diff options
| author | Dmitry Torokhov <dmitry.torokhov@gmail.com> | 2024-10-03 07:46:50 -0700 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2025-09-09 18:58:04 +0200 |
| commit | 7a7ba33110698166b488a06cdc04a16ca3dba176 (patch) | |
| tree | cae946b97bedefffc3c4e099bab2f6577386c89f | |
| parent | a905edfec7447e575ebbebc2535e854cefa4cf1c (diff) | |
HID: simplify snto32()
[ Upstream commit ae9b956cb26c0fd5a365629f2d723ab2fb14df79 ]
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@gmail.com>
Link: https://patch.msgid.link/20241003144656.3786064-1-dmitry.torokhov@gmail.com
Signed-off-by: Benjamin Tissoires <bentiss@kernel.org>
Stable-dep-of: a6b87bfc2ab5 ("HID: core: Harden s32ton() against conversion to 0 bits")
Signed-off-by: Sasha Levin <sashal@kernel.org>
| -rw-r--r-- | drivers/hid/hid-core.c | 11 |
1 files changed, 2 insertions, 9 deletions
diff --git a/drivers/hid/hid-core.c b/drivers/hid/hid-core.c index c2783d04c6e0..1a8e88624acf 100644 --- a/drivers/hid/hid-core.c +++ b/drivers/hid/hid-core.c @@ -1318,9 +1318,7 @@ alloc_err: 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) @@ -1331,12 +1329,7 @@ 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) |