[PATCH] Bluetooth: ISO: validate ISO_END fragments

[PATCH] Bluetooth: ISO: validate ISO_END fragments

[Kangzheng Gu]

A malformed ISO_END fragment can trigger a NULL pointer dereference
due to missing validation before processing. An oversized end fragment
should also be rejected.

Add the same validation for ISO_END as for ISO_CONT, and reset the
in-progress reassembly state when malformed input is detected.

Fixes: ccf74f2390d6 ("Bluetooth: Add BTPROTO_ISO socket type")
Cc: stable@vger.kernel.org
Signed-off-by: Kangzheng Gu <xiaoguai0992@gmail.com>
---
 net/bluetooth/iso.c | 21 +++++++++++++++++++++
 1 file changed, 21 insertions(+)

diff --git a/net/bluetooth/iso.c b/net/bluetooth/iso.c
index be145e2736b7..8707f3c4b103 100644
--- a/net/bluetooth/iso.c
+++ b/net/bluetooth/iso.c
@@ -2587,6 +2587,27 @@ int iso_recv(struct hci_dev *hdev, u16 handle, struct sk_buff *skb, u16 flags)
 		break;
 
 	case ISO_END:
+		BT_DBG("End: frag len %d (expecting %d)", skb->len,
+		       conn->rx_len);
+
+		if (!conn->rx_len) {
+			BT_ERR("Unexpected end frame (len %d)",
+			       skb->len);
+			kfree_skb(conn->rx_skb);
+			conn->rx_skb = NULL;
+			conn->rx_len = 0;
+			goto drop;
+		}
+
+		if (skb->len > conn->rx_len) {
+			BT_ERR("Fragment is too long (len %d, expected %d)",
+			       skb->len, conn->rx_len);
+			kfree_skb(conn->rx_skb);
+			conn->rx_skb = NULL;
+			conn->rx_len = 0;
+			goto drop;
+		}
+
 		skb_copy_from_linear_data(skb, skb_put(conn->rx_skb, skb->len),
 					  skb->len);
 		conn->rx_len -= skb->len;
-- 
2.50.1

RE: Bluetooth: ISO: validate ISO_END fragments

[bluez.test.bot]

[-- Attachment #1: Type: text/plain, Size: 2913 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=1074052

---Test result---

Test Summary:
CheckPatch                    PENDING   0.25 seconds
GitLint                       PENDING   0.20 seconds
SubjectPrefix                 PASS      0.12 seconds
BuildKernel                   PASS      26.03 seconds
CheckAllWarning               PASS      28.36 seconds
CheckSparse                   PASS      27.30 seconds
BuildKernel32                 PASS      26.91 seconds
TestRunnerSetup               PASS      567.23 seconds
TestRunner_l2cap-tester       PASS      27.98 seconds
TestRunner_iso-tester         PASS      35.49 seconds
TestRunner_bnep-tester        PASS      6.46 seconds
TestRunner_mgmt-tester        FAIL      114.56 seconds
TestRunner_rfcomm-tester      PASS      9.50 seconds
TestRunner_sco-tester         FAIL      14.27 seconds
TestRunner_ioctl-tester       PASS      10.11 seconds
TestRunner_mesh-tester        FAIL      11.42 seconds
TestRunner_smp-tester         PASS      8.63 seconds
TestRunner_userchan-tester    PASS      6.69 seconds
IncrementalBuild              PENDING   0.53 seconds

Details
##############################
Test: CheckPatch - PENDING
Desc: Run checkpatch.pl script
Output:

##############################
Test: GitLint - PENDING
Desc: Run gitlint
Output:

##############################
Test: TestRunner_mgmt-tester - FAIL
Desc: Run mgmt-tester with test-runner
Output:
Total: 494, Passed: 485 (98.2%), Failed: 5, Not Run: 4

Failed Test Cases
Adv. connectable & connected (central) - Success     Failed       0.131 seconds
Adv. non-connectable & connected (central) - Success Failed       0.129 seconds
Ext Adv. connectable & connected (central)           Failed       0.180 seconds
Ext Adv. non-connectable & connected (central)       Failed       0.184 seconds
Read Exp Feature - Success                           Failed       0.115 seconds
##############################
Test: TestRunner_sco-tester - FAIL
Desc: Run sco-tester with test-runner
Output:
WARNING: possible circular locking dependency detected
BUG: sleeping function called from invalid context at net/core/sock.c:3782
Total: 30, Passed: 30 (100.0%), Failed: 0, Not Run: 0
##############################
Test: TestRunner_mesh-tester - FAIL
Desc: Run mesh-tester with test-runner
Output:
Total: 10, Passed: 8 (80.0%), Failed: 2, Not Run: 0

Failed Test Cases
Mesh - Send cancel - 1                               Timed out    1.875 seconds
Mesh - Send cancel - 2                               Timed out    2.001 seconds
##############################
Test: IncrementalBuild - PENDING
Desc: Incremental build with the patches in the series
Output:



---
Regards,
Linux Bluetooth