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From: Sasha Levin <sashal@kernel.org>
To: linux-kernel@vger.kernel.org, stable@vger.kernel.org
Cc: "João Paulo Rechi Vita" <jprvita@gmail.com>,
	"João Paulo Rechi Vita" <jprvita@endlessm.com>,
	"Marcel Holtmann" <marcel@holtmann.org>,
	"Sasha Levin" <sashal@kernel.org>,
	linux-bluetooth@vger.kernel.org, netdev@vger.kernel.org
Subject: [PATCH AUTOSEL 4.19 015/244] Bluetooth: Ignore CC events not matching the last HCI command
Date: Wed, 22 May 2019 15:22:41 -0400	[thread overview]
Message-ID: <20190522192630.24917-15-sashal@kernel.org> (raw)
In-Reply-To: <20190522192630.24917-1-sashal@kernel.org>

From: João Paulo Rechi Vita <jprvita@gmail.com>

[ Upstream commit f80c5dad7b6467b884c445ffea45985793b4b2d0 ]

This commit makes the kernel not send the next queued HCI command until
a command complete arrives for the last HCI command sent to the
controller. This change avoids a problem with some buggy controllers
(seen on two SKUs of QCA9377) that send an extra command complete event
for the previous command after the kernel had already sent a new HCI
command to the controller.

The problem was reproduced when starting an active scanning procedure,
where an extra command complete event arrives for the LE_SET_RANDOM_ADDR
command. When this happends the kernel ends up not processing the
command complete for the following commmand, LE_SET_SCAN_PARAM, and
ultimately behaving as if a passive scanning procedure was being
performed, when in fact controller is performing an active scanning
procedure. This makes it impossible to discover BLE devices as no device
found events are sent to userspace.

This problem is reproducible on 100% of the attempts on the affected
controllers. The extra command complete event can be seen at timestamp
27.420131 on the btmon logs bellow.

Bluetooth monitor ver 5.50
= Note: Linux version 5.0.0+ (x86_64)                                  0.352340
= Note: Bluetooth subsystem version 2.22                               0.352343
= New Index: 80:C5:F2:8F:87:84 (Primary,USB,hci0)               [hci0] 0.352344
= Open Index: 80:C5:F2:8F:87:84                                 [hci0] 0.352345
= Index Info: 80:C5:F2:8F:87:84 (Qualcomm)                      [hci0] 0.352346
@ MGMT Open: bluetoothd (privileged) version 1.14             {0x0001} 0.352347
@ MGMT Open: btmon (privileged) version 1.14                  {0x0002} 0.352366
@ MGMT Open: btmgmt (privileged) version 1.14                {0x0003} 27.302164
@ MGMT Command: Start Discovery (0x0023) plen 1       {0x0003} [hci0] 27.302310
        Address type: 0x06
          LE Public
          LE Random
< HCI Command: LE Set Random Address (0x08|0x0005) plen 6   #1 [hci0] 27.302496
        Address: 15:60:F2:91:B2:24 (Non-Resolvable)
> HCI Event: Command Complete (0x0e) plen 4                 #2 [hci0] 27.419117
      LE Set Random Address (0x08|0x0005) ncmd 1
        Status: Success (0x00)
< HCI Command: LE Set Scan Parameters (0x08|0x000b) plen 7  #3 [hci0] 27.419244
        Type: Active (0x01)
        Interval: 11.250 msec (0x0012)
        Window: 11.250 msec (0x0012)
        Own address type: Random (0x01)
        Filter policy: Accept all advertisement (0x00)
> HCI Event: Command Complete (0x0e) plen 4                 #4 [hci0] 27.420131
      LE Set Random Address (0x08|0x0005) ncmd 1
        Status: Success (0x00)
< HCI Command: LE Set Scan Enable (0x08|0x000c) plen 2      #5 [hci0] 27.420259
        Scanning: Enabled (0x01)
        Filter duplicates: Enabled (0x01)
> HCI Event: Command Complete (0x0e) plen 4                 #6 [hci0] 27.420969
      LE Set Scan Parameters (0x08|0x000b) ncmd 1
        Status: Success (0x00)
> HCI Event: Command Complete (0x0e) plen 4                 #7 [hci0] 27.421983
      LE Set Scan Enable (0x08|0x000c) ncmd 1
        Status: Success (0x00)
@ MGMT Event: Command Complete (0x0001) plen 4        {0x0003} [hci0] 27.422059
      Start Discovery (0x0023) plen 1
        Status: Success (0x00)
        Address type: 0x06
          LE Public
          LE Random
@ MGMT Event: Discovering (0x0013) plen 2             {0x0003} [hci0] 27.422067
        Address type: 0x06
          LE Public
          LE Random
        Discovery: Enabled (0x01)
@ MGMT Event: Discovering (0x0013) plen 2             {0x0002} [hci0] 27.422067
        Address type: 0x06
          LE Public
          LE Random
        Discovery: Enabled (0x01)
@ MGMT Event: Discovering (0x0013) plen 2             {0x0001} [hci0] 27.422067
        Address type: 0x06
          LE Public
          LE Random
        Discovery: Enabled (0x01)

Signed-off-by: João Paulo Rechi Vita <jprvita@endlessm.com>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
 include/net/bluetooth/hci.h |  1 +
 net/bluetooth/hci_core.c    |  5 +++++
 net/bluetooth/hci_event.c   | 12 ++++++++++++
 net/bluetooth/hci_request.c |  5 +++++
 net/bluetooth/hci_request.h |  1 +
 5 files changed, 24 insertions(+)

diff --git a/include/net/bluetooth/hci.h b/include/net/bluetooth/hci.h
index cdd9f1fe7cfa9..845d947dbae82 100644
--- a/include/net/bluetooth/hci.h
+++ b/include/net/bluetooth/hci.h
@@ -270,6 +270,7 @@ enum {
 	HCI_FORCE_BREDR_SMP,
 	HCI_FORCE_STATIC_ADDR,
 	HCI_LL_RPA_RESOLUTION,
+	HCI_CMD_PENDING,
 
 	__HCI_NUM_FLAGS,
 };
diff --git a/net/bluetooth/hci_core.c b/net/bluetooth/hci_core.c
index a06f030477173..5afd67ef797a6 100644
--- a/net/bluetooth/hci_core.c
+++ b/net/bluetooth/hci_core.c
@@ -4274,6 +4274,9 @@ void hci_req_cmd_complete(struct hci_dev *hdev, u16 opcode, u8 status,
 		return;
 	}
 
+	/* If we reach this point this event matches the last command sent */
+	hci_dev_clear_flag(hdev, HCI_CMD_PENDING);
+
 	/* If the command succeeded and there's still more commands in
 	 * this request the request is not yet complete.
 	 */
@@ -4384,6 +4387,8 @@ static void hci_cmd_work(struct work_struct *work)
 
 		hdev->sent_cmd = skb_clone(skb, GFP_KERNEL);
 		if (hdev->sent_cmd) {
+			if (hci_req_status_pend(hdev))
+				hci_dev_set_flag(hdev, HCI_CMD_PENDING);
 			atomic_dec(&hdev->cmd_cnt);
 			hci_send_frame(hdev, skb);
 			if (test_bit(HCI_RESET, &hdev->flags))
diff --git a/net/bluetooth/hci_event.c b/net/bluetooth/hci_event.c
index 7f800c3480f7a..3e7badb3ac2d5 100644
--- a/net/bluetooth/hci_event.c
+++ b/net/bluetooth/hci_event.c
@@ -3357,6 +3357,12 @@ static void hci_cmd_complete_evt(struct hci_dev *hdev, struct sk_buff *skb,
 	hci_req_cmd_complete(hdev, *opcode, *status, req_complete,
 			     req_complete_skb);
 
+	if (hci_dev_test_flag(hdev, HCI_CMD_PENDING)) {
+		bt_dev_err(hdev,
+			   "unexpected event for opcode 0x%4.4x", *opcode);
+		return;
+	}
+
 	if (atomic_read(&hdev->cmd_cnt) && !skb_queue_empty(&hdev->cmd_q))
 		queue_work(hdev->workqueue, &hdev->cmd_work);
 }
@@ -3464,6 +3470,12 @@ static void hci_cmd_status_evt(struct hci_dev *hdev, struct sk_buff *skb,
 		hci_req_cmd_complete(hdev, *opcode, ev->status, req_complete,
 				     req_complete_skb);
 
+	if (hci_dev_test_flag(hdev, HCI_CMD_PENDING)) {
+		bt_dev_err(hdev,
+			   "unexpected event for opcode 0x%4.4x", *opcode);
+		return;
+	}
+
 	if (atomic_read(&hdev->cmd_cnt) && !skb_queue_empty(&hdev->cmd_q))
 		queue_work(hdev->workqueue, &hdev->cmd_work);
 }
diff --git a/net/bluetooth/hci_request.c b/net/bluetooth/hci_request.c
index e8c9ef1e19227..9448ebd3780a3 100644
--- a/net/bluetooth/hci_request.c
+++ b/net/bluetooth/hci_request.c
@@ -46,6 +46,11 @@ void hci_req_purge(struct hci_request *req)
 	skb_queue_purge(&req->cmd_q);
 }
 
+bool hci_req_status_pend(struct hci_dev *hdev)
+{
+	return hdev->req_status == HCI_REQ_PEND;
+}
+
 static int req_run(struct hci_request *req, hci_req_complete_t complete,
 		   hci_req_complete_skb_t complete_skb)
 {
diff --git a/net/bluetooth/hci_request.h b/net/bluetooth/hci_request.h
index 692cc8b133682..55b2050cc9ff0 100644
--- a/net/bluetooth/hci_request.h
+++ b/net/bluetooth/hci_request.h
@@ -37,6 +37,7 @@ struct hci_request {
 
 void hci_req_init(struct hci_request *req, struct hci_dev *hdev);
 void hci_req_purge(struct hci_request *req);
+bool hci_req_status_pend(struct hci_dev *hdev);
 int hci_req_run(struct hci_request *req, hci_req_complete_t complete);
 int hci_req_run_skb(struct hci_request *req, hci_req_complete_skb_t complete);
 void hci_req_add(struct hci_request *req, u16 opcode, u32 plen,
-- 
2.20.1


  parent reply	other threads:[~2019-05-22 19:49 UTC|newest]

Thread overview: 84+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2019-05-22 19:22 [PATCH AUTOSEL 4.19 001/244] gfs2: Fix lru_count going negative Sasha Levin
2019-05-22 19:22 ` [PATCH AUTOSEL 4.19 002/244] cxgb4: Fix error path in cxgb4_init_module Sasha Levin
2019-05-22 19:22 ` [PATCH AUTOSEL 4.19 003/244] NFS: make nfs_match_client killable Sasha Levin
2019-05-22 19:22 ` [PATCH AUTOSEL 4.19 004/244] IB/hfi1: Fix WQ_MEM_RECLAIM warning Sasha Levin
2019-05-22 19:22 ` [PATCH AUTOSEL 4.19 005/244] gfs2: Fix occasional glock use-after-free Sasha Levin
2019-05-22 19:22 ` [PATCH AUTOSEL 4.19 006/244] mmc: core: Verify SD bus width Sasha Levin
2019-05-22 19:22 ` [PATCH AUTOSEL 4.19 007/244] batman-adv: mcast: fix multicast tt/tvlv worker locking Sasha Levin
2019-05-22 19:22 ` [PATCH AUTOSEL 4.19 008/244] tools/bpf: fix perf build error with uClibc (seen on ARC) Sasha Levin
2019-05-22 19:22 ` [PATCH AUTOSEL 4.19 009/244] selftests/bpf: set RLIMIT_MEMLOCK properly for test_libbpf_open.c Sasha Levin
2019-05-22 19:22 ` [PATCH AUTOSEL 4.19 010/244] bpftool: exclude bash-completion/bpftool from .gitignore pattern Sasha Levin
2019-05-22 19:22 ` [PATCH AUTOSEL 4.19 011/244] dmaengine: tegra210-dma: free dma controller in remove() Sasha Levin
2019-05-22 19:22 ` [PATCH AUTOSEL 4.19 012/244] net: ena: gcc 8: fix compilation warning Sasha Levin
2019-05-22 19:22 ` [PATCH AUTOSEL 4.19 013/244] hv_netvsc: fix race that may miss tx queue wakeup Sasha Levin
2019-05-22 19:22 ` [PATCH AUTOSEL 4.19 014/244] orangefs: truncate before updating size Sasha Levin
2019-05-22 19:22 ` Sasha Levin [this message]
2019-05-22 19:22 ` [PATCH AUTOSEL 4.19 016/244] pinctrl: zte: fix leaked of_node references Sasha Levin
2019-05-22 19:22 ` [PATCH AUTOSEL 4.19 017/244] ASoC: Intel: kbl_da7219_max98357a: Map BTN_0 to KEY_PLAYPAUSE Sasha Levin
2019-05-22 19:22 ` [PATCH AUTOSEL 4.19 018/244] usb: dwc2: gadget: Increase descriptors count for ISOC's Sasha Levin
2019-05-22 19:22 ` [PATCH AUTOSEL 4.19 019/244] usb: dwc3: move synchronize_irq() out of the spinlock protected block Sasha Levin
2019-05-22 19:22 ` [PATCH AUTOSEL 4.19 020/244] ASoC: hdmi-codec: unlock the device on startup errors Sasha Levin
2019-05-22 19:22 ` [PATCH AUTOSEL 4.19 021/244] leds: avoid races with workqueue Sasha Levin
2019-05-22 19:22 ` [PATCH AUTOSEL 4.19 022/244] powerpc/perf: Return accordingly on invalid chip-id in Sasha Levin
2019-05-22 19:22 ` [PATCH AUTOSEL 4.19 023/244] powerpc/boot: Fix missing check of lseek() return value Sasha Levin
2019-05-22 19:22 ` [PATCH AUTOSEL 4.19 024/244] powerpc/perf: Fix loop exit condition in nest_imc_event_init Sasha Levin
2019-05-22 19:22 ` [PATCH AUTOSEL 4.19 025/244] ASoC: imx: fix fiq dependencies Sasha Levin
2019-05-22 19:22 ` [PATCH AUTOSEL 4.19 026/244] spi: pxa2xx: fix SCR (divisor) calculation Sasha Levin
2019-05-22 19:22 ` [PATCH AUTOSEL 4.19 027/244] brcm80211: potential NULL dereference in brcmf_cfg80211_vndr_cmds_dcmd_handler() Sasha Levin
2019-05-22 19:22 ` [PATCH AUTOSEL 4.19 028/244] ACPI / property: fix handling of data_nodes in acpi_get_next_subnode() Sasha Levin
2019-05-22 19:22 ` [PATCH AUTOSEL 4.19 029/244] drm/nouveau/bar/nv50: ensure BAR is mapped Sasha Levin
2019-05-22 19:22 ` [PATCH AUTOSEL 4.19 030/244] media: stm32-dcmi: return appropriate error codes during probe Sasha Levin
2019-05-22 19:22 ` [PATCH AUTOSEL 4.19 031/244] ARM: vdso: Remove dependency with the arch_timer driver internals Sasha Levin
2019-05-22 19:22 ` [PATCH AUTOSEL 4.19 032/244] arm64: Fix compiler warning from pte_unmap() with -Wunused-but-set-variable Sasha Levin
2019-05-22 19:22 ` [PATCH AUTOSEL 4.19 033/244] powerpc/watchdog: Use hrtimers for per-CPU heartbeat Sasha Levin
2019-05-22 19:23 ` [PATCH AUTOSEL 4.19 034/244] sched/cpufreq: Fix kobject memleak Sasha Levin
2019-05-22 19:23 ` [PATCH AUTOSEL 4.19 035/244] scsi: qla2xxx: Fix a qla24xx_enable_msix() error path Sasha Levin
2019-05-22 19:23 ` [PATCH AUTOSEL 4.19 036/244] scsi: qla2xxx: Fix abort handling in tcm_qla2xxx_write_pending() Sasha Levin
2019-05-22 19:23 ` [PATCH AUTOSEL 4.19 037/244] scsi: qla2xxx: Avoid that lockdep complains about unsafe locking in tcm_qla2xxx_close_session() Sasha Levin
2019-05-22 19:23 ` [PATCH AUTOSEL 4.19 038/244] scsi: qla2xxx: Fix hardirq-unsafe locking Sasha Levin
2019-05-22 19:23 ` [PATCH AUTOSEL 4.19 039/244] x86/modules: Avoid breaking W^X while loading modules Sasha Levin
2019-05-22 19:23 ` [PATCH AUTOSEL 4.19 040/244] Btrfs: fix data bytes_may_use underflow with fallocate due to failed quota reserve Sasha Levin
2019-05-22 19:23 ` [PATCH AUTOSEL 4.19 041/244] btrfs: fix panic during relocation after ENOSPC before writeback happens Sasha Levin
2019-05-22 19:23 ` [PATCH AUTOSEL 4.19 042/244] btrfs: Don't panic when we can't find a root key Sasha Levin
2019-05-22 19:23 ` [PATCH AUTOSEL 4.19 043/244] iwlwifi: pcie: don't crash on invalid RX interrupt Sasha Levin
2019-05-22 19:23 ` [PATCH AUTOSEL 4.19 044/244] rtc: 88pm860x: prevent use-after-free on device remove Sasha Levin
2019-05-22 19:23 ` [PATCH AUTOSEL 4.19 045/244] rtc: stm32: manage the get_irq probe defer case Sasha Levin
2019-05-22 19:23 ` [PATCH AUTOSEL 4.19 046/244] scsi: qedi: Abort ep termination if offload not scheduled Sasha Levin
2019-05-22 19:23 ` [PATCH AUTOSEL 4.19 047/244] s390/kexec_file: Fix detection of text segment in ELF loader Sasha Levin
2019-05-22 19:23 ` [PATCH AUTOSEL 4.19 048/244] sched/nohz: Run NOHZ idle load balancer on HK_FLAG_MISC CPUs Sasha Levin
2019-05-22 19:23 ` [PATCH AUTOSEL 4.19 049/244] w1: fix the resume command API Sasha Levin
2019-05-22 19:23 ` [PATCH AUTOSEL 4.19 050/244] s390: qeth: address type mismatch warning Sasha Levin
2019-05-22 19:23 ` [PATCH AUTOSEL 4.19 051/244] dmaengine: pl330: _stop: clear interrupt status Sasha Levin
2019-05-22 19:23 ` [PATCH AUTOSEL 4.19 052/244] mac80211/cfg80211: update bss channel on channel switch Sasha Levin
2019-05-22 19:23 ` [PATCH AUTOSEL 4.19 053/244] USB: serial: fix initial-termios handling Sasha Levin
2019-05-22 19:23 ` [PATCH AUTOSEL 4.19 054/244] libbpf: fix samples/bpf build failure due to undefined UINT32_MAX Sasha Levin
2019-05-22 19:23 ` [PATCH AUTOSEL 4.19 055/244] slimbus: fix a potential NULL pointer dereference in of_qcom_slim_ngd_register Sasha Levin
2019-05-22 19:23 ` [PATCH AUTOSEL 4.19 056/244] driver core: platform: Fix the usage of platform device name(pdev->name) Sasha Levin
2019-05-22 19:23 ` [PATCH AUTOSEL 4.19 057/244] ASoC: fsl_sai: Update is_slave_mode with correct value Sasha Levin
2019-05-22 19:23 ` [PATCH AUTOSEL 4.19 058/244] mwifiex: prevent an array overflow Sasha Levin
2019-05-22 19:23 ` [PATCH AUTOSEL 4.19 059/244] rsi: Fix NULL pointer dereference in kmalloc Sasha Levin
2019-05-22 19:23 ` [PATCH AUTOSEL 4.19 060/244] net: cw1200: fix a NULL pointer dereference Sasha Levin
2019-05-22 19:23 ` [PATCH AUTOSEL 4.19 061/244] at76c50x-usb: Don't register led_trigger if usb_register_driver failed Sasha Levin
2019-05-22 19:23 ` [PATCH AUTOSEL 4.19 062/244] nvme: set 0 capacity if namespace block size exceeds PAGE_SIZE Sasha Levin
2019-05-22 19:23 ` [PATCH AUTOSEL 4.19 063/244] nvme-rdma: fix a NULL deref when an admin connect times out Sasha Levin
2019-05-22 19:23 ` [PATCH AUTOSEL 4.19 064/244] ssb: Fix possible NULL pointer dereference in ssb_host_pcmcia_exit Sasha Levin
2019-05-22 19:23 ` [PATCH AUTOSEL 4.19 065/244] crypto: sun4i-ss - Fix invalid calculation of hash end Sasha Levin
2019-05-22 19:23 ` [PATCH AUTOSEL 4.19 066/244] bcache: avoid potential memleak of list of journal_replay(s) in the CACHE_SYNC branch of run_cache_set Sasha Levin
2019-05-22 19:23 ` [PATCH AUTOSEL 4.19 067/244] bcache: return error immediately in bch_journal_replay() Sasha Levin
2019-05-22 19:23 ` [PATCH AUTOSEL 4.19 068/244] bcache: fix failure in journal relplay Sasha Levin
2019-05-22 19:23 ` [PATCH AUTOSEL 4.19 069/244] bcache: add failure check to run_cache_set() for journal replay Sasha Levin
2019-05-22 19:23 ` [PATCH AUTOSEL 4.19 070/244] bcache: avoid clang -Wunintialized warning Sasha Levin
2019-05-22 19:23 ` [PATCH AUTOSEL 4.19 071/244] RDMA/cma: Consider scope_id while binding to ipv6 ll address Sasha Levin
2019-05-22 19:23 ` [PATCH AUTOSEL 4.19 072/244] vfio-ccw: Do not call flush_workqueue while holding the spinlock Sasha Levin
2019-05-22 19:23 ` [PATCH AUTOSEL 4.19 073/244] vfio-ccw: Release any channel program when releasing/removing vfio-ccw mdev Sasha Levin
2019-05-22 19:23 ` [PATCH AUTOSEL 4.19 074/244] x86/build: Move _etext to actual end of .text Sasha Levin
2019-05-22 19:23 ` [PATCH AUTOSEL 4.19 075/244] smpboot: Place the __percpu annotation correctly Sasha Levin
2019-05-22 19:23 ` [PATCH AUTOSEL 4.19 076/244] x86/mm: Remove in_nmi() warning from 64-bit implementation of vmalloc_fault() Sasha Levin
2019-05-22 19:23 ` [PATCH AUTOSEL 4.19 077/244] mlxsw: spectrum_router: Prevent ipv6 gateway with v4 route via replace and append Sasha Levin
2019-05-22 19:29   ` David Ahern
2019-05-22 19:23 ` [PATCH AUTOSEL 4.19 078/244] mm/uaccess: Use 'unsigned long' to placate UBSAN warnings on older GCC versions Sasha Levin
2019-05-22 19:23 ` [PATCH AUTOSEL 4.19 079/244] Bluetooth: hci_qca: Give enough time to ROME controller to bootup Sasha Levin
2019-05-22 19:23 ` [PATCH AUTOSEL 4.19 080/244] HID: logitech-hidpp: use RAP instead of FAP to get the protocol version Sasha Levin
2019-05-22 19:23 ` [PATCH AUTOSEL 4.19 081/244] pinctrl: pistachio: fix leaked of_node references Sasha Levin
2019-05-22 19:23 ` [PATCH AUTOSEL 4.19 082/244] pinctrl: samsung: " Sasha Levin
2019-05-22 19:23 ` [PATCH AUTOSEL 4.19 083/244] clk: rockchip: undo several noc and special clocks as critical on rk3288 Sasha Levin

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