HID: roccat: prevent an out of bounds read in kovaplus_profile_activated()

commit 7ad81482cad67cbe1ec808490d1ddfc420c42008 upstream.

We get the "new_profile_index" value from the mouse device when we're
handling raw events.  Smatch taints it as untrusted data and complains
that we need a bounds check.  This seems like a reasonable warning
otherwise there is a small read beyond the end of the array.

Fixes: 0e70f97f257e ("HID: roccat: Add support for Kova[+] mouse")
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Acked-by: Silvan Jegen <s.jegen@gmail.com>
Signed-off-by: Jiri Kosina <jkosina@suse.cz>
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>

diff --git a/drivers/hid/hid-roccat-kovaplus.c b/drivers/hid/hid-roccat-kovaplus.c
index 112d934..3d37c89 100644 (file)
--- a/drivers/hid/hid-roccat-kovaplus.c
+++ b/drivers/hid/hid-roccat-kovaplus.c
@@ -37,6 +37,8 @@ static uint kovaplus_convert_event_cpi(uint value)
 static void kovaplus_profile_activated(struct kovaplus_device *kovaplus,
                uint new_profile_index)
 {
 static void kovaplus_profile_activated(struct kovaplus_device *kovaplus,
                uint new_profile_index)
 {

+       if (new_profile_index >= ARRAY_SIZE(kovaplus->profile_settings))
+               return;

        kovaplus->actual_profile = new_profile_index;
        kovaplus->actual_cpi = kovaplus->profile_settings[new_profile_index].cpi_startup_level;
        kovaplus->actual_x_sensitivity = kovaplus->profile_settings[new_profile_index].sensitivity_x;
        kovaplus->actual_profile = new_profile_index;
        kovaplus->actual_cpi = kovaplus->profile_settings[new_profile_index].cpi_startup_level;
        kovaplus->actual_x_sensitivity = kovaplus->profile_settings[new_profile_index].sensitivity_x;