Input: joydev - fix possible ERR_PTR() dereferencing

Commit 5702222c9a ("Input: joydev - use memdup_user() to duplicate
memory from user-space") changed the kmalloc() and copy_from_user()
with a single call to memdup_user() but wrongly used the same error
path than the old code in which the buffer allocated by kmalloc() was
freed if copy_from_user() failed.

This is of course wrong since if memdup_user() fails, no memory was
allocated and the error in the error-valued pointer should be returned.

Fixes: 5702222c9a ("Input: joydev - use memdup_user() to duplicate
memory from user-space")
Reported-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Javier Martinez Canillas <javier@osg.samsung.com>
Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>
This commit is contained in:
Javier Martinez Canillas 2015-10-06 15:23:36 -07:00 committed by Dmitry Torokhov
parent c7efd12350
commit 5b21e3c740

View File

@ -445,10 +445,8 @@ static int joydev_handle_JSIOCSAXMAP(struct joydev *joydev,
/* Validate the map. */
abspam = memdup_user(argp, len);
if (IS_ERR(abspam)) {
retval = PTR_ERR(abspam);
goto out;
}
if (IS_ERR(abspam))
return PTR_ERR(abspam);
for (i = 0; i < joydev->nabs; i++) {
if (abspam[i] > ABS_MAX) {
@ -478,10 +476,8 @@ static int joydev_handle_JSIOCSBTNMAP(struct joydev *joydev,
/* Validate the map. */
keypam = memdup_user(argp, len);
if (IS_ERR(keypam)) {
retval = PTR_ERR(keypam);
goto out;
}
if (IS_ERR(keypam))
return PTR_ERR(keypam);
for (i = 0; i < joydev->nkey; i++) {
if (keypam[i] > KEY_MAX || keypam[i] < BTN_MISC) {