From c162cde9eaf50b92de5277df3e48c93349bf45a3 Mon Sep 17 00:00:00 2001 From: 6eanut Date: Thu, 22 Jan 2026 04:23:38 +0000 Subject: executor, sys/linux, pkg: enable syzos for riscv64 This patch enables syzos for riscv64 and implements the corresponding pseudo syscalls. Pseudo syscalls: - syz_kvm_setup_syzos_vm - syz_kvm_add_vcpu - syz_kvm_assert_syzos_uexit Syzos guest support: - guest_uexit - guest_execute_code - guest_handle_csrr and guest_handle_csrw Test seeds: - riscv64-syz_kvm_setup_syzos_vm - riscv64-syz_kvm_setup_syzos_vm-csrr - riscv64-syz_kvm_setup_syzos_vm-csrw --- sys/linux/test/riscv64-syz_kvm_setup_syzos_vm | 35 ++++++++++++++++++++++ sys/linux/test/riscv64-syz_kvm_setup_syzos_vm-csrr | 21 +++++++++++++ sys/linux/test/riscv64-syz_kvm_setup_syzos_vm-csrw | 22 ++++++++++++++ 3 files changed, 78 insertions(+) create mode 100644 sys/linux/test/riscv64-syz_kvm_setup_syzos_vm create mode 100644 sys/linux/test/riscv64-syz_kvm_setup_syzos_vm-csrr create mode 100644 sys/linux/test/riscv64-syz_kvm_setup_syzos_vm-csrw (limited to 'sys/linux/test') diff --git a/sys/linux/test/riscv64-syz_kvm_setup_syzos_vm b/sys/linux/test/riscv64-syz_kvm_setup_syzos_vm new file mode 100644 index 000000000..5942f1b9f --- /dev/null +++ b/sys/linux/test/riscv64-syz_kvm_setup_syzos_vm @@ -0,0 +1,35 @@ +# +# requires: arch=riscv64 -threaded +# + +r0 = openat$kvm(0, &AUTO='/dev/kvm\x00', 0x0, 0x0) +r1 = ioctl$KVM_CREATE_VM(r0, AUTO, 0x0) +r2 = syz_kvm_setup_syzos_vm$riscv64(r1, &(0x7f0000c00000/0x400000)=nil) + +# Perform two uexits. The first one is done via a code blob: +# lui a0, 0x40000 +# addi a0, a0, 0x100 # a0 = RISCV64_ADDR_UEXIT +# sd zero, 0(a0) +# ret +# The second uexit is done via a syzos API command that sets uexit exit code to 0xaaaa. +# +r3 = syz_kvm_add_vcpu$riscv64(r2, &AUTO={0x0, &AUTO=[@code={AUTO, AUTO, {"370500401305051023300500", 0x00008067}}, @uexit={AUTO, AUTO, 0xaaaa}], AUTO}, 0x0, 0x0) + +r4 = ioctl$KVM_GET_VCPU_MMAP_SIZE(r0, AUTO) +r5 = mmap$KVM_VCPU(&(0x7f0000009000/0x1000)=nil, r4, 0x3, 0x1, r3, 0x0) + +# Run till the first uexit. +# +ioctl$KVM_RUN(r3, AUTO, 0x0) +syz_kvm_assert_syzos_uexit$riscv64(r3, r5, 0x0) +# Run till the second uexit. +# +ioctl$KVM_RUN(r3, AUTO, 0x0) +syz_kvm_assert_syzos_uexit$riscv64(r3, r5, 0xaaaa) +# Run till the end of guest_main(). 0xffffffffffffffff is UEXIT_END. +# +ioctl$KVM_RUN(r3, AUTO, 0x0) +# Ensure that exit reason is KVM_EXIT_MMIO and uexit code is UEXIT_END. +# +syz_kvm_assert_syzos_kvm_exit$riscv64(r5, 0x6) +syz_kvm_assert_syzos_uexit$riscv64(r3, r5, 0xffffffffffffffff) diff --git a/sys/linux/test/riscv64-syz_kvm_setup_syzos_vm-csrr b/sys/linux/test/riscv64-syz_kvm_setup_syzos_vm-csrr new file mode 100644 index 000000000..77ea424df --- /dev/null +++ b/sys/linux/test/riscv64-syz_kvm_setup_syzos_vm-csrr @@ -0,0 +1,21 @@ +# +# requires: arch=riscv64 -threaded +# + +# This test verifies that SYZOS can safely execute CSR access instructions +# inside a RISC-V KVM guest. +# +r0 = openat$kvm(0, &AUTO='/dev/kvm\x00', 0x0, 0x0) +r1 = ioctl$KVM_CREATE_VM(r0, AUTO, 0x0) +r2 = syz_kvm_setup_syzos_vm$riscv64(r1, &(0x7f0000c00000/0x400000)=nil) + +# Number 0x140 is sscratch (encode). +# +r3 = syz_kvm_add_vcpu$riscv64(r2, &AUTO={0x0, &AUTO=[@csrr={AUTO, AUTO, {@valid=0x140}}], AUTO}, 0x0, 0x0) +r4 = ioctl$KVM_GET_VCPU_MMAP_SIZE(r0, AUTO) +r5 = mmap$KVM_VCPU(&(0x7f0000009000/0x1000)=nil, r4, 0x3, 0x1, r3, 0x0) + +# Run till end of guest_main(). +# +ioctl$KVM_RUN(r3, AUTO, 0x0) +syz_kvm_assert_syzos_uexit$riscv64(r3, r5, 0xffffffffffffffff) diff --git a/sys/linux/test/riscv64-syz_kvm_setup_syzos_vm-csrw b/sys/linux/test/riscv64-syz_kvm_setup_syzos_vm-csrw new file mode 100644 index 000000000..38fdd4929 --- /dev/null +++ b/sys/linux/test/riscv64-syz_kvm_setup_syzos_vm-csrw @@ -0,0 +1,22 @@ +# +# requires: arch=riscv64 -threaded +# + +# This test verifies that writing a supervisor CSR from the guest is +# correctly reflected in the KVM vCPU state. +# +r0 = openat$kvm(0, &AUTO='/dev/kvm\x00', 0x0, 0x0) +r1 = ioctl$KVM_CREATE_VM(r0, AUTO, 0x0) +r2 = syz_kvm_setup_syzos_vm$riscv64(r1, &(0x7f0000c00000/0x400000)=nil) + +# Number 0x140 is sscratch (encode). +# +r3 = syz_kvm_add_vcpu$riscv64(r2, &AUTO={0x0, &AUTO=[@csrw={AUTO, AUTO, {@valid=0x140, 0xfefefee0}}], AUTO}, 0x0, 0x0) +r4 = ioctl$KVM_GET_VCPU_MMAP_SIZE(r0, AUTO) +r5 = mmap$KVM_VCPU(&(0x7f0000009000/0x1000)=nil, r4, 0x3, 0x1, r3, 0x0) +ioctl$KVM_RUN(r3, AUTO, 0x0) +syz_kvm_assert_syzos_uexit$riscv64(r3, r5, 0xffffffffffffffff) + +# ID 0x8030000003000003 is sscratch (kvm reg id). +# +syz_kvm_assert_reg$riscv64(r3, 0x8030000003000003, 0xfefefee0) -- cgit mrf-deployment