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, 58 insertions, 0 deletions

diff --git a/sound/soc/codecs/rt5575.h b/sound/soc/codecs/rt5575.h
new file mode 100644
index 000000000..752a3c8f5
--- /dev/null
+++ b/sound/soc/codecs/rt5575.h
@@ -0,0 +1,58 @@
+/* SPDX-License-Identifier: GPL-2.0-only */
+/*
+ * rt5575.h  --  ALC5575 ALSA SoC audio driver
+ *
+ * Copyright(c) 2025 Realtek Semiconductor Corp.
+ *
+ */
+
+#ifndef __RT5575_H__
+#define __RT5575_H__
+
+#define RT5575_DEVICE_ID	0x10ec5575
+#define RT5575_DSP_MAPPING	0x18000000
+
+#define RT5575_BOOT		0x8004
+#define RT5575_ID		0x8008
+#define RT5575_ID_1		0x800c
+#define RT5575_MIXL_VOL		0x8a14
+#define RT5575_MIXR_VOL		0x8a18
+#define RT5575_PROMPT_VOL	0x8a84
+#define RT5575_SPK01_VOL	0x8a88
+#define RT5575_SPK23_VOL	0x8a8c
+#define RT5575_MIC1_VOL		0x8a98
+#define RT5575_MIC2_VOL		0x8a9c
+#define RT5575_WNC_CTRL		0x80ec
+#define RT5575_MODE_CTRL	0x80f0
+#define RT5575_I2S_RATE_CTRL	0x80f4
+#define RT5575_SLEEP_CTRL	0x80f8
+#define RT5575_ALG_BYPASS_CTRL	0x80fc
+#define RT5575_PINMUX_CTRL_2	0x81a4
+#define RT5575_GPIO_CTRL_1	0x8208
+#define RT5575_DSP_BUS_CTRL	0x880c
+#define RT5575_SW_INT		0x0018
+#define RT5575_DSP_BOOT_ERR	0x8e14
+#define RT5575_DSP_READY	0x8e24
+#define RT5575_DSP_CMD_ADDR	0x8e28
+#define RT5575_EFUSE_DATA_2	0xc638
+#define RT5575_EFUSE_DATA_3	0xc63c
+#define RT5575_EFUSE_PID	0xc660
+
+#define RT5575_BOOT_MASK	0x3
+#define RT5575_BOOT_SPI		0x0
+
+enum {
+	RT5575_AIF1,
+	RT5575_AIF2,
+	RT5575_AIF3,
+	RT5575_AIF4,
+	RT5575_AIFS,
+};
+
+struct rt5575_priv {
+	struct i2c_client *i2c;
+	struct snd_soc_component *component;
+	struct regmap *dsp_regmap, *regmap;
+};
+
+#endif /* __RT5575_H__ */