linux.git/include/net/bluetooth, branch v7.1-rc7 Linux kernel source tree Bluetooth: L2CAP: reject BR/EDR signaling packets over MTUsig 2026-06-03T15:21:24+00:00 Michael Bommarito michael.bommarito@gmail.com 2026-05-21T14:45:17+00:00 dd214733544427587a95f66dbf3adff072568990 net/bluetooth/l2cap_core.c:l2cap_sig_channel() accepts BR/EDR signaling packets up to the channel MTU and dispatches each command without enforcing the signaling MTU (MTUsig). A Bluetooth BR/EDR peer within radio range can send a fixed-channel CID 0x0001 packet that is larger than MTUsig and contains many L2CAP_ECHO_REQ commands before pairing. In a real-radio stock-kernel run, one 681-byte signaling packet containing 168 zero-length ECHO_REQ commands made the target transmit 168 ECHO_RSP frames over about 220 ms. Impact: a Bluetooth BR/EDR peer within radio range, before pairing, can force 168 ECHO_RSP frames from one 681-byte fixed-channel signaling packet containing packed ECHO_REQ commands. Define Linux's BR/EDR signaling MTU as the spec minimum of 48 bytes and reject any larger signaling packet with one L2CAP_COMMAND_REJECT_RSP carrying L2CAP_REJ_MTU_EXCEEDED before any command is dispatched. The Bluetooth Core spec wording for MTUExceeded says the reject identifier shall match the first request command in the packet, and that packets containing only responses shall be silently discarded. Linux intentionally deviates from that prescription: silently discarding desynchronizes the peer because the remote stack never learns its responses were dropped, and locating the first request command requires walking command headers past MTUsig, i.e. processing bytes from a packet we have already decided is too large to process. We therefore always emit one reject and use the identifier from the first command header, a single fixed-offset byte read. The unrestricted BR/EDR signaling parser and ECHO_REQ response path both trace to the initial git import; no later introducing commit is available for a Fixes tag. Cc: stable@vger.kernel.org Suggested-by: Luiz Augusto von Dentz <luiz.dentz@gmail.com> Link: https://lore.kernel.org/r/20260518002800.1361430-1-michael.bommarito@gmail.com Link: https://lore.kernel.org/r/20260520135034.1060859-1-michael.bommarito@gmail.com Link: https://lore.kernel.org/r/20260521000555.3712030-1-michael.bommarito@gmail.com Assisted-by: Claude:claude-opus-4-7 Assisted-by: Codex:gpt-5-5-xhigh Signed-off-by: Michael Bommarito <michael.bommarito@gmail.com> Signed-off-by: Luiz Augusto von Dentz <luiz.von.dentz@intel.com> 
net/bluetooth/l2cap_core.c:l2cap_sig_channel() accepts BR/EDR
signaling packets up to the channel MTU and dispatches each command
without enforcing the signaling MTU (MTUsig). A Bluetooth BR/EDR peer
within radio range can send a fixed-channel CID 0x0001 packet that is
larger than MTUsig and contains many L2CAP_ECHO_REQ commands before
pairing. In a real-radio stock-kernel run, one 681-byte signaling
packet containing 168 zero-length ECHO_REQ commands made the target
transmit 168 ECHO_RSP frames over about 220 ms.

Impact: a Bluetooth BR/EDR peer within radio range, before pairing, can
force 168 ECHO_RSP frames from one 681-byte fixed-channel signaling
packet containing packed ECHO_REQ commands.

Define Linux's BR/EDR signaling MTU as the spec minimum of 48 bytes and
reject any larger signaling packet with one L2CAP_COMMAND_REJECT_RSP
carrying L2CAP_REJ_MTU_EXCEEDED before any command is dispatched.

The Bluetooth Core spec wording for MTUExceeded says the reject
identifier shall match the first request command in the packet, and
that packets containing only responses shall be silently discarded.
Linux intentionally deviates from that prescription: silently
discarding desynchronizes the peer because the remote stack never
learns its responses were dropped, and locating the first request
command requires walking command headers past MTUsig, i.e. processing
bytes from a packet we have already decided is too large to process.
We therefore always emit one reject and use the identifier from the
first command header, a single fixed-offset byte read.

The unrestricted BR/EDR signaling parser and ECHO_REQ response path both
trace to the initial git import; no later introducing commit is
available for a Fixes tag.

Cc: stable@vger.kernel.org
Suggested-by: Luiz Augusto von Dentz <luiz.dentz@gmail.com>
Link: https://lore.kernel.org/r/20260518002800.1361430-1-michael.bommarito@gmail.com
Link: https://lore.kernel.org/r/20260520135034.1060859-1-michael.bommarito@gmail.com
Link: https://lore.kernel.org/r/20260521000555.3712030-1-michael.bommarito@gmail.com
Assisted-by: Claude:claude-opus-4-7
Assisted-by: Codex:gpt-5-5-xhigh
Signed-off-by: Michael Bommarito <michael.bommarito@gmail.com>
Signed-off-by: Luiz Augusto von Dentz <luiz.von.dentz@intel.com>
Bluetooth: serialize accept_q access 2026-05-14T13:49:56+00:00 Jiexun Wang wangjiexun2025@gmail.com 2026-05-06T11:43:30+00:00 e83f5e24da741fa9405aeeff00b08c5ee7c37b88 bt_sock_poll() walks the accept queue without synchronization, while child teardown can unlink the same socket and drop its last reference. The unsynchronized accept queue walk has existed since the initial Bluetooth import. Protect accept_q with a dedicated lock for queue updates and polling. Also rework bt_accept_dequeue() to take temporary child references under the queue lock before dropping it and locking the child socket. Fixes: 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 ("Linux-2.6.12-rc2") Cc: stable@vger.kernel.org Reported-by: Jann Horn <jannh@google.com> Reported-by: Yuan Tan <yuantan098@gmail.com> Reported-by: Yifan Wu <yifanwucs@gmail.com> Reported-by: Juefei Pu <tomapufckgml@gmail.com> Reported-by: Xin Liu <bird@lzu.edu.cn> Signed-off-by: Jiexun Wang <wangjiexun2025@gmail.com> Signed-off-by: Ren Wei <n05ec@lzu.edu.cn> Signed-off-by: Jiexun Wang <wangjiexun2025@gmail.com> Reviewed-by: Jann Horn <jannh@google.com> Signed-off-by: Luiz Augusto von Dentz <luiz.von.dentz@intel.com> 
bt_sock_poll() walks the accept queue without synchronization, while
child teardown can unlink the same socket and drop its last reference.
The unsynchronized accept queue walk has existed since the initial
Bluetooth import.

Protect accept_q with a dedicated lock for queue updates and polling.
Also rework bt_accept_dequeue() to take temporary child references under
the queue lock before dropping it and locking the child socket.

Fixes: 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 ("Linux-2.6.12-rc2")
Cc: stable@vger.kernel.org
Reported-by: Jann Horn <jannh@google.com>
Reported-by: Yuan Tan <yuantan098@gmail.com>
Reported-by: Yifan Wu <yifanwucs@gmail.com>
Reported-by: Juefei Pu <tomapufckgml@gmail.com>
Reported-by: Xin Liu <bird@lzu.edu.cn>
Signed-off-by: Jiexun Wang <wangjiexun2025@gmail.com>
Signed-off-by: Ren Wei <n05ec@lzu.edu.cn>
Signed-off-by: Jiexun Wang <wangjiexun2025@gmail.com>
Reviewed-by: Jann Horn <jannh@google.com>
Signed-off-by: Luiz Augusto von Dentz <luiz.von.dentz@intel.com>
Bluetooth: l2cap: defer conn param update to avoid conn->lock/hdev->lock inversion 2026-05-06T20:20:51+00:00 Mikhail Gavrilov mikhail.v.gavrilov@gmail.com 2026-04-14T21:52:37+00:00 91b5a598b5285da794b72619f31777b62dd336f8 When a BLE peripheral sends an L2CAP Connection Parameter Update Request the processing path is: process_pending_rx() [takes conn->lock] l2cap_le_sig_channel() l2cap_conn_param_update_req() hci_le_conn_update() [takes hdev->lock] Meanwhile other code paths take the locks in the opposite order: l2cap_chan_connect() [takes hdev->lock] ... mutex_lock(&conn->lock) l2cap_conn_ready() [hdev->lock via hci_cb_list_lock] ... mutex_lock(&conn->lock) This is a classic AB/BA deadlock which lockdep reports as a circular locking dependency when connecting a BLE MIDI keyboard (Carry-On FC-49). Fix this by making hci_le_conn_update() defer the HCI command through hci_cmd_sync_queue() so it no longer needs to take hdev->lock in the caller context. The sync callback uses __hci_cmd_sync_status_sk() to wait for the HCI_EV_LE_CONN_UPDATE_COMPLETE event, then updates the stored connection parameters (hci_conn_params) and notifies userspace (mgmt_new_conn_param) only after the controller has confirmed the update. A reference on hci_conn is held via hci_conn_get()/hci_conn_put() for the lifetime of the queued work to prevent use-after-free, and hci_conn_valid() is checked before proceeding in case the connection was removed while the work was pending. The hci_dev_lock is held across hci_conn_valid() and all conn field accesses to prevent a concurrent disconnect from invalidating the connection mid-use. Fixes: f044eb0524a0 ("Bluetooth: Store latency and supervision timeout in connection params") Signed-off-by: Mikhail Gavrilov <mikhail.v.gavrilov@gmail.com> Reviewed-by: Paul Menzel <pmenzel@molgen.mpg.de> Signed-off-by: Luiz Augusto von Dentz <luiz.von.dentz@intel.com> 
When a BLE peripheral sends an L2CAP Connection Parameter Update Request
the processing path is:

  process_pending_rx()          [takes conn->lock]
    l2cap_le_sig_channel()
      l2cap_conn_param_update_req()
        hci_le_conn_update()    [takes hdev->lock]

Meanwhile other code paths take the locks in the opposite order:

  l2cap_chan_connect()          [takes hdev->lock]
    ...
      mutex_lock(&conn->lock)

  l2cap_conn_ready()            [hdev->lock via hci_cb_list_lock]
    ...
      mutex_lock(&conn->lock)

This is a classic AB/BA deadlock which lockdep reports as a circular
locking dependency when connecting a BLE MIDI keyboard (Carry-On FC-49).

Fix this by making hci_le_conn_update() defer the HCI command through
hci_cmd_sync_queue() so it no longer needs to take hdev->lock in the
caller context.  The sync callback uses __hci_cmd_sync_status_sk() to
wait for the HCI_EV_LE_CONN_UPDATE_COMPLETE event, then updates the
stored connection parameters (hci_conn_params) and notifies userspace
(mgmt_new_conn_param) only after the controller has confirmed the update.

A reference on hci_conn is held via hci_conn_get()/hci_conn_put() for
the lifetime of the queued work to prevent use-after-free, and
hci_conn_valid() is checked before proceeding in case the connection was
removed while the work was pending.  The hci_dev_lock is held across
hci_conn_valid() and all conn field accesses to prevent a concurrent
disconnect from invalidating the connection mid-use.

Fixes: f044eb0524a0 ("Bluetooth: Store latency and supervision timeout in connection params")
Signed-off-by: Mikhail Gavrilov <mikhail.v.gavrilov@gmail.com>
Reviewed-by: Paul Menzel <pmenzel@molgen.mpg.de>
Signed-off-by: Luiz Augusto von Dentz <luiz.von.dentz@intel.com>
Bluetooth: hci.h: Avoid a couple -Wflex-array-member-not-at-end warnings 2026-04-13T13:19:42+00:00 Gustavo A. R. Silva gustavoars@kernel.org 2026-04-07T20:16:46+00:00 a0cff16d0f6e0bcd4173583694b85df42912e644 -Wflex-array-member-not-at-end was introduced in GCC-14, and we are getting ready to enable it, globally. struct hci_std_codecs and struct hci_std_codecs_v2 are flexible structures, this is structures that contain a flexible-array member (__u8 codec[]; and struct hci_std_codec_v2 codec[];, correspondingly.) Since struct hci_rp_read_local_supported_codecs and struct hci_rp_read_local_supported_codecs_v2 are defined by hardware, we create the new struct hci_std_codecs_hdr and struct hci_std_codecs_v2_hdr types, and use them to replace the object types causing trouble in struct hci_rp_read_local_supported_codecs and struct hci_rp_read_local_supported_codecs_v2, namely struct hci_std_codecs std_codecs; and struct hci_std_codecs_v2_hdr std_codecs;. Also, once -fms-extensions is enabled, we can use transparent struct members in both struct hci_std_codecs and struct hci_std_codecs_v2_hdr. Notice that the newly created types does not contain the flex-array member `codec`, which is the object causing the -Wfamnae warnings. After these changes, the size of struct hci_rp_read_local_supported_codecs and struct hci_rp_read_local_supported_codecs_v2, along with their member's offsets remain the same, hence the memory layouts don't change: Before changes: struct hci_rp_read_local_supported_codecs { __u8 status; /* 0 1 */ struct hci_std_codecs std_codecs; /* 1 1 */ struct hci_vnd_codecs vnd_codecs; /* 2 1 */ /* size: 3, cachelines: 1, members: 3 */ /* last cacheline: 3 bytes */ } __attribute__((__packed__)); struct hci_rp_read_local_supported_codecs_v2 { __u8 status; /* 0 1 */ struct hci_std_codecs_v2 std_codecs; /* 1 1 */ struct hci_vnd_codecs_v2 vendor_codecs; /* 2 1 */ /* size: 3, cachelines: 1, members: 3 */ /* last cacheline: 3 bytes */ } __attribute__((__packed__)); After changes: struct hci_rp_read_local_supported_codecs { __u8 status; /* 0 1 */ struct hci_std_codecs_hdr std_codecs; /* 1 1 */ struct hci_vnd_codecs vnd_codecs; /* 2 1 */ /* size: 3, cachelines: 1, members: 3 */ /* last cacheline: 3 bytes */ } __attribute__((__packed__)); struct hci_rp_read_local_supported_codecs_v2 { __u8 status; /* 0 1 */ struct hci_std_codecs_v2_hdr std_codecs; /* 1 1 */ struct hci_vnd_codecs_v2 vendor_codecs; /* 2 1 */ /* size: 3, cachelines: 1, members: 3 */ /* last cacheline: 3 bytes */ } __attribute__((__packed__)); With these changes fix the following warnings: include/net/bluetooth/hci.h:1490:31: warning: structure containing a flexible array member is not at the end of another structure [-Wflex-array-member-not-at-end] include/net/bluetooth/hci.h:1525:34: warning: structure containing a flexible array member is not at the end of another structure [-Wflex-array-member-not-at-end] Signed-off-by: Gustavo A. R. Silva <gustavoars@kernel.org> Signed-off-by: Luiz Augusto von Dentz <luiz.von.dentz@intel.com> 
-Wflex-array-member-not-at-end was introduced in GCC-14, and we are
getting ready to enable it, globally.

struct hci_std_codecs and struct hci_std_codecs_v2 are flexible
structures, this is structures that contain a flexible-array member
(__u8 codec[]; and struct hci_std_codec_v2 codec[];, correspondingly.)

Since struct hci_rp_read_local_supported_codecs and struct
hci_rp_read_local_supported_codecs_v2 are defined by hardware, we
create the new struct hci_std_codecs_hdr and struct hci_std_codecs_v2_hdr
types, and use them to replace the object types causing trouble in
struct hci_rp_read_local_supported_codecs and struct
hci_rp_read_local_supported_codecs_v2, namely struct hci_std_codecs
std_codecs; and struct hci_std_codecs_v2_hdr std_codecs;.

Also, once -fms-extensions is enabled, we can use transparent struct
members in both struct hci_std_codecs and struct hci_std_codecs_v2_hdr.

Notice that the newly created types does not contain the flex-array
member `codec`, which is the object causing the -Wfamnae warnings.

After these changes, the size of struct hci_rp_read_local_supported_codecs
and struct hci_rp_read_local_supported_codecs_v2, along with their
member's offsets remain the same, hence the memory layouts don't
change:

Before changes:
struct hci_rp_read_local_supported_codecs {
        __u8                       status;               /*     0     1 */
        struct hci_std_codecs      std_codecs;           /*     1     1 */
        struct hci_vnd_codecs      vnd_codecs;           /*     2     1 */

        /* size: 3, cachelines: 1, members: 3 */
        /* last cacheline: 3 bytes */
} __attribute__((__packed__));

struct hci_rp_read_local_supported_codecs_v2 {
        __u8                       status;               /*     0     1 */
        struct hci_std_codecs_v2   std_codecs;           /*     1     1 */
        struct hci_vnd_codecs_v2   vendor_codecs;        /*     2     1 */

        /* size: 3, cachelines: 1, members: 3 */
        /* last cacheline: 3 bytes */
} __attribute__((__packed__));

After changes:
struct hci_rp_read_local_supported_codecs {
	__u8                       status;               /*     0     1 */
	struct hci_std_codecs_hdr  std_codecs;           /*     1     1 */
	struct hci_vnd_codecs      vnd_codecs;           /*     2     1 */

	/* size: 3, cachelines: 1, members: 3 */
	/* last cacheline: 3 bytes */
} __attribute__((__packed__));

struct hci_rp_read_local_supported_codecs_v2 {
	__u8                       status;               /*     0     1 */
	struct hci_std_codecs_v2_hdr std_codecs;         /*     1     1 */
	struct hci_vnd_codecs_v2   vendor_codecs;        /*     2     1 */

	/* size: 3, cachelines: 1, members: 3 */
	/* last cacheline: 3 bytes */
} __attribute__((__packed__));

With these changes fix the following warnings:

include/net/bluetooth/hci.h:1490:31: warning: structure containing a flexible array member is not at the end of another structure [-Wflex-array-member-not-at-end]
include/net/bluetooth/hci.h:1525:34: warning: structure containing a flexible array member is not at the end of another structure [-Wflex-array-member-not-at-end]

Signed-off-by: Gustavo A. R. Silva <gustavoars@kernel.org>
Signed-off-by: Luiz Augusto von Dentz <luiz.von.dentz@intel.com>
Bluetooth: L2CAP: Fix regressions caused by reusing ident 2026-03-19T18:44:25+00:00 Luiz Augusto von Dentz luiz.von.dentz@intel.com 2026-03-17T15:54:01+00:00 761fb8ec8778f0caf2bba5a41e3cff1ea86974f3 This attempt to fix regressions caused by reusing ident which apparently is not handled well on certain stacks causing the stack to not respond to requests, so instead of simple returning the first unallocated id this stores the last used tx_ident and then attempt to use the next until all available ids are exausted and then cycle starting over to 1. Link: https://bugzilla.kernel.org/show_bug.cgi?id=221120 Link: https://bugzilla.kernel.org/show_bug.cgi?id=221177 Fixes: 6c3ea155e5ee ("Bluetooth: L2CAP: Fix not tracking outstanding TX ident") Signed-off-by: Luiz Augusto von Dentz <luiz.von.dentz@intel.com> Tested-by: Christian Eggers <ceggers@arri.de> 
This attempt to fix regressions caused by reusing ident which apparently
is not handled well on certain stacks causing the stack to not respond to
requests, so instead of simple returning the first unallocated id this
stores the last used tx_ident and then attempt to use the next until all
available ids are exausted and then cycle starting over to 1.

Link: https://bugzilla.kernel.org/show_bug.cgi?id=221120
Link: https://bugzilla.kernel.org/show_bug.cgi?id=221177
Fixes: 6c3ea155e5ee ("Bluetooth: L2CAP: Fix not tracking outstanding TX ident")
Signed-off-by: Luiz Augusto von Dentz <luiz.von.dentz@intel.com>
Tested-by: Christian Eggers <ceggers@arri.de>
Bluetooth: L2CAP: Fix result of L2CAP_ECRED_CONN_RSP when MTU is too short 2026-02-23T20:28:56+00:00 Luiz Augusto von Dentz luiz.von.dentz@intel.com 2026-02-05T20:11:34+00:00 c28d2bff70444a85b3b86aaf241ece9408c7858c Test L2CAP/ECFC/BV-26-C expect the response to L2CAP_ECRED_CONN_REQ with and MTU value < L2CAP_ECRED_MIN_MTU (64) to be L2CAP_CR_LE_INVALID_PARAMS rather than L2CAP_CR_LE_UNACCEPT_PARAMS. Also fix not including the correct number of CIDs in the response since the spec requires all CIDs being rejected to be included in the response. Link: https://github.com/bluez/bluez/issues/1868 Fixes: 15f02b910562 ("Bluetooth: L2CAP: Add initial code for Enhanced Credit Based Mode") Signed-off-by: Luiz Augusto von Dentz <luiz.von.dentz@intel.com> 
Test L2CAP/ECFC/BV-26-C expect the response to L2CAP_ECRED_CONN_REQ with
and MTU value < L2CAP_ECRED_MIN_MTU (64) to be L2CAP_CR_LE_INVALID_PARAMS
rather than L2CAP_CR_LE_UNACCEPT_PARAMS.

Also fix not including the correct number of CIDs in the response since
the spec requires all CIDs being rejected to be included in the
response.

Link: https://github.com/bluez/bluez/issues/1868
Fixes: 15f02b910562 ("Bluetooth: L2CAP: Add initial code for Enhanced Credit Based Mode")
Signed-off-by: Luiz Augusto von Dentz <luiz.von.dentz@intel.com>
Bluetooth: L2CAP: Fix invalid response to L2CAP_ECRED_RECONF_REQ 2026-02-23T20:23:37+00:00 Luiz Augusto von Dentz luiz.von.dentz@intel.com 2026-02-03T20:16:16+00:00 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 <luiz.von.dentz@intel.com> 
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 <luiz.von.dentz@intel.com>
Bluetooth: L2CAP: Fix not tracking outstanding TX ident 2026-01-29T18:36:35+00:00 Luiz Augusto von Dentz luiz.von.dentz@intel.com 2026-01-21T21:39:44+00:00 6c3ea155e5ee3e56606233acde8309afda66d483 This attempts to proper track outstanding request by using struct ida and allocating from it in l2cap_get_ident using ida_alloc_range which would reuse ids as they are free, then upon completion release the id using ida_free. This fixes the qualification test case L2CAP/COS/CED/BI-29-C which attempts to check if the host stack is able to work after 256 attempts to connect which requires Ident field to use the full range of possible values in order to pass the test. Link: https://github.com/bluez/bluez/issues/1829 Signed-off-by: Luiz Augusto von Dentz <luiz.von.dentz@intel.com> Reviewed-by: Paul Menzel <pmenzel@molgen.mpg.de> 
This attempts to proper track outstanding request by using struct ida
and allocating from it in l2cap_get_ident using ida_alloc_range which
would reuse ids as they are free, then upon completion release
the id using ida_free.

This fixes the qualification test case L2CAP/COS/CED/BI-29-C which
attempts to check if the host stack is able to work after 256 attempts
to connect which requires Ident field to use the full range of possible
values in order to pass the test.

Link: https://github.com/bluez/bluez/issues/1829
Signed-off-by: Luiz Augusto von Dentz <luiz.von.dentz@intel.com>
Reviewed-by: Paul Menzel <pmenzel@molgen.mpg.de>
Bluetooth: Fix using PHYs bitfields as PHY value 2026-01-29T18:27:47+00:00 Luiz Augusto von Dentz luiz.von.dentz@intel.com 2025-12-22T19:36:45+00:00 0e2a6af81042e048bef1fddc70a022272d11ae84 This renames the PHY fields in bt_iso_io_qos to PHYs (plural) since it represents a bitfield where multiple PHYs can be set and make the same change also to HCI_OP_LE_SET_CIG_PARAMS since both c_phy and p_phy fields are bitfields. This also fixes the assumption that hci_evt_le_cis_established PHYs fields are compatible with bt_iso_io_qos, they are not, the fields in hci_evt_le_cis_established represent just a single PHY value so they need to be converted to bitfield when set in bt_iso_io_qos. Signed-off-by: Luiz Augusto von Dentz <luiz.von.dentz@intel.com> 
This renames the PHY fields in bt_iso_io_qos to PHYs (plural) since it
represents a bitfield where multiple PHYs can be set and make the same
change also to HCI_OP_LE_SET_CIG_PARAMS since both c_phy and p_phy
fields are bitfields.

This also fixes the assumption that hci_evt_le_cis_established PHYs
fields are compatible with bt_iso_io_qos, they are not, the fields in
hci_evt_le_cis_established represent just a single PHY value so they
need to be converted to bitfield when set in bt_iso_io_qos.

Signed-off-by: Luiz Augusto von Dentz <luiz.von.dentz@intel.com>
Bluetooth: L2CAP: Add support for setting BT_PHY 2026-01-29T18:25:34+00:00 Luiz Augusto von Dentz luiz.von.dentz@intel.com 2025-12-17T15:50:51+00:00 132c0779d4a2d08541519cf04783bca52c6ec85c This enables client to use setsockopt(BT_PHY) to set the connection packet type/PHY: Example setting BT_PHY_BR_1M_1SLOT: < HCI Command: Change Conne.. (0x01|0x000f) plen 4 Handle: 1 Address: 00:AA:01:01:00:00 (Intel Corporation) Packet type: 0x331e 2-DH1 may not be used 3-DH1 may not be used DM1 may be used DH1 may be used 2-DH3 may not be used 3-DH3 may not be used 2-DH5 may not be used 3-DH5 may not be used > HCI Event: Command Status (0x0f) plen 4 Change Connection Packet Type (0x01|0x000f) ncmd 1 Status: Success (0x00) > HCI Event: Connection Packet Typ.. (0x1d) plen 5 Status: Success (0x00) Handle: 1 Address: 00:AA:01:01:00:00 (Intel Corporation) Packet type: 0x331e 2-DH1 may not be used 3-DH1 may not be used DM1 may be used DH1 may be used 2-DH3 may not be used 3-DH3 may not be used 2-DH5 may not be used Example setting BT_PHY_LE_1M_TX and BT_PHY_LE_1M_RX: < HCI Command: LE Set PHY (0x08|0x0032) plen 7 Handle: 1 Address: 00:AA:01:01:00:00 (Intel Corporation) All PHYs preference: 0x00 TX PHYs preference: 0x01 LE 1M RX PHYs preference: 0x01 LE 1M PHY options preference: Reserved (0x0000) > HCI Event: Command Status (0x0f) plen 4 LE Set PHY (0x08|0x0032) ncmd 1 Status: Success (0x00) > HCI Event: LE Meta Event (0x3e) plen 6 LE PHY Update Complete (0x0c) Status: Success (0x00) Handle: 1 Address: 00:AA:01:01:00:00 (Intel Corporation) TX PHY: LE 1M (0x01) RX PHY: LE 1M (0x01) Signed-off-by: Luiz Augusto von Dentz <luiz.von.dentz@intel.com> 
This enables client to use setsockopt(BT_PHY) to set the connection
packet type/PHY:

Example setting BT_PHY_BR_1M_1SLOT:

< HCI Command: Change Conne.. (0x01|0x000f) plen 4
        Handle: 1 Address: 00:AA:01:01:00:00 (Intel Corporation)
        Packet type: 0x331e
          2-DH1 may not be used
          3-DH1 may not be used
          DM1 may be used
          DH1 may be used
          2-DH3 may not be used
          3-DH3 may not be used
          2-DH5 may not be used
          3-DH5 may not be used
> HCI Event: Command Status (0x0f) plen 4
      Change Connection Packet Type (0x01|0x000f) ncmd 1
        Status: Success (0x00)
> HCI Event: Connection Packet Typ.. (0x1d) plen 5
        Status: Success (0x00)
        Handle: 1 Address: 00:AA:01:01:00:00 (Intel Corporation)
        Packet type: 0x331e
          2-DH1 may not be used
          3-DH1 may not be used
          DM1 may be used
          DH1 may be used
          2-DH3 may not be used
          3-DH3 may not be used
          2-DH5 may not be used

Example setting BT_PHY_LE_1M_TX and BT_PHY_LE_1M_RX:

< HCI Command: LE Set PHY (0x08|0x0032) plen 7
        Handle: 1 Address: 00:AA:01:01:00:00 (Intel Corporation)
        All PHYs preference: 0x00
        TX PHYs preference: 0x01
          LE 1M
        RX PHYs preference: 0x01
          LE 1M
        PHY options preference: Reserved (0x0000)
> HCI Event: Command Status (0x0f) plen 4
      LE Set PHY (0x08|0x0032) ncmd 1
        Status: Success (0x00)
> HCI Event: LE Meta Event (0x3e) plen 6
      LE PHY Update Complete (0x0c)
        Status: Success (0x00)
        Handle: 1 Address: 00:AA:01:01:00:00 (Intel Corporation)
        TX PHY: LE 1M (0x01)
        RX PHY: LE 1M (0x01)

Signed-off-by: Luiz Augusto von Dentz <luiz.von.dentz@intel.com>