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, 131 insertions, 0 deletions

diff --git a/drivers/clk/imx/Kconfig b/drivers/clk/imx/Kconfig
new file mode 100644
index 000000000..b292e7ca5
--- /dev/null
+++ b/drivers/clk/imx/Kconfig
@@ -0,0 +1,131 @@
+# SPDX-License-Identifier: GPL-2.0
+# common clock support for NXP i.MX SoC family.
+config MXC_CLK
+	tristate "IMX clock"
+	depends on ARCH_MXC || COMPILE_TEST
+
+config MXC_CLK_SCU
+	tristate
+
+config CLK_IMX1
+	def_bool SOC_IMX1
+	select MXC_CLK
+
+config CLK_IMX25
+	def_bool SOC_IMX25
+	select MXC_CLK
+
+config CLK_IMX27
+	def_bool SOC_IMX27
+	select MXC_CLK
+
+config CLK_IMX31
+	def_bool SOC_IMX31
+	select MXC_CLK
+
+config CLK_IMX35
+	def_bool SOC_IMX35
+	select MXC_CLK
+
+config CLK_IMX5
+	def_bool SOC_IMX5
+	select MXC_CLK
+
+config CLK_IMX6Q
+	def_bool SOC_IMX6Q
+	select MXC_CLK
+
+config CLK_IMX6SL
+	def_bool SOC_IMX6SL
+	select MXC_CLK
+
+config CLK_IMX6SLL
+	def_bool SOC_IMX6SLL
+	select MXC_CLK
+
+config CLK_IMX6SX
+	def_bool SOC_IMX6SX
+	select MXC_CLK
+
+config CLK_IMX6UL
+	def_bool SOC_IMX6UL
+	select MXC_CLK
+
+config CLK_IMX7D
+	def_bool SOC_IMX7D
+	select MXC_CLK
+
+config CLK_IMX7ULP
+	def_bool SOC_IMX7ULP
+	select MXC_CLK
+
+config CLK_VF610
+	def_bool SOC_VF610
+	select MXC_CLK
+
+config CLK_IMX8MM
+	tristate "IMX8MM CCM Clock Driver"
+	depends on ARCH_MXC || COMPILE_TEST
+	select MXC_CLK
+	help
+	    Build the driver for i.MX8MM CCM Clock Driver
+
+config CLK_IMX8MN
+	tristate "IMX8MN CCM Clock Driver"
+	depends on ARCH_MXC || COMPILE_TEST
+	select MXC_CLK
+	help
+	    Build the driver for i.MX8MN CCM Clock Driver
+
+config CLK_IMX8MP
+	tristate "IMX8MP CCM Clock Driver"
+	depends on ARCH_MXC || COMPILE_TEST
+	select MXC_CLK
+	select AUXILIARY_BUS if RESET_CONTROLLER
+	help
+	    Build the driver for i.MX8MP CCM Clock Driver
+
+config CLK_IMX8MQ
+	tristate "IMX8MQ CCM Clock Driver"
+	depends on ARCH_MXC || COMPILE_TEST
+	select MXC_CLK
+	help
+	    Build the driver for i.MX8MQ CCM Clock Driver
+
+config CLK_IMX8QXP
+	tristate "IMX8QXP SCU Clock"
+	depends on (ARCH_MXC && ARM64) || COMPILE_TEST
+	depends on IMX_SCU && HAVE_ARM_SMCCC
+	select MXC_CLK_SCU
+	select MXC_CLK
+	help
+	  Build the driver for IMX8QXP SCU based clocks.
+
+config CLK_IMX8ULP
+	tristate "IMX8ULP CCM Clock Driver"
+	depends on ARCH_MXC || COMPILE_TEST
+	select MXC_CLK
+	select AUXILIARY_BUS
+	help
+	    Build the driver for i.MX8ULP CCM Clock Driver
+
+config CLK_IMX93
+	tristate "IMX93 CCM Clock Driver"
+	depends on ARCH_MXC || COMPILE_TEST
+	select MXC_CLK
+	help
+	    Build the driver for i.MX93 CCM Clock Driver
+
+config CLK_IMX95_BLK_CTL
+	tristate "IMX95 Clock Driver for BLK CTL"
+	depends on ARCH_MXC || COMPILE_TEST
+	select MXC_CLK
+	help
+	    Build the clock driver for i.MX95 BLK CTL
+
+config CLK_IMXRT1050
+	tristate "IMXRT1050 CCM Clock Driver"
+	depends on SOC_IMXRT || COMPILE_TEST
+	select MXC_CLK
+	help
+	    Build the driver for i.MXRT1050 CCM Clock Driver