Detected with static analysis by CoverityScan

Signed-off-by: Colin Ian King <colin.king@canonical.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>

parent bea3c377

drivers/acpi/utils.c

+1 −1

Original line number	Diff line number	Diff line
		@@ -692,7 +692,7 @@ bool acpi_check_dsm(acpi_handle handle, const u8 *uuid, int rev, u64 funcs)
		mask = obj->integer.value;
		else if (obj->type == ACPI_TYPE_BUFFER)
		for (i = 0; i < obj->buffer.length && i < 8; i++)
		mask \|= (((u8)obj->buffer.pointer[i]) << (i * 8));
		mask \|= (((u64)obj->buffer.pointer[i]) << (i * 8));
		ACPI_FREE(obj);

		/*

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