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/crypto/marvell/Kconfig b/drivers/crypto/marvell/Kconfig
new file mode 100644
index 000000000..aa269abb0
--- /dev/null
+++ b/drivers/crypto/marvell/Kconfig
@@ -0,0 +1,55 @@
+#
+# Marvell crypto drivers configuration
+#
+
+config CRYPTO_DEV_MARVELL
+	tristate
+
+config CRYPTO_DEV_MARVELL_CESA
+	tristate "Marvell's Cryptographic Engine driver"
+	depends on PLAT_ORION || ARCH_MVEBU || COMPILE_TEST
+	select CRYPTO_LIB_AES
+	select CRYPTO_LIB_DES
+	select CRYPTO_SKCIPHER
+	select CRYPTO_HASH
+	select SRAM
+	select CRYPTO_DEV_MARVELL
+	help
+	  This driver allows you to utilize the Cryptographic Engines and
+	  Security Accelerator (CESA) which can be found on MVEBU and ORION
+	  platforms.
+	  This driver supports CPU offload through DMA transfers.
+
+config CRYPTO_DEV_OCTEONTX_CPT
+	tristate "Support for Marvell OcteonTX CPT driver"
+	depends on ARCH_THUNDER || COMPILE_TEST
+	depends on PCI_MSI && 64BIT
+	select CRYPTO_LIB_AES
+	select CRYPTO_SKCIPHER
+	select CRYPTO_HASH
+	select CRYPTO_AEAD
+	select CRYPTO_AUTHENC
+	select CRYPTO_DEV_MARVELL
+	help
+		This driver allows you to utilize the Marvell Cryptographic
+		Accelerator Unit(CPT) found in OcteonTX series of processors.
+
+		To compile this driver as module, choose M here:
+		the modules will be called octeontx-cpt and octeontx-cptvf
+
+config CRYPTO_DEV_OCTEONTX2_CPT
+	tristate "Marvell OcteonTX2 CPT driver"
+	depends on ARCH_THUNDER2 || COMPILE_TEST
+	depends on PCI_MSI && 64BIT
+	depends on NET_VENDOR_MARVELL
+	select OCTEONTX2_MBOX
+	select CRYPTO_DEV_MARVELL
+	select CRYPTO_LIB_AES
+	select CRYPTO_SKCIPHER
+	select CRYPTO_HASH
+	select CRYPTO_AEAD
+	select CRYPTO_AUTHENC
+	select NET_DEVLINK
+	help
+		This driver allows you to utilize the Marvell Cryptographic
+		Accelerator Unit(CPT) found in OcteonTX2 series of processors.