snto32() does exactly what sign_extend32() does, but handles
potentially malformed data coming from the device. Keep the checks,
but then call sign_extend32() to perform the actual conversion.
Signed-off-by: Dmitry Torokhov <dmitry.torokhov@xxxxxxxxx>
---
drivers/hid/hid-core.c | 11 ++---------
1 file changed, 2 insertions(+), 9 deletions(-)
diff --git a/drivers/hid/hid-core.c b/drivers/hid/hid-core.c
index 00942d40fe08..5f62df91030d 100644
--- a/drivers/hid/hid-core.c
+++ b/drivers/hid/hid-core.c
@@ -1313,9 +1313,7 @@ int hid_open_report(struct hid_device *device)
EXPORT_SYMBOL_GPL(hid_open_report);
/*
- * Convert a signed n-bit integer to signed 32-bit integer. Common
- * cases are done through the compiler, the screwed things has to be
- * done by hand.
+ * Convert a signed n-bit integer to signed 32-bit integer.
*/
static s32 snto32(__u32 value, unsigned n)
@@ -1326,12 +1324,7 @@ static s32 snto32(__u32 value, unsigned n)
if (n > 32)
n = 32;
- switch (n) {
- case 8: return ((__s8)value);
- case 16: return ((__s16)value);
- case 32: return ((__s32)value);
- }
- return value & (1 << (n - 1)) ? value | (~0U << n) : value;
+ return sign_extend32(value, n - 1);
}
s32 hid_snto32(__u32 value, unsigned n)
--
2.47.0.rc0.187.ge670bccf7e-goog
