[lvc-project] [PATCH] Input: cypress_ps2 - fix cypress_ps2_sendbyte() result check

From: Igor Artemiev
Date: Mon Feb 20 2023 - 07:42:22 EST


cypress_ps2_sendbyte() returns 0 or an error code greater than 0.
The cypress_ps2_read_cmd_status() function assumes that
cypress_ps2_read_cmd_status() will return a negative value on error.

Found by Linux Verification Center (linuxtesting.org) with SVACE.

Fixes: 0799a924bc93 ("Input: add support for Cypress PS/2 Trackpads")
Signed-off-by: Igor Artemiev <Igor.A.Artemiev@xxxxxxx>
---
drivers/input/mouse/cypress_ps2.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/input/mouse/cypress_ps2.c b/drivers/input/mouse/cypress_ps2.c
index d272f1ec27ba..b170959e2ad3 100644
--- a/drivers/input/mouse/cypress_ps2.c
+++ b/drivers/input/mouse/cypress_ps2.c
@@ -114,7 +114,7 @@ static int cypress_ps2_read_cmd_status(struct psmouse *psmouse,
memset(param, 0, pktsize);

rc = cypress_ps2_sendbyte(psmouse, 0xe9);
- if (rc < 0)
+ if (rc > 0)
goto out;

wait_event_timeout(ps2dev->wait,
--
2.30.2