[PATCH 8/8] Input: input_event: fix struct padding on sparc64

From: Arnd Bergmann
Date: Fri Nov 08 2019 - 15:38:01 EST


Going through all uses of timeval, I noticed that we screwed up
input_event in the previous attempts to fix it:

The time fields now match between kernel and user space, but
all following fields are in the wrong place.

Add the required padding that is implied by the glibc timeval
definition to fix the layout, and add explicit initialization
to avoid leaking kernel stack data.

Cc: sparclinux@xxxxxxxxxxxxxxx
Cc: "David S. Miller" <davem@xxxxxxxxxxxxx>
Cc: stable@xxxxxxxxxxxxxxx
Fixes: 141e5dcaa735 ("Input: input_event - fix the CONFIG_SPARC64 mixup")
Fixes: 2e746942ebac ("Input: input_event - provide override for sparc64")
Signed-off-by: Arnd Bergmann <arnd@xxxxxxxx>
---
drivers/input/evdev.c | 3 +++
drivers/input/misc/uinput.c | 3 +++
include/uapi/linux/input.h | 1 +
3 files changed, 7 insertions(+)

diff --git a/drivers/input/evdev.c b/drivers/input/evdev.c
index d7dd6fcf2db0..24a90793caf0 100644
--- a/drivers/input/evdev.c
+++ b/drivers/input/evdev.c
@@ -228,6 +228,9 @@ static void __pass_event(struct evdev_client *client,
event->input_event_sec;
client->buffer[client->tail].input_event_usec =
event->input_event_usec;
+#ifdef CONFIG_SPARC64
+ client->buffer[client->tail].__pad = 0;
+#endif
client->buffer[client->tail].type = EV_SYN;
client->buffer[client->tail].code = SYN_DROPPED;
client->buffer[client->tail].value = 0;
diff --git a/drivers/input/misc/uinput.c b/drivers/input/misc/uinput.c
index 84051f20b18a..1d8c09e9fd47 100644
--- a/drivers/input/misc/uinput.c
+++ b/drivers/input/misc/uinput.c
@@ -80,6 +80,9 @@ static int uinput_dev_event(struct input_dev *dev,
ktime_get_ts64(&ts);
udev->buff[udev->head].input_event_sec = ts.tv_sec;
udev->buff[udev->head].input_event_usec = ts.tv_nsec / NSEC_PER_USEC;
+#ifdef CONFIG_SPARC64
+ udev->buff[udev->head].__pad = 0;
+#endif
udev->head = (udev->head + 1) % UINPUT_BUFFER_SIZE;

wake_up_interruptible(&udev->waitq);
diff --git a/include/uapi/linux/input.h b/include/uapi/linux/input.h
index f056b2a00d5c..9a61c28ed3ae 100644
--- a/include/uapi/linux/input.h
+++ b/include/uapi/linux/input.h
@@ -34,6 +34,7 @@ struct input_event {
__kernel_ulong_t __sec;
#if defined(__sparc__) && defined(__arch64__)
unsigned int __usec;
+ unsigned int __pad;
#else
__kernel_ulong_t __usec;
#endif
--
2.20.0