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, 55 insertions, 0 deletions

diff --git a/drivers/soc/fsl/Kconfig b/drivers/soc/fsl/Kconfig
new file mode 100644
index 000000000..47870e29c
--- /dev/null
+++ b/drivers/soc/fsl/Kconfig
@@ -0,0 +1,55 @@
+# SPDX-License-Identifier: GPL-2.0-only
+#
+# NXP/Freescale QorIQ series SOC drivers
+#
+
+menu "NXP/Freescale QorIQ SoC drivers"
+
+source "drivers/soc/fsl/qbman/Kconfig"
+source "drivers/soc/fsl/qe/Kconfig"
+
+config FSL_GUTS
+	bool
+	select SOC_BUS
+	help
+	  The global utilities block controls power management, I/O device
+	  enabling, power-onreset(POR) configuration monitoring, alternate
+	  function selection for multiplexed signals,and clock control.
+	  This driver is to manage and access global utilities block.
+	  Initially only reading SVR and registering soc device are supported.
+	  Other guts accesses, such as reading RCW, should eventually be moved
+	  into this driver as well.
+
+config FSL_MC_DPIO
+        tristate "QorIQ DPAA2 DPIO driver"
+        depends on FSL_MC_BUS && NET
+        select SOC_BUS
+        select FSL_GUTS
+        select DIMLIB
+        help
+	  Driver for the DPAA2 DPIO object.  A DPIO provides queue and
+	  buffer management facilities for software to interact with
+	  other DPAA2 objects. This driver does not expose the DPIO
+	  objects individually, but groups them under a service layer
+	  API.
+
+config DPAA2_CONSOLE
+	tristate "QorIQ DPAA2 console driver"
+	depends on OF && (ARCH_LAYERSCAPE || COMPILE_TEST)
+	default ARCH_LAYERSCAPE
+	help
+	  Console driver for DPAA2 platforms. Exports 2 char devices,
+	  /dev/dpaa2_mc_console and /dev/dpaa2_aiop_console,
+	  which can be used to dump the Management Complex and AIOP
+	  firmware logs.
+
+config FSL_RCPM
+	bool "Freescale RCPM support"
+	depends on PM_SLEEP && (ARM || ARM64)
+	help
+	  The NXP QorIQ Processors based on ARM Core have RCPM module
+	  (Run Control and Power Management), which performs all device-level
+	  tasks associated with power management, such as wakeup source control.
+	  Note that currently this driver will not support PowerPC based
+	  QorIQ processor.
+endmenu