libusb0/1: Simplify range checks in nut API nut_libusb_get_string()

The string index is a number between 1 and 255, simply because it is the lower byte of wValue in the GET_DESCRIPTOR request. String index 0 is used for retrieving the langid array, so it is not valid for this function. There is no reason to impose a limit to the length of the buffer that the user is lending us, certainly not above the range of the involved types, so just a minimal sanity check is enough. Since in the minimal case we would return an empty zero-terminated string, it must at least have room for this. Signed-off-by: Tormod Volden <[email protected]>
networkupstools · Aug 28, 2024 · 03c1ea7 · 03c1ea7
1 parent f3ebe44
commit 03c1ea7
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Showing 2 changed files with 3 additions and 36 deletions.
diff --git a/drivers/libusb0.c b/drivers/libusb0.c
@@ -863,29 +863,14 @@ static int libusb_get_string(
 {
 	int ret;
 
-#if (defined HAVE_PRAGMA_GCC_DIAGNOSTIC_PUSH_POP) && ( (defined HAVE_PRAGMA_GCC_DIAGNOSTIC_IGNORED_TYPE_LIMITS) || (defined HAVE_PRAGMA_GCC_DIAGNOSTIC_IGNORED_TAUTOLOGICAL_CONSTANT_OUT_OF_RANGE_COMPARE) || (defined HAVE_PRAGMA_GCC_DIAGNOSTIC_IGNORED_TAUTOLOGICAL_UNSIGNED_ZERO_COMPARE) )
-# pragma GCC diagnostic push
-#endif
-#ifdef HAVE_PRAGMA_GCC_DIAGNOSTIC_IGNORED_TYPE_LIMITS
-# pragma GCC diagnostic ignored "-Wtype-limits"
-#endif
-#ifdef HAVE_PRAGMA_GCC_DIAGNOSTIC_IGNORED_TAUTOLOGICAL_CONSTANT_OUT_OF_RANGE_COMPARE
-# pragma GCC diagnostic ignored "-Wtautological-constant-out-of-range-compare"
-#endif
-#ifdef HAVE_PRAGMA_GCC_DIAGNOSTIC_IGNORED_TAUTOLOGICAL_UNSIGNED_ZERO_COMPARE
-# pragma GCC diagnostic ignored "-Wtautological-unsigned-zero-compare"
-#endif
 	/*
 	 * usb.h:int  nut_usb_get_string(usb_dev_handle *dev, int index,
 	 * usb.h-         char *buf, size_t buflen);
 	 */
 	if (!udev
-	|| StringIdx < 0 || (uintmax_t)StringIdx > INT_MAX
-	|| buflen < 0 || (uintmax_t)buflen > (uintmax_t)SIZE_MAX
+	|| StringIdx < 1 || StringIdx > 255
+	|| buflen < 1
 	) {
-#if (defined HAVE_PRAGMA_GCC_DIAGNOSTIC_PUSH_POP) && ( (defined HAVE_PRAGMA_GCC_DIAGNOSTIC_IGNORED_TYPE_LIMITS) || (defined HAVE_PRAGMA_GCC_DIAGNOSTIC_IGNORED_TAUTOLOGICAL_CONSTANT_OUT_OF_RANGE_COMPARE) || (defined HAVE_PRAGMA_GCC_DIAGNOSTIC_IGNORED_TAUTOLOGICAL_UNSIGNED_ZERO_COMPARE) )
-# pragma GCC diagnostic pop
-#endif
 		return -1;
 	}
 

diff --git a/drivers/libusb1.c b/drivers/libusb1.c
@@ -985,25 +985,7 @@ static int nut_libusb_get_string(
 {
 	int ret;
 
-#if (defined HAVE_PRAGMA_GCC_DIAGNOSTIC_PUSH_POP) && ( (defined HAVE_PRAGMA_GCC_DIAGNOSTIC_IGNORED_TYPE_LIMITS) || (defined HAVE_PRAGMA_GCC_DIAGNOSTIC_IGNORED_TAUTOLOGICAL_CONSTANT_OUT_OF_RANGE_COMPARE) || (defined HAVE_PRAGMA_GCC_DIAGNOSTIC_IGNORED_TAUTOLOGICAL_UNSIGNED_ZERO_COMPARE) )
-# pragma GCC diagnostic push
-#endif
-#ifdef HAVE_PRAGMA_GCC_DIAGNOSTIC_IGNORED_TYPE_LIMITS
-# pragma GCC diagnostic ignored "-Wtype-limits"
-#endif
-#ifdef HAVE_PRAGMA_GCC_DIAGNOSTIC_IGNORED_TAUTOLOGICAL_CONSTANT_OUT_OF_RANGE_COMPARE
-# pragma GCC diagnostic ignored "-Wtautological-constant-out-of-range-compare"
-#endif
-#ifdef HAVE_PRAGMA_GCC_DIAGNOSTIC_IGNORED_TAUTOLOGICAL_UNSIGNED_ZERO_COMPARE
-# pragma GCC diagnostic ignored "-Wtautological-unsigned-zero-compare"
-#endif
-	if (!udev
-	|| StringIdx < 0 || (uintmax_t)StringIdx > UINT8_MAX
-	|| buflen < 0 || (uintmax_t)buflen > (uintmax_t)INT_MAX
-	) {
-#if (defined HAVE_PRAGMA_GCC_DIAGNOSTIC_PUSH_POP) && ( (defined HAVE_PRAGMA_GCC_DIAGNOSTIC_IGNORED_TYPE_LIMITS) || (defined HAVE_PRAGMA_GCC_DIAGNOSTIC_IGNORED_TAUTOLOGICAL_CONSTANT_OUT_OF_RANGE_COMPARE) || (defined HAVE_PRAGMA_GCC_DIAGNOSTIC_IGNORED_TAUTOLOGICAL_UNSIGNED_ZERO_COMPARE) )
-# pragma GCC diagnostic pop
-#endif
+	if (!udev || StringIdx < 1 || buflen < 1) {
 		return -1;
 	}