[PATCH] Bluetooth: btintel_pcie: fix off-by-one in RX queue bounds check

[PATCH] Bluetooth: btintel_pcie: fix off-by-one in RX queue bounds check

[Junrui Luo]

btintel_pcie_submit_rx() reads frbd_index and validates it against
rxq->count. Since rxq->frbds[] and rxq->bufs[] are allocated with
rxq->count entries, valid indices are 0 to rxq->count - 1. The current
check uses > instead of >=, allowing frbd_index == rxq->count through.

This causes an out-of-bounds access in btintel_pcie_prepare_rx() when
writing to rxq->bufs[frbd_index] and rxq->frbds[frbd_index].

Fix by using >= so that frbd_index == rxq->count is correctly rejected.

Fixes: c2b636b3f788 ("Bluetooth: btintel_pcie: Add support for PCIe transport")
Reported-by: Yuhao Jiang <danisjiang@gmail.com>
Cc: stable@vger.kernel.org
Signed-off-by: Junrui Luo <moonafterrain@outlook.com>
---
 drivers/bluetooth/btintel_pcie.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/bluetooth/btintel_pcie.c b/drivers/bluetooth/btintel_pcie.c
index 37b744e35bc4..cbadcfe86321 100644
--- a/drivers/bluetooth/btintel_pcie.c
+++ b/drivers/bluetooth/btintel_pcie.c
@@ -460,7 +460,7 @@ static int btintel_pcie_submit_rx(struct btintel_pcie_data *data)
 
 	frbd_index = data->ia.tr_hia[BTINTEL_PCIE_RXQ_NUM];
 
-	if (frbd_index > rxq->count)
+	if (frbd_index >= rxq->count)
 		return -ERANGE;
 
 	/* Prepare for RX submit. It updates the FRBD with the address of DMA

---
base-commit: c369299895a591d96745d6492d4888259b004a9e
change-id: 20260324-fixes-8c301e8881f0

Best regards,
-- 
Junrui Luo <moonafterrain@outlook.com>

RE: Bluetooth: btintel_pcie: fix off-by-one in RX queue bounds check

[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=1071681

---Test result---

Test Summary:
CheckPatch                    PENDING   0.59 seconds
GitLint                       PENDING   0.33 seconds
SubjectPrefix                 PASS      0.10 seconds
BuildKernel                   PASS      27.00 seconds
CheckAllWarning               PASS      29.30 seconds
CheckSparse                   PASS      28.00 seconds
BuildKernel32                 PASS      26.06 seconds
TestRunnerSetup               PASS      578.23 seconds
TestRunner_l2cap-tester       PASS      28.23 seconds
TestRunner_iso-tester         FAIL      37.46 seconds
TestRunner_bnep-tester        PASS      6.51 seconds
TestRunner_mgmt-tester        FAIL      137.01 seconds
TestRunner_rfcomm-tester      PASS      9.83 seconds
TestRunner_sco-tester         FAIL      14.82 seconds
TestRunner_ioctl-tester       PASS      10.45 seconds
TestRunner_mesh-tester        FAIL      12.67 seconds
TestRunner_smp-tester         PASS      8.82 seconds
TestRunner_userchan-tester    PASS      6.89 seconds
IncrementalBuild              PENDING   0.51 seconds

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

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

##############################
Test: TestRunner_iso-tester - FAIL
Desc: Run iso-tester with test-runner
Output:
BUG: KASAN: slab-use-after-free in le_read_features_complete+0x7e/0x2b0
Total: 141, Passed: 141 (100.0%), Failed: 0, Not Run: 0
##############################
Test: TestRunner_mgmt-tester - FAIL
Desc: Run mgmt-tester with test-runner
Output:
Total: 494, Passed: 488 (98.8%), Failed: 2, Not Run: 4

Failed Test Cases
Read Exp Feature - Success                           Failed       0.112 seconds
LL Privacy - Set Flags 3 (2 Devices to RL)           Failed       0.204 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    2.724 seconds
Mesh - Send cancel - 2                               Timed out    1.994 seconds
##############################
Test: IncrementalBuild - PENDING
Desc: Incremental build with the patches in the series
Output:



---
Regards,
Linux Bluetooth

Re: [PATCH] Bluetooth: btintel_pcie: fix off-by-one in RX queue bounds check

[Luiz Augusto von Dentz]

Hi @Kiran K

On Tue, Mar 24, 2026 at 9:27 AM Junrui Luo <moonafterrain@outlook.com> wrote:
>
> btintel_pcie_submit_rx() reads frbd_index and validates it against
> rxq->count. Since rxq->frbds[] and rxq->bufs[] are allocated with
> rxq->count entries, valid indices are 0 to rxq->count - 1. The current
> check uses > instead of >=, allowing frbd_index == rxq->count through.
>
> This causes an out-of-bounds access in btintel_pcie_prepare_rx() when
> writing to rxq->bufs[frbd_index] and rxq->frbds[frbd_index].
>
> Fix by using >= so that frbd_index == rxq->count is correctly rejected.
>
> Fixes: c2b636b3f788 ("Bluetooth: btintel_pcie: Add support for PCIe transport")
> Reported-by: Yuhao Jiang <danisjiang@gmail.com>
> Cc: stable@vger.kernel.org
> Signed-off-by: Junrui Luo <moonafterrain@outlook.com>
> ---
>  drivers/bluetooth/btintel_pcie.c | 2 +-
>  1 file changed, 1 insertion(+), 1 deletion(-)
>
> diff --git a/drivers/bluetooth/btintel_pcie.c b/drivers/bluetooth/btintel_pcie.c
> index 37b744e35bc4..cbadcfe86321 100644
> --- a/drivers/bluetooth/btintel_pcie.c
> +++ b/drivers/bluetooth/btintel_pcie.c
> @@ -460,7 +460,7 @@ static int btintel_pcie_submit_rx(struct btintel_pcie_data *data)
>
>         frbd_index = data->ia.tr_hia[BTINTEL_PCIE_RXQ_NUM];
>
> -       if (frbd_index > rxq->count)
> +       if (frbd_index >= rxq->count)
>                 return -ERANGE;
>
>         /* Prepare for RX submit. It updates the FRBD with the address of DMA
>
> ---
> base-commit: c369299895a591d96745d6492d4888259b004a9e
> change-id: 20260324-fixes-8c301e8881f0
>
> Best regards,
> --
> Junrui Luo <moonafterrain@outlook.com>

This one seems valid as well.

-- 
Luiz Augusto von Dentz