[PATCH v4 21/45] Input: libps2: mark data received in __ps2_command() as initialized

Alexander Potapenko
2022-07-01T14:26:52Z

KMSAN does not know that the device initializes certain bytes in
ps2dev->cmdbuf. Call kmsan_unpoison_memory() to explicitly mark them as
initialized.

Signed-off-by: Alexander Potapenko <glider@google.com>
---
Link: https://linux-review.googlesource.com/id/I2d26f6baa45271d37320d3f4a528c39cb7e545f0
---
drivers/input/serio/libps2.c | 5 ++++-
1 file changed, 4 insertions(+), 1 deletion(-)

diff --git a/drivers/input/serio/libps2.c b/drivers/input/serio/libps2.c
index 250e213cc80c6..3e19344eda93c 100644
--- a/drivers/input/serio/libps2.c
+++ b/drivers/input/serio/libps2.c
@@ -12,6 +12,7 @@
#include <linux/sched.h>
#include <linux/interrupt.h>
#include <linux/input.h>
+#include <linux/kmsan-checks.h>
#include <linux/serio.h>
#include <linux/i8042.h>
#include <linux/libps2.h>
@@ -294,9 +295,11 @@ int __ps2_command(struct ps2dev *ps2dev, u8 *param, unsigned int command)

serio_pause_rx(ps2dev->serio);

- if (param)
+ if (param) {
for (i = 0; i < receive; i++)
param[i] = ps2dev->cmdbuf[(receive - 1) - i];
+ kmsan_unpoison_memory(param, receive);
+ }

if (ps2dev->cmdcnt &&
(command != PS2_CMD_RESET_BAT || ps2dev->cmdcnt != 1)) {
--
2.37.0.rc0.161.g10f37bed90-goog