1 files changed, 27 insertions, 17 deletions

diff --git a/drivers/acpi/utilities/utmisc.c b/drivers/acpi/utilities/utmisc.c
index 4d32f6d18f648..f6598547389b8 100644
--- a/drivers/acpi/utilities/utmisc.c
+++ b/drivers/acpi/utilities/utmisc.c
@@ -372,7 +372,7 @@ acpi_ut_strtoul64 (
 	u32                             base,
 	acpi_integer                    *ret_integer)
 {
-	u32                             this_digit;
+	u32                             this_digit = 0;
 	acpi_integer                    return_value = 0;
 	acpi_integer                    quotient;
 
@@ -380,6 +380,10 @@ acpi_ut_strtoul64 (
 	ACPI_FUNCTION_TRACE ("ut_stroul64");
 
 
+	if ((!string) || !(*string)) {
+		goto error_exit;
+	}
+
 	switch (base) {
 	case ACPI_ANY_BASE:
 	case 10:
@@ -394,7 +398,7 @@ acpi_ut_strtoul64 (
 	/* Skip over any white space in the buffer */
 
 	while (ACPI_IS_SPACE (*string) || *string == '\t') {
-		++string;
+		string++;
 	}
 
 	/*
@@ -403,9 +407,9 @@ acpi_ut_strtoul64 (
 	 */
 	if (base == 0) {
 		if ((*string == '0') &&
-			(ACPI_TOLOWER (*(++string)) == 'x')) {
+			(ACPI_TOLOWER (*(string + 1)) == 'x')) {
 			base = 16;
-			++string;
+			string += 2;
 		}
 		else {
 			base = 10;
@@ -416,10 +420,10 @@ acpi_ut_strtoul64 (
 	 * For hexadecimal base, skip over the leading
 	 * 0 or 0x, if they are present.
 	 */
-	if (base == 16 &&
-		*string == '0' &&
-		ACPI_TOLOWER (*(++string)) == 'x') {
-		string++;
+	if ((base == 16) &&
+		(*string == '0') &&
+		(ACPI_TOLOWER (*(string + 1)) == 'x')) {
+		string += 2;
 	}
 
 	/* Any string left? */
@@ -437,23 +441,27 @@ acpi_ut_strtoul64 (
 			this_digit = ((u8) *string) - '0';
 		}
 		else {
+			if (base == 10) {
+				/* Digit is out of range */
+
+				goto error_exit;
+			}
+
 			this_digit = (u8) ACPI_TOUPPER (*string);
-			if (ACPI_IS_UPPER ((char) this_digit)) {
+			if (ACPI_IS_XDIGIT ((char) this_digit)) {
 				/* Convert ASCII Hex char to value */
 
 				this_digit = this_digit - 'A' + 10;
 			}
 			else {
-				goto error_exit;
+				/*
+				 * We allow non-hex chars, just stop now, same as end-of-string.
+				 * See ACPI spec, string-to-integer conversion.
+				 */
+				break;
 			}
 		}
 
-		/* Check to see if digit is out of range */
-
-		if (this_digit >= base) {
-			goto error_exit;
-		}
-
 		/* Divide the digit into the correct position */
 
 		(void) acpi_ut_short_divide ((ACPI_INTEGER_MAX - (acpi_integer) this_digit),
@@ -464,9 +472,11 @@ acpi_ut_strtoul64 (
 
 		return_value *= base;
 		return_value += this_digit;
-		++string;
+		string++;
 	}
 
+	/* All done, normal exit */
+
 	*ret_integer = return_value;
 	return_ACPI_STATUS (AE_OK);