// https://syzkaller.appspot.com/bug?id=2bf7b7983c2398ec6f0c4c6c87cb50223e8873f8 // autogenerated by syzkaller (http://github.com/google/syzkaller) #define _GNU_SOURCE #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include __attribute__((noreturn)) static void doexit(int status) { volatile unsigned i; syscall(__NR_exit_group, status); for (i = 0;; i++) { } } #include #include #include #include #include #include #include const int kFailStatus = 67; const int kRetryStatus = 69; static void fail(const char* msg, ...) { int e = errno; va_list args; va_start(args, msg); vfprintf(stderr, msg, args); va_end(args); fprintf(stderr, " (errno %d)\n", e); doexit((e == ENOMEM || e == EAGAIN) ? kRetryStatus : kFailStatus); } static void use_temporary_dir() { char tmpdir_template[] = "./syzkaller.XXXXXX"; char* tmpdir = mkdtemp(tmpdir_template); if (!tmpdir) fail("failed to mkdtemp"); if (chmod(tmpdir, 0777)) fail("failed to chmod"); if (chdir(tmpdir)) fail("failed to chdir"); } const char kvm_asm16_cpl3[] = "\x0f\x20\xc0\x66\x83\xc8\x01\x0f\x22\xc0\xb8\xa0" "\x00\x0f\x00\xd8\xb8\x2b\x00\x8e\xd8\x8e\xc0\x8e" "\xe0\x8e\xe8\xbc\x00\x01\xc7\x06\x00\x01\x1d\xba" "\xc7\x06\x02\x01\x23\x00\xc7\x06\x04\x01\x00\x01" "\xc7\x06\x06\x01\x2b\x00\xcb"; const char kvm_asm32_paged[] = "\x0f\x20\xc0\x0d\x00\x00\x00\x80\x0f\x22\xc0"; const char kvm_asm32_vm86[] = "\x66\xb8\xb8\x00\x0f\x00\xd8\xea\x00\x00\x00\x00\xd0\x00"; const char kvm_asm32_paged_vm86[] = "\x0f\x20\xc0\x0d\x00\x00\x00\x80\x0f\x22" "\xc0\x66\xb8\xb8\x00\x0f\x00\xd8\xea\x00" "\x00\x00\x00\xd0\x00"; const char kvm_asm64_vm86[] = "\x0f\x20\xc0\x0d\x00\x00\x00\x80\x0f\x22\xc0\x66" "\xb8\xb8\x00\x0f\x00\xd8\xea\x00\x00\x00\x00\xd0" "\x00"; const char kvm_asm64_enable_long[] = "\x0f\x20\xc0\x0d\x00\x00\x00\x80\x0f\x22" "\xc0\xea\xde\xc0\xad\x0b\x50\x00\x48\xc7" "\xc0\xd8\x00\x00\x00\x0f\x00\xd8"; const char kvm_asm64_init_vm[] = "\x0f\x20\xc0\x0d\x00\x00\x00\x80\x0f\x22\xc0\xea\xde\xc0\xad\x0b\x50\x00" "\x48\xc7\xc0\xd8\x00\x00\x00\x0f\x00\xd8\x48\xc7\xc1\x3a\x00\x00\x00\x0f" "\x32\x48\x83\xc8\x05\x0f\x30\x0f\x20\xe0\x48\x0d\x00\x20\x00\x00\x0f\x22" "\xe0\x48\xc7\xc1\x80\x04\x00\x00\x0f\x32\x48\xc7\xc2\x00\x60\x00\x00\x89" "\x02\x48\xc7\xc2\x00\x70\x00\x00\x89\x02\x48\xc7\xc0\x00\x5f\x00\x00\xf3" "\x0f\xc7\x30\x48\xc7\xc0\x08\x5f\x00\x00\x66\x0f\xc7\x30\x0f\xc7\x30\x48" "\xc7\xc1\x81\x04\x00\x00\x0f\x32\x48\x83\xc8\x3f\x48\x21\xd0\x48\xc7\xc2" "\x00\x40\x00\x00\x0f\x79\xd0\x48\xc7\xc2\x02\x40\x00\x00\x48\xb8\x84\x9e" "\x99\xf3\x00\x00\x00\x00\x0f\x79\xd0\x48\xc7\xc2\x1e\x40\x00\x00\x48\xc7" "\xc0\x81\x00\x00\x00\x0f\x79\xd0\x48\xc7\xc1\x83\x04\x00\x00\x0f\x32\x48" "\x0d\xff\x6f\x03\x00\x48\x21\xd0\x48\xc7\xc2\x0c\x40\x00\x00\x0f\x79\xd0" "\x48\xc7\xc1\x84\x04\x00\x00\x0f\x32\x48\x0d\xff\x17\x00\x00\x48\x21\xd0" "\x48\xc7\xc2\x12\x40\x00\x00\x0f\x79\xd0\x48\xc7\xc2\x04\x2c\x00\x00\x48" "\xc7\xc0\x00\x00\x00\x00\x0f\x79\xd0\x48\xc7\xc2\x00\x28\x00\x00\x48\xc7" "\xc0\xff\xff\xff\xff\x0f\x79\xd0\x48\xc7\xc2\x02\x0c\x00\x00\x48\xc7\xc0" "\x50\x00\x00\x00\x0f\x79\xd0\x48\xc7\xc0\x58\x00\x00\x00\x48\xc7\xc2\x00" "\x0c\x00\x00\x0f\x79\xd0\x48\xc7\xc2\x04\x0c\x00\x00\x0f\x79\xd0\x48\xc7" "\xc2\x06\x0c\x00\x00\x0f\x79\xd0\x48\xc7\xc2\x08\x0c\x00\x00\x0f\x79\xd0" "\x48\xc7\xc2\x0a\x0c\x00\x00\x0f\x79\xd0\x48\xc7\xc0\xd8\x00\x00\x00\x48" "\xc7\xc2\x0c\x0c\x00\x00\x0f\x79\xd0\x48\xc7\xc2\x02\x2c\x00\x00\x48\xc7" "\xc0\x00\x05\x00\x00\x0f\x79\xd0\x48\xc7\xc2\x00\x4c\x00\x00\x48\xc7\xc0" "\x50\x00\x00\x00\x0f\x79\xd0\x48\xc7\xc2\x10\x6c\x00\x00\x48\xc7\xc0\x00" "\x00\x00\x00\x0f\x79\xd0\x48\xc7\xc2\x12\x6c\x00\x00\x48\xc7\xc0\x00\x00" "\x00\x00\x0f\x79\xd0\x0f\x20\xc0\x48\xc7\xc2\x00\x6c\x00\x00\x48\x89\xc0" "\x0f\x79\xd0\x0f\x20\xd8\x48\xc7\xc2\x02\x6c\x00\x00\x48\x89\xc0\x0f\x79" "\xd0\x0f\x20\xe0\x48\xc7\xc2\x04\x6c\x00\x00\x48\x89\xc0\x0f\x79\xd0\x48" "\xc7\xc2\x06\x6c\x00\x00\x48\xc7\xc0\x00\x00\x00\x00\x0f\x79\xd0\x48\xc7" "\xc2\x08\x6c\x00\x00\x48\xc7\xc0\x00\x00\x00\x00\x0f\x79\xd0\x48\xc7\xc2" "\x0a\x6c\x00\x00\x48\xc7\xc0\x00\x3a\x00\x00\x0f\x79\xd0\x48\xc7\xc2\x0c" "\x6c\x00\x00\x48\xc7\xc0\x00\x10\x00\x00\x0f\x79\xd0\x48\xc7\xc2\x0e\x6c" "\x00\x00\x48\xc7\xc0\x00\x38\x00\x00\x0f\x79\xd0\x48\xc7\xc2\x14\x6c\x00" "\x00\x48\xc7\xc0\x00\x00\x00\x00\x0f\x79\xd0\x48\xc7\xc2\x16\x6c\x00\x00" "\x48\x8b\x04\x25\x10\x5f\x00\x00\x0f\x79\xd0\x48\xc7\xc2\x00\x00\x00\x00" "\x48\xc7\xc0\x01\x00\x00\x00\x0f\x79\xd0\x48\xc7\xc2\x02\x00\x00\x00\x48" "\xc7\xc0\x00\x00\x00\x00\x0f\x79\xd0\x48\xc7\xc2\x00\x20\x00\x00\x48\xc7" "\xc0\x00\x00\x00\x00\x0f\x79\xd0\x48\xc7\xc2\x02\x20\x00\x00\x48\xc7\xc0" "\x00\x00\x00\x00\x0f\x79\xd0\x48\xc7\xc2\x04\x20\x00\x00\x48\xc7\xc0\x00" "\x00\x00\x00\x0f\x79\xd0\x48\xc7\xc2\x06\x20\x00\x00\x48\xc7\xc0\x00\x00" "\x00\x00\x0f\x79\xd0\x48\xc7\xc1\x77\x02\x00\x00\x0f\x32\x48\xc1\xe2\x20" "\x48\x09\xd0\x48\xc7\xc2\x00\x2c\x00\x00\x48\x89\xc0\x0f\x79\xd0\x48\xc7" "\xc2\x04\x40\x00\x00\x48\xc7\xc0\x00\x00\x00\x00\x0f\x79\xd0\x48\xc7\xc2" "\x0a\x40\x00\x00\x48\xc7\xc0\x00\x00\x00\x00\x0f\x79\xd0\x48\xc7\xc2\x0e" "\x40\x00\x00\x48\xc7\xc0\x00\x00\x00\x00\x0f\x79\xd0\x48\xc7\xc2\x10\x40" "\x00\x00\x48\xc7\xc0\x00\x00\x00\x00\x0f\x79\xd0\x48\xc7\xc2\x16\x40\x00" "\x00\x48\xc7\xc0\x00\x00\x00\x00\x0f\x79\xd0\x48\xc7\xc2\x14\x40\x00\x00" "\x48\xc7\xc0\x00\x00\x00\x00\x0f\x79\xd0\x48\xc7\xc2\x00\x60\x00\x00\x48" "\xc7\xc0\xff\xff\xff\xff\x0f\x79\xd0\x48\xc7\xc2\x02\x60\x00\x00\x48\xc7" "\xc0\xff\xff\xff\xff\x0f\x79\xd0\x48\xc7\xc2\x1c\x20\x00\x00\x48\xc7\xc0" "\x00\x00\x00\x00\x0f\x79\xd0\x48\xc7\xc2\x1e\x20\x00\x00\x48\xc7\xc0\x00" "\x00\x00\x00\x0f\x79\xd0\x48\xc7\xc2\x20\x20\x00\x00\x48\xc7\xc0\x00\x00" "\x00\x00\x0f\x79\xd0\x48\xc7\xc2\x22\x20\x00\x00\x48\xc7\xc0\x00\x00\x00" "\x00\x0f\x79\xd0\x48\xc7\xc2\x00\x08\x00\x00\x48\xc7\xc0\x58\x00\x00\x00" "\x0f\x79\xd0\x48\xc7\xc2\x02\x08\x00\x00\x48\xc7\xc0\x50\x00\x00\x00\x0f" "\x79\xd0\x48\xc7\xc2\x04\x08\x00\x00\x48\xc7\xc0\x58\x00\x00\x00\x0f\x79" "\xd0\x48\xc7\xc2\x06\x08\x00\x00\x48\xc7\xc0\x58\x00\x00\x00\x0f\x79\xd0" "\x48\xc7\xc2\x08\x08\x00\x00\x48\xc7\xc0\x58\x00\x00\x00\x0f\x79\xd0\x48" "\xc7\xc2\x0a\x08\x00\x00\x48\xc7\xc0\x58\x00\x00\x00\x0f\x79\xd0\x48\xc7" "\xc2\x0c\x08\x00\x00\x48\xc7\xc0\x00\x00\x00\x00\x0f\x79\xd0\x48\xc7\xc2" "\x0e\x08\x00\x00\x48\xc7\xc0\xd8\x00\x00\x00\x0f\x79\xd0\x48\xc7\xc2\x12" "\x68\x00\x00\x48\xc7\xc0\x00\x00\x00\x00\x0f\x79\xd0\x48\xc7\xc2\x14\x68" "\x00\x00\x48\xc7\xc0\x00\x3a\x00\x00\x0f\x79\xd0\x48\xc7\xc2\x16\x68\x00" "\x00\x48\xc7\xc0\x00\x10\x00\x00\x0f\x79\xd0\x48\xc7\xc2\x18\x68\x00\x00" "\x48\xc7\xc0\x00\x38\x00\x00\x0f\x79\xd0\x48\xc7\xc2\x00\x48\x00\x00\x48" "\xc7\xc0\xff\xff\x0f\x00\x0f\x79\xd0\x48\xc7\xc2\x02\x48\x00\x00\x48\xc7" "\xc0\xff\xff\x0f\x00\x0f\x79\xd0\x48\xc7\xc2\x04\x48\x00\x00\x48\xc7\xc0" "\xff\xff\x0f\x00\x0f\x79\xd0\x48\xc7\xc2\x06\x48\x00\x00\x48\xc7\xc0\xff" "\xff\x0f\x00\x0f\x79\xd0\x48\xc7\xc2\x08\x48\x00\x00\x48\xc7\xc0\xff\xff" "\x0f\x00\x0f\x79\xd0\x48\xc7\xc2\x0a\x48\x00\x00\x48\xc7\xc0\xff\xff\x0f" "\x00\x0f\x79\xd0\x48\xc7\xc2\x0c\x48\x00\x00\x48\xc7\xc0\x00\x00\x00\x00" "\x0f\x79\xd0\x48\xc7\xc2\x0e\x48\x00\x00\x48\xc7\xc0\xff\x1f\x00\x00\x0f" "\x79\xd0\x48\xc7\xc2\x10\x48\x00\x00\x48\xc7\xc0\xff\x1f\x00\x00\x0f\x79" "\xd0\x48\xc7\xc2\x12\x48\x00\x00\x48\xc7\xc0\xff\x1f\x00\x00\x0f\x79\xd0" "\x48\xc7\xc2\x14\x48\x00\x00\x48\xc7\xc0\x93\x40\x00\x00\x0f\x79\xd0\x48" "\xc7\xc2\x16\x48\x00\x00\x48\xc7\xc0\x9b\x20\x00\x00\x0f\x79\xd0\x48\xc7" "\xc2\x18\x48\x00\x00\x48\xc7\xc0\x93\x40\x00\x00\x0f\x79\xd0\x48\xc7\xc2" "\x1a\x48\x00\x00\x48\xc7\xc0\x93\x40\x00\x00\x0f\x79\xd0\x48\xc7\xc2\x1c" "\x48\x00\x00\x48\xc7\xc0\x93\x40\x00\x00\x0f\x79\xd0\x48\xc7\xc2\x1e\x48" "\x00\x00\x48\xc7\xc0\x93\x40\x00\x00\x0f\x79\xd0\x48\xc7\xc2\x20\x48\x00" "\x00\x48\xc7\xc0\x82\x00\x00\x00\x0f\x79\xd0\x48\xc7\xc2\x22\x48\x00\x00" "\x48\xc7\xc0\x8b\x00\x00\x00\x0f\x79\xd0\x48\xc7\xc2\x1c\x68\x00\x00\x48" "\xc7\xc0\x00\x00\x00\x00\x0f\x79\xd0\x48\xc7\xc2\x1e\x68\x00\x00\x48\xc7" "\xc0\x00\x91\x00\x00\x0f\x79\xd0\x48\xc7\xc2\x20\x68\x00\x00\x48\xc7\xc0" "\x02\x00\x00\x00\x0f\x79\xd0\x48\xc7\xc2\x06\x28\x00\x00\x48\xc7\xc0\x00" "\x05\x00\x00\x0f\x79\xd0\x48\xc7\xc2\x0a\x28\x00\x00\x48\xc7\xc0\x00\x00" "\x00\x00\x0f\x79\xd0\x48\xc7\xc2\x0c\x28\x00\x00\x48\xc7\xc0\x00\x00\x00" "\x00\x0f\x79\xd0\x48\xc7\xc2\x0e\x28\x00\x00\x48\xc7\xc0\x00\x00\x00\x00" "\x0f\x79\xd0\x48\xc7\xc2\x10\x28\x00\x00\x48\xc7\xc0\x00\x00\x00\x00\x0f" "\x79\xd0\x0f\x20\xc0\x48\xc7\xc2\x00\x68\x00\x00\x48\x89\xc0\x0f\x79\xd0" "\x0f\x20\xd8\x48\xc7\xc2\x02\x68\x00\x00\x48\x89\xc0\x0f\x79\xd0\x0f\x20" "\xe0\x48\xc7\xc2\x04\x68\x00\x00\x48\x89\xc0\x0f\x79\xd0\x48\xc7\xc0\x18" "\x5f\x00\x00\x48\x8b\x10\x48\xc7\xc0\x20\x5f\x00\x00\x48\x8b\x08\x48\x31" "\xc0\x0f\x78\xd0\x48\x31\xc8\x0f\x79\xd0\x0f\x01\xc2\x48\xc7\xc2\x00\x44" "\x00\x00\x0f\x78\xd0\xf4"; const char kvm_asm64_vm_exit[] = "\x48\xc7\xc3\x00\x44\x00\x00\x0f\x78\xda\x48" "\xc7\xc3\x02\x44\x00\x00\x0f\x78\xd9\x48\xc7" "\xc0\x00\x64\x00\x00\x0f\x78\xc0\x48\xc7\xc3" "\x1e\x68\x00\x00\x0f\x78\xdb\xf4"; const char kvm_asm64_cpl3[] = "\x0f\x20\xc0\x0d\x00\x00\x00\x80\x0f\x22\xc0\xea\xde\xc0\xad\x0b\x50\x00" "\x48\xc7\xc0\xd8\x00\x00\x00\x0f\x00\xd8\x48\xc7\xc0\x6b\x00\x00\x00\x8e" "\xd8\x8e\xc0\x8e\xe0\x8e\xe8\x48\xc7\xc4\x80\x0f\x00\x00\x48\xc7\x04\x24" "\x1d\xba\x00\x00\x48\xc7\x44\x24\x04\x63\x00\x00\x00\x48\xc7\x44\x24\x08" "\x80\x0f\x00\x00\x48\xc7\x44\x24\x0c\x6b\x00\x00\x00\xcb"; #define ADDR_TEXT 0x0000 #define ADDR_GDT 0x1000 #define ADDR_LDT 0x1800 #define ADDR_PML4 0x2000 #define ADDR_PDP 0x3000 #define ADDR_PD 0x4000 #define ADDR_STACK0 0x0f80 #define ADDR_VAR_HLT 0x2800 #define ADDR_VAR_SYSRET 0x2808 #define ADDR_VAR_SYSEXIT 0x2810 #define ADDR_VAR_IDT 0x3800 #define ADDR_VAR_TSS64 0x3a00 #define ADDR_VAR_TSS64_CPL3 0x3c00 #define ADDR_VAR_TSS16 0x3d00 #define ADDR_VAR_TSS16_2 0x3e00 #define ADDR_VAR_TSS16_CPL3 0x3f00 #define ADDR_VAR_TSS32 0x4800 #define ADDR_VAR_TSS32_2 0x4a00 #define ADDR_VAR_TSS32_CPL3 0x4c00 #define ADDR_VAR_TSS32_VM86 0x4e00 #define ADDR_VAR_VMXON_PTR 0x5f00 #define ADDR_VAR_VMCS_PTR 0x5f08 #define ADDR_VAR_VMEXIT_PTR 0x5f10 #define ADDR_VAR_VMWRITE_FLD 0x5f18 #define ADDR_VAR_VMWRITE_VAL 0x5f20 #define ADDR_VAR_VMXON 0x6000 #define ADDR_VAR_VMCS 0x7000 #define ADDR_VAR_VMEXIT_CODE 0x9000 #define ADDR_VAR_USER_CODE 0x9100 #define ADDR_VAR_USER_CODE2 0x9120 #define SEL_LDT (1 << 3) #define SEL_CS16 (2 << 3) #define SEL_DS16 (3 << 3) #define SEL_CS16_CPL3 ((4 << 3) + 3) #define SEL_DS16_CPL3 ((5 << 3) + 3) #define SEL_CS32 (6 << 3) #define SEL_DS32 (7 << 3) #define SEL_CS32_CPL3 ((8 << 3) + 3) #define SEL_DS32_CPL3 ((9 << 3) + 3) #define SEL_CS64 (10 << 3) #define SEL_DS64 (11 << 3) #define SEL_CS64_CPL3 ((12 << 3) + 3) #define SEL_DS64_CPL3 ((13 << 3) + 3) #define SEL_CGATE16 (14 << 3) #define SEL_TGATE16 (15 << 3) #define SEL_CGATE32 (16 << 3) #define SEL_TGATE32 (17 << 3) #define SEL_CGATE64 (18 << 3) #define SEL_CGATE64_HI (19 << 3) #define SEL_TSS16 (20 << 3) #define SEL_TSS16_2 (21 << 3) #define SEL_TSS16_CPL3 ((22 << 3) + 3) #define SEL_TSS32 (23 << 3) #define SEL_TSS32_2 (24 << 3) #define SEL_TSS32_CPL3 ((25 << 3) + 3) #define SEL_TSS32_VM86 (26 << 3) #define SEL_TSS64 (27 << 3) #define SEL_TSS64_HI (28 << 3) #define SEL_TSS64_CPL3 ((29 << 3) + 3) #define SEL_TSS64_CPL3_HI (30 << 3) #define MSR_IA32_FEATURE_CONTROL 0x3a #define MSR_IA32_VMX_BASIC 0x480 #define MSR_IA32_SMBASE 0x9e #define MSR_IA32_SYSENTER_CS 0x174 #define MSR_IA32_SYSENTER_ESP 0x175 #define MSR_IA32_SYSENTER_EIP 0x176 #define MSR_IA32_STAR 0xC0000081 #define MSR_IA32_LSTAR 0xC0000082 #define MSR_IA32_VMX_PROCBASED_CTLS2 0x48B #define NEXT_INSN $0xbadc0de #define PREFIX_SIZE 0xba1d #define KVM_SMI _IO(KVMIO, 0xb7) #define CR0_PE 1 #define CR0_MP (1 << 1) #define CR0_EM (1 << 2) #define CR0_TS (1 << 3) #define CR0_ET (1 << 4) #define CR0_NE (1 << 5) #define CR0_WP (1 << 16) #define CR0_AM (1 << 18) #define CR0_NW (1 << 29) #define CR0_CD (1 << 30) #define CR0_PG (1 << 31) #define CR4_VME 1 #define CR4_PVI (1 << 1) #define CR4_TSD (1 << 2) #define CR4_DE (1 << 3) #define CR4_PSE (1 << 4) #define CR4_PAE (1 << 5) #define CR4_MCE (1 << 6) #define CR4_PGE (1 << 7) #define CR4_PCE (1 << 8) #define CR4_OSFXSR (1 << 8) #define CR4_OSXMMEXCPT (1 << 10) #define CR4_UMIP (1 << 11) #define CR4_VMXE (1 << 13) #define CR4_SMXE (1 << 14) #define CR4_FSGSBASE (1 << 16) #define CR4_PCIDE (1 << 17) #define CR4_OSXSAVE (1 << 18) #define CR4_SMEP (1 << 20) #define CR4_SMAP (1 << 21) #define CR4_PKE (1 << 22) #define EFER_SCE 1 #define EFER_LME (1 << 8) #define EFER_LMA (1 << 10) #define EFER_NXE (1 << 11) #define EFER_SVME (1 << 12) #define EFER_LMSLE (1 << 13) #define EFER_FFXSR (1 << 14) #define EFER_TCE (1 << 15) #define PDE32_PRESENT 1 #define PDE32_RW (1 << 1) #define PDE32_USER (1 << 2) #define PDE32_PS (1 << 7) #define PDE64_PRESENT 1 #define PDE64_RW (1 << 1) #define PDE64_USER (1 << 2) #define PDE64_ACCESSED (1 << 5) #define PDE64_DIRTY (1 << 6) #define PDE64_PS (1 << 7) #define PDE64_G (1 << 8) struct tss16 { uint16_t prev; uint16_t sp0; uint16_t ss0; uint16_t sp1; uint16_t ss1; uint16_t sp2; uint16_t ss2; uint16_t ip; uint16_t flags; uint16_t ax; uint16_t cx; uint16_t dx; uint16_t bx; uint16_t sp; uint16_t bp; uint16_t si; uint16_t di; uint16_t es; uint16_t cs; uint16_t ss; uint16_t ds; uint16_t ldt; } __attribute__((packed)); struct tss32 { uint16_t prev, prevh; uint32_t sp0; uint16_t ss0, ss0h; uint32_t sp1; uint16_t ss1, ss1h; uint32_t sp2; uint16_t ss2, ss2h; uint32_t cr3; uint32_t ip; uint32_t flags; uint32_t ax; uint32_t cx; uint32_t dx; uint32_t bx; uint32_t sp; uint32_t bp; uint32_t si; uint32_t di; uint16_t es, esh; uint16_t cs, csh; uint16_t ss, ssh; uint16_t ds, dsh; uint16_t fs, fsh; uint16_t gs, gsh; uint16_t ldt, ldth; uint16_t trace; uint16_t io_bitmap; } __attribute__((packed)); struct tss64 { uint32_t reserved0; uint64_t rsp[3]; uint64_t reserved1; uint64_t ist[7]; uint64_t reserved2; uint32_t reserved3; uint32_t io_bitmap; } __attribute__((packed)); static void fill_segment_descriptor(uint64_t* dt, uint64_t* lt, struct kvm_segment* seg) { uint16_t index = seg->selector >> 3; uint64_t limit = seg->g ? seg->limit >> 12 : seg->limit; uint64_t sd = (limit & 0xffff) | (seg->base & 0xffffff) << 16 | (uint64_t)seg->type << 40 | (uint64_t)seg->s << 44 | (uint64_t)seg->dpl << 45 | (uint64_t)seg->present << 47 | (limit & 0xf0000ULL) << 48 | (uint64_t)seg->avl << 52 | (uint64_t)seg->l << 53 | (uint64_t)seg->db << 54 | (uint64_t)seg->g << 55 | (seg->base & 0xff000000ULL) << 56; dt[index] = sd; lt[index] = sd; } static void fill_segment_descriptor_dword(uint64_t* dt, uint64_t* lt, struct kvm_segment* seg) { fill_segment_descriptor(dt, lt, seg); uint16_t index = seg->selector >> 3; dt[index + 1] = 0; lt[index + 1] = 0; } static void setup_syscall_msrs(int cpufd, uint16_t sel_cs, uint16_t sel_cs_cpl3) { char buf[sizeof(struct kvm_msrs) + 5 * sizeof(struct kvm_msr_entry)]; memset(buf, 0, sizeof(buf)); struct kvm_msrs* msrs = (struct kvm_msrs*)buf; msrs->nmsrs = 5; msrs->entries[0].index = MSR_IA32_SYSENTER_CS; msrs->entries[0].data = sel_cs; msrs->entries[1].index = MSR_IA32_SYSENTER_ESP; msrs->entries[1].data = ADDR_STACK0; msrs->entries[2].index = MSR_IA32_SYSENTER_EIP; msrs->entries[2].data = ADDR_VAR_SYSEXIT; msrs->entries[3].index = MSR_IA32_STAR; msrs->entries[3].data = ((uint64_t)sel_cs << 32) | ((uint64_t)sel_cs_cpl3 << 48); msrs->entries[4].index = MSR_IA32_LSTAR; msrs->entries[4].data = ADDR_VAR_SYSRET; ioctl(cpufd, KVM_SET_MSRS, msrs); } static void setup_32bit_idt(struct kvm_sregs* sregs, char* host_mem, uintptr_t guest_mem) { sregs->idt.base = guest_mem + ADDR_VAR_IDT; sregs->idt.limit = 0x1ff; uint64_t* idt = (uint64_t*)(host_mem + sregs->idt.base); int i; for (i = 0; i < 32; i++) { struct kvm_segment gate; gate.selector = i << 3; switch (i % 6) { case 0: gate.type = 6; gate.base = SEL_CS16; break; case 1: gate.type = 7; gate.base = SEL_CS16; break; case 2: gate.type = 3; gate.base = SEL_TGATE16; break; case 3: gate.type = 14; gate.base = SEL_CS32; break; case 4: gate.type = 15; gate.base = SEL_CS32; break; case 6: gate.type = 11; gate.base = SEL_TGATE32; break; } gate.limit = guest_mem + ADDR_VAR_USER_CODE2; gate.present = 1; gate.dpl = 0; gate.s = 0; gate.g = 0; gate.db = 0; gate.l = 0; gate.avl = 0; fill_segment_descriptor(idt, idt, &gate); } } static void setup_64bit_idt(struct kvm_sregs* sregs, char* host_mem, uintptr_t guest_mem) { sregs->idt.base = guest_mem + ADDR_VAR_IDT; sregs->idt.limit = 0x1ff; uint64_t* idt = (uint64_t*)(host_mem + sregs->idt.base); int i; for (i = 0; i < 32; i++) { struct kvm_segment gate; gate.selector = (i * 2) << 3; gate.type = (i & 1) ? 14 : 15; gate.base = SEL_CS64; gate.limit = guest_mem + ADDR_VAR_USER_CODE2; gate.present = 1; gate.dpl = 0; gate.s = 0; gate.g = 0; gate.db = 0; gate.l = 0; gate.avl = 0; fill_segment_descriptor_dword(idt, idt, &gate); } } struct kvm_text { uintptr_t typ; const void* text; uintptr_t size; }; struct kvm_opt { uint64_t typ; uint64_t val; }; #define KVM_SETUP_PAGING (1 << 0) #define KVM_SETUP_PAE (1 << 1) #define KVM_SETUP_PROTECTED (1 << 2) #define KVM_SETUP_CPL3 (1 << 3) #define KVM_SETUP_VIRT86 (1 << 4) #define KVM_SETUP_SMM (1 << 5) #define KVM_SETUP_VM (1 << 6) static uintptr_t syz_kvm_setup_cpu(uintptr_t a0, uintptr_t a1, uintptr_t a2, uintptr_t a3, uintptr_t a4, uintptr_t a5, uintptr_t a6, uintptr_t a7) { const int vmfd = a0; const int cpufd = a1; char* const host_mem = (char*)a2; const struct kvm_text* const text_array_ptr = (struct kvm_text*)a3; const uintptr_t text_count = a4; const uintptr_t flags = a5; const struct kvm_opt* const opt_array_ptr = (struct kvm_opt*)a6; uintptr_t opt_count = a7; const uintptr_t page_size = 4 << 10; const uintptr_t ioapic_page = 10; const uintptr_t guest_mem_size = 24 * page_size; const uintptr_t guest_mem = 0; (void)text_count; int text_type = 0; const void* text = 0; uintptr_t text_size = 0; text_type = text_array_ptr[0].typ; text = text_array_ptr[0].text; text_size = text_array_ptr[0].size; uintptr_t i; for (i = 0; i < guest_mem_size / page_size; i++) { struct kvm_userspace_memory_region memreg; memreg.slot = i; memreg.flags = 0; memreg.guest_phys_addr = guest_mem + i * page_size; if (i == ioapic_page) memreg.guest_phys_addr = 0xfec00000; memreg.memory_size = page_size; memreg.userspace_addr = (uintptr_t)host_mem + i * page_size; ioctl(vmfd, KVM_SET_USER_MEMORY_REGION, &memreg); } struct kvm_userspace_memory_region memreg; memreg.slot = 1 + (1 << 16); memreg.flags = 0; memreg.guest_phys_addr = 0x30000; memreg.memory_size = 64 << 10; memreg.userspace_addr = (uintptr_t)host_mem; ioctl(vmfd, KVM_SET_USER_MEMORY_REGION, &memreg); struct kvm_sregs sregs; if (ioctl(cpufd, KVM_GET_SREGS, &sregs)) return -1; struct kvm_regs regs; memset(®s, 0, sizeof(regs)); regs.rip = guest_mem + ADDR_TEXT; regs.rsp = ADDR_STACK0; sregs.gdt.base = guest_mem + ADDR_GDT; sregs.gdt.limit = 256 * sizeof(uint64_t) - 1; uint64_t* gdt = (uint64_t*)(host_mem + sregs.gdt.base); struct kvm_segment seg_ldt; seg_ldt.selector = SEL_LDT; seg_ldt.type = 2; seg_ldt.base = guest_mem + ADDR_LDT; seg_ldt.limit = 256 * sizeof(uint64_t) - 1; seg_ldt.present = 1; seg_ldt.dpl = 0; seg_ldt.s = 0; seg_ldt.g = 0; seg_ldt.db = 1; seg_ldt.l = 0; sregs.ldt = seg_ldt; uint64_t* ldt = (uint64_t*)(host_mem + sregs.ldt.base); struct kvm_segment seg_cs16; seg_cs16.selector = SEL_CS16; seg_cs16.type = 11; seg_cs16.base = 0; seg_cs16.limit = 0xfffff; seg_cs16.present = 1; seg_cs16.dpl = 0; seg_cs16.s = 1; seg_cs16.g = 0; seg_cs16.db = 0; seg_cs16.l = 0; struct kvm_segment seg_ds16 = seg_cs16; seg_ds16.selector = SEL_DS16; seg_ds16.type = 3; struct kvm_segment seg_cs16_cpl3 = seg_cs16; seg_cs16_cpl3.selector = SEL_CS16_CPL3; seg_cs16_cpl3.dpl = 3; struct kvm_segment seg_ds16_cpl3 = seg_ds16; seg_ds16_cpl3.selector = SEL_DS16_CPL3; seg_ds16_cpl3.dpl = 3; struct kvm_segment seg_cs32 = seg_cs16; seg_cs32.selector = SEL_CS32; seg_cs32.db = 1; struct kvm_segment seg_ds32 = seg_ds16; seg_ds32.selector = SEL_DS32; seg_ds32.db = 1; struct kvm_segment seg_cs32_cpl3 = seg_cs32; seg_cs32_cpl3.selector = SEL_CS32_CPL3; seg_cs32_cpl3.dpl = 3; struct kvm_segment seg_ds32_cpl3 = seg_ds32; seg_ds32_cpl3.selector = SEL_DS32_CPL3; seg_ds32_cpl3.dpl = 3; struct kvm_segment seg_cs64 = seg_cs16; seg_cs64.selector = SEL_CS64; seg_cs64.l = 1; struct kvm_segment seg_ds64 = seg_ds32; seg_ds64.selector = SEL_DS64; struct kvm_segment seg_cs64_cpl3 = seg_cs64; seg_cs64_cpl3.selector = SEL_CS64_CPL3; seg_cs64_cpl3.dpl = 3; struct kvm_segment seg_ds64_cpl3 = seg_ds64; seg_ds64_cpl3.selector = SEL_DS64_CPL3; seg_ds64_cpl3.dpl = 3; struct kvm_segment seg_tss32; seg_tss32.selector = SEL_TSS32; seg_tss32.type = 9; seg_tss32.base = ADDR_VAR_TSS32; seg_tss32.limit = 0x1ff; seg_tss32.present = 1; seg_tss32.dpl = 0; seg_tss32.s = 0; seg_tss32.g = 0; seg_tss32.db = 0; seg_tss32.l = 0; struct kvm_segment seg_tss32_2 = seg_tss32; seg_tss32_2.selector = SEL_TSS32_2; seg_tss32_2.base = ADDR_VAR_TSS32_2; struct kvm_segment seg_tss32_cpl3 = seg_tss32; seg_tss32_cpl3.selector = SEL_TSS32_CPL3; seg_tss32_cpl3.base = ADDR_VAR_TSS32_CPL3; struct kvm_segment seg_tss32_vm86 = seg_tss32; seg_tss32_vm86.selector = SEL_TSS32_VM86; seg_tss32_vm86.base = ADDR_VAR_TSS32_VM86; struct kvm_segment seg_tss16 = seg_tss32; seg_tss16.selector = SEL_TSS16; seg_tss16.base = ADDR_VAR_TSS16; seg_tss16.limit = 0xff; seg_tss16.type = 1; struct kvm_segment seg_tss16_2 = seg_tss16; seg_tss16_2.selector = SEL_TSS16_2; seg_tss16_2.base = ADDR_VAR_TSS16_2; seg_tss16_2.dpl = 0; struct kvm_segment seg_tss16_cpl3 = seg_tss16; seg_tss16_cpl3.selector = SEL_TSS16_CPL3; seg_tss16_cpl3.base = ADDR_VAR_TSS16_CPL3; seg_tss16_cpl3.dpl = 3; struct kvm_segment seg_tss64 = seg_tss32; seg_tss64.selector = SEL_TSS64; seg_tss64.base = ADDR_VAR_TSS64; seg_tss64.limit = 0x1ff; struct kvm_segment seg_tss64_cpl3 = seg_tss64; seg_tss64_cpl3.selector = SEL_TSS64_CPL3; seg_tss64_cpl3.base = ADDR_VAR_TSS64_CPL3; seg_tss64_cpl3.dpl = 3; struct kvm_segment seg_cgate16; seg_cgate16.selector = SEL_CGATE16; seg_cgate16.type = 4; seg_cgate16.base = SEL_CS16 | (2 << 16); seg_cgate16.limit = ADDR_VAR_USER_CODE2; seg_cgate16.present = 1; seg_cgate16.dpl = 0; seg_cgate16.s = 0; seg_cgate16.g = 0; seg_cgate16.db = 0; seg_cgate16.l = 0; seg_cgate16.avl = 0; struct kvm_segment seg_tgate16 = seg_cgate16; seg_tgate16.selector = SEL_TGATE16; seg_tgate16.type = 3; seg_cgate16.base = SEL_TSS16_2; seg_tgate16.limit = 0; struct kvm_segment seg_cgate32 = seg_cgate16; seg_cgate32.selector = SEL_CGATE32; seg_cgate32.type = 12; seg_cgate32.base = SEL_CS32 | (2 << 16); struct kvm_segment seg_tgate32 = seg_cgate32; seg_tgate32.selector = SEL_TGATE32; seg_tgate32.type = 11; seg_tgate32.base = SEL_TSS32_2; seg_tgate32.limit = 0; struct kvm_segment seg_cgate64 = seg_cgate16; seg_cgate64.selector = SEL_CGATE64; seg_cgate64.type = 12; seg_cgate64.base = SEL_CS64; int kvmfd = open("/dev/kvm", O_RDWR); char buf[sizeof(struct kvm_cpuid2) + 128 * sizeof(struct kvm_cpuid_entry2)]; memset(buf, 0, sizeof(buf)); struct kvm_cpuid2* cpuid = (struct kvm_cpuid2*)buf; cpuid->nent = 128; ioctl(kvmfd, KVM_GET_SUPPORTED_CPUID, cpuid); ioctl(cpufd, KVM_SET_CPUID2, cpuid); close(kvmfd); const char* text_prefix = 0; int text_prefix_size = 0; char* host_text = host_mem + ADDR_TEXT; if (text_type == 8) { if (flags & KVM_SETUP_SMM) { if (flags & KVM_SETUP_PROTECTED) { sregs.cs = seg_cs16; sregs.ds = sregs.es = sregs.fs = sregs.gs = sregs.ss = seg_ds16; sregs.cr0 |= CR0_PE; } else { sregs.cs.selector = 0; sregs.cs.base = 0; } *(host_mem + ADDR_TEXT) = 0xf4; host_text = host_mem + 0x8000; ioctl(cpufd, KVM_SMI, 0); } else if (flags & KVM_SETUP_VIRT86) { sregs.cs = seg_cs32; sregs.ds = sregs.es = sregs.fs = sregs.gs = sregs.ss = seg_ds32; sregs.cr0 |= CR0_PE; sregs.efer |= EFER_SCE; setup_syscall_msrs(cpufd, SEL_CS32, SEL_CS32_CPL3); setup_32bit_idt(&sregs, host_mem, guest_mem); if (flags & KVM_SETUP_PAGING) { uint64_t pd_addr = guest_mem + ADDR_PD; uint64_t* pd = (uint64_t*)(host_mem + ADDR_PD); pd[0] = PDE32_PRESENT | PDE32_RW | PDE32_USER | PDE32_PS; sregs.cr3 = pd_addr; sregs.cr4 |= CR4_PSE; text_prefix = kvm_asm32_paged_vm86; text_prefix_size = sizeof(kvm_asm32_paged_vm86) - 1; } else { text_prefix = kvm_asm32_vm86; text_prefix_size = sizeof(kvm_asm32_vm86) - 1; } } else { sregs.cs.selector = 0; sregs.cs.base = 0; } } else if (text_type == 16) { if (flags & KVM_SETUP_CPL3) { sregs.cs = seg_cs16; sregs.ds = sregs.es = sregs.fs = sregs.gs = sregs.ss = seg_ds16; text_prefix = kvm_asm16_cpl3; text_prefix_size = sizeof(kvm_asm16_cpl3) - 1; } else { sregs.cr0 |= CR0_PE; sregs.cs = seg_cs16; sregs.ds = sregs.es = sregs.fs = sregs.gs = sregs.ss = seg_ds16; } } else if (text_type == 32) { sregs.cr0 |= CR0_PE; sregs.efer |= EFER_SCE; setup_syscall_msrs(cpufd, SEL_CS32, SEL_CS32_CPL3); setup_32bit_idt(&sregs, host_mem, guest_mem); if (flags & KVM_SETUP_SMM) { sregs.cs = seg_cs32; sregs.ds = sregs.es = sregs.fs = sregs.gs = sregs.ss = seg_ds32; *(host_mem + ADDR_TEXT) = 0xf4; host_text = host_mem + 0x8000; ioctl(cpufd, KVM_SMI, 0); } else if (flags & KVM_SETUP_PAGING) { sregs.cs = seg_cs32; sregs.ds = sregs.es = sregs.fs = sregs.gs = sregs.ss = seg_ds32; uint64_t pd_addr = guest_mem + ADDR_PD; uint64_t* pd = (uint64_t*)(host_mem + ADDR_PD); pd[0] = PDE32_PRESENT | PDE32_RW | PDE32_USER | PDE32_PS; sregs.cr3 = pd_addr; sregs.cr4 |= CR4_PSE; text_prefix = kvm_asm32_paged; text_prefix_size = sizeof(kvm_asm32_paged) - 1; } else if (flags & KVM_SETUP_CPL3) { sregs.cs = seg_cs32_cpl3; sregs.ds = sregs.es = sregs.fs = sregs.gs = sregs.ss = seg_ds32_cpl3; } else { sregs.cs = seg_cs32; sregs.ds = sregs.es = sregs.fs = sregs.gs = sregs.ss = seg_ds32; } } else { sregs.efer |= EFER_LME | EFER_SCE; sregs.cr0 |= CR0_PE; setup_syscall_msrs(cpufd, SEL_CS64, SEL_CS64_CPL3); setup_64bit_idt(&sregs, host_mem, guest_mem); sregs.cs = seg_cs32; sregs.ds = sregs.es = sregs.fs = sregs.gs = sregs.ss = seg_ds32; uint64_t pml4_addr = guest_mem + ADDR_PML4; uint64_t* pml4 = (uint64_t*)(host_mem + ADDR_PML4); uint64_t pdpt_addr = guest_mem + ADDR_PDP; uint64_t* pdpt = (uint64_t*)(host_mem + ADDR_PDP); uint64_t pd_addr = guest_mem + ADDR_PD; uint64_t* pd = (uint64_t*)(host_mem + ADDR_PD); pml4[0] = PDE64_PRESENT | PDE64_RW | PDE64_USER | pdpt_addr; pdpt[0] = PDE64_PRESENT | PDE64_RW | PDE64_USER | pd_addr; pd[0] = PDE64_PRESENT | PDE64_RW | PDE64_USER | PDE64_PS; sregs.cr3 = pml4_addr; sregs.cr4 |= CR4_PAE; if (flags & KVM_SETUP_VM) { sregs.cr0 |= CR0_NE; *((uint64_t*)(host_mem + ADDR_VAR_VMXON_PTR)) = ADDR_VAR_VMXON; *((uint64_t*)(host_mem + ADDR_VAR_VMCS_PTR)) = ADDR_VAR_VMCS; memcpy(host_mem + ADDR_VAR_VMEXIT_CODE, kvm_asm64_vm_exit, sizeof(kvm_asm64_vm_exit) - 1); *((uint64_t*)(host_mem + ADDR_VAR_VMEXIT_PTR)) = ADDR_VAR_VMEXIT_CODE; text_prefix = kvm_asm64_init_vm; text_prefix_size = sizeof(kvm_asm64_init_vm) - 1; } else if (flags & KVM_SETUP_CPL3) { text_prefix = kvm_asm64_cpl3; text_prefix_size = sizeof(kvm_asm64_cpl3) - 1; } else { text_prefix = kvm_asm64_enable_long; text_prefix_size = sizeof(kvm_asm64_enable_long) - 1; } } struct tss16 tss16; memset(&tss16, 0, sizeof(tss16)); tss16.ss0 = tss16.ss1 = tss16.ss2 = SEL_DS16; tss16.sp0 = tss16.sp1 = tss16.sp2 = ADDR_STACK0; tss16.ip = ADDR_VAR_USER_CODE2; tss16.flags = (1 << 1); tss16.cs = SEL_CS16; tss16.es = tss16.ds = tss16.ss = SEL_DS16; tss16.ldt = SEL_LDT; struct tss16* tss16_addr = (struct tss16*)(host_mem + seg_tss16_2.base); memcpy(tss16_addr, &tss16, sizeof(tss16)); memset(&tss16, 0, sizeof(tss16)); tss16.ss0 = tss16.ss1 = tss16.ss2 = SEL_DS16; tss16.sp0 = tss16.sp1 = tss16.sp2 = ADDR_STACK0; tss16.ip = ADDR_VAR_USER_CODE2; tss16.flags = (1 << 1); tss16.cs = SEL_CS16_CPL3; tss16.es = tss16.ds = tss16.ss = SEL_DS16_CPL3; tss16.ldt = SEL_LDT; struct tss16* tss16_cpl3_addr = (struct tss16*)(host_mem + seg_tss16_cpl3.base); memcpy(tss16_cpl3_addr, &tss16, sizeof(tss16)); struct tss32 tss32; memset(&tss32, 0, sizeof(tss32)); tss32.ss0 = tss32.ss1 = tss32.ss2 = SEL_DS32; tss32.sp0 = tss32.sp1 = tss32.sp2 = ADDR_STACK0; tss32.ip = ADDR_VAR_USER_CODE; tss32.flags = (1 << 1) | (1 << 17); tss32.ldt = SEL_LDT; tss32.cr3 = sregs.cr3; tss32.io_bitmap = offsetof(struct tss32, io_bitmap); struct tss32* tss32_addr = (struct tss32*)(host_mem + seg_tss32_vm86.base); memcpy(tss32_addr, &tss32, sizeof(tss32)); memset(&tss32, 0, sizeof(tss32)); tss32.ss0 = tss32.ss1 = tss32.ss2 = SEL_DS32; tss32.sp0 = tss32.sp1 = tss32.sp2 = ADDR_STACK0; tss32.ip = ADDR_VAR_USER_CODE; tss32.flags = (1 << 1); tss32.cr3 = sregs.cr3; tss32.es = tss32.ds = tss32.ss = tss32.gs = tss32.fs = SEL_DS32; tss32.cs = SEL_CS32; tss32.ldt = SEL_LDT; tss32.cr3 = sregs.cr3; tss32.io_bitmap = offsetof(struct tss32, io_bitmap); struct tss32* tss32_cpl3_addr = (struct tss32*)(host_mem + seg_tss32_2.base); memcpy(tss32_cpl3_addr, &tss32, sizeof(tss32)); struct tss64 tss64; memset(&tss64, 0, sizeof(tss64)); tss64.rsp[0] = ADDR_STACK0; tss64.rsp[1] = ADDR_STACK0; tss64.rsp[2] = ADDR_STACK0; tss64.io_bitmap = offsetof(struct tss64, io_bitmap); struct tss64* tss64_addr = (struct tss64*)(host_mem + seg_tss64.base); memcpy(tss64_addr, &tss64, sizeof(tss64)); memset(&tss64, 0, sizeof(tss64)); tss64.rsp[0] = ADDR_STACK0; tss64.rsp[1] = ADDR_STACK0; tss64.rsp[2] = ADDR_STACK0; tss64.io_bitmap = offsetof(struct tss64, io_bitmap); struct tss64* tss64_cpl3_addr = (struct tss64*)(host_mem + seg_tss64_cpl3.base); memcpy(tss64_cpl3_addr, &tss64, sizeof(tss64)); if (text_size > 1000) text_size = 1000; if (text_prefix) { memcpy(host_text, text_prefix, text_prefix_size); void* patch = 0; patch = memmem(host_text, text_prefix_size, "\xde\xc0\xad\x0b", 4); if (patch) *((uint32_t*)patch) = guest_mem + ADDR_TEXT + ((char*)patch - host_text) + 6; uint16_t magic = PREFIX_SIZE; patch = 0; patch = memmem(host_text, text_prefix_size, &magic, sizeof(magic)); if (patch) *((uint16_t*)patch) = guest_mem + ADDR_TEXT + text_prefix_size; } memcpy((void*)(host_text + text_prefix_size), text, text_size); *(host_text + text_prefix_size + text_size) = 0xf4; memcpy(host_mem + ADDR_VAR_USER_CODE, text, text_size); *(host_mem + ADDR_VAR_USER_CODE + text_size) = 0xf4; *(host_mem + ADDR_VAR_HLT) = 0xf4; memcpy(host_mem + ADDR_VAR_SYSRET, "\x0f\x07\xf4", 3); memcpy(host_mem + ADDR_VAR_SYSEXIT, "\x0f\x35\xf4", 3); *(uint64_t*)(host_mem + ADDR_VAR_VMWRITE_FLD) = 0; *(uint64_t*)(host_mem + ADDR_VAR_VMWRITE_VAL) = 0; if (opt_count > 2) opt_count = 2; for (i = 0; i < opt_count; i++) { uint64_t typ = 0; uint64_t val = 0; typ = opt_array_ptr[i].typ; val = opt_array_ptr[i].val; switch (typ % 9) { case 0: sregs.cr0 ^= val & (CR0_MP | CR0_EM | CR0_ET | CR0_NE | CR0_WP | CR0_AM | CR0_NW | CR0_CD); break; case 1: sregs.cr4 ^= val & (CR4_VME | CR4_PVI | CR4_TSD | CR4_DE | CR4_MCE | CR4_PGE | CR4_PCE | CR4_OSFXSR | CR4_OSXMMEXCPT | CR4_UMIP | CR4_VMXE | CR4_SMXE | CR4_FSGSBASE | CR4_PCIDE | CR4_OSXSAVE | CR4_SMEP | CR4_SMAP | CR4_PKE); break; case 2: sregs.efer ^= val & (EFER_SCE | EFER_NXE | EFER_SVME | EFER_LMSLE | EFER_FFXSR | EFER_TCE); break; case 3: val &= ((1 << 8) | (1 << 9) | (1 << 10) | (1 << 12) | (1 << 13) | (1 << 14) | (1 << 15) | (1 << 18) | (1 << 19) | (1 << 20) | (1 << 21)); regs.rflags ^= val; tss16_addr->flags ^= val; tss16_cpl3_addr->flags ^= val; tss32_addr->flags ^= val; tss32_cpl3_addr->flags ^= val; break; case 4: seg_cs16.type = val & 0xf; seg_cs32.type = val & 0xf; seg_cs64.type = val & 0xf; break; case 5: seg_cs16_cpl3.type = val & 0xf; seg_cs32_cpl3.type = val & 0xf; seg_cs64_cpl3.type = val & 0xf; break; case 6: seg_ds16.type = val & 0xf; seg_ds32.type = val & 0xf; seg_ds64.type = val & 0xf; break; case 7: seg_ds16_cpl3.type = val & 0xf; seg_ds32_cpl3.type = val & 0xf; seg_ds64_cpl3.type = val & 0xf; break; case 8: *(uint64_t*)(host_mem + ADDR_VAR_VMWRITE_FLD) = (val & 0xffff); *(uint64_t*)(host_mem + ADDR_VAR_VMWRITE_VAL) = (val >> 16); break; default: fail("bad kvm setup opt"); } } regs.rflags |= 2; fill_segment_descriptor(gdt, ldt, &seg_ldt); fill_segment_descriptor(gdt, ldt, &seg_cs16); fill_segment_descriptor(gdt, ldt, &seg_ds16); fill_segment_descriptor(gdt, ldt, &seg_cs16_cpl3); fill_segment_descriptor(gdt, ldt, &seg_ds16_cpl3); fill_segment_descriptor(gdt, ldt, &seg_cs32); fill_segment_descriptor(gdt, ldt, &seg_ds32); fill_segment_descriptor(gdt, ldt, &seg_cs32_cpl3); fill_segment_descriptor(gdt, ldt, &seg_ds32_cpl3); fill_segment_descriptor(gdt, ldt, &seg_cs64); fill_segment_descriptor(gdt, ldt, &seg_ds64); fill_segment_descriptor(gdt, ldt, &seg_cs64_cpl3); fill_segment_descriptor(gdt, ldt, &seg_ds64_cpl3); fill_segment_descriptor(gdt, ldt, &seg_tss32); fill_segment_descriptor(gdt, ldt, &seg_tss32_2); fill_segment_descriptor(gdt, ldt, &seg_tss32_cpl3); fill_segment_descriptor(gdt, ldt, &seg_tss32_vm86); fill_segment_descriptor(gdt, ldt, &seg_tss16); fill_segment_descriptor(gdt, ldt, &seg_tss16_2); fill_segment_descriptor(gdt, ldt, &seg_tss16_cpl3); fill_segment_descriptor_dword(gdt, ldt, &seg_tss64); fill_segment_descriptor_dword(gdt, ldt, &seg_tss64_cpl3); fill_segment_descriptor(gdt, ldt, &seg_cgate16); fill_segment_descriptor(gdt, ldt, &seg_tgate16); fill_segment_descriptor(gdt, ldt, &seg_cgate32); fill_segment_descriptor(gdt, ldt, &seg_tgate32); fill_segment_descriptor_dword(gdt, ldt, &seg_cgate64); if (ioctl(cpufd, KVM_SET_SREGS, &sregs)) return -1; if (ioctl(cpufd, KVM_SET_REGS, ®s)) return -1; return 0; } static void loop(); static void sandbox_common() { prctl(PR_SET_PDEATHSIG, SIGKILL, 0, 0, 0); setpgrp(); setsid(); struct rlimit rlim; rlim.rlim_cur = rlim.rlim_max = 128 << 20; setrlimit(RLIMIT_AS, &rlim); rlim.rlim_cur = rlim.rlim_max = 8 << 20; setrlimit(RLIMIT_MEMLOCK, &rlim); rlim.rlim_cur = rlim.rlim_max = 1 << 20; setrlimit(RLIMIT_FSIZE, &rlim); rlim.rlim_cur = rlim.rlim_max = 1 << 20; setrlimit(RLIMIT_STACK, &rlim); rlim.rlim_cur = rlim.rlim_max = 0; setrlimit(RLIMIT_CORE, &rlim); #define CLONE_NEWCGROUP 0x02000000 unshare(CLONE_NEWNS); unshare(CLONE_NEWIPC); unshare(CLONE_NEWCGROUP); unshare(CLONE_NEWNET); unshare(CLONE_NEWUTS); unshare(CLONE_SYSVSEM); } static bool write_file(const char* file, const char* what, ...) { char buf[1024]; va_list args; va_start(args, what); vsnprintf(buf, sizeof(buf), what, args); va_end(args); buf[sizeof(buf) - 1] = 0; int len = strlen(buf); int fd = open(file, O_WRONLY | O_CLOEXEC); if (fd == -1) return false; if (write(fd, buf, len) != len) { close(fd); return false; } close(fd); return true; } static int real_uid; static int real_gid; __attribute__((aligned(64 << 10))) static char sandbox_stack[1 << 20]; static int namespace_sandbox_proc(void* arg) { sandbox_common(); write_file("/proc/self/setgroups", "deny"); if (!write_file("/proc/self/uid_map", "0 %d 1\n", real_uid)) fail("write of /proc/self/uid_map failed"); if (!write_file("/proc/self/gid_map", "0 %d 1\n", real_gid)) fail("write of /proc/self/gid_map failed"); if (mkdir("./syz-tmp", 0777)) fail("mkdir(syz-tmp) failed"); if (mount("", "./syz-tmp", "tmpfs", 0, NULL)) fail("mount(tmpfs) failed"); if (mkdir("./syz-tmp/newroot", 0777)) fail("mkdir failed"); if (mkdir("./syz-tmp/newroot/dev", 0700)) fail("mkdir failed"); if (mount("/dev", "./syz-tmp/newroot/dev", NULL, MS_BIND | MS_REC | MS_PRIVATE, NULL)) fail("mount(dev) failed"); if (mkdir("./syz-tmp/newroot/proc", 0700)) fail("mkdir failed"); if (mount(NULL, "./syz-tmp/newroot/proc", "proc", 0, NULL)) fail("mount(proc) failed"); if (mkdir("./syz-tmp/pivot", 0777)) fail("mkdir failed"); if (syscall(SYS_pivot_root, "./syz-tmp", "./syz-tmp/pivot")) { if (chdir("./syz-tmp")) fail("chdir failed"); } else { if (chdir("/")) fail("chdir failed"); if (umount2("./pivot", MNT_DETACH)) fail("umount failed"); } if (chroot("./newroot")) fail("chroot failed"); if (chdir("/")) fail("chdir failed"); struct __user_cap_header_struct cap_hdr = {}; struct __user_cap_data_struct cap_data[2] = {}; cap_hdr.version = _LINUX_CAPABILITY_VERSION_3; cap_hdr.pid = getpid(); if (syscall(SYS_capget, &cap_hdr, &cap_data)) fail("capget failed"); cap_data[0].effective &= ~(1 << CAP_SYS_PTRACE); cap_data[0].permitted &= ~(1 << CAP_SYS_PTRACE); cap_data[0].inheritable &= ~(1 << CAP_SYS_PTRACE); if (syscall(SYS_capset, &cap_hdr, &cap_data)) fail("capset failed"); loop(); doexit(1); } static int do_sandbox_namespace(int executor_pid, bool enable_tun) { int pid; real_uid = getuid(); real_gid = getgid(); mprotect(sandbox_stack, 4096, PROT_NONE); pid = clone(namespace_sandbox_proc, &sandbox_stack[sizeof(sandbox_stack) - 64], CLONE_NEWUSER | CLONE_NEWPID, NULL); if (pid < 0) fail("sandbox clone failed"); return pid; } struct thread_t { int created, running, call; pthread_t th; }; static struct thread_t threads[16]; static void execute_call(int call); static int running; static int collide; static void* thr(void* arg) { struct thread_t* th = (struct thread_t*)arg; for (;;) { while (!__atomic_load_n(&th->running, __ATOMIC_ACQUIRE)) syscall(SYS_futex, &th->running, FUTEX_WAIT, 0, 0); execute_call(th->call); __atomic_fetch_sub(&running, 1, __ATOMIC_RELAXED); __atomic_store_n(&th->running, 0, __ATOMIC_RELEASE); syscall(SYS_futex, &th->running, FUTEX_WAKE); } return 0; } static void execute(int num_calls) { int call, thread; running = 0; for (call = 0; call < num_calls; call++) { for (thread = 0; thread < sizeof(threads) / sizeof(threads[0]); thread++) { struct thread_t* th = &threads[thread]; if (!th->created) { th->created = 1; pthread_attr_t attr; pthread_attr_init(&attr); pthread_attr_setstacksize(&attr, 128 << 10); pthread_create(&th->th, &attr, thr, th); } if (!__atomic_load_n(&th->running, __ATOMIC_ACQUIRE)) { th->call = call; __atomic_fetch_add(&running, 1, __ATOMIC_RELAXED); __atomic_store_n(&th->running, 1, __ATOMIC_RELEASE); syscall(SYS_futex, &th->running, FUTEX_WAKE); if (collide && call % 2) break; struct timespec ts; ts.tv_sec = 0; ts.tv_nsec = 20 * 1000 * 1000; syscall(SYS_futex, &th->running, FUTEX_WAIT, 1, &ts); if (running) usleep((call == num_calls - 1) ? 10000 : 1000); break; } } } } long r[6]; void execute_call(int call) { switch (call) { case 0: syscall(__NR_mmap, 0x20000000, 0xfff000, 3, 0x32, -1, 0); break; case 1: syscall(__NR_mmap, 0x20000000, 0x1f000, 3, 0x32, -1, 0); break; case 2: memcpy((void*)0x2036a000, "./file0", 8); syscall(__NR_mkdir, 0x2036a000, 0); break; case 3: memcpy((void*)0x2000a000, "./file0", 8); memcpy((void*)0x20014ff8, "./file0", 8); memcpy((void*)0x20014000, "ramfs", 6); syscall(__NR_mount, 0x2000a000, 0x20014ff8, 0x20014000, 0x8408, 0x20005000); break; case 4: memcpy((void*)0x20012ff8, "./file0", 8); r[0] = syscall(__NR_openat, 0xffffff9c, 0x20012ff8, 0, 0); break; case 5: memcpy((void*)0x2001effd, "./file0/file0", 14); memcpy((void*)0x20012ff8, "./file0", 8); syscall(__NR_symlinkat, 0x2001effd, r[0], 0x20012ff8); break; case 6: memcpy((void*)0x20568000, "./file0/file0/bus", 18); syscall(__NR_creat, 0x20568000, -1); break; case 7: syscall(__NR_mmap, 0x2001f000, 0x1000, 3, 0x32, -1, 0); break; case 8: memcpy((void*)0x20014000, "./file0/file0/bus", 18); memcpy((void*)0x2001f000, "./file0/file0", 14); syscall(__NR_renameat, r[0], 0x20014000, r[0], 0x2001f000); break; case 9: memcpy((void*)0x20017ff8, "./file0", 8); syscall(__NR_faccessat, r[0], 0x20017ff8, 1, 0); break; case 10: memcpy((void*)0x203f9000, "/dev/kvm", 9); r[1] = syscall(__NR_openat, 0xffffffffffffff9c, 0x203f9000, 0, 0); break; case 11: r[2] = syscall(__NR_ioctl, r[1], 0xae01, 0); break; case 12: *(uint64_t*)0x205ec000 = 0x10; *(uint64_t*)0x205ec008 = 0x20e53fa5; *(uint64_t*)0x205ec010 = 0x5b; memcpy((void*)0x20e53fa5, "\x0f\x01\xcf\x0f\x20\xe0\x66\x35\x04\x00\x00\x00\x0f\x22\xe0\x66" "\xb8\x05\xef\x46\x7d\x0f\x23\xc8\x0f\x21\xf8\x66\x35\x0c\x00\xf0" "\x00\x0f\x23\xf8\x64\x0f\x20\x9c\x0f\x18\x78\xa5\xd9\xf4\x8f\xc9" "\x50\x01\xfe\x0f\x07\x67\x66\xc7\x44\x24\x00\x01\x00\x00\x00\x67" "\x66\xc7\x44\x24\x02\x34\xac\x00\x00\x67\x66\xc7\x44\x24\x06\x00" "\x00\x00\x00\x67\x0f\x01\x1c\x24\x0f\xf5\x14", 91); syz_kvm_setup_cpu(r[2], -1, 0x2077c000, 0x205ec000, 1, 0, 0x20823ff0, 0); break; case 13: r[3] = syscall(__NR_ioctl, r[2], 0xae41, 0); break; case 14: *(uint32_t*)0x20583fb8 = 1; *(uint32_t*)0x20583fbc = 0; *(uint32_t*)0x20583fc0 = 0x40000021; *(uint32_t*)0x20583fc4 = 0; *(uint64_t*)0x20583fc8 = 9; syscall(__NR_ioctl, r[3], 0x4008ae89, 0x20583fb8); break; case 15: syscall(__NR_ioctl, r[3], 0xae80, 0); break; case 16: memcpy((void*)0x2048afef, "/selinux/enforce", 17); r[4] = syscall(__NR_openat, 0xffffffffffffff9c, 0x2048afef, 0x18000, 0); break; case 17: syscall(__NR_setsockopt, r[4], 6, 0x1f, 0x20590000, 0); break; case 18: memcpy((void*)0x20386000, "user", 5); *(uint8_t*)0x207faffb = 0x73; *(uint8_t*)0x207faffc = 0x79; *(uint8_t*)0x207faffd = 0x7a; *(uint8_t*)0x207faffe = 0x22; *(uint8_t*)0x207fafff = 0; memcpy((void*)0x20f29000, "\xfa\xc3\x7f\xc1\xdb\x92\x95\xc5\xb5\xdf\xd6\xe3\xbb\x0f\x65\xa0" "\x62\x93\x71\xeb\x80\x67\x2f\xc9\xb6\x60\xd0\xcf\xe7\x4c\x43\x0a" "\xca\xf8\x7f\x41\x7a\x8b\xdc\x7d\x73\xbb\x4b\x41\x8a\xa7\x83\x3e" "\xfd\xc1\x91\x9d\x8a\x8a\x69\x4a\xc1\x61\x59\xd5\xe5\x61\x64\x44" "\xaf\xb4\x0b\xe6\x71\x63\x01\x18\x60\x4b\x53\x6e\xe1\x3c\x85\x67" "\x01\x70\x99\x19\xf5\xbc\x0b\x52\x3c\x02\x92\x07\x5f\x4a\x68\x50" "\x83\x68\xe3\xd0\x2e\xbf\x37\xe3\x64\xf6\x26\x1a\x78\xfc\x81\x3d" "\x9e\xdd\x61\x4c\x42\x95\x85\xf9\x97\x31\xf7\x37\xf9\xa7\x1c\x76" "\x7b\x3f\xf3", 131); syscall(__NR_add_key, 0x20386000, 0x207faffb, 0x20f29000, 0x83, 0xfffffffc); break; case 19: *(uint32_t*)0x20021ffc = 0xe8; syscall(__NR_getsockopt, r[4], 0x29, 0x22, 0x20f26f18, 0x20021ffc); break; case 20: syscall(__NR_getresgid, 0x203d6000, 0x200f4000, 0x2063bffc); break; case 21: syscall(__NR_ptrace, 3, 0, 1); break; case 22: *(uint32_t*)0x20a69000 = 0x3f; syscall(__NR_ioctl, r[2], 0xc004aea7, 0x20a69000); break; case 23: *(uint32_t*)0x201cdffc = 9; syscall(__NR_ioctl, r[4], 0x400454cb, 0x201cdffc); break; case 24: memcpy((void*)0x20ba5000, "big_key", 8); *(uint8_t*)0x20eda000 = 0x73; *(uint8_t*)0x20eda001 = 0x79; *(uint8_t*)0x20eda002 = 0x7a; *(uint8_t*)0x20eda003 = 0x23; *(uint8_t*)0x20eda004 = 0; memcpy((void*)0x2068bf26, "\x95\x6c\x99\x95\x3c\x45\xe4\xab\x81\xe5\x48\x11\x14\x1b\x1c\x93" "\xc7\x5c\x56\xf4\xd3\x00\xe2\x21\x6e\x29\xa1\x1b\xab\x63\xe5\x59" "\xb2\xc1\xf7\xe5\xea\x8e\x5b\xc3\x26\xa9\x11\xbb\x6d\xbf\x16\x09" "\xb8\x62\x15\x21\x35\xfa\x43\x6b\x9f\x1c\x15\x4c\xd3\x86\xba\xcc" "\x81\x52\xad\x61\x15\xad\x4e\x93\x56\xa8\x8a\xb9\xc5\x47\x09\x6b" "\xb7\xc9\x06\xce\xa6\x24\x80\x6a\xa0\x17\x08\xec\x93\xe1\xef\xe5" "\x85\xe3\x92\x78\x5c\x3c\xa0\x50\xf0\xc9\x66\x13\x0b\xca\x7c\x78" "\x57\xce\xa9\x52\x48\x14\x08\x5d\xd0\xc8\x2c\xe2\xd8\x74\x4c\xe2" "\x72\x39\xd4\x73\x4e\x11\x94\x71\xab\x44\x54\x72\xe2\xd1\x59\x1c" "\x23\x4c\xf9\x52\xb3\xc1\x6c\xb0\xb2\xc5\x58\x03\x75\x4d\x82\x14" "\x86\xf6\x6f\xaa\xdc\x9a\xe9\xc2\x07\x31\x76\x57\x21\x38\x0a\x1d" "\xc1\xe9\x70\xa5\xcb\x3a\xac\xcf\x70\x06\x2b\x7d\xfb\x20\xeb\xed" "\xf9\x77\x9f\x1b\xb5\xe4\x8a\xdf\x49\x72\xde\xb6\x64\x41\x16\xc2" "\x46\x33\x1d\x84\x3c\xb2\xa6\x74\x75\x82", 218); r[5] = syscall(__NR_add_key, 0x20ba5000, 0x20eda000, 0x2068bf26, 0xda, 0xfffffff9); break; case 25: *(uint64_t*)0x2059f000 = 8; *(uint64_t*)0x2059f008 = 0x20ed1000; *(uint64_t*)0x2059f010 = 0x4f; memcpy((void*)0x20ed1000, "\xf0\x0f\xab\x13\x44\x0f\x20\xc0\x66\x35\x05\x00\x00\x00\x44\x0f" "\x22\xc0\x0f\x08\x66\xd9\xea\xba\xf8\x0c\x66\xb8\xbc\xb5\xb8\x82" "\x66\xef\xba\xfc\x0c\x66\xb8\x00\x70\x00\x00\x66\xef\xba\xd1\x04" "\x66\xed\xba\xf8\x0c\x66\xb8\xa6\x63\x87\x82\x66\xef\xba\xfc\x0c" "\xb8\x11\x00\xef\x0f\xa3\xd5\xf2\x0f\x79\xfa\x0f\x71\xd5\xde", 79); syz_kvm_setup_cpu(r[4], r[4], 0x20454000, 0x2059f000, 1, 0x79, 0x2045f000, 0); break; case 26: syscall(__NR_keyctl, 0xf, r[5], 0x74); break; case 27: *(uint64_t*)0x20f25000 = 0xff; *(uint64_t*)0x20f25008 = 0x7fff; syscall(__NR_ioctl, r[4], 0x4010aeab, 0x20f25000); break; } } void loop() { memset(r, -1, sizeof(r)); execute(28); collide = 1; execute(28); } int main() { use_temporary_dir(); int pid = do_sandbox_namespace(0, false); int status = 0; while (waitpid(pid, &status, __WALL) != pid) { } return 0; }