From c97c626aa944959e3875e3e1c59874c39f6eb776 Mon Sep 17 00:00:00 2001 From: Sandipan Das Date: Thu, 7 Jun 2018 20:07:02 +0530 Subject: [PATCH] arch-power: Fix stack layout for 64-bit execution This fixes the call stack layout by changing the size of the auxiliary vector entries, each of which contain two 64-bit values. Also, all base addresses for stack contents are now considered to be 64 bits in order to prevent underflows during program execution. Users can now run statically-linked 64-bit ELF ABI v2 compliant PowerPC LSB ELF executables in syscall emulation mode. Change-Id: I256399d9344b1b101385e32ad8978325aec9844e Signed-off-by: Sandipan Das --- src/arch/power/isa_traits.hh | 2 +- src/arch/power/process.cc | 57 +++++++++++++++++++++++++++--------- 2 files changed, 44 insertions(+), 15 deletions(-) diff --git a/src/arch/power/isa_traits.hh b/src/arch/power/isa_traits.hh index 99f76ffad..4f84ac34f 100644 --- a/src/arch/power/isa_traits.hh +++ b/src/arch/power/isa_traits.hh @@ -58,7 +58,7 @@ const Addr NPtePageShift = PageShift - PteShift; const Addr NPtePage = ULL(1) << NPtePageShift; const Addr PteMask = NPtePage - 1; -const int MachineBytes = 4; +const int MachineBytes = 8; // Memory accesses can be unaligned const bool HasUnalignedMemAcc = true; diff --git a/src/arch/power/process.cc b/src/arch/power/process.cc index 6561bff4e..fccf84907 100644 --- a/src/arch/power/process.cc +++ b/src/arch/power/process.cc @@ -85,7 +85,7 @@ PowerProcess::initState() void PowerProcess::argsInit(int intSize, int pageSize) { - typedef AuxVector auxv_t; + typedef AuxVector auxv_t; std::vector auxv; string filename; @@ -103,11 +103,37 @@ PowerProcess::argsInit(int intSize, int pageSize) // load object file into target memory objFile->loadSections(initVirtMem); + enum PowerCpuFeature { + Power_32 = ULL(1) << 31, // Always set for powerpc64 + Power_64 = ULL(1) << 30, // Always set for powerpc64 + Power_HAS_ALTIVEC = ULL(1) << 28, + Power_HAS_FPU = ULL(1) << 27, + Power_HAS_MMU = ULL(1) << 26, + Power_UNIFIED_CACHE = ULL(1) << 24, + Power_NO_TB = ULL(1) << 20, // 601/403gx have no timebase + Power_POWER4 = ULL(1) << 19, // POWER4 ISA 2.00 + Power_POWER5 = ULL(1) << 18, // POWER5 ISA 2.02 + Power_POWER5_PLUS = ULL(1) << 17, // POWER5+ ISA 2.03 + Power_CELL_BE = ULL(1) << 16, // CELL Broadband Engine + Power_BOOKE = ULL(1) << 15, // ISA Category Embedded + Power_SMT = ULL(1) << 14, // Simultaneous Multi-Threading + Power_ICACHE_SNOOP = ULL(1) << 13, + Power_ARCH_2_05 = ULL(1) << 12, // ISA 2.05 + Power_PA6T = ULL(1) << 11, // PA Semi 6T Core + Power_HAS_DFP = ULL(1) << 10, // Decimal FP Unit + Power_POWER6_EXT = ULL(1) << 9, // P6 + mffgpr/mftgpr + Power_ARCH_2_06 = ULL(1) << 8, // ISA 2.06 + Power_HAS_VSX = ULL(1) << 7, // P7 Vector Extension + Power_PSERIES_PERFMON_COMPAT = ULL(1) << 6, + Power_TRUE_LE = ULL(1) << 1, + Power_PPC_LE = ULL(1) << 0 + }; + //Setup the auxilliary vectors. These will already have endian conversion. //Auxilliary vectors are loaded only for elf formatted executables. ElfObject * elfObject = dynamic_cast(objFile); if (elfObject) { - uint32_t features = 0; + uint64_t features = Power_32 | Power_64 | Power_PPC_LE; //Bits which describe the system hardware capabilities //XXX Figure out what these should be @@ -142,6 +168,9 @@ PowerProcess::argsInit(int intSize, int pageSize) auxv.push_back(auxv_t(M5_AT_EXECFN, 0)); //The string "v51" with unknown meaning auxv.push_back(auxv_t(M5_AT_PLATFORM, 0)); + //The address of 16 bytes in the data section containing a random + //value; it is required for stack protection using a canary value. + auxv.push_back(auxv_t(M5_AT_RANDOM, objFile->dataBase())); } //Figure out how big the initial stack nedes to be @@ -205,15 +234,15 @@ PowerProcess::argsInit(int intSize, int pageSize) roundUp(memState->getStackSize(), pageSize)); // map out initial stack contents - uint32_t sentry_base = memState->getStackBase() - sentry_size; - uint32_t aux_data_base = sentry_base - aux_data_size; - uint32_t env_data_base = aux_data_base - env_data_size; - uint32_t arg_data_base = env_data_base - arg_data_size; - uint32_t platform_base = arg_data_base - platform_size; - uint32_t auxv_array_base = platform_base - aux_array_size - aux_padding; - uint32_t envp_array_base = auxv_array_base - envp_array_size; - uint32_t argv_array_base = envp_array_base - argv_array_size; - uint32_t argc_base = argv_array_base - argc_size; + uint64_t sentry_base = memState->getStackBase() - sentry_size; + uint64_t aux_data_base = sentry_base - aux_data_size; + uint64_t env_data_base = aux_data_base - env_data_size; + uint64_t arg_data_base = env_data_base - arg_data_size; + uint64_t platform_base = arg_data_base - platform_size; + uint64_t auxv_array_base = platform_base - aux_array_size - aux_padding; + uint64_t envp_array_base = auxv_array_base - envp_array_size; + uint64_t argv_array_base = envp_array_base - argv_array_size; + uint64_t argc_base = argv_array_base - argc_size; DPRINTF(Stack, "The addresses of items on the initial stack:\n"); DPRINTF(Stack, "0x%x - aux data\n", aux_data_base); @@ -229,11 +258,11 @@ PowerProcess::argsInit(int intSize, int pageSize) // write contents to stack // figure out argc - uint32_t argc = argv.size(); - uint32_t guestArgc = PowerISA::htog(argc); + uint64_t argc = argv.size(); + uint64_t guestArgc = PowerISA::htog(argc); //Write out the sentry void * - uint32_t sentry_NULL = 0; + uint64_t sentry_NULL = 0; initVirtMem.writeBlob(sentry_base, (uint8_t*)&sentry_NULL, sentry_size); -- 2.30.2