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	Input: joydev - prevent potential read overflow in ioctl
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: 999b874f4a ("Input: joydev - validate axis/button maps before clobbering current ones")
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Link: https://lore.kernel.org/r/YCyzR8WvFRw4HWw6@mwanda
[dtor: additional check for len being even in joydev_handle_JSIOCSBTNMAP]
Cc: stable@vger.kernel.org
Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>
			
			
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					 1 changed files with 5 additions and 2 deletions
				
			
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			@ -456,7 +456,7 @@ static int joydev_handle_JSIOCSAXMAP(struct joydev *joydev,
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	if (IS_ERR(abspam))
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		return PTR_ERR(abspam);
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	for (i = 0; i < joydev->nabs; i++) {
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	for (i = 0; i < len && i < joydev->nabs; i++) {
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		if (abspam[i] > ABS_MAX) {
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			retval = -EINVAL;
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			goto out;
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			@ -480,6 +480,9 @@ static int joydev_handle_JSIOCSBTNMAP(struct joydev *joydev,
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	int i;
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	int retval = 0;
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	if (len % sizeof(*keypam))
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		return -EINVAL;
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	len = min(len, sizeof(joydev->keypam));
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	/* Validate the map. */
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			@ -487,7 +490,7 @@ static int joydev_handle_JSIOCSBTNMAP(struct joydev *joydev,
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	if (IS_ERR(keypam))
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		return PTR_ERR(keypam);
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	for (i = 0; i < joydev->nkey; i++) {
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	for (i = 0; i < (len / 2) && i < joydev->nkey; i++) {
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		if (keypam[i] > KEY_MAX || keypam[i] < BTN_MISC) {
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			retval = -EINVAL;
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			goto out;
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