Bluetooth: MGMT: Fix OOB access in parse_adv_monitor_pattern()

In the Linux kernel, the following vulnerability has been resolved: Bluetooth: MGMT: Fix OOB access in parse_adv_monitor_pattern() In the parse_adv_monitor_pattern() function, the value of the 'length' variable is currently limited to HCI_MAX_EXT_AD_LENGTH(251). The size of the 'value' array in the mgmt_adv_pattern structure is 31. If the value of 'pattern[i].length' is set in the user space and exceeds 31, the 'patterns[i].value' array can be accessed out of bound when copied. Increasing the size of the 'value' array in the 'mgmt_adv_pattern' structure will break the userspace. Considering this, and to avoid OOB access revert the limits for 'offset' and 'length' back to the value of HCI_MAX_AD_LENGTH. Found by InfoTeCS on behalf of Linux Verification Center (linuxtesting.org) with SVACE.