Changes in shadowstack.c

c17ee635fd3a482b2ad2bf5e269755c2eae5f25e - Merge drm/drm-fixes into drm-misc-fixes

Mon, 23 Feb 2026 09:09:45 +0000

Merge drm/drm-fixes into drm-misc-fixes7.0-rc1 was just released, let's merge it to kick the new release cycle.Signed-off-by: Maxime Ripard List of files: /linux/tools/testing/selftests/riscv/cfi/shadowstack.c

cee73b1e840c154f64ace682cb477c1ae2e29cc4 - Merge tag 'riscv-for-linus-7.0-mw1' of git://git.kernel.org/pub/scm/linux/kernel/git/riscv/linux

Fri, 13 Feb 2026 03:17:44 +0000

Merge tag 'riscv-for-linus-7.0-mw1' of git://git.kernel.org/pub/scm/linux/kernel/git/riscv/linuxPull RISC-V updates from Paul Walmsley: - Add support for control flow integrity for userspace processes. This is based on the standard RISC-V ISA extensions Zicfiss and Zicfilp - Improve ptrace behavior regarding vector registers, and add some selftests - Optimize our strlen() assembly - Enable the ISO-8859-1 code page as built-in, similar to ARM64, for EFI volume mounting - Clean up some code slightly, including defining copy_user_page() as copy_page() rather than memcpy(), aligning us with other architectures; and using max3() to slightly simplify an expression in riscv_iommu_init_check()* tag 'riscv-for-linus-7.0-mw1' of git://git.kernel.org/pub/scm/linux/kernel/git/riscv/linux: (42 commits) riscv: lib: optimize strlen loop efficiency selftests: riscv: vstate_exec_nolibc: Use the regular prctl() function selftests: riscv: verify ptrace accepts valid vector csr values selftests: riscv: verify ptrace rejects invalid vector csr inputs selftests: riscv: verify syscalls discard vector context selftests: riscv: verify initial vector state with ptrace selftests: riscv: test ptrace vector interface riscv: ptrace: validate input vector csr registers riscv: csr: define vtype register elements riscv: vector: init vector context with proper vlenb riscv: ptrace: return ENODATA for inactive vector extension kselftest/riscv: add kselftest for user mode CFI riscv: add documentation for shadow stack riscv: add documentation for landing pad / indirect branch tracking riscv: create a Kconfig fragment for shadow stack and landing pad support arch/riscv: add dual vdso creation logic and select vdso based on hw arch/riscv: compile vdso with landing pad and shadow stack note riscv: enable kernel access to shadow stack memory via the FWFT SBI call riscv: add kernel command line option to opt out of user CFI riscv/hwprobe: add zicfilp / zicfiss enumeration in hwprobe ... List of files: /linux/tools/testing/selftests/riscv/cfi/shadowstack.c

d30c1683aaecb93d2ab95685dc4300a33d3cea7a - kselftest/riscv: add kselftest for user mode CFI

Mon, 26 Jan 2026 04:09:56 +0000

kselftest/riscv: add kselftest for user mode CFIAdd a kselftest for RISC-V control flow integrity implementation foruser mode. There is not a lot going on in the kernel to enable landingpad for user mode. CFI selftests are intended to be compiled with azicfilp and zicfiss enabled compiler. This kselftest simply checks iflanding pads and shadow stacks for the process are enabled or not andexecutes ptrace selftests on CFI. The selftest then registers aSIGSEGV signal handler. Any control flow violations are reported asSIGSEGV with si_code = SEGV_CPERR. The test will fail on receivingany SEGV_CPERR. The shadow stack part has more changes in the kernel,and thus there are separate tests for that.- Exercise 'map_shadow_stack' syscall- 'fork' test to make sure COW works for shadow stack pages- gup tests Kernel uses FOLL_FORCE when access happens to memory via /proc//mem. Not breaking that for shadow stack.- signal test. Make sure signal delivery results in token creation on shadow stack and consumes (and verifies) token on sigreturn- shadow stack protection test. attempts to write using regular store instruction on shadow stack memory must result in access faults- ptrace test: adds landing pad violation, clears ELP and continuesIn case the toolchain doesn't support the CFI extension, the CFIkselftest won't be built.Test output==========="""TAP version 131..5 This is to ensure shadow stack is indeed enabled and working This is to ensure shadow stack is indeed enabled and workingok 1 shstk fork testok 2 map shadow stack syscallok 3 shadow stack gup testsok 4 shadow stack signal testsok 5 memory protections of shadow stack memory"""Suggested-by: Charlie Jenkins Signed-off-by: Charlie Jenkins Signed-off-by: Deepak Gupta Tested-by: Andreas Korb # QEMU, custom CVA6Tested-by: Valentin Haudiquet Link: https://patch.msgid.link/20251112-v5_user_cfi_series-v23-28-b55691eacf4f@rivosinc.com[pjw@kernel.org: updated to apply; cleaned up patch description, code comments]Signed-off-by: Paul Walmsley List of files: /linux/tools/testing/selftests/riscv/cfi/shadowstack.c