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, 257 insertions, 0 deletions

diff --git a/drivers/char/tpm/Kconfig b/drivers/char/tpm/Kconfig
new file mode 100644
index 000000000..5f672f2c0
--- /dev/null
+++ b/drivers/char/tpm/Kconfig
@@ -0,0 +1,257 @@
+# SPDX-License-Identifier: GPL-2.0-only
+#
+# TPM device configuration
+#
+
+menuconfig TCG_TPM
+	tristate "TPM Hardware Support"
+	depends on HAS_IOMEM
+	imply SECURITYFS
+	select CRYPTO
+	select CRYPTO_HASH_INFO
+	help
+	  If you have a TPM security chip in your system, which
+	  implements the Trusted Computing Group's specification,
+	  say Yes and it will be accessible from within Linux.  For
+	  more information see <http://www.trustedcomputinggroup.org>. 
+	  An implementation of the Trusted Software Stack (TSS), the 
+	  userspace enablement piece of the specification, can be 
+	  obtained at: <http://sourceforge.net/projects/trousers>.  To 
+	  compile this driver as a module, choose M here; the module 
+	  will be called tpm. If unsure, say N.
+	  Notes:
+	  1) For more TPM drivers enable CONFIG_PNP, CONFIG_ACPI
+	  and CONFIG_PNPACPI.
+	  2) Without ACPI enabled, the BIOS event log won't be accessible,
+	  which is required to validate the PCR 0-7 values.
+
+if TCG_TPM
+
+config TCG_TPM2_HMAC
+	bool "Use HMAC and encrypted transactions on the TPM bus"
+	default n
+	select CRYPTO_ECDH
+	select CRYPTO_LIB_AESCFB
+	select CRYPTO_LIB_SHA256
+	select CRYPTO_LIB_UTILS
+	help
+	  Setting this causes us to deploy a scheme which uses request
+	  and response HMACs in addition to encryption for
+	  communicating with the TPM to prevent or detect bus snooping
+	  and interposer attacks (see tpm-security.rst).  Saying Y
+	  here adds some encryption overhead to all kernel to TPM
+	  transactions.
+
+config HW_RANDOM_TPM
+	bool "TPM HW Random Number Generator support"
+	depends on TCG_TPM && HW_RANDOM && !(TCG_TPM=y && HW_RANDOM=m)
+	default y
+	help
+	  This setting exposes the TPM's Random Number Generator as a hwrng
+	  device. This allows the kernel to collect randomness from the TPM at
+	  boot, and provides the TPM randomines in /dev/hwrng.
+
+	  If unsure, say Y.
+
+config TCG_TIS_CORE
+	tristate
+	help
+	TCG TIS TPM core driver. It implements the TPM TCG TIS logic and hooks
+	into the TPM kernel APIs. Physical layers will register against it.
+
+config TCG_TIS
+	tristate "TPM Interface Specification 1.2 Interface / TPM 2.0 FIFO Interface"
+	depends on X86 || OF
+	select TCG_TIS_CORE
+	help
+	  If you have a TPM security chip that is compliant with the
+	  TCG TIS 1.2 TPM specification (TPM1.2) or the TCG PTP FIFO
+	  specification (TPM2.0) say Yes and it will be accessible from
+	  within Linux. To compile this driver as a module, choose  M here;
+	  the module will be called tpm_tis.
+
+config TCG_TIS_SPI
+	tristate "TPM Interface Specification 1.3 Interface / TPM 2.0 FIFO Interface - (SPI)"
+	depends on SPI
+	select TCG_TIS_CORE
+	help
+	  If you have a TPM security chip which is connected to a regular,
+	  non-tcg SPI master (i.e. most embedded platforms) that is compliant with the
+	  TCG TIS 1.3 TPM specification (TPM1.2) or the TCG PTP FIFO
+	  specification (TPM2.0) say Yes and it will be accessible from
+	  within Linux. To compile this driver as a module, choose  M here;
+	  the module will be called tpm_tis_spi.
+
+config TCG_TIS_SPI_CR50
+	bool "Cr50 SPI Interface"
+	depends on TCG_TIS_SPI
+	help
+	  If you have a H1 secure module running Cr50 firmware on SPI bus,
+	  say Yes and it will be accessible from within Linux.
+
+config TCG_TIS_I2C
+	tristate "TPM Interface Specification 1.3 Interface / TPM 2.0 FIFO Interface - (I2C - generic)"
+	depends on I2C
+	select CRC_CCITT
+	select TCG_TIS_CORE
+	help
+	  If you have a TPM security chip, compliant with the TCG TPM PTP
+	  (I2C interface) specification and connected to an I2C bus master,
+	  say Yes and it will be accessible from within Linux.
+	  To compile this driver as a module, choose M here;
+	  the module will be called tpm_tis_i2c.
+
+config TCG_TIS_SYNQUACER
+	tristate "TPM Interface Specification 1.2 Interface / TPM 2.0 FIFO Interface (MMIO - SynQuacer)"
+	depends on ARCH_SYNQUACER || COMPILE_TEST
+	select TCG_TIS_CORE
+	help
+	  If you have a TPM security chip that is compliant with the
+	  TCG TIS 1.2 TPM specification (TPM1.2) or the TCG PTP FIFO
+	  specification (TPM2.0) say Yes and it will be accessible from
+	  within Linux on Socionext SynQuacer platform.
+	  To compile this driver as a module, choose  M here;
+	  the module will be called tpm_tis_synquacer.
+
+config TCG_TIS_I2C_CR50
+	tristate "TPM Interface Specification 2.0 Interface (I2C - CR50)"
+	depends on I2C
+	help
+	  This is a driver for the Google cr50 I2C TPM interface which is a
+	  custom microcontroller and requires a custom i2c protocol interface
+	  to handle the limitations of the hardware.  To compile this driver
+	  as a module, choose M here; the module will be called tcg_tis_i2c_cr50.
+
+config TCG_TIS_I2C_ATMEL
+	tristate "TPM Interface Specification 1.2 Interface (I2C - Atmel)"
+	depends on I2C
+	help
+	  If you have an Atmel I2C TPM security chip say Yes and it will be
+	  accessible from within Linux.
+	  To compile this driver as a module, choose M here; the module will
+	  be called tpm_tis_i2c_atmel.
+
+config TCG_TIS_I2C_INFINEON
+	tristate "TPM Interface Specification 1.2 Interface (I2C - Infineon)"
+	depends on I2C
+	help
+	  If you have a TPM security chip that is compliant with the
+	  TCG TIS 1.2 TPM specification and Infineon's I2C Protocol Stack
+	  Specification 0.20 say Yes and it will be accessible from within
+	  Linux.
+	  To compile this driver as a module, choose M here; the module
+	  will be called tpm_i2c_infineon.
+
+config TCG_TIS_I2C_NUVOTON
+	tristate "TPM Interface Specification 1.2 Interface (I2C - Nuvoton)"
+	depends on I2C
+	help
+	  If you have a TPM security chip with an I2C interface from
+	  Nuvoton Technology Corp. say Yes and it will be accessible
+	  from within Linux.
+	  To compile this driver as a module, choose M here; the module
+	  will be called tpm_i2c_nuvoton.
+
+config TCG_NSC
+	tristate "National Semiconductor TPM Interface"
+	depends on X86
+	help
+	  If you have a TPM security chip from National Semiconductor 
+	  say Yes and it will be accessible from within Linux.  To 
+	  compile this driver as a module, choose M here; the module 
+	  will be called tpm_nsc.
+
+config TCG_ATMEL
+	tristate "Atmel TPM Interface"
+	depends on X86
+	help
+	  If you have a TPM security chip from Atmel say Yes and it 
+	  will be accessible from within Linux.  To compile this driver 
+	  as a module, choose M here; the module will be called tpm_atmel.
+
+config TCG_INFINEON
+	tristate "Infineon Technologies TPM Interface"
+	depends on PNP || COMPILE_TEST
+	help
+	  If you have a TPM security chip from Infineon Technologies
+	  (either SLD 9630 TT 1.1 or SLB 9635 TT 1.2) say Yes and it
+	  will be accessible from within Linux.
+	  To compile this driver as a module, choose M here; the module
+	  will be called tpm_infineon.
+	  Further information on this driver and the supported hardware
+	  can be found at http://www.trust.rub.de/projects/linux-device-driver-infineon-tpm/ 
+
+config TCG_IBMVTPM
+	tristate "IBM VTPM Interface"
+	depends on PPC_PSERIES
+	help
+	  If you have IBM virtual TPM (VTPM) support say Yes and it
+	  will be accessible from within Linux.  To compile this driver
+	  as a module, choose M here; the module will be called tpm_ibmvtpm.
+
+config TCG_LOONGSON
+	tristate "Loongson TPM Interface"
+	depends on MFD_LOONGSON_SE
+	help
+	  If you want to make Loongson TPM support available, say Yes and
+	  it will be accessible from within Linux. To compile this
+	  driver as a module, choose M here; the module will be called
+	  tpm_loongson.
+
+config TCG_XEN
+	tristate "XEN TPM Interface"
+	depends on TCG_TPM && XEN
+	select XEN_XENBUS_FRONTEND
+	help
+	  If you want to make TPM support available to a Xen user domain,
+	  say Yes and it will be accessible from within Linux. See
+	  the manpages for xl, xl.conf, and docs/misc/vtpm.txt in
+	  the Xen source repository for more details.
+	  To compile this driver as a module, choose M here; the module
+	  will be called xen-tpmfront.
+
+config TCG_CRB
+	tristate "TPM 2.0 CRB Interface"
+	depends on ACPI
+	help
+	  If you have a TPM security chip that is compliant with the
+	  TCG CRB 2.0 TPM specification say Yes and it will be accessible
+	  from within Linux.  To compile this driver as a module, choose
+	  M here; the module will be called tpm_crb.
+
+config TCG_ARM_CRB_FFA
+	tristate "TPM CRB over Arm FF-A Transport"
+	depends on ARM_FFA_TRANSPORT && TCG_CRB
+	default TCG_CRB
+	help
+	  If the Arm FF-A transport is used to access the TPM say Yes.
+	  To compile this driver as a module, choose M here; the module
+	  will be called tpm_crb_ffa.
+
+config TCG_VTPM_PROXY
+	tristate "VTPM Proxy Interface"
+	depends on TCG_TPM
+	help
+	  This driver proxies for an emulated TPM (vTPM) running in userspace.
+	  A device /dev/vtpmx is provided that creates a device pair
+	  /dev/vtpmX and a server-side file descriptor on which the vTPM
+	  can receive commands.
+
+config TCG_FTPM_TEE
+	tristate "TEE based fTPM Interface"
+	depends on TEE && OPTEE
+	help
+	  This driver proxies for firmware TPM running in TEE.
+
+config TCG_SVSM
+	tristate "SNP SVSM vTPM interface"
+	depends on AMD_MEM_ENCRYPT
+	help
+	  This is a driver for the AMD SVSM vTPM protocol that a SEV-SNP guest
+	  OS can use to discover and talk to a vTPM emulated by the Secure VM
+	  Service Module (SVSM) in the guest context, but at a more privileged
+	  level (usually VMPL0).  To compile this driver as a module, choose M
+	  here; the module will be called tpm_svsm.
+
+source "drivers/char/tpm/st33zp24/Kconfig"
+endif # TCG_TPM