From: Dan Carpenter <dan.carpenter@xxxxxxxxxx>
commit 182d679b2298d62bf42bb14b12a8067b8e17b617 upstream.
The problem here is that "len" might be less than "joydev->nabs" so the
loops which verfy abspam[i] and keypam[] might read beyond the buffer.
Fixes: 999b874f4aa3 ("Input: joydev - validate axis/button maps before clobbering current ones")
Signed-off-by: Dan Carpenter <dan.carpenter@xxxxxxxxxx>
Link: https://lore.kernel.org/r/YCyzR8WvFRw4HWw6@mwanda
[dtor: additional check for len being even in joydev_handle_JSIOCSBTNMAP]
Cc: stable@xxxxxxxxxxxxxxx
Signed-off-by: Dmitry Torokhov <dmitry.torokhov@xxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
drivers/input/joydev.c | 7 +++++--
1 file changed, 5 insertions(+), 2 deletions(-)
--- a/drivers/input/joydev.c
+++ b/drivers/input/joydev.c
@@ -456,7 +456,7 @@ static int joydev_handle_JSIOCSAXMAP(str
if (IS_ERR(abspam))
return PTR_ERR(abspam);
- for (i = 0; i < joydev->nabs; i++) {
+ for (i = 0; i < len && i < joydev->nabs; i++) {
if (abspam[i] > ABS_MAX) {
retval = -EINVAL;
goto out;
@@ -480,6 +480,9 @@ static int joydev_handle_JSIOCSBTNMAP(st
int i;
int retval = 0;
+ if (len % sizeof(*keypam))
+ return -EINVAL;
+
len = min(len, sizeof(joydev->keypam));
/* Validate the map. */
@@ -487,7 +490,7 @@ static int joydev_handle_JSIOCSBTNMAP(st
if (IS_ERR(keypam))
return PTR_ERR(keypam);
- for (i = 0; i < joydev->nkey; i++) {
+ for (i = 0; i < (len / 2) && i < joydev->nkey; i++) {
if (keypam[i] > KEY_MAX || keypam[i] < BTN_MISC) {
retval = -EINVAL;
goto out;
