x86/kprobes: Fix crash when probing CS CALL instructionsgrafted

When using eBPF to probe CS CALL instructions within a function,
a crash can be triggered.

The eBPF tool probes offset 257 of the __hrtimer_run_queues()
function:

<__hrtimer_run_queues+249>:  nopl   0x0(%rax,%rax,1)
<__hrtimer_run_queues+254>:  mov    %r14,%rdi
<__hrtimer_run_queues+257>:  cs call <__x86_indirect_thunk_r12>
<__hrtimer_run_queues+263>:  mov    %eax,%r12d
<__hrtimer_run_queues+266>:  xchg   %ax,%ax
<__hrtimer_run_queues+268>:  mov    %r13,%rdi

Which triggers this crash:

  BUG: unable to handle page fault for address: 00000000000f41c9
  #PF: supervisor write access in kernel mode
  #PF: error_code(0x0002) - not-present page
  PGD 0 P4D 0
  Oops: 0002 [#1] SMP NOPTI
  CPU: 1 PID: 0 Comm: swapper/1 Kdump: loaded Tainted: P
  RIP: 0010:__hrtimer_run_queues+0x106/0x230

Note that __hrtimer_run_queues+0x106 is __hrtimer_run_queues+262, which is
at the 6th byte of the above CS CALL instruction. Since the CS CALL
instruction occupies 6 bytes, the exception occurred in the middle of that
call instruction.

The root cause is that when using eBPF tools to probe in the middle of a
function, a kprobe with INT3 is used as the underlying implementation.

During single-step emulation of the original CALL instruction,
int3_emulate_call() assumes that the probed CALL instruction is 5 bytes
long. However, the actual CS-prefixed CALL instruction occupies 6 bytes,
so it constructs an incorrect exception return address. When the CPU
returns from the kprobe handler, the next instruction to be executed is at
the address of the last byte of that CS CALL instruction. Coincidentally,
starting from that address, the CPU fetches and decodes a completely
different instruction, which ultimately triggers a kernel crash.

Fix the issue by using the actual instruction length obtained from
the instruction decoder when constructing the exception return
address, rather than relying on the hardcoded CALL_INSN_SIZE macro.

[ mingo: Refined the changelog ]

Fixes: 6256e668b7af ("x86/kprobes: Use int3 instead of debug trap for single-step")
Suggested-by: Masami Hiramatsu (Google) <mhiramat@kernel.org>
Signed-off-by: Jinke Han <jinkehan@didiglobal.com>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Reviewed-by: Masami Hiramatsu (Google) <mhiramat@kernel.org>
Acked-by: Yafang Shao <laoar.shao@gmail.com>
Acked-by: Borislav Petkov <bp@alien8.de>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: https://patch.msgid.link/20260908073742.GA10517@didi-ThinkCentre-M920t-N000

1 files changed, 423 insertions, 0 deletions

diff --git a/sound/soc/qcom/common.c b/sound/soc/qcom/common.c
new file mode 100644
index 000000000..d9f256d51
--- /dev/null
+++ b/sound/soc/qcom/common.c
@@ -0,0 +1,423 @@
+// SPDX-License-Identifier: GPL-2.0
+// Copyright (c) 2018, Linaro Limited.
+// Copyright (c) 2018, The Linux Foundation. All rights reserved.
+
+#include <dt-bindings/sound/qcom,q6afe.h>
+#include <linux/module.h>
+#include <sound/jack.h>
+#include <linux/input-event-codes.h>
+#include "common.h"
+
+#define NAME_SIZE	32
+
+static const struct snd_soc_dapm_widget qcom_jack_snd_widgets[] = {
+	SND_SOC_DAPM_HP("Headphone Jack", NULL),
+	SND_SOC_DAPM_MIC("Mic Jack", NULL),
+	SND_SOC_DAPM_SPK("DP0 Jack", NULL),
+	SND_SOC_DAPM_SPK("DP1 Jack", NULL),
+	SND_SOC_DAPM_SPK("DP2 Jack", NULL),
+	SND_SOC_DAPM_SPK("DP3 Jack", NULL),
+	SND_SOC_DAPM_SPK("DP4 Jack", NULL),
+	SND_SOC_DAPM_SPK("DP5 Jack", NULL),
+	SND_SOC_DAPM_SPK("DP6 Jack", NULL),
+	SND_SOC_DAPM_SPK("DP7 Jack", NULL),
+};
+
+static struct device_node *qcom_snd_get_link_node(struct snd_soc_pcm_runtime *rtd)
+{
+	struct snd_soc_dai *cpu_dai = snd_soc_rtd_to_cpu(rtd, 0);
+	struct snd_soc_card *card = rtd->card;
+	struct of_phandle_args args;
+	int ret;
+
+	if (!card->dev || !card->dev->of_node)
+		return NULL;
+
+	for_each_available_child_of_node_scoped(card->dev->of_node, np) {
+		struct device_node *cpu_np __free(device_node) =
+			of_get_child_by_name(np, "cpu");
+
+		if (!cpu_np)
+			continue;
+
+		ret = of_parse_phandle_with_args(cpu_np, "sound-dai", "#sound-dai-cells", 0,
+						 &args);
+		if (ret)
+			continue;
+
+		if (args.np == rtd->dai_link->cpus[0].of_node &&
+		    args.args_count == 1 && args.args[0] == cpu_dai->id) {
+			of_node_put(args.np);
+			return of_node_get(np);
+		}
+
+		of_node_put(args.np);
+	}
+
+	return NULL;
+}
+
+static int qcom_snd_parse_tdm_slot(struct device_node *np,
+				   struct qcom_snd_tdm_slot_cfg *cfg)
+{
+	memset(cfg, 0, sizeof(*cfg));
+
+	return snd_soc_of_parse_tdm_slot(np, &cfg->tx_mask, &cfg->rx_mask,
+					 &cfg->slots, &cfg->slot_width);
+}
+
+static int qcom_snd_normalize_tdm_slots(struct qcom_snd_tdm_slot_cfg *cpu_cfg,
+					struct qcom_snd_tdm_slot_cfg *codec_cfg)
+{
+	unsigned int slots;
+	unsigned int slot_width;
+
+	if (cpu_cfg->slots && codec_cfg->slots && cpu_cfg->slots != codec_cfg->slots)
+		return -EINVAL;
+
+	if (cpu_cfg->slot_width && codec_cfg->slot_width &&
+	    cpu_cfg->slot_width != codec_cfg->slot_width)
+		return -EINVAL;
+
+	slots = cpu_cfg->slots ?: codec_cfg->slots;
+	if (!slots)
+		return 0;
+
+	slot_width = cpu_cfg->slot_width ?: codec_cfg->slot_width;
+	if (!slot_width)
+		return -EINVAL;
+
+	cpu_cfg->slots = slots;
+	codec_cfg->slots = slots;
+	cpu_cfg->slot_width = slot_width;
+	codec_cfg->slot_width = slot_width;
+
+	return 0;
+}
+
+static int qcom_snd_parse_dai_tdm_slots(struct snd_soc_pcm_runtime *rtd,
+					struct qcom_snd_tdm_slot_cfg *cpu_cfg,
+					struct qcom_snd_tdm_slot_cfg *codec_cfg)
+{
+	struct device_node *link_np __free(device_node) = qcom_snd_get_link_node(rtd);
+	int ret;
+
+	if (!link_np)
+		return -ENOENT;
+
+	struct device_node *cpu_np __free(device_node) =
+		of_get_child_by_name(link_np, "cpu");
+	struct device_node *codec_np __free(device_node) =
+		of_get_child_by_name(link_np, "codec");
+	if (!cpu_np || !codec_np)
+		return -ENOENT;
+
+	ret = qcom_snd_parse_tdm_slot(cpu_np, cpu_cfg);
+	if (ret)
+		return ret;
+
+	return qcom_snd_parse_tdm_slot(codec_np, codec_cfg);
+}
+
+int qcom_snd_get_dai_tdm_slots(struct snd_soc_pcm_runtime *rtd,
+			       struct qcom_snd_tdm_slot_cfg *cpu_cfg,
+			       struct qcom_snd_tdm_slot_cfg *codec_cfg)
+{
+	int ret;
+
+	ret = qcom_snd_parse_dai_tdm_slots(rtd, cpu_cfg, codec_cfg);
+	if (ret)
+		return ret;
+
+	return qcom_snd_normalize_tdm_slots(cpu_cfg, codec_cfg);
+}
+EXPORT_SYMBOL_GPL(qcom_snd_get_dai_tdm_slots);
+
+int qcom_snd_apply_dai_tdm_slots_cfg(struct snd_soc_pcm_runtime *rtd,
+				     const struct qcom_snd_tdm_slot_cfg *cpu_cfg,
+				     const struct qcom_snd_tdm_slot_cfg *codec_cfg)
+{
+	struct snd_soc_dai *cpu_dai = snd_soc_rtd_to_cpu(rtd, 0);
+	struct snd_soc_dai *codec_dai;
+	int i;
+	int ret;
+
+	if (!cpu_cfg->slots)
+		return 0;
+
+	ret = snd_soc_dai_set_tdm_slot(cpu_dai, cpu_cfg->tx_mask, cpu_cfg->rx_mask,
+				       cpu_cfg->slots, cpu_cfg->slot_width);
+	if (ret)
+		return ret;
+
+	for_each_rtd_codec_dais(rtd, i, codec_dai) {
+		ret = snd_soc_dai_set_tdm_slot(codec_dai,
+					       codec_cfg->tx_mask,
+					       codec_cfg->rx_mask,
+					       codec_cfg->slots,
+					       codec_cfg->slot_width);
+		if (ret)
+			return ret;
+	}
+
+	return 0;
+}
+EXPORT_SYMBOL_GPL(qcom_snd_apply_dai_tdm_slots_cfg);
+
+int qcom_snd_apply_dai_tdm_slots(struct snd_soc_pcm_runtime *rtd)
+{
+	struct qcom_snd_tdm_slot_cfg cpu_cfg;
+	struct qcom_snd_tdm_slot_cfg codec_cfg;
+	int ret;
+
+	ret = qcom_snd_get_dai_tdm_slots(rtd, &cpu_cfg, &codec_cfg);
+	if (ret)
+		return ret == -ENOENT ? 0 : ret;
+
+	return qcom_snd_apply_dai_tdm_slots_cfg(rtd, &cpu_cfg, &codec_cfg);
+}
+EXPORT_SYMBOL_GPL(qcom_snd_apply_dai_tdm_slots);
+
+int qcom_snd_parse_of(struct snd_soc_card *card)
+{
+	struct device *dev = card->dev;
+	struct snd_soc_dai_link *link;
+	struct of_phandle_args args;
+	struct snd_soc_dai_link_component *dlc;
+	int ret, num_links;
+
+	ret = snd_soc_of_parse_card_name(card, "model");
+	if (ret == 0 && !card->name)
+		/* Deprecated, only for compatibility with old device trees */
+		ret = snd_soc_of_parse_card_name(card, "qcom,model");
+	if (ret) {
+		dev_err(dev, "Error parsing card name: %d\n", ret);
+		return ret;
+	}
+
+	if (of_property_present(dev->of_node, "widgets")) {
+		ret = snd_soc_of_parse_audio_simple_widgets(card, "widgets");
+		if (ret)
+			return ret;
+	}
+
+	/* DAPM routes */
+	if (of_property_present(dev->of_node, "audio-routing")) {
+		ret = snd_soc_of_parse_audio_routing(card, "audio-routing");
+		if (ret)
+			return ret;
+	}
+	/* Deprecated, only for compatibility with old device trees */
+	if (of_property_present(dev->of_node, "qcom,audio-routing")) {
+		ret = snd_soc_of_parse_audio_routing(card, "qcom,audio-routing");
+		if (ret)
+			return ret;
+	}
+
+	ret = snd_soc_of_parse_pin_switches(card, "pin-switches");
+	if (ret)
+		return ret;
+
+	ret = snd_soc_of_parse_aux_devs(card, "aux-devs");
+	if (ret)
+		return ret;
+
+	/* Populate links */
+	num_links = of_get_available_child_count(dev->of_node);
+
+	/* Allocate the DAI link array */
+	card->dai_link = devm_kcalloc(dev, num_links, sizeof(*link), GFP_KERNEL);
+	if (!card->dai_link)
+		return -ENOMEM;
+
+	card->num_links = num_links;
+	link = card->dai_link;
+
+	for_each_available_child_of_node_scoped(dev->of_node, np) {
+		dlc = devm_kcalloc(dev, 2, sizeof(*dlc), GFP_KERNEL);
+		if (!dlc)
+			return -ENOMEM;
+
+		link->cpus	= &dlc[0];
+		link->platforms	= &dlc[1];
+
+		link->num_cpus		= 1;
+		link->num_platforms	= 1;
+
+		ret = of_property_read_string(np, "link-name", &link->name);
+		if (ret) {
+			dev_err(dev, "error getting codec dai_link name\n");
+			return ret;
+		}
+
+		struct device_node *cpu __free(device_node) =
+			of_get_child_by_name(np, "cpu");
+		struct device_node *platform __free(device_node) =
+			of_get_child_by_name(np, "platform");
+		struct device_node *codec __free(device_node) =
+			of_get_child_by_name(np, "codec");
+
+		if (!cpu) {
+			dev_err(dev, "%s: Can't find cpu DT node\n", link->name);
+			return -EINVAL;
+		}
+
+		ret = snd_soc_of_get_dlc(cpu, &args, link->cpus, 0);
+		if (ret) {
+			dev_err_probe(dev, ret,
+				      "%s: error getting cpu dai name\n", link->name);
+			return ret;
+		}
+
+		link->id = args.args[0];
+
+		if (link->id >= LPASS_MAX_PORT) {
+			dev_err(dev, "%s: Invalid cpu dai id %d\n", link->name, link->id);
+			return -EINVAL;
+		}
+
+		if (platform) {
+			link->platforms->of_node = of_parse_phandle(platform,
+					"sound-dai",
+					0);
+			if (!link->platforms->of_node) {
+				dev_err(dev, "%s: platform dai not found\n", link->name);
+				return -EINVAL;
+			}
+		} else {
+			link->platforms->of_node = link->cpus->of_node;
+		}
+
+		if (codec) {
+			ret = snd_soc_of_get_dai_link_codecs(dev, codec, link);
+			if (ret < 0) {
+				dev_err_probe(dev, ret,
+					      "%s: codec dai not found\n", link->name);
+				return ret;
+			}
+
+			if (platform) {
+				/* DPCM backend */
+				link->no_pcm = 1;
+				link->ignore_pmdown_time = 1;
+			}
+		} else {
+			/* DPCM frontend */
+			link->codecs	 = &snd_soc_dummy_dlc;
+			link->num_codecs = 1;
+			link->dynamic = 1;
+		}
+
+		if (platform || !codec) {
+			/* DPCM */
+			link->ignore_suspend = 1;
+			link->nonatomic = 1;
+		}
+
+		link->stream_name = link->name;
+		link++;
+	}
+
+	if (!card->dapm_widgets) {
+		card->dapm_widgets = qcom_jack_snd_widgets;
+		card->num_dapm_widgets = ARRAY_SIZE(qcom_jack_snd_widgets);
+	}
+
+	return 0;
+}
+EXPORT_SYMBOL_GPL(qcom_snd_parse_of);
+
+static struct snd_soc_jack_pin qcom_headset_jack_pins[] = {
+	/* Headset */
+	{
+		.pin = "Mic Jack",
+		.mask = SND_JACK_MICROPHONE,
+	},
+	{
+		.pin = "Headphone Jack",
+		.mask = SND_JACK_HEADPHONE,
+	},
+};
+
+int qcom_snd_wcd_jack_setup(struct snd_soc_pcm_runtime *rtd,
+			    struct snd_soc_jack *jack, bool *jack_setup)
+{
+	struct snd_soc_dai *cpu_dai = snd_soc_rtd_to_cpu(rtd, 0);
+	struct snd_soc_dai *codec_dai = snd_soc_rtd_to_codec(rtd, 0);
+	struct snd_soc_card *card = rtd->card;
+	int rval, i;
+
+	if (!*jack_setup) {
+		rval = snd_soc_card_jack_new_pins(card, "Headset Jack",
+					     SND_JACK_HEADSET | SND_JACK_LINEOUT |
+					     SND_JACK_MECHANICAL |
+					     SND_JACK_BTN_0 | SND_JACK_BTN_1 |
+					     SND_JACK_BTN_2 | SND_JACK_BTN_3 |
+					     SND_JACK_BTN_4 | SND_JACK_BTN_5,
+					     jack, qcom_headset_jack_pins,
+					     ARRAY_SIZE(qcom_headset_jack_pins));
+
+		if (rval < 0) {
+			dev_err(card->dev, "Unable to add Headphone Jack\n");
+			return rval;
+		}
+
+		snd_jack_set_key(jack->jack, SND_JACK_BTN_0, KEY_MEDIA);
+		snd_jack_set_key(jack->jack, SND_JACK_BTN_1, KEY_VOICECOMMAND);
+		snd_jack_set_key(jack->jack, SND_JACK_BTN_2, KEY_VOLUMEUP);
+		snd_jack_set_key(jack->jack, SND_JACK_BTN_3, KEY_VOLUMEDOWN);
+		*jack_setup = true;
+	}
+
+	switch (cpu_dai->id) {
+	case LPI_MI2S_RX_0:
+	case TX_CODEC_DMA_TX_0:
+	case TX_CODEC_DMA_TX_1:
+	case TX_CODEC_DMA_TX_2:
+	case TX_CODEC_DMA_TX_3:
+		for_each_rtd_codec_dais(rtd, i, codec_dai) {
+			rval = snd_soc_component_set_jack(codec_dai->component,
+							  jack, NULL);
+			if (rval != 0 && rval != -ENOTSUPP) {
+				dev_warn(card->dev, "Failed to set jack: %d\n", rval);
+				return rval;
+			}
+		}
+
+		break;
+	default:
+		break;
+	}
+
+
+	return 0;
+}
+EXPORT_SYMBOL_GPL(qcom_snd_wcd_jack_setup);
+
+int qcom_snd_dp_jack_setup(struct snd_soc_pcm_runtime *rtd,
+			   struct snd_soc_jack *dp_jack, int dp_pcm_id)
+{
+	struct snd_soc_dai *codec_dai = snd_soc_rtd_to_codec(rtd, 0);
+	struct snd_soc_card *card = rtd->card;
+	char jack_name[NAME_SIZE];
+	int rval, i;
+
+	snprintf(jack_name, sizeof(jack_name), "DP%d Jack", dp_pcm_id);
+	rval = snd_soc_card_jack_new(card, jack_name, SND_JACK_AVOUT, dp_jack);
+	if (rval)
+		return rval;
+
+	for_each_rtd_codec_dais(rtd, i, codec_dai) {
+		rval = snd_soc_component_set_jack(codec_dai->component, dp_jack, NULL);
+		if (rval != 0 && rval != -ENOTSUPP) {
+			dev_warn(card->dev, "Failed to set jack: %d\n", rval);
+			return rval;
+		}
+	}
+
+	return 0;
+}
+EXPORT_SYMBOL_GPL(qcom_snd_dp_jack_setup);
+
+MODULE_DESCRIPTION("ASoC Qualcomm helper functions");
+MODULE_LICENSE("GPL");