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, 158 insertions, 0 deletions

diff --git a/include/sound/sof/control.h b/include/sound/sof/control.h
new file mode 100644
index 000000000..8d3300dd9
--- /dev/null
+++ b/include/sound/sof/control.h
@@ -0,0 +1,158 @@
+/* SPDX-License-Identifier: (GPL-2.0-only OR BSD-3-Clause) */
+/*
+ * This file is provided under a dual BSD/GPLv2 license.  When using or
+ * redistributing this file, you may do so under either license.
+ *
+ * Copyright(c) 2018 Intel Corporation
+ */
+
+#ifndef __INCLUDE_SOUND_SOF_CONTROL_H__
+#define __INCLUDE_SOUND_SOF_CONTROL_H__
+
+#include <uapi/sound/sof/header.h>
+#include <sound/sof/header.h>
+
+/*
+ * Component Mixers and Controls
+ */
+
+/* channel positions - uses same values as ALSA */
+enum sof_ipc_chmap {
+	SOF_CHMAP_UNKNOWN = 0,
+	SOF_CHMAP_NA,		/**< N/A, silent */
+	SOF_CHMAP_MONO,		/**< mono stream */
+	SOF_CHMAP_FL,		/**< front left */
+	SOF_CHMAP_FR,		/**< front right */
+	SOF_CHMAP_RL,		/**< rear left */
+	SOF_CHMAP_RR,		/**< rear right */
+	SOF_CHMAP_FC,		/**< front centre */
+	SOF_CHMAP_LFE,		/**< LFE */
+	SOF_CHMAP_SL,		/**< side left */
+	SOF_CHMAP_SR,		/**< side right */
+	SOF_CHMAP_RC,		/**< rear centre */
+	SOF_CHMAP_FLC,		/**< front left centre */
+	SOF_CHMAP_FRC,		/**< front right centre */
+	SOF_CHMAP_RLC,		/**< rear left centre */
+	SOF_CHMAP_RRC,		/**< rear right centre */
+	SOF_CHMAP_FLW,		/**< front left wide */
+	SOF_CHMAP_FRW,		/**< front right wide */
+	SOF_CHMAP_FLH,		/**< front left high */
+	SOF_CHMAP_FCH,		/**< front centre high */
+	SOF_CHMAP_FRH,		/**< front right high */
+	SOF_CHMAP_TC,		/**< top centre */
+	SOF_CHMAP_TFL,		/**< top front left */
+	SOF_CHMAP_TFR,		/**< top front right */
+	SOF_CHMAP_TFC,		/**< top front centre */
+	SOF_CHMAP_TRL,		/**< top rear left */
+	SOF_CHMAP_TRR,		/**< top rear right */
+	SOF_CHMAP_TRC,		/**< top rear centre */
+	SOF_CHMAP_TFLC,		/**< top front left centre */
+	SOF_CHMAP_TFRC,		/**< top front right centre */
+	SOF_CHMAP_TSL,		/**< top side left */
+	SOF_CHMAP_TSR,		/**< top side right */
+	SOF_CHMAP_LLFE,		/**< left LFE */
+	SOF_CHMAP_RLFE,		/**< right LFE */
+	SOF_CHMAP_BC,		/**< bottom centre */
+	SOF_CHMAP_BLC,		/**< bottom left centre */
+	SOF_CHMAP_BRC,		/**< bottom right centre */
+	SOF_CHMAP_LAST = SOF_CHMAP_BRC,
+};
+
+/* control data type and direction */
+enum sof_ipc_ctrl_type {
+	/*  per channel data - uses struct sof_ipc_ctrl_value_chan */
+	SOF_CTRL_TYPE_VALUE_CHAN_GET = 0,
+	SOF_CTRL_TYPE_VALUE_CHAN_SET,
+	/* component data - uses struct sof_ipc_ctrl_value_comp */
+	SOF_CTRL_TYPE_VALUE_COMP_GET,
+	SOF_CTRL_TYPE_VALUE_COMP_SET,
+	/* bespoke data - uses struct sof_abi_hdr */
+	SOF_CTRL_TYPE_DATA_GET,
+	SOF_CTRL_TYPE_DATA_SET,
+};
+
+/* control command type */
+enum sof_ipc_ctrl_cmd {
+	SOF_CTRL_CMD_VOLUME = 0, /**< maps to ALSA volume style controls */
+	SOF_CTRL_CMD_ENUM,	/**< maps to ALSA enum style controls */
+	SOF_CTRL_CMD_SWITCH,	/**< maps to ALSA switch style controls */
+	SOF_CTRL_CMD_BINARY,	/**< maps to ALSA binary style controls */
+};
+
+/* generic channel mapped value data */
+struct sof_ipc_ctrl_value_chan {
+	uint32_t channel;	/**< channel map - enum sof_ipc_chmap */
+	uint32_t value;
+} __packed;
+
+/* generic component mapped value data */
+struct sof_ipc_ctrl_value_comp {
+	uint32_t index;	/**< component source/sink/control index in control */
+	union {
+		uint32_t uvalue;
+		int32_t svalue;
+	};
+} __packed;
+
+/* generic control data */
+struct sof_ipc_ctrl_data {
+	struct sof_ipc_reply rhdr;
+	uint32_t comp_id;
+
+	/* control access and data type */
+	uint32_t type;		/**< enum sof_ipc_ctrl_type */
+	uint32_t cmd;		/**< enum sof_ipc_ctrl_cmd */
+	uint32_t index;		/**< control index for comps > 1 control */
+
+	/* control data - can either be appended or DMAed from host */
+	struct sof_ipc_host_buffer buffer;
+	uint32_t num_elems;	/**< in array elems or bytes for data type */
+	uint32_t elems_remaining;	/**< elems remaining if sent in parts */
+
+	uint32_t msg_index;	/**< for large messages sent in parts */
+
+	/* reserved for future use */
+	uint32_t reserved[6];
+
+	/* control data - add new types if needed */
+	union {
+		/* channel values can be used by volume type controls */
+		DECLARE_FLEX_ARRAY(struct sof_ipc_ctrl_value_chan, chanv);
+		/* component values used by routing controls like mux, mixer */
+		DECLARE_FLEX_ARRAY(struct sof_ipc_ctrl_value_comp, compv);
+		/* data can be used by binary controls */
+		DECLARE_FLEX_ARRAY(struct sof_abi_hdr, data);
+	};
+} __packed;
+
+/** Event type */
+enum sof_ipc_ctrl_event_type {
+	SOF_CTRL_EVENT_GENERIC = 0,	/**< generic event */
+	SOF_CTRL_EVENT_GENERIC_METADATA,	/**< generic event with metadata */
+	SOF_CTRL_EVENT_KD,	/**< keyword detection event */
+	SOF_CTRL_EVENT_VAD,	/**< voice activity detection event */
+};
+
+/**
+ * Generic notification data.
+ */
+struct sof_ipc_comp_event {
+	struct sof_ipc_reply rhdr;
+	uint16_t src_comp_type;	/**< COMP_TYPE_ */
+	uint32_t src_comp_id;	/**< source component id */
+	uint32_t event_type;	/**< event type - SOF_CTRL_EVENT_* */
+	uint32_t num_elems;	/**< in array elems or bytes for data type */
+
+	/* reserved for future use */
+	uint32_t reserved[8];
+
+	/* control data - add new types if needed */
+	union {
+		/* data can be used by binary controls */
+		struct sof_abi_hdr data[0];
+		/* event specific values */
+		uint32_t event_value;
+	};
+} __packed;
+
+#endif