3.18-stable review patch. If anyone has any objections, please let me know. ------------------ From: Dan Carpenter <dan.carpenter@xxxxxxxxxx> commit 9de4ee40547fd315d4a0ed1dd15a2fa3559ad707 upstream. This cast is wrong. "cdi->capacity" is an int and "arg" is an unsigned long. The way the check is written now, if one of the high 32 bits is set then we could read outside the info->slots[] array. This bug is pretty old and it predates git. Reviewed-by: Christoph Hellwig <hch@xxxxxx> Cc: stable@xxxxxxxxxxxxxxx Signed-off-by: Dan Carpenter <dan.carpenter@xxxxxxxxxx> Signed-off-by: Jens Axboe <axboe@xxxxxxxxx> Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> --- drivers/cdrom/cdrom.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) --- a/drivers/cdrom/cdrom.c +++ b/drivers/cdrom/cdrom.c @@ -2357,7 +2357,7 @@ static int cdrom_ioctl_media_changed(str if (!CDROM_CAN(CDC_SELECT_DISC) || arg == CDSL_CURRENT) return media_changed(cdi, 1); - if ((unsigned int)arg >= cdi->capacity) + if (arg >= cdi->capacity) return -EINVAL; info = kmalloc(sizeof(*info), GFP_KERNEL);