[PATCH] Bluetooth: Fix eir name length

[PATCH] Bluetooth: Fix eir name length

[Frédéric Danis]

According to Section 1.2 of Core Specification Supplement Part A the
complete or short name strings are defined as utf8s, which should not
include the trailing NULL for variable length array as defined in Core
Specification Vol1 Part E Section 2.9.3.

The trailing NULL was introduce by commit f61851f64b17
("Bluetooth: Fix append max 11 bytes of name to scan rsp data")

Removing the trailing NULL allows PTS to retrieve the random address based
on device name, e.g. for SM/PER/KDU/BV-02-C, SM/PER/KDU/BV-08-C or
GAP/BROB/BCST/BV-03-C.

Signed-off-by: Frédéric Danis <frederic.danis@collabora.com>
---
 net/bluetooth/eir.c  | 29 +++++++----------------------
 net/bluetooth/mgmt.c |  2 +-
 2 files changed, 8 insertions(+), 23 deletions(-)

diff --git a/net/bluetooth/eir.c b/net/bluetooth/eir.c
index 9214189279e8..1bc51e2b05a3 100644
--- a/net/bluetooth/eir.c
+++ b/net/bluetooth/eir.c
@@ -13,48 +13,33 @@
 
 #define PNP_INFO_SVCLASS_ID		0x1200
 
-static u8 eir_append_name(u8 *eir, u16 eir_len, u8 type, u8 *data, u8 data_len)
-{
-	u8 name[HCI_MAX_SHORT_NAME_LENGTH + 1];
-
-	/* If data is already NULL terminated just pass it directly */
-	if (data[data_len - 1] == '\0')
-		return eir_append_data(eir, eir_len, type, data, data_len);
-
-	memcpy(name, data, HCI_MAX_SHORT_NAME_LENGTH);
-	name[HCI_MAX_SHORT_NAME_LENGTH] = '\0';
-
-	return eir_append_data(eir, eir_len, type, name, sizeof(name));
-}
-
 u8 eir_append_local_name(struct hci_dev *hdev, u8 *ptr, u8 ad_len)
 {
 	size_t short_len;
 	size_t complete_len;
 
-	/* no space left for name (+ NULL + type + len) */
-	if ((max_adv_len(hdev) - ad_len) < HCI_MAX_SHORT_NAME_LENGTH + 3)
+	/* no space left for name (+ type + len) */
+	if ((max_adv_len(hdev) - ad_len) < HCI_MAX_SHORT_NAME_LENGTH + 2)
 		return ad_len;
 
 	/* use complete name if present and fits */
 	complete_len = strnlen(hdev->dev_name, sizeof(hdev->dev_name));
 	if (complete_len && complete_len <= HCI_MAX_SHORT_NAME_LENGTH)
-		return eir_append_name(ptr, ad_len, EIR_NAME_COMPLETE,
-				       hdev->dev_name, complete_len + 1);
+		return eir_append_data(ptr, ad_len, EIR_NAME_COMPLETE,
+				       hdev->dev_name, complete_len);
 
 	/* use short name if present */
 	short_len = strnlen(hdev->short_name, sizeof(hdev->short_name));
 	if (short_len)
-		return eir_append_name(ptr, ad_len, EIR_NAME_SHORT,
+		return eir_append_data(ptr, ad_len, EIR_NAME_SHORT,
 				       hdev->short_name,
-				       short_len == HCI_MAX_SHORT_NAME_LENGTH ?
-				       short_len : short_len + 1);
+				       short_len);
 
 	/* use shortened full name if present, we already know that name
 	 * is longer then HCI_MAX_SHORT_NAME_LENGTH
 	 */
 	if (complete_len)
-		return eir_append_name(ptr, ad_len, EIR_NAME_SHORT,
+		return eir_append_data(ptr, ad_len, EIR_NAME_SHORT,
 				       hdev->dev_name,
 				       HCI_MAX_SHORT_NAME_LENGTH);
 
diff --git a/net/bluetooth/mgmt.c b/net/bluetooth/mgmt.c
index 9613cc8a60f8..32ed6e9245a3 100644
--- a/net/bluetooth/mgmt.c
+++ b/net/bluetooth/mgmt.c
@@ -8408,7 +8408,7 @@ static int read_adv_features(struct sock *sk, struct hci_dev *hdev,
 
 static u8 calculate_name_len(struct hci_dev *hdev)
 {
-	u8 buf[HCI_MAX_SHORT_NAME_LENGTH + 3];
+	u8 buf[HCI_MAX_SHORT_NAME_LENGTH + 2]; /* len + type + name */
 
 	return eir_append_local_name(hdev, buf, 0);
 }
-- 
2.34.1

RE: Bluetooth: Fix eir name length

[bluez.test.bot]

[-- Attachment #1: Type: text/plain, Size: 2843 bytes --]

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=833441

---Test result---

Test Summary:
CheckPatch                    PASS      1.49 seconds
GitLint                       PASS      0.58 seconds
SubjectPrefix                 PASS      0.20 seconds
BuildKernel                   PASS      27.83 seconds
CheckAllWarning               PASS      30.87 seconds
CheckSparse                   PASS      36.08 seconds
CheckSmatch                   PASS      99.59 seconds
BuildKernel32                 PASS      27.28 seconds
TestRunnerSetup               PASS      513.19 seconds
TestRunner_l2cap-tester       PASS      20.14 seconds
TestRunner_iso-tester         FAIL      32.72 seconds
TestRunner_bnep-tester        PASS      4.75 seconds
TestRunner_mgmt-tester        FAIL      112.10 seconds
TestRunner_rfcomm-tester      PASS      7.33 seconds
TestRunner_sco-tester         PASS      14.92 seconds
TestRunner_ioctl-tester       PASS      7.80 seconds
TestRunner_mesh-tester        PASS      6.68 seconds
TestRunner_smp-tester         PASS      6.86 seconds
TestRunner_userchan-tester    PASS      4.94 seconds
IncrementalBuild              PASS      26.47 seconds

Details
##############################
Test: TestRunner_iso-tester - FAIL
Desc: Run iso-tester with test-runner
Output:
Total: 117, Passed: 116 (99.1%), Failed: 1, Not Run: 0

Failed Test Cases
ISO Connect2 Suspend - Success                       Failed       6.233 seconds
##############################
Test: TestRunner_mgmt-tester - FAIL
Desc: Run mgmt-tester with test-runner
Output:
Total: 492, Passed: 478 (97.2%), Failed: 12, Not Run: 2

Failed Test Cases
Set Advertising on - Local name 1                    Failed       0.103 seconds
Set Advertising on - Name + Appear 1                 Failed       2.149 seconds
Add Advertising - Success (Complete name)            Failed       0.105 seconds
Add Advertising - Success (Shortened name)           Failed       0.101 seconds
Add Advertising - Success (Short name)               Failed       0.100 seconds
Add Advertising - Success (Name + data)              Failed       0.105 seconds
Add Advertising - Success (Name+data+appear)         Failed       0.109 seconds
Add Ext Advertising - Success (Complete name)        Failed       0.108 seconds
Add Ext Advertising - Success (Shortened name)       Failed       0.108 seconds
Add Ext Advertising - Success (Short name)           Failed       0.102 seconds
Add Ext Advertising - Success (Name + data)          Failed       0.105 seconds
Add Ext Advertising - Success (Name+data+appear)     Failed       0.113 seconds


---
Regards,
Linux Bluetooth