[PATCH] Bluetooth: Fix null pointer deref on unexpected status event

[PATCH] Bluetooth: Fix null pointer deref on unexpected status event

[Soenke Huster]

__hci_cmd_sync returns NULL if the controller responds with a status
event. This is unexpected for the commands sent here, but on
occurrence leads to null pointer dereferences and thus must be
handled.

Signed-off-by: Soenke Huster <soenke.huster@eknoes.de>
---
 net/bluetooth/aosp.c | 15 ++++++++++++---
 net/bluetooth/msft.c | 15 ++++++++++++---
 2 files changed, 24 insertions(+), 6 deletions(-)

diff --git a/net/bluetooth/aosp.c b/net/bluetooth/aosp.c
index 432ae3aac9e3..1d67836e95e1 100644
--- a/net/bluetooth/aosp.c
+++ b/net/bluetooth/aosp.c
@@ -54,7 +54,10 @@ void aosp_do_open(struct hci_dev *hdev)
 	/* LE Get Vendor Capabilities Command */
 	skb = __hci_cmd_sync(hdev, hci_opcode_pack(0x3f, 0x153), 0, NULL,
 			     HCI_CMD_TIMEOUT);
-	if (IS_ERR(skb)) {
+	if (IS_ERR_OR_NULL(skb)) {
+		if (!skb)
+			skb = ERR_PTR(-EIO);
+
 		bt_dev_err(hdev, "AOSP get vendor capabilities (%ld)",
 			   PTR_ERR(skb));
 		return;
@@ -152,7 +155,10 @@ static int enable_quality_report(struct hci_dev *hdev)
 
 	skb = __hci_cmd_sync(hdev, BQR_OPCODE, sizeof(cp), &cp,
 			     HCI_CMD_TIMEOUT);
-	if (IS_ERR(skb)) {
+	if (IS_ERR_OR_NULL(skb)) {
+		if (!skb)
+			skb = ERR_PTR(-EIO);
+
 		bt_dev_err(hdev, "Enabling Android BQR failed (%ld)",
 			   PTR_ERR(skb));
 		return PTR_ERR(skb);
@@ -171,7 +177,10 @@ static int disable_quality_report(struct hci_dev *hdev)
 
 	skb = __hci_cmd_sync(hdev, BQR_OPCODE, sizeof(cp), &cp,
 			     HCI_CMD_TIMEOUT);
-	if (IS_ERR(skb)) {
+	if (IS_ERR_OR_NULL(skb)) {
+		if (!skb)
+			skb = ERR_PTR(-EIO);
+
 		bt_dev_err(hdev, "Disabling Android BQR failed (%ld)",
 			   PTR_ERR(skb));
 		return PTR_ERR(skb);
diff --git a/net/bluetooth/msft.c b/net/bluetooth/msft.c
index 14975769f678..bee6a4c656be 100644
--- a/net/bluetooth/msft.c
+++ b/net/bluetooth/msft.c
@@ -120,7 +120,10 @@ static bool read_supported_features(struct hci_dev *hdev,
 
 	skb = __hci_cmd_sync(hdev, hdev->msft_opcode, sizeof(cp), &cp,
 			     HCI_CMD_TIMEOUT);
-	if (IS_ERR(skb)) {
+	if (IS_ERR_OR_NULL(skb)) {
+		if (!skb)
+			skb = ERR_PTR(-EIO);
+
 		bt_dev_err(hdev, "Failed to read MSFT supported features (%ld)",
 			   PTR_ERR(skb));
 		return false;
@@ -319,8 +322,11 @@ static int msft_remove_monitor_sync(struct hci_dev *hdev,
 
 	skb = __hci_cmd_sync(hdev, hdev->msft_opcode, sizeof(cp), &cp,
 			     HCI_CMD_TIMEOUT);
-	if (IS_ERR(skb))
+	if (IS_ERR_OR_NULL(skb)) {
+		if (!skb)
+			return -EIO;
 		return PTR_ERR(skb);
+	}
 
 	return msft_le_cancel_monitor_advertisement_cb(hdev, hdev->msft_opcode,
 						       monitor, skb);
@@ -432,8 +438,11 @@ static int msft_add_monitor_sync(struct hci_dev *hdev,
 			     HCI_CMD_TIMEOUT);
 	kfree(cp);
 
-	if (IS_ERR(skb))
+	if (IS_ERR_OR_NULL(skb)) {
+		if (!skb)
+			return -EIO;
 		return PTR_ERR(skb);
+	}
 
 	return msft_le_monitor_advertisement_cb(hdev, hdev->msft_opcode,
 						monitor, skb);
-- 
2.37.1

RE: Bluetooth: Fix null pointer deref on unexpected status event

[bluez.test.bot]

[-- Attachment #1: Type: text/plain, Size: 1100 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=662224

---Test result---

Test Summary:
CheckPatch                    PASS      1.51 seconds
GitLint                       PASS      0.77 seconds
SubjectPrefix                 PASS      0.61 seconds
BuildKernel                   PASS      44.25 seconds
BuildKernel32                 PASS      38.64 seconds
Incremental Build with patchesPASS      65.34 seconds
TestRunner: Setup             PASS      672.66 seconds
TestRunner: l2cap-tester      PASS      20.59 seconds
TestRunner: bnep-tester       PASS      7.63 seconds
TestRunner: mgmt-tester       PASS      125.34 seconds
TestRunner: rfcomm-tester     PASS      11.56 seconds
TestRunner: sco-tester        PASS      11.17 seconds
TestRunner: smp-tester        PASS      11.05 seconds
TestRunner: userchan-tester   PASS      7.51 seconds



---
Regards,
Linux Bluetooth

Re: [PATCH] Bluetooth: Fix null pointer deref on unexpected status event

[patchwork-bot+bluetooth]

Hello:

This patch was applied to bluetooth/bluetooth-next.git (master)
by Luiz Augusto von Dentz <luiz.von.dentz@intel.com>:

On Fri, 22 Jul 2022 13:53:07 +0200 you wrote:
> __hci_cmd_sync returns NULL if the controller responds with a status
> event. This is unexpected for the commands sent here, but on
> occurrence leads to null pointer dereferences and thus must be
> handled.
> 
> Signed-off-by: Soenke Huster <soenke.huster@eknoes.de>
> 
> [...]

Here is the summary with links:
  - Bluetooth: Fix null pointer deref on unexpected status event
    https://git.kernel.org/bluetooth/bluetooth-next/c/aa7c99c75eea

You are awesome, thank you!
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