kernel/net/bluetooth, branch linux-5.10.y

Bluetooth: L2CAP: Fix missing key size check for L2CAP_LE_CONN_REQ

2026-03-04T12:20:11Z

[ Upstream commit 138d7eca445ef37a0333425d269ee59900ca1104 ] This adds a check for encryption key size upon receiving L2CAP_LE_CONN_REQ which is required by L2CAP/LE/CFC/BV-15-C which expects L2CAP_CR_LE_BAD_KEY_SIZE. Link: https://lore.kernel.org/linux-bluetooth/5782243.rdbgypaU67@n9w6sw14/ Fixes: 27e2d4c8d28b ("Bluetooth: Add basic LE L2CAP connect request receiving support") Signed-off-by: Luiz Augusto von Dentz Tested-by: Christian Eggers Signed-off-by: Sasha Levin

Bluetooth: L2CAP: Fix not checking l2cap_chan security level

2026-03-04T12:20:11Z

[ Upstream commit 7af8479d9eb4319b4ba7b47a8c4d2c55af1c31e1 ] l2cap_check_enc_key_size shall check the security level of the l2cap_chan rather than the hci_conn since for incoming connection request that may be different as hci_conn may already been encrypted using a different security level. Fixes: 522e9ed157e3 ("Bluetooth: l2cap: Check encryption key size on incoming connection") Signed-off-by: Luiz Augusto von Dentz Stable-dep-of: 138d7eca445e ("Bluetooth: L2CAP: Fix missing key size check for L2CAP_LE_CONN_REQ") Signed-off-by: Sasha Levin

Bluetooth: l2cap: Check encryption key size on incoming connection

2026-03-04T12:20:11Z

[ Upstream commit 522e9ed157e3c21b4dd623c79967f72c21e45b78 ] This is required for passing GAP/SEC/SEM/BI-04-C PTS test case: Security Mode 4 Level 4, Responder - Invalid Encryption Key Size - 128 bit This tests the security key with size from 1 to 15 bytes while the Security Mode 4 Level 4 requests 16 bytes key size. Currently PTS fails with the following logs: - expected:Connection Response: Code: [3 (0x03)] Code Identifier: (lt)WildCard: Exists(gt) Length: [8 (0x0008)] Destination CID: (lt)WildCard: Exists(gt) Source CID: [64 (0x0040)] Result: [3 (0x0003)] Connection refused - Security block Status: (lt)WildCard: Exists(gt), but received:Connection Response: Code: [3 (0x03)] Code Identifier: [1 (0x01)] Length: [8 (0x0008)] Destination CID: [64 (0x0040)] Source CID: [64 (0x0040)] Result: [0 (0x0000)] Connection Successful Status: [0 (0x0000)] No further information available And HCI logs: < HCI Command: Read Encrypti.. (0x05|0x0008) plen 2 Handle: 14 Address: 00:1B:DC:F2:24:10 (Vencer Co., Ltd.) > HCI Event: Command Complete (0x0e) plen 7 Read Encryption Key Size (0x05|0x0008) ncmd 1 Status: Success (0x00) Handle: 14 Address: 00:1B:DC:F2:24:10 (Vencer Co., Ltd.) Key size: 7 > ACL Data RX: Handle 14 flags 0x02 dlen 12 L2CAP: Connection Request (0x02) ident 1 len 4 PSM: 4097 (0x1001) Source CID: 64 < ACL Data TX: Handle 14 flags 0x00 dlen 16 L2CAP: Connection Response (0x03) ident 1 len 8 Destination CID: 64 Source CID: 64 Result: Connection successful (0x0000) Status: No further information available (0x0000) Fixes: 288c06973daa ("Bluetooth: Enforce key size of 16 bytes on FIPS level") Signed-off-by: Frédéric Danis Signed-off-by: Luiz Augusto von Dentz Stable-dep-of: 138d7eca445e ("Bluetooth: L2CAP: Fix missing key size check for L2CAP_LE_CONN_REQ") Signed-off-by: Sasha Levin

Bluetooth: Enforce key size of 16 bytes on FIPS level

2026-03-04T12:20:10Z

[ Upstream commit 288c06973daae4637f25a0d1bdaf65fdbf8455f9 ] According to the spec Ver 5.2, Vol 3, Part C, Sec 5.2.2.8: Device in security mode 4 level 4 shall enforce: 128-bit equivalent strength for link and encryption keys required using FIPS approved algorithms (E0 not allowed, SAFER+ not allowed, and P-192 not allowed; encryption key not shortened) This patch rejects connection with key size below 16 for FIPS level services. Signed-off-by: Archie Pusaka Reviewed-by: Alain Michaud Signed-off-by: Marcel Holtmann Stable-dep-of: 138d7eca445e ("Bluetooth: L2CAP: Fix missing key size check for L2CAP_LE_CONN_REQ") Signed-off-by: Sasha Levin

Bluetooth: L2CAP: Fix response to L2CAP_ECRED_CONN_REQ

2026-03-04T12:20:10Z

[ Upstream commit 05761c2c2b5bfec85c47f60c903c461e9b56cf87 ] Similar to 03dba9cea72f ("Bluetooth: L2CAP: Fix not responding with L2CAP_CR_LE_ENCRYPTION") the result code L2CAP_CR_LE_ENCRYPTION shall be used when BT_SECURITY_MEDIUM is set since that means security mode 2 which mean it doesn't require authentication which results in qualification test L2CAP/ECFC/BV-32-C failing. Link: https://github.com/bluez/bluez/issues/1871 Fixes: 15f02b910562 ("Bluetooth: L2CAP: Add initial code for Enhanced Credit Based Mode") Signed-off-by: Luiz Augusto von Dentz Signed-off-by: Sasha Levin

Bluetooth: L2CAP: Fix invalid response to L2CAP_ECRED_RECONF_REQ

2026-03-04T12:20:10Z

[ Upstream commit 7accb1c4321acb617faf934af59d928b0b047e2b ] This fixes responding with an invalid result caused by checking the wrong size of CID which should have been (cmd_len - sizeof(*req)) and on top of it the wrong result was use L2CAP_CR_LE_INVALID_PARAMS which is invalid/reserved for reconf when running test like L2CAP/ECFC/BI-03-C: > ACL Data RX: Handle 64 flags 0x02 dlen 14 LE L2CAP: Enhanced Credit Reconfigure Request (0x19) ident 2 len 6 MTU: 64 MPS: 64 Source CID: 64 < ACL Data TX: Handle 64 flags 0x00 dlen 10 LE L2CAP: Enhanced Credit Reconfigure Respond (0x1a) ident 2 len 2 ! Result: Reserved (0x000c) Result: Reconfiguration failed - one or more Destination CIDs invalid (0x0003) Fiix L2CAP/ECFC/BI-04-C which expects L2CAP_RECONF_INVALID_MPS (0x0002) when more than one channel gets its MPS reduced: > ACL Data RX: Handle 64 flags 0x02 dlen 16 LE L2CAP: Enhanced Credit Reconfigure Request (0x19) ident 2 len 8 MTU: 264 MPS: 99 Source CID: 64 ! Source CID: 65 < ACL Data TX: Handle 64 flags 0x00 dlen 10 LE L2CAP: Enhanced Credit Reconfigure Respond (0x1a) ident 2 len 2 ! Result: Reconfiguration successful (0x0000) Result: Reconfiguration failed - reduction in size of MPS not allowed for more than one channel at a time (0x0002) Fix L2CAP/ECFC/BI-05-C when SCID is invalid (85 unconnected): > ACL Data RX: Handle 64 flags 0x02 dlen 14 LE L2CAP: Enhanced Credit Reconfigure Request (0x19) ident 2 len 6 MTU: 65 MPS: 64 ! Source CID: 85 < ACL Data TX: Handle 64 flags 0x00 dlen 10 LE L2CAP: Enhanced Credit Reconfigure Respond (0x1a) ident 2 len 2 ! Result: Reconfiguration successful (0x0000) Result: Reconfiguration failed - one or more Destination CIDs invalid (0x0003) Fix L2CAP/ECFC/BI-06-C when MPS < L2CAP_ECRED_MIN_MPS (64): > ACL Data RX: Handle 64 flags 0x02 dlen 14 LE L2CAP: Enhanced Credit Reconfigure Request (0x19) ident 2 len 6 MTU: 672 ! MPS: 63 Source CID: 64 < ACL Data TX: Handle 64 flags 0x00 dlen 10 LE L2CAP: Enhanced Credit Reconfigure Respond (0x1a) ident 2 len 2 ! Result: Reconfiguration failed - reduction in size of MPS not allowed for more than one channel at a time (0x0002) Result: Reconfiguration failed - other unacceptable parameters (0x0004) Fix L2CAP/ECFC/BI-07-C when MPS reduced for more than one channel: > ACL Data RX: Handle 64 flags 0x02 dlen 16 LE L2CAP: Enhanced Credit Reconfigure Request (0x19) ident 3 len 8 MTU: 84 ! MPS: 71 Source CID: 64 ! Source CID: 65 < ACL Data TX: Handle 64 flags 0x00 dlen 10 LE L2CAP: Enhanced Credit Reconfigure Respond (0x1a) ident 2 len 2 ! Result: Reconfiguration successful (0x0000) Result: Reconfiguration failed - reduction in size of MPS not allowed for more than one channel at a time (0x0002) Link: https://github.com/bluez/bluez/issues/1865 Fixes: 15f02b910562 ("Bluetooth: L2CAP: Add initial code for Enhanced Credit Based Mode") Signed-off-by: Luiz Augusto von Dentz Signed-off-by: Sasha Levin

Bluetooth: hci_conn: use mod_delayed_work for active mode timeout

2026-03-04T12:20:02Z

[ Upstream commit 49d0901e260739de2fcc90c0c29f9e31e39a2d9b ] hci_conn_enter_active_mode() uses queue_delayed_work() with the intention that the work will run after the given timeout. However, queue_delayed_work() does nothing if the work is already queued, so depending on the link policy we may end up putting the connection into idle mode every hdev->idle_timeout ms. Use mod_delayed_work() instead so the work is queued if not already queued, and the timeout is updated otherwise. Signed-off-by: Stefan Sørensen Signed-off-by: Luiz Augusto von Dentz Signed-off-by: Sasha Levin

Bluetooth: Add more enc key size check

2025-12-06T21:08:24Z

[ Upstream commit 04a342cc49a8522e99c9b3346371c329d841dcd2 ] When we are slave role and receives l2cap conn req when encryption has started, we should check the enc key size to avoid KNOB attack or BLUFFS attack. >From SIG recommendation, implementations are advised to reject service-level connections on an encrypted baseband link with key strengths below 7 octets. A simple and clear way to achieve this is to place the enc key size check in hci_cc_read_enc_key_size() The btmon log below shows the case that lacks enc key size check. > HCI Event: Connect Request (0x04) plen 10 Address: BB:22:33:44:55:99 (OUI BB-22-33) Class: 0x480104 Major class: Computer (desktop, notebook, PDA, organizers) Minor class: Desktop workstation Capturing (Scanner, Microphone) Telephony (Cordless telephony, Modem, Headset) Link type: ACL (0x01) < HCI Command: Accept Connection Request (0x01|0x0009) plen 7 Address: BB:22:33:44:55:99 (OUI BB-22-33) Role: Peripheral (0x01) > HCI Event: Command Status (0x0f) plen 4 Accept Connection Request (0x01|0x0009) ncmd 2 Status: Success (0x00) > HCI Event: Connect Complete (0x03) plen 11 Status: Success (0x00) Handle: 1 Address: BB:22:33:44:55:99 (OUI BB-22-33) Link type: ACL (0x01) Encryption: Disabled (0x00) ... > HCI Event: Encryption Change (0x08) plen 4 Status: Success (0x00) Handle: 1 Address: BB:22:33:44:55:99 (OUI BB-22-33) Encryption: Enabled with E0 (0x01) < HCI Command: Read Encryption Key Size (0x05|0x0008) plen 2 Handle: 1 Address: BB:22:33:44:55:99 (OUI BB-22-33) > HCI Event: Command Complete (0x0e) plen 7 Read Encryption Key Size (0x05|0x0008) ncmd 2 Status: Success (0x00) Handle: 1 Address: BB:22:33:44:55:99 (OUI BB-22-33) Key size: 6 // We should check the enc key size ... > ACL Data RX: Handle 1 flags 0x02 dlen 12 L2CAP: Connection Request (0x02) ident 3 len 4 PSM: 25 (0x0019) Source CID: 64 < ACL Data TX: Handle 1 flags 0x00 dlen 16 L2CAP: Connection Response (0x03) ident 3 len 8 Destination CID: 64 Source CID: 64 Result: Connection pending (0x0001) Status: Authorization pending (0x0002) > HCI Event: Number of Completed Packets (0x13) plen 5 Num handles: 1 Handle: 1 Address: BB:22:33:44:55:99 (OUI BB-22-33) Count: 1 #35: len 16 (25 Kb/s) Latency: 5 msec (2-7 msec ~4 msec) < ACL Data TX: Handle 1 flags 0x00 dlen 16 L2CAP: Connection Response (0x03) ident 3 len 8 Destination CID: 64 Source CID: 64 Result: Connection successful (0x0000) Status: No further information available (0x0000) Cc: stable@vger.kernel.org Signed-off-by: Alex Lu Signed-off-by: Max Chou Signed-off-by: Luiz Augusto von Dentz [ Nazar Kalashnikov: change status to rp_status due to function parameter conflict ] Signed-off-by: Nazar Kalashnikov Signed-off-by: Greg Kroah-Hartman

Bluetooth: SMP: Fix not generating mackey and ltk when repairing

2025-12-06T21:08:22Z

[ Upstream commit 545d7827b2cd5de5eb85580cebeda6b35b3ff443 ] The change eed467b517e8 ("Bluetooth: fix passkey uninitialized when used") introduced a goto that bypasses the creation of temporary mackey and ltk which are later used by the likes of DHKey Check step. Later ffee202a78c2 ("Bluetooth: Always request for user confirmation for Just Works (LE SC)") which means confirm_hint is always set in case JUST_WORKS so the branch checking for an existing LTK becomes pointless as confirm_hint will always be set, so this just merge both cases of malicious or legitimate devices to be confirmed before continuing with the pairing procedure. Link: https://github.com/bluez/bluez/issues/1622 Fixes: eed467b517e8 ("Bluetooth: fix passkey uninitialized when used") Signed-off-by: Luiz Augusto von Dentz Signed-off-by: Sasha Levin

Bluetooth: L2CAP: export l2cap_chan_hold for modules

2025-12-06T21:08:18Z

[ Upstream commit e060088db0bdf7932e0e3c2d24b7371c4c5b867c ] l2cap_chan_put() is exported, so export also l2cap_chan_hold() for modules. l2cap_chan_hold() has use case in net/bluetooth/6lowpan.c Signed-off-by: Pauli Virtanen Reviewed-by: Paul Menzel Signed-off-by: Luiz Augusto von Dentz Signed-off-by: Sasha Levin