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, 127 insertions, 0 deletions

diff --git a/drivers/iio/frequency/Kconfig b/drivers/iio/frequency/Kconfig
new file mode 100644
index 000000000..90c6304c4
--- /dev/null
+++ b/drivers/iio/frequency/Kconfig
@@ -0,0 +1,127 @@
+# SPDX-License-Identifier: GPL-2.0-only
+#
+# Frequency
+#	Direct Digital Synthesis drivers (DDS)
+#	Clock Distribution device drivers
+#	Phase-Locked Loop (PLL) frequency synthesizers
+#
+# When adding new entries keep the list in alphabetical order
+
+menu "Frequency Synthesizers DDS/PLL"
+
+menu "Clock Generator/Distribution"
+
+config AD9523
+	tristate "Analog Devices AD9523 Low Jitter Clock Generator"
+	depends on SPI
+	help
+	  Say yes here to build support for Analog Devices AD9523 Low Jitter
+	  Clock Generator. The driver provides direct access via sysfs.
+
+	  To compile this driver as a module, choose M here: the
+	  module will be called ad9523.
+
+endmenu
+
+#
+# Phase-Locked Loop (PLL) frequency synthesizers
+#
+
+menu "Phase-Locked Loop (PLL) frequency synthesizers"
+
+config ADF41513
+	tristate "Analog Devices ADF41513 PLL Frequency Synthesizer"
+	depends on SPI
+	help
+	  Say yes here to build support for Analog Devices ADF41513
+	  26.5 GHz Integer-N/Fractional-N PLL Frequency Synthesizer.
+
+	  To compile this driver as a module, choose M here: the
+	  module will be called adf41513.
+
+config ADF4350
+	tristate "Analog Devices ADF4350/ADF4351 Wideband Synthesizers"
+	depends on SPI
+	help
+	  Say yes here to build support for Analog Devices  ADF4350/ADF4351
+	  Wideband Synthesizers. The driver provides direct access via sysfs.
+
+	  To compile this driver as a module, choose M here: the
+	  module will be called adf4350.
+
+config ADF4371
+	tristate "Analog Devices ADF4371/ADF4372 Wideband Synthesizers"
+	depends on SPI
+	select REGMAP_SPI
+	help
+	  Say yes here to build support for Analog Devices ADF4371 and ADF4372
+	  Wideband Synthesizers. The driver provides direct access via sysfs.
+
+	  To compile this driver as a module, choose M here: the
+	  module will be called adf4371.
+
+config ADF4377
+	tristate "Analog Devices ADF4377 Microwave Wideband Synthesizer"
+	depends on SPI && COMMON_CLK
+	select REGMAP_SPI
+	help
+	  Say yes here to build support for Analog Devices ADF4377 Microwave
+	  Wideband Synthesizer.
+
+	  To compile this driver as a module, choose M here: the
+	  module will be called adf4377.
+
+config ADMFM2000
+	tristate "Analog Devices ADMFM2000 Dual Microwave Down Converter"
+	depends on GPIOLIB
+	help
+	  Say yes here to build support for Analog Devices ADMFM2000 Dual
+	  Microwave Down Converter.
+
+	  To compile this driver as a module, choose M here: the
+	  module will be called admfm2000.
+
+config ADMV1013
+	tristate "Analog Devices ADMV1013 Microwave Upconverter"
+	depends on SPI && COMMON_CLK
+	help
+	  Say yes here to build support for Analog Devices ADMV1013
+	  24 GHz to 44 GHz, Wideband, Microwave Upconverter.
+
+	  To compile this driver as a module, choose M here: the
+	  module will be called admv1013.
+
+config ADMV1014
+	tristate "Analog Devices ADMV1014 Microwave Downconverter"
+	depends on SPI && COMMON_CLK && 64BIT
+	help
+	  Say yes here to build support for Analog Devices ADMV1014
+	  24 GHz to 44 GHz, Wideband, Microwave Downconverter.
+
+	  To compile this driver as a module, choose M here: the
+	  module will be called admv1014.
+
+config ADMV4420
+	tristate "Analog Devices ADMV4420 K Band Downconverter"
+	depends on SPI
+	select REGMAP_SPI
+	help
+	  Say yes here to build support for Analog Devices K Band
+	  Downconverter with integrated Fractional-N PLL and VCO.
+
+	  To compile this driver as a module, choose M here: the
+	  module will be called admv4420.
+
+config ADRF6780
+	tristate "Analog Devices ADRF6780 Microwave Upconverter"
+	depends on SPI
+	depends on COMMON_CLK
+	help
+	  Say yes here to build support for Analog Devices ADRF6780
+	  5.9 GHz to 23.6 GHz, Wideband, Microwave Upconverter.
+
+	  To compile this driver as a module, choose M here: the
+	  module will be called adrf6780.
+
+endmenu
+endmenu