Bluetooth: MGMT: Fix status of pending commands flushed on power off
Impact
In the Linux kernel, the following vulnerability has been resolved:
Source excerpt · LinuxAffected packages
Affected products
Vendor version evidence. Product records are separate from automatic dependency matching.
Linux · Linux
Other versions: unaffected
| Version / range | Source status |
|---|---|
| 4883296505aa7e4863c6869b689afb6005633b23 to before 44ce36c5789ac84e65de1e98c32db9a5ac04ed47 | affected |
| f53e1c9c726d83092167f2226f32bd3b73f26c21 to before 7ed7e038b520cf0dfa12d61c2caddb95e2f6922d | affected |
| f53e1c9c726d83092167f2226f32bd3b73f26c21 to before ec227cddd13cd7ac9077d263a73473ac370a055d | affected |
| f53e1c9c726d83092167f2226f32bd3b73f26c21 to before 07976405a3c71253e50533ee7b7a8b0dc16ab6ba | affected |
| f53e1c9c726d83092167f2226f32bd3b73f26c21 to before 86ef0f58bdecdedb3a1240971c56d71b7e4ce3fc | affected |
| 19b40ca62607cef78369549d1af091f2fd558931 | affected |
| 0cc47233af35fb5f10b5e6a027cb4ccd480caf9a | affected |
| 8c3f7943a29145d8a2d8e24893762f7673323eae | affected |
| 6.6.55 to before 6.6.160 | affected |
| 6.1.120 to before 6.2 | affected |
| 6.10.14 to before 6.11 | affected |
| 6.11.3 to before 6.12 | affected |
Linux · Linux
Other versions: affected
| Version / range | Source status |
|---|---|
| 6.12 | affected |
| 0 to before 6.12 | unaffected |
| 6.6.160 through 6.6.* (inclusive) | unaffected |
| 6.12.113 through 6.12.* (inclusive) | unaffected |
| 6.18.57 through 6.18.* (inclusive) | unaffected |
| 7.2.11 through 7.2.* (inclusive) | unaffected |
| 7.3 through * (inclusive) | unaffected |
Original source description
In the Linux kernel, the following vulnerability has been resolved:
Bluetooth: MGMT: Fix status of pending commands flushed on power off
cmd_complete_rsp() receives a struct cmd_lookup and, for a pending command that has no cmd_complete callback, falls through to cmd_status_rsp(cmd, data). cmd_status_rsp() reads data as a u8 *, so the status sent comes from the first byte of match->sk's representation, not from match->mgmt_status.
commit f53e1c9c726d ("Bluetooth: MGMT: Fix possible crash on mgmt_index_removed") changed the callers' data from &status to &match and updated the cmd_complete branch to match->mgmt_status, but left the fall-through passing data unchanged.
In mgmt_index_removed() match->sk is NULL, so every such command is answered with status 0x00 (Success) instead of MGMT_STATUS_INVALID_INDEX. In __mgmt_power_off() it is NULL too, unless a Set Powered command was pending: then settings_rsp() has stored that command's socket in match->sk, and the byte sent comes from the socket pointer. Either way the status the caller set, MGMT_STATUS_NOT_POWERED (or MGMT_STATUS_INVALID_INDEX when the device is being unregistered), is lost.
Pass the status the callers set.
This was seen on a QCA9377 laptop: bluetoothd's Start Discovery, pending when the adapter was powered off, was answered with Command Status 0x00 and no parameters, and bluetoothd 5.72 crashed on the zero-length success. BlueZ master has since added the length check on that path ("adapter: Fix crash on short start discovery reply", BlueZ a734b06059cb), but userspace should still be told Not Powered, not Success.
Tested on Ubuntu 7.0.0-31 with a virtual controller (hci_vhci): power off is held in HCI Write Scan Enable while a Start Discovery is submitted, and the flush answers it with status 0x00 before this change and 0x0f (Not Powered) after.
References
- Source reference git.kernel.org/stable/c/44ce36c5789ac84e65de1e98c32db9a5ac04ed47
- Source reference git.kernel.org/stable/c/7ed7e038b520cf0dfa12d61c2caddb95e2f6922d
- Source reference git.kernel.org/stable/c/ec227cddd13cd7ac9077d263a73473ac370a055d
- Source reference git.kernel.org/stable/c/07976405a3c71253e50533ee7b7a8b0dc16ab6ba
- Source reference git.kernel.org/stable/c/86ef0f58bdecdedb3a1240971c56d71b7e4ce3fc