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Bluetooth: L2CAP: Try harder to accept device not knowing options

PATCH In review Bastien Nocera 5 participants 14 messages Dec 8, 2020 – Jan 26, 2021 1 message not in the archive

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Bastien Nocera

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#0 lore raw

PATCH 1/1 Bluetooth: L2CAP: Try harder to accept device not knowing options

The current implementation of L2CAP options negotiation will continue the negotiation when a device responds with L2CAP_CONF_UNACCEPT ("unaccepted options"), but not when the device replies with L2CAP_CONF_UNKNOWN ("unknown options").

Trying to continue the negotiation without ERTM support will allow Bluetooth-capable XBox One controllers (notably models 1708 and 1797) to connect.

btmon before patch:

Quoted 1 line

ACL Data RX: Handle 256 flags 0x02 dlen 16 #64 [hci0] 59.182702

      L2CAP: Connection Response (0x03) ident 2 len 8
        Destination CID: 64
        Source CID: 64
        Result: Connection successful (0x0000)
        Status: No further information available (0x0000)

< ACL Data TX: Handle 256 flags 0x00 dlen 23 #65 [hci0] 59.182744
L2CAP: Configure Request (0x04) ident 3 len 15
Destination CID: 64
Flags: 0x0000
Option: Retransmission and Flow Control (0x04) [mandatory]
Mode: Basic (0x00)
TX window size: 0
Max transmit: 0
Retransmission timeout: 0
Monitor timeout: 0
Maximum PDU size: 0

Quoted 1 line

ACL Data RX: Handle 256 flags 0x02 dlen 16 #66 [hci0] 59.183948

      L2CAP: Configure Request (0x04) ident 1 len 8
        Destination CID: 64
        Flags: 0x0000
        Option: Maximum Transmission Unit (0x01) [mandatory]
          MTU: 1480
< ACL Data TX: Handle 256 flags 0x00 dlen 18                            #67 [hci0] 59.183994
      L2CAP: Configure Response (0x05) ident 1 len 10
        Source CID: 64
        Flags: 0x0000
        Result: Success (0x0000)
        Option: Maximum Transmission Unit (0x01) [mandatory]
          MTU: 1480
Quoted 1 line

ACL Data RX: Handle 256 flags 0x02 dlen 15 #69 [hci0] 59.187676

      L2CAP: Configure Response (0x05) ident 3 len 7
        Source CID: 64
        Flags: 0x0000
        Result: Failure - unknown options (0x0003)
        04                                               .

< ACL Data TX: Handle 256 flags 0x00 dlen 12 #70 [hci0] 59.187722
L2CAP: Disconnection Request (0x06) ident 4 len 4
Destination CID: 64
Source CID: 64

Quoted 1 line

ACL Data RX: Handle 256 flags 0x02 dlen 12 #73 [hci0] 59.192714

L2CAP: Disconnection Response (0x07) ident 4 len 4
Destination CID: 64
Source CID: 64

btmon after patch:

Quoted 1 line

ACL Data RX: Handle 256 flags 0x02 dlen 16 #248 [hci0] 103.502970

      L2CAP: Connection Response (0x03) ident 5 len 8
        Destination CID: 65
        Source CID: 65
        Result: Connection pending (0x0001)
        Status: No further information available (0x0000)
Quoted 1 line

ACL Data RX: Handle 256 flags 0x02 dlen 16 #249 [hci0] 103.504184

      L2CAP: Connection Response (0x03) ident 5 len 8
        Destination CID: 65
        Source CID: 65
        Result: Connection successful (0x0000)
        Status: No further information available (0x0000)

< ACL Data TX: Handle 256 flags 0x00 dlen 23 #250 [hci0] 103.504398
L2CAP: Configure Request (0x04) ident 6 len 15
Destination CID: 65
Flags: 0x0000
Option: Retransmission and Flow Control (0x04) [mandatory]
Mode: Basic (0x00)
TX window size: 0
Max transmit: 0
Retransmission timeout: 0
Monitor timeout: 0
Maximum PDU size: 0

Quoted 1 line

ACL Data RX: Handle 256 flags 0x02 dlen 16 #251 [hci0] 103.505472

      L2CAP: Configure Request (0x04) ident 3 len 8
        Destination CID: 65
        Flags: 0x0000
        Option: Maximum Transmission Unit (0x01) [mandatory]
          MTU: 1480
< ACL Data TX: Handle 256 flags 0x00 dlen 18                          #252 [hci0] 103.505689
      L2CAP: Configure Response (0x05) ident 3 len 10
        Source CID: 65
        Flags: 0x0000
        Result: Success (0x0000)
        Option: Maximum Transmission Unit (0x01) [mandatory]
          MTU: 1480
Quoted 1 line

ACL Data RX: Handle 256 flags 0x02 dlen 15 #254 [hci0] 103.509165

      L2CAP: Configure Response (0x05) ident 6 len 7
        Source CID: 65
        Flags: 0x0000
        Result: Failure - unknown options (0x0003)
        04                                               .
< ACL Data TX: Handle 256 flags 0x00 dlen 12                          #255 [hci0] 103.509426
      L2CAP: Configure Request (0x04) ident 7 len 4
        Destination CID: 65
        Flags: 0x0000
< ACL Data TX: Handle 256 flags 0x00 dlen 12                          #257 [hci0] 103.511870
      L2CAP: Connection Request (0x02) ident 8 len 4
        PSM: 1 (0x0001)
        Source CID: 66
Quoted 1 line

ACL Data RX: Handle 256 flags 0x02 dlen 14 #259 [hci0] 103.514121

      L2CAP: Configure Response (0x05) ident 7 len 6
        Source CID: 65
        Flags: 0x0000
        Result: Success (0x0000)
Signed-off-by Florian Dollinger <[email protected]>
Co-developed-by Florian Dollinger <[email protected]>
---
 net/bluetooth/l2cap_core.c | 1 +
 1 file changed, 1 insertion(+)
net/bluetooth/l2cap_core.c +1 -0
index 1ab27b90ddcb..3ab95ea2cd80 100644
@@ -4513,6 +4513,7 @@ static inline int l2cap_config_rsp(struct l2cap_conn *conn,
 		}
 		goto done;
 
+	case L2CAP_CONF_UNKNOWN:
 	case L2CAP_CONF_UNACCEPT:
 		if (chan->num_conf_rsp <= L2CAP_CONF_MAX_CONF_RSP) {
 			char req[64];
Signature · 1 line
2.29.2
#1 lore raw

This is automated email and please do not reply to this email!

Dear submitter,

Thank you for submitting the patches to the linux bluetooth mailing list. This is a CI test results with your patch series:
PW Link:https://patchwork.kernel.org/project/bluetooth/list/?series=398401

---Test result---

##############################
Test: CheckPatch - FAIL
Output:
Bluetooth: L2CAP: Try harder to accept device not knowing options
WARNING: Possible unwrapped commit description (prefer a maximum 75 chars per line) #8:
the negotiation when a device responds with L2CAP_CONF_UNACCEPT ("unaccepted

WARNING: Co-developed-by: must be immediately followed by Signed-off-by:
#120:

Co-developed-by Florian Dollinger <[email protected]>

ERROR: Missing Signed-off-by: line by nominal patch author 'Bastien Nocera <[email protected]>'

total: 1 errors, 2 warnings, 0 checks, 7 lines checked

NOTE: For some of the reported defects, checkpatch may be able to
mechanically convert to the typical style using --fix or --fix-inplace.

"[PATCH] Bluetooth: L2CAP: Try harder to accept device not knowing" has style problems, please review.

NOTE: If any of the errors are false positives, please report
them to the maintainer, see CHECKPATCH in MAINTAINERS.

##############################
Test: CheckGitLint - FAIL
Output:
Bluetooth: L2CAP: Try harder to accept device not knowing options

13: B1 Line exceeds max length (92>80): "> ACL Data RX: Handle 256 flags 0x02 dlen 16                            #64 [hci0] 59.182702"
19: B1 Line exceeds max length (92>80): "< ACL Data TX: Handle 256 flags 0x00 dlen 23                            #65 [hci0] 59.182744"
30: B1 Line exceeds max length (92>80): "> ACL Data RX: Handle 256 flags 0x02 dlen 16                            #66 [hci0] 59.183948"
36: B1 Line exceeds max length (92>80): "< ACL Data TX: Handle 256 flags 0x00 dlen 18                            #67 [hci0] 59.183994"
43: B1 Line exceeds max length (92>80): "> ACL Data RX: Handle 256 flags 0x02 dlen 15                            #69 [hci0] 59.187676"
49: B1 Line exceeds max length (92>80): "< ACL Data TX: Handle 256 flags 0x00 dlen 12                            #70 [hci0] 59.187722"
53: B1 Line exceeds max length (92>80): "> ACL Data RX: Handle 256 flags 0x02 dlen 12                            #73 [hci0] 59.192714"
59: B1 Line exceeds max length (92>80): "> ACL Data RX: Handle 256 flags 0x02 dlen 16                          #248 [hci0] 103.502970"
65: B1 Line exceeds max length (92>80): "> ACL Data RX: Handle 256 flags 0x02 dlen 16                          #249 [hci0] 103.504184"
71: B1 Line exceeds max length (92>80): "< ACL Data TX: Handle 256 flags 0x00 dlen 23                          #250 [hci0] 103.504398"
82: B1 Line exceeds max length (92>80): "> ACL Data RX: Handle 256 flags 0x02 dlen 16                          #251 [hci0] 103.505472"
88: B1 Line exceeds max length (92>80): "< ACL Data TX: Handle 256 flags 0x00 dlen 18                          #252 [hci0] 103.505689"
95: B1 Line exceeds max length (92>80): "> ACL Data RX: Handle 256 flags 0x02 dlen 15                          #254 [hci0] 103.509165"
101: B1 Line exceeds max length (92>80): "< ACL Data TX: Handle 256 flags 0x00 dlen 12                          #255 [hci0] 103.509426"
105: B1 Line exceeds max length (92>80): "< ACL Data TX: Handle 256 flags 0x00 dlen 12                          #257 [hci0] 103.511870"
109: B1 Line exceeds max length (92>80): "> ACL Data RX: Handle 256 flags 0x02 dlen 14                          #259 [hci0] 103.514121"

##############################
Test: CheckBuildK - PASS

---
Regards,
Linux Bluetooth

A message that is not in the archive (sent off-list or not yet received): CABBYNZJNTDek+kKS5wtrr67Xx8DmFGvcV13cLSxULgJRa5N+3g@mail.gmail.com

author
#3 lore raw
Quoted 23 lines · Luiz Augusto von Dentz

Hi Bastien,

Quoted 9 lines · Bastien Nocera

The current implementation of L2CAP options negotiation will continue
the negotiation when a device responds with L2CAP_CONF_UNACCEPT ("unaccepted
options"), but not when the device replies with L2CAP_CONF_UNKNOWN ("unknown
options").

Quoted 4 lines

Trying to continue the negotiation without ERTM support will allow Bluetooth-capable XBox One controllers (notably models 1708 and 1797)
to connect.

While the bellow traces looks fine we need to confirm that it doesn't break the qualification tests e.g:

L2CAP/COS/CFD/BV-14-C [Unknown Mandatory Options Request]

Quoted 8 lines

• Test Purpose Verify that the IUT can give the appropriate error code
when the Lower Tester proposes any number of unknown options where at least one is mandatory.

Afaik it should be fine to continue with another round of configuration given that it only expects the error 0x0003, but we better confirm PTS doesn't expect a L2CAP Disconnect after it.

I have a Windows machine, and the PTS dongle. How do I set up the qualification test and run it against the Linux machine before and after the patch?

maintainer
#4 lore raw

Hi Tedd,

Quoted 30 lines · Bastien Nocera
Quoted 28 lines · Luiz Augusto von Dentz

Hi Bastien,

Quoted 9 lines · Bastien Nocera

The current implementation of L2CAP options negotiation will continue
the negotiation when a device responds with L2CAP_CONF_UNACCEPT ("unaccepted
options"), but not when the device replies with L2CAP_CONF_UNKNOWN ("unknown
options").

Quoted 4 lines

Trying to continue the negotiation without ERTM support will allow Bluetooth-capable XBox One controllers (notably models 1708 and 1797)
to connect.

While the bellow traces looks fine we need to confirm that it doesn't break the qualification tests e.g:

L2CAP/COS/CFD/BV-14-C [Unknown Mandatory Options Request]

• Test Purpose Verify that the IUT can give the appropriate error code
when the Lower Tester proposes any number of unknown options where at least one is mandatory.

Quoted 7 lines
Quoted 3 lines

Afaik it should be fine to continue with another round of configuration given that it only expects the error 0x0003, but we better confirm PTS doesn't expect a L2CAP Disconnect after it.

I have a Windows machine, and the PTS dongle. How do I set up the qualification test and run it against the Linux machine before and after the patch?

@Tedd: Do we happen to autopts working with BlueZ for L2CAP tests? Or perhaps anything that Bastien can use as a reference to test his changes.
@Batien: We would like to have autopts
(https://github.com/intel/auto-pts) to handle the qualification but there is still some work pending in order to enable it to work with L2CAP. Ultimately we could even attempt to integrate autopts on CI to run it automatically, but in order to do that we need:

1. We need to emulate the PTS dongle (USB emulator?)
2. Run a Windows VM on CI, attach the emulated dongle to it and run PTS on top (not sure if github actions do allow this)
3. Identify what tests need to run e.g. L2CAP changes should trigger only L2CAP tests

Signature · 1 line
Luiz Augusto von Dentz
author
#5 lore raw
In reply to a message not in the archive
Quoted 23 lines · Luiz Augusto von Dentz

Hi Bastien,

Quoted 9 lines · Bastien Nocera

The current implementation of L2CAP options negotiation will continue
the negotiation when a device responds with L2CAP_CONF_UNACCEPT ("unaccepted
options"), but not when the device replies with L2CAP_CONF_UNKNOWN ("unknown
options").

Quoted 4 lines

Trying to continue the negotiation without ERTM support will allow Bluetooth-capable XBox One controllers (notably models 1708 and 1797)
to connect.

While the bellow traces looks fine we need to confirm that it doesn't break the qualification tests e.g:

L2CAP/COS/CFD/BV-14-C [Unknown Mandatory Options Request]

Quoted 8 lines

• Test Purpose Verify that the IUT can give the appropriate error code
when the Lower Tester proposes any number of unknown options where at least one is mandatory.

Afaik it should be fine to continue with another round of configuration given that it only expects the error 0x0003, but we better confirm PTS doesn't expect a L2CAP Disconnect after it.

The tests fail for me in the same on a kernel with and without the patch:
- Expected that the IUT transmits an L2CAP_ConfigRsp includes the unsupported option that Lower Tester sent.
Final Verdict:FAIL
L2CAP/COS/CFD/BV-14-C finished

Is this expected? I was using an 5.10-rc7 kernel with and without the patch I sent. I can send you the full results off-list if you want them.

author
#6 lore raw
Quoted 9 lines · Bastien Nocera

<snip>
The tests fail for me in the same on a kernel with and without the
patch:
- Expected that the IUT transmits an L2CAP_ConfigRsp includes the unsupported option that Lower Tester sent.
Final Verdict:FAIL
L2CAP/COS/CFD/BV-14-C finished

Quoted 3 lines

Is this expected? I was using an 5.10-rc7 kernel with and without the patch I sent. I can send you the full results off-list if you want them.

Any news on that? Is the error expected, should I test with a newer version of the kernel? I'd really like to finally land this...

#7 lore raw

Hi Bastien,

For the test L2CAP/COS/CFD/BV-14-C, this patch is required to pass it.
https://git.kernel.org/pub/scm/linux/kernel/git/bluetooth/bluetooth-next.git/commit/?id=5b8ec15d02f12148ef0185825217162b3bc341f4

I don't think it is merged yet into 5.10, so you might need to apply the patch yourself.

Thanks,
Archie

Quoted 18 lines · Bastien Nocera
Quoted 9 lines · Bastien Nocera

<snip>
The tests fail for me in the same on a kernel with and without the
patch:
- Expected that the IUT transmits an L2CAP_ConfigRsp includes the unsupported option that Lower Tester sent.
Final Verdict:FAIL
L2CAP/COS/CFD/BV-14-C finished

Quoted 3 lines

Is this expected? I was using an 5.10-rc7 kernel with and without the patch I sent. I can send you the full results off-list if you want them.

Any news on that? Is the error expected, should I test with a newer version of the kernel? I'd really like to finally land this...

author
#9 lore raw
In reply to a message not in the archive
Quoted 23 lines · Luiz Augusto von Dentz

Hi Bastien,

Quoted 9 lines · Bastien Nocera

The current implementation of L2CAP options negotiation will continue
the negotiation when a device responds with L2CAP_CONF_UNACCEPT ("unaccepted
options"), but not when the device replies with L2CAP_CONF_UNKNOWN ("unknown
options").

Quoted 4 lines

Trying to continue the negotiation without ERTM support will allow Bluetooth-capable XBox One controllers (notably models 1708 and 1797)
to connect.

While the bellow traces looks fine we need to confirm that it doesn't break the qualification tests e.g:

L2CAP/COS/CFD/BV-14-C [Unknown Mandatory Options Request]

Quoted 8 lines

• Test Purpose Verify that the IUT can give the appropriate error code
when the Lower Tester proposes any number of unknown options where at least one is mandatory.

Afaik it should be fine to continue with another round of configuration given that it only expects the error 0x0003, but we better confirm PTS doesn't expect a L2CAP Disconnect after it.

I tested this today using Fedora's kernel-5.11.0-0.rc2.114.fc34:
https://koji.fedoraproject.org/koji/buildinfo?buildID=1664670
And a local build using the same source kernel with this patch on top.

Both managed to pass the test without any problems.

I'll send the results of the test privately to you and Marcel.

Cheers

maintainer Reviewed-by on v1 1/1
#10 lore raw
In reply to Bastien Nocera

Hi,

Quoted 107 lines · Bastien Nocera

The current implementation of L2CAP options negotiation will continue the negotiation when a device responds with L2CAP_CONF_UNACCEPT ("unaccepted options"), but not when the device replies with L2CAP_CONF_UNKNOWN ("unknown options").

Trying to continue the negotiation without ERTM support will allow Bluetooth-capable XBox One controllers (notably models 1708 and 1797) to connect.

btmon before patch:

Quoted 1 line

ACL Data RX: Handle 256 flags 0x02 dlen 16 #64 [hci0] 59.182702

      L2CAP: Connection Response (0x03) ident 2 len 8
        Destination CID: 64
        Source CID: 64
        Result: Connection successful (0x0000)
        Status: No further information available (0x0000)

< ACL Data TX: Handle 256 flags 0x00 dlen 23 #65 [hci0] 59.182744
L2CAP: Configure Request (0x04) ident 3 len 15
Destination CID: 64
Flags: 0x0000
Option: Retransmission and Flow Control (0x04) [mandatory]
Mode: Basic (0x00)
TX window size: 0
Max transmit: 0
Retransmission timeout: 0
Monitor timeout: 0
Maximum PDU size: 0

Quoted 1 line

ACL Data RX: Handle 256 flags 0x02 dlen 16 #66 [hci0] 59.183948

      L2CAP: Configure Request (0x04) ident 1 len 8
        Destination CID: 64
        Flags: 0x0000
        Option: Maximum Transmission Unit (0x01) [mandatory]
          MTU: 1480
< ACL Data TX: Handle 256 flags 0x00 dlen 18                            #67 [hci0] 59.183994
      L2CAP: Configure Response (0x05) ident 1 len 10
        Source CID: 64
        Flags: 0x0000
        Result: Success (0x0000)
        Option: Maximum Transmission Unit (0x01) [mandatory]
          MTU: 1480
Quoted 1 line

ACL Data RX: Handle 256 flags 0x02 dlen 15 #69 [hci0] 59.187676

      L2CAP: Configure Response (0x05) ident 3 len 7
        Source CID: 64
        Flags: 0x0000
        Result: Failure - unknown options (0x0003)
        04                                               .

< ACL Data TX: Handle 256 flags 0x00 dlen 12 #70 [hci0] 59.187722
L2CAP: Disconnection Request (0x06) ident 4 len 4
Destination CID: 64
Source CID: 64

Quoted 1 line

ACL Data RX: Handle 256 flags 0x02 dlen 12 #73 [hci0] 59.192714

L2CAP: Disconnection Response (0x07) ident 4 len 4
Destination CID: 64
Source CID: 64

btmon after patch:

Quoted 1 line

ACL Data RX: Handle 256 flags 0x02 dlen 16 #248 [hci0] 103.502970

      L2CAP: Connection Response (0x03) ident 5 len 8
        Destination CID: 65
        Source CID: 65
        Result: Connection pending (0x0001)
        Status: No further information available (0x0000)
Quoted 1 line

ACL Data RX: Handle 256 flags 0x02 dlen 16 #249 [hci0] 103.504184

      L2CAP: Connection Response (0x03) ident 5 len 8
        Destination CID: 65
        Source CID: 65
        Result: Connection successful (0x0000)
        Status: No further information available (0x0000)

< ACL Data TX: Handle 256 flags 0x00 dlen 23 #250 [hci0] 103.504398
L2CAP: Configure Request (0x04) ident 6 len 15
Destination CID: 65
Flags: 0x0000
Option: Retransmission and Flow Control (0x04) [mandatory]
Mode: Basic (0x00)
TX window size: 0
Max transmit: 0
Retransmission timeout: 0
Monitor timeout: 0
Maximum PDU size: 0

Quoted 1 line

ACL Data RX: Handle 256 flags 0x02 dlen 16 #251 [hci0] 103.505472

      L2CAP: Configure Request (0x04) ident 3 len 8
        Destination CID: 65
        Flags: 0x0000
        Option: Maximum Transmission Unit (0x01) [mandatory]
          MTU: 1480
< ACL Data TX: Handle 256 flags 0x00 dlen 18                          #252 [hci0] 103.505689
      L2CAP: Configure Response (0x05) ident 3 len 10
        Source CID: 65
        Flags: 0x0000
        Result: Success (0x0000)
        Option: Maximum Transmission Unit (0x01) [mandatory]
          MTU: 1480
Quoted 1 line

ACL Data RX: Handle 256 flags 0x02 dlen 15 #254 [hci0] 103.509165

      L2CAP: Configure Response (0x05) ident 6 len 7
        Source CID: 65
        Flags: 0x0000
        Result: Failure - unknown options (0x0003)
        04                                               .
< ACL Data TX: Handle 256 flags 0x00 dlen 12                          #255 [hci0] 103.509426
      L2CAP: Configure Request (0x04) ident 7 len 4
        Destination CID: 65
        Flags: 0x0000
< ACL Data TX: Handle 256 flags 0x00 dlen 12                          #257 [hci0] 103.511870
      L2CAP: Connection Request (0x02) ident 8 len 4
        PSM: 1 (0x0001)
        Source CID: 66
Quoted 8 lines
Quoted 1 line

ACL Data RX: Handle 256 flags 0x02 dlen 14 #259 [hci0] 103.514121

      L2CAP: Configure Response (0x05) ident 7 len 6
        Source CID: 65
        Flags: 0x0000
        Result: Success (0x0000)
Signed-off-by Florian Dollinger <[email protected]>
Co-developed-by Florian Dollinger <[email protected]>
Reviewed-by Luiz Augusto Von Dentz <[email protected]>
Quoted 19 lines
---
 net/bluetooth/l2cap_core.c | 1 +
 1 file changed, 1 insertion(+)
net/bluetooth/l2cap_core.c +1 -1
index 1ab27b90ddcb..3ab95ea2cd80 100644
@@ -4513,6 +4513,7 @@ static inline int l2cap_config_rsp(struct l2cap_conn *conn,
                }
                goto done;
 
+       case L2CAP_CONF_UNKNOWN:
        case L2CAP_CONF_UNACCEPT:
                if (chan->num_conf_rsp <= L2CAP_CONF_MAX_CONF_RSP) {
                        char req[64];
--

2.29.2

Signature · 1 line
Luiz Augusto von Dentz
author
#11 lore raw
Quoted 13 lines · Luiz Augusto von Dentz

Hi,

Quoted 9 lines · Bastien Nocera

The current implementation of L2CAP options negotiation will continue
the negotiation when a device responds with L2CAP_CONF_UNACCEPT ("unaccepted
options"), but not when the device replies with L2CAP_CONF_UNKNOWN ("unknown
options").

Quoted 6 lines
Quoted 4 lines

Trying to continue the negotiation without ERTM support will allow Bluetooth-capable XBox One controllers (notably models 1708 and 1797)
to connect.

<snip>

Reviewed-by Luiz Augusto Von Dentz <[email protected]>

Marcel? Anything else that would need to be done to land this?

Cheers

author
#12 lore raw
In reply to Luiz Augusto von Dentz
Quoted 18 lines · Luiz Augusto von Dentz

Hi,

Quoted 14 lines · Bastien Nocera

The current implementation of L2CAP options negotiation will continue
the negotiation when a device responds with L2CAP_CONF_UNACCEPT ("unaccepted
options"), but not when the device replies with L2CAP_CONF_UNKNOWN ("unknown
options").

Trying to continue the negotiation without ERTM support will allow Bluetooth-capable XBox One controllers (notably models 1708 and 1797)
to connect.

Quoted 5 lines
Quoted 3 lines

<snip>

Signed-off-by Florian Dollinger <[email protected]>
Co-developed-by Florian Dollinger <[email protected]>
Reviewed-by Luiz Augusto Von Dentz <[email protected]>

Marcel, any chance of a review on this one? I've sent you the results of the PTS tests privately, but looks like you weren't CC:ed on the earlier mail thread.

Cheers

author
#13 lore raw
Quoted 5 lines · Bastien Nocera

<snip>
Marcel, any chance of a review on this one? I've sent you the results
of the PTS tests privately, but looks like you weren't CC:ed on the earlier mail thread.

Our e-mails only just crossed paths.

Thanks for merging it!

maintainer
#14 lore raw
In reply to Bastien Nocera

Hi Bastien,

Quoted 112 lines

The current implementation of L2CAP options negotiation will continue the negotiation when a device responds with L2CAP_CONF_UNACCEPT ("unaccepted options"), but not when the device replies with L2CAP_CONF_UNKNOWN ("unknown options").

Trying to continue the negotiation without ERTM support will allow Bluetooth-capable XBox One controllers (notably models 1708 and 1797) to connect.

btmon before patch:

Quoted 1 line

ACL Data RX: Handle 256 flags 0x02 dlen 16 #64 [hci0] 59.182702

     L2CAP: Connection Response (0x03) ident 2 len 8
       Destination CID: 64
       Source CID: 64
       Result: Connection successful (0x0000)
       Status: No further information available (0x0000)

< ACL Data TX: Handle 256 flags 0x00 dlen 23 #65 [hci0] 59.182744
L2CAP: Configure Request (0x04) ident 3 len 15
Destination CID: 64
Flags: 0x0000
Option: Retransmission and Flow Control (0x04) [mandatory]
Mode: Basic (0x00)
TX window size: 0
Max transmit: 0
Retransmission timeout: 0
Monitor timeout: 0
Maximum PDU size: 0

Quoted 1 line

ACL Data RX: Handle 256 flags 0x02 dlen 16 #66 [hci0] 59.183948

     L2CAP: Configure Request (0x04) ident 1 len 8
       Destination CID: 64
       Flags: 0x0000
       Option: Maximum Transmission Unit (0x01) [mandatory]
         MTU: 1480
< ACL Data TX: Handle 256 flags 0x00 dlen 18                            #67 [hci0] 59.183994
     L2CAP: Configure Response (0x05) ident 1 len 10
       Source CID: 64
       Flags: 0x0000
       Result: Success (0x0000)
       Option: Maximum Transmission Unit (0x01) [mandatory]
         MTU: 1480
Quoted 1 line

ACL Data RX: Handle 256 flags 0x02 dlen 15 #69 [hci0] 59.187676

     L2CAP: Configure Response (0x05) ident 3 len 7
       Source CID: 64
       Flags: 0x0000
       Result: Failure - unknown options (0x0003)
       04                                               .

< ACL Data TX: Handle 256 flags 0x00 dlen 12 #70 [hci0] 59.187722
L2CAP: Disconnection Request (0x06) ident 4 len 4
Destination CID: 64
Source CID: 64

Quoted 1 line

ACL Data RX: Handle 256 flags 0x02 dlen 12 #73 [hci0] 59.192714

L2CAP: Disconnection Response (0x07) ident 4 len 4
Destination CID: 64
Source CID: 64

btmon after patch:

Quoted 1 line

ACL Data RX: Handle 256 flags 0x02 dlen 16 #248 [hci0] 103.502970

     L2CAP: Connection Response (0x03) ident 5 len 8
       Destination CID: 65
       Source CID: 65
       Result: Connection pending (0x0001)
       Status: No further information available (0x0000)
Quoted 1 line

ACL Data RX: Handle 256 flags 0x02 dlen 16 #249 [hci0] 103.504184

     L2CAP: Connection Response (0x03) ident 5 len 8
       Destination CID: 65
       Source CID: 65
       Result: Connection successful (0x0000)
       Status: No further information available (0x0000)

< ACL Data TX: Handle 256 flags 0x00 dlen 23 #250 [hci0] 103.504398
L2CAP: Configure Request (0x04) ident 6 len 15
Destination CID: 65
Flags: 0x0000
Option: Retransmission and Flow Control (0x04) [mandatory]
Mode: Basic (0x00)
TX window size: 0
Max transmit: 0
Retransmission timeout: 0
Monitor timeout: 0
Maximum PDU size: 0

Quoted 1 line

ACL Data RX: Handle 256 flags 0x02 dlen 16 #251 [hci0] 103.505472

     L2CAP: Configure Request (0x04) ident 3 len 8
       Destination CID: 65
       Flags: 0x0000
       Option: Maximum Transmission Unit (0x01) [mandatory]
         MTU: 1480
< ACL Data TX: Handle 256 flags 0x00 dlen 18                          #252 [hci0] 103.505689
     L2CAP: Configure Response (0x05) ident 3 len 10
       Source CID: 65
       Flags: 0x0000
       Result: Success (0x0000)
       Option: Maximum Transmission Unit (0x01) [mandatory]
         MTU: 1480
Quoted 1 line

ACL Data RX: Handle 256 flags 0x02 dlen 15 #254 [hci0] 103.509165

     L2CAP: Configure Response (0x05) ident 6 len 7
       Source CID: 65
       Flags: 0x0000
       Result: Failure - unknown options (0x0003)
       04                                               .
< ACL Data TX: Handle 256 flags 0x00 dlen 12                          #255 [hci0] 103.509426
     L2CAP: Configure Request (0x04) ident 7 len 4
       Destination CID: 65
       Flags: 0x0000
< ACL Data TX: Handle 256 flags 0x00 dlen 12                          #257 [hci0] 103.511870
     L2CAP: Connection Request (0x02) ident 8 len 4
       PSM: 1 (0x0001)
       Source CID: 66
Quoted 1 line

ACL Data RX: Handle 256 flags 0x02 dlen 14 #259 [hci0] 103.514121

     L2CAP: Configure Response (0x05) ident 7 len 6
       Source CID: 65
       Flags: 0x0000
       Result: Success (0x0000)
Quoted 5 lines
Signed-off-by Florian Dollinger <[email protected]>
Co-developed-by Florian Dollinger <[email protected]>

---
net/bluetooth/l2cap_core.c | 1 +

1 file changed, 1 insertion(+)

patch has been applied to bluetooth-next tree.

Regards

Marcel