diff options
Diffstat (limited to 'arch/powerpc/kernel')
| -rw-r--r-- | arch/powerpc/kernel/Makefile | 1 | ||||
| -rw-r--r-- | arch/powerpc/kernel/asm-offsets.c | 3 | ||||
| -rw-r--r-- | arch/powerpc/kernel/entry_32.S | 10 | ||||
| -rw-r--r-- | arch/powerpc/kernel/entry_64.S | 69 | ||||
| -rw-r--r-- | arch/powerpc/kernel/exceptions-64e.S | 27 | ||||
| -rw-r--r-- | arch/powerpc/kernel/exceptions-64s.S | 98 | ||||
| -rw-r--r-- | arch/powerpc/kernel/head_booke.h | 12 | ||||
| -rw-r--r-- | arch/powerpc/kernel/head_fsl_booke.S | 15 | ||||
| -rw-r--r-- | arch/powerpc/kernel/module.c | 10 | ||||
| -rw-r--r-- | arch/powerpc/kernel/security.c | 434 | ||||
| -rw-r--r-- | arch/powerpc/kernel/setup_32.c | 3 | ||||
| -rw-r--r-- | arch/powerpc/kernel/setup_64.c | 51 | ||||
| -rw-r--r-- | arch/powerpc/kernel/vmlinux.lds.S | 33 |
13 files changed, 690 insertions, 76 deletions
diff --git a/arch/powerpc/kernel/Makefile b/arch/powerpc/kernel/Makefile index ba336930d448..22ed3c32fca8 100644 --- a/arch/powerpc/kernel/Makefile +++ b/arch/powerpc/kernel/Makefile @@ -44,6 +44,7 @@ obj-$(CONFIG_PPC_BOOK3S_64) += cpu_setup_power.o obj-$(CONFIG_PPC_BOOK3S_64) += mce.o mce_power.o obj64-$(CONFIG_RELOCATABLE) += reloc_64.o obj-$(CONFIG_PPC_BOOK3E_64) += exceptions-64e.o idle_book3e.o +obj-$(CONFIG_PPC_BARRIER_NOSPEC) += security.o obj-$(CONFIG_PPC64) += vdso64/ obj-$(CONFIG_ALTIVEC) += vecemu.o obj-$(CONFIG_PPC_970_NAP) += idle_power4.o diff --git a/arch/powerpc/kernel/asm-offsets.c b/arch/powerpc/kernel/asm-offsets.c index d92705e3a0c1..de3c29c51503 100644 --- a/arch/powerpc/kernel/asm-offsets.c +++ b/arch/powerpc/kernel/asm-offsets.c @@ -245,8 +245,7 @@ int main(void) DEFINE(PACA_IN_MCE, offsetof(struct paca_struct, in_mce)); DEFINE(PACA_RFI_FLUSH_FALLBACK_AREA, offsetof(struct paca_struct, rfi_flush_fallback_area)); DEFINE(PACA_EXRFI, offsetof(struct paca_struct, exrfi)); - DEFINE(PACA_L1D_FLUSH_CONGRUENCE, offsetof(struct paca_struct, l1d_flush_congruence)); - DEFINE(PACA_L1D_FLUSH_SETS, offsetof(struct paca_struct, l1d_flush_sets)); + DEFINE(PACA_L1D_FLUSH_SIZE, offsetof(struct paca_struct, l1d_flush_size)); #endif DEFINE(PACAHWCPUID, offsetof(struct paca_struct, hw_cpu_id)); DEFINE(PACAKEXECSTATE, offsetof(struct paca_struct, kexec_state)); diff --git a/arch/powerpc/kernel/entry_32.S b/arch/powerpc/kernel/entry_32.S index 3728e617e17e..609bc7d01f13 100644 --- a/arch/powerpc/kernel/entry_32.S +++ b/arch/powerpc/kernel/entry_32.S @@ -33,6 +33,7 @@ #include <asm/unistd.h> #include <asm/ftrace.h> #include <asm/ptrace.h> +#include <asm/barrier.h> /* * MSR_KERNEL is > 0x10000 on 4xx/Book-E since it include MSR_CE. @@ -340,6 +341,15 @@ syscall_dotrace_cont: ori r10,r10,sys_call_table@l slwi r0,r0,2 bge- 66f + + barrier_nospec_asm + /* + * Prevent the load of the handler below (based on the user-passed + * system call number) being speculatively executed until the test + * against NR_syscalls and branch to .66f above has + * committed. + */ + lwzx r10,r10,r0 /* Fetch system call handler [ptr] */ mtlr r10 addi r9,r1,STACK_FRAME_OVERHEAD diff --git a/arch/powerpc/kernel/entry_64.S b/arch/powerpc/kernel/entry_64.S index 59be96917369..6d36a4fb4acf 100644 --- a/arch/powerpc/kernel/entry_64.S +++ b/arch/powerpc/kernel/entry_64.S @@ -25,6 +25,7 @@ #include <asm/page.h> #include <asm/mmu.h> #include <asm/thread_info.h> +#include <asm/code-patching-asm.h> #include <asm/ppc_asm.h> #include <asm/asm-offsets.h> #include <asm/cputable.h> @@ -36,6 +37,7 @@ #include <asm/hw_irq.h> #include <asm/context_tracking.h> #include <asm/tm.h> +#include <asm/barrier.h> #ifdef CONFIG_PPC_BOOK3S #include <asm/exception-64s.h> #else @@ -75,6 +77,11 @@ END_FTR_SECTION_IFSET(CPU_FTR_TM) std r0,GPR0(r1) std r10,GPR1(r1) beq 2f /* if from kernel mode */ +#ifdef CONFIG_PPC_FSL_BOOK3E +START_BTB_FLUSH_SECTION + BTB_FLUSH(r10) +END_BTB_FLUSH_SECTION +#endif ACCOUNT_CPU_USER_ENTRY(r10, r11) 2: std r2,GPR2(r1) std r3,GPR3(r1) @@ -177,6 +184,15 @@ system_call: /* label this so stack traces look sane */ clrldi r8,r8,32 15: slwi r0,r0,4 + + barrier_nospec_asm + /* + * Prevent the load of the handler below (based on the user-passed + * system call number) being speculatively executed until the test + * against NR_syscalls and branch to .Lsyscall_enosys above has + * committed. + */ + ldx r12,r11,r0 /* Fetch system call handler [ptr] */ mtctr r12 bctrl /* Call handler */ @@ -440,6 +456,57 @@ _GLOBAL(ret_from_kernel_thread) li r3,0 b .Lsyscall_exit +#ifdef CONFIG_PPC_BOOK3S_64 + +#define FLUSH_COUNT_CACHE \ +1: nop; \ + patch_site 1b, patch__call_flush_count_cache + + +#define BCCTR_FLUSH .long 0x4c400420 + +.macro nops number + .rept \number + nop + .endr +.endm + +.balign 32 +.global flush_count_cache +flush_count_cache: + /* Save LR into r9 */ + mflr r9 + + .rept 64 + bl .+4 + .endr + b 1f + nops 6 + + .balign 32 + /* Restore LR */ +1: mtlr r9 + li r9,0x7fff + mtctr r9 + + BCCTR_FLUSH + +2: nop + patch_site 2b patch__flush_count_cache_return + + nops 3 + + .rept 278 + .balign 32 + BCCTR_FLUSH + nops 7 + .endr + + blr +#else +#define FLUSH_COUNT_CACHE +#endif /* CONFIG_PPC_BOOK3S_64 */ + /* * This routine switches between two different tasks. The process * state of one is saved on its kernel stack. Then the state @@ -503,6 +570,8 @@ BEGIN_FTR_SECTION END_FTR_SECTION_IFSET(CPU_FTR_ARCH_207S) #endif + FLUSH_COUNT_CACHE + #ifdef CONFIG_SMP /* We need a sync somewhere here to make sure that if the * previous task gets rescheduled on another CPU, it sees all diff --git a/arch/powerpc/kernel/exceptions-64e.S b/arch/powerpc/kernel/exceptions-64e.S index 5cc93f0b52ca..48ec841ea1bf 100644 --- a/arch/powerpc/kernel/exceptions-64e.S +++ b/arch/powerpc/kernel/exceptions-64e.S @@ -295,7 +295,8 @@ ret_from_mc_except: andi. r10,r11,MSR_PR; /* save stack pointer */ \ beq 1f; /* branch around if supervisor */ \ ld r1,PACAKSAVE(r13); /* get kernel stack coming from usr */\ -1: cmpdi cr1,r1,0; /* check if SP makes sense */ \ +1: type##_BTB_FLUSH \ + cmpdi cr1,r1,0; /* check if SP makes sense */ \ bge- cr1,exc_##n##_bad_stack;/* bad stack (TODO: out of line) */ \ mfspr r10,SPRN_##type##_SRR0; /* read SRR0 before touching stack */ @@ -327,6 +328,30 @@ ret_from_mc_except: #define SPRN_MC_SRR0 SPRN_MCSRR0 #define SPRN_MC_SRR1 SPRN_MCSRR1 +#ifdef CONFIG_PPC_FSL_BOOK3E +#define GEN_BTB_FLUSH \ + START_BTB_FLUSH_SECTION \ + beq 1f; \ + BTB_FLUSH(r10) \ + 1: \ + END_BTB_FLUSH_SECTION + +#define CRIT_BTB_FLUSH \ + START_BTB_FLUSH_SECTION \ + BTB_FLUSH(r10) \ + END_BTB_FLUSH_SECTION + +#define DBG_BTB_FLUSH CRIT_BTB_FLUSH +#define MC_BTB_FLUSH CRIT_BTB_FLUSH +#define GDBELL_BTB_FLUSH GEN_BTB_FLUSH +#else +#define GEN_BTB_FLUSH +#define CRIT_BTB_FLUSH +#define DBG_BTB_FLUSH +#define MC_BTB_FLUSH +#define GDBELL_BTB_FLUSH +#endif + #define NORMAL_EXCEPTION_PROLOG(n, intnum, addition) \ EXCEPTION_PROLOG(n, intnum, GEN, addition##_GEN(n)) diff --git a/arch/powerpc/kernel/exceptions-64s.S b/arch/powerpc/kernel/exceptions-64s.S index 938a30fef031..10e7cec9553d 100644 --- a/arch/powerpc/kernel/exceptions-64s.S +++ b/arch/powerpc/kernel/exceptions-64s.S @@ -36,6 +36,7 @@ BEGIN_FTR_SECTION \ END_FTR_SECTION_IFSET(CPU_FTR_REAL_LE) \ mr r9,r13 ; \ GET_PACA(r13) ; \ + INTERRUPT_TO_KERNEL ; \ mfspr r11,SPRN_SRR0 ; \ 0: @@ -292,7 +293,9 @@ hardware_interrupt_hv: . = 0x900 .globl decrementer_pSeries decrementer_pSeries: - _MASKABLE_EXCEPTION_PSERIES(0x900, decrementer, EXC_STD, SOFTEN_TEST_PR) + SET_SCRATCH0(r13) + EXCEPTION_PROLOG_0(PACA_EXGEN) + b decrementer_ool STD_EXCEPTION_HV(0x980, 0x982, hdecrementer) @@ -319,6 +322,7 @@ system_call_pSeries: OPT_GET_SPR(r9, SPRN_PPR, CPU_FTR_HAS_PPR); HMT_MEDIUM; std r10,PACA_EXGEN+EX_R10(r13) + INTERRUPT_TO_KERNEL OPT_SAVE_REG_TO_PACA(PACA_EXGEN+EX_PPR, r9, CPU_FTR_HAS_PPR); mfcr r9 KVMTEST(0xc00) @@ -607,6 +611,7 @@ END_FTR_SECTION_IFSET(CPU_FTR_CFAR) .align 7 /* moved from 0xe00 */ + MASKABLE_EXCEPTION_OOL(0x900, decrementer) STD_EXCEPTION_HV_OOL(0xe02, h_data_storage) KVM_HANDLER_SKIP(PACA_EXGEN, EXC_HV, 0xe02) STD_EXCEPTION_HV_OOL(0xe22, h_instr_storage) @@ -1564,6 +1569,21 @@ power4_fixup_nap: blr #endif + .balign 16 + .globl stf_barrier_fallback +stf_barrier_fallback: + std r9,PACA_EXRFI+EX_R9(r13) + std r10,PACA_EXRFI+EX_R10(r13) + sync + ld r9,PACA_EXRFI+EX_R9(r13) + ld r10,PACA_EXRFI+EX_R10(r13) + ori 31,31,0 + .rept 14 + b 1f +1: + .endr + blr + .globl rfi_flush_fallback rfi_flush_fallback: SET_SCRATCH0(r13); @@ -1571,39 +1591,37 @@ rfi_flush_fallback: std r9,PACA_EXRFI+EX_R9(r13) std r10,PACA_EXRFI+EX_R10(r13) std r11,PACA_EXRFI+EX_R11(r13) - std r12,PACA_EXRFI+EX_R12(r13) - std r8,PACA_EXRFI+EX_R13(r13) mfctr r9 ld r10,PACA_RFI_FLUSH_FALLBACK_AREA(r13) - ld r11,PACA_L1D_FLUSH_SETS(r13) - ld r12,PACA_L1D_FLUSH_CONGRUENCE(r13) - /* - * The load adresses are at staggered offsets within cachelines, - * which suits some pipelines better (on others it should not - * hurt). - */ - addi r12,r12,8 + ld r11,PACA_L1D_FLUSH_SIZE(r13) + srdi r11,r11,(7 + 3) /* 128 byte lines, unrolled 8x */ mtctr r11 DCBT_STOP_ALL_STREAM_IDS(r11) /* Stop prefetch streams */ /* order ld/st prior to dcbt stop all streams with flushing */ sync -1: li r8,0 - .rept 8 /* 8-way set associative */ - ldx r11,r10,r8 - add r8,r8,r12 - xor r11,r11,r11 // Ensure r11 is 0 even if fallback area is not - add r8,r8,r11 // Add 0, this creates a dependency on the ldx - .endr - addi r10,r10,128 /* 128 byte cache line */ + + /* + * The load adresses are at staggered offsets within cachelines, + * which suits some pipelines better (on others it should not + * hurt). + */ +1: + ld r11,(0x80 + 8)*0(r10) + ld r11,(0x80 + 8)*1(r10) + ld r11,(0x80 + 8)*2(r10) + ld r11,(0x80 + 8)*3(r10) + ld r11,(0x80 + 8)*4(r10) + ld r11,(0x80 + 8)*5(r10) + ld r11,(0x80 + 8)*6(r10) + ld r11,(0x80 + 8)*7(r10) + addi r10,r10,0x80*8 bdnz 1b mtctr r9 ld r9,PACA_EXRFI+EX_R9(r13) ld r10,PACA_EXRFI+EX_R10(r13) ld r11,PACA_EXRFI+EX_R11(r13) - ld r12,PACA_EXRFI+EX_R12(r13) - ld r8,PACA_EXRFI+EX_R13(r13) GET_SCRATCH0(r13); rfid @@ -1614,39 +1632,37 @@ hrfi_flush_fallback: std r9,PACA_EXRFI+EX_R9(r13) std r10,PACA_EXRFI+EX_R10(r13) std r11,PACA_EXRFI+EX_R11(r13) - std r12,PACA_EXRFI+EX_R12(r13) - std r8,PACA_EXRFI+EX_R13(r13) mfctr r9 ld r10,PACA_RFI_FLUSH_FALLBACK_AREA(r13) - ld r11,PACA_L1D_FLUSH_SETS(r13) - ld r12,PACA_L1D_FLUSH_CONGRUENCE(r13) - /* - * The load adresses are at staggered offsets within cachelines, - * which suits some pipelines better (on others it should not - * hurt). - */ - addi r12,r12,8 + ld r11,PACA_L1D_FLUSH_SIZE(r13) + srdi r11,r11,(7 + 3) /* 128 byte lines, unrolled 8x */ mtctr r11 DCBT_STOP_ALL_STREAM_IDS(r11) /* Stop prefetch streams */ /* order ld/st prior to dcbt stop all streams with flushing */ sync -1: li r8,0 - .rept 8 /* 8-way set associative */ - ldx r11,r10,r8 - add r8,r8,r12 - xor r11,r11,r11 // Ensure r11 is 0 even if fallback area is not - add r8,r8,r11 // Add 0, this creates a dependency on the ldx - .endr - addi r10,r10,128 /* 128 byte cache line */ + + /* + * The load adresses are at staggered offsets within cachelines, + * which suits some pipelines better (on others it should not + * hurt). + */ +1: + ld r11,(0x80 + 8)*0(r10) + ld r11,(0x80 + 8)*1(r10) + ld r11,(0x80 + 8)*2(r10) + ld r11,(0x80 + 8)*3(r10) + ld r11,(0x80 + 8)*4(r10) + ld r11,(0x80 + 8)*5(r10) + ld r11,(0x80 + 8)*6(r10) + ld r11,(0x80 + 8)*7(r10) + addi r10,r10,0x80*8 bdnz 1b mtctr r9 ld r9,PACA_EXRFI+EX_R9(r13) ld r10,PACA_EXRFI+EX_R10(r13) ld r11,PACA_EXRFI+EX_R11(r13) - ld r12,PACA_EXRFI+EX_R12(r13) - ld r8,PACA_EXRFI+EX_R13(r13) GET_SCRATCH0(r13); hrfid diff --git a/arch/powerpc/kernel/head_booke.h b/arch/powerpc/kernel/head_booke.h index a620203f7de3..7b98c7351f6c 100644 --- a/arch/powerpc/kernel/head_booke.h +++ b/arch/powerpc/kernel/head_booke.h @@ -31,6 +31,16 @@ */ #define THREAD_NORMSAVE(offset) (THREAD_NORMSAVES + (offset * 4)) +#ifdef CONFIG_PPC_FSL_BOOK3E +#define BOOKE_CLEAR_BTB(reg) \ +START_BTB_FLUSH_SECTION \ + BTB_FLUSH(reg) \ +END_BTB_FLUSH_SECTION +#else +#define BOOKE_CLEAR_BTB(reg) +#endif + + #define NORMAL_EXCEPTION_PROLOG(intno) \ mtspr SPRN_SPRG_WSCRATCH0, r10; /* save one register */ \ mfspr r10, SPRN_SPRG_THREAD; \ @@ -42,6 +52,7 @@ andi. r11, r11, MSR_PR; /* check whether user or kernel */\ mr r11, r1; \ beq 1f; \ + BOOKE_CLEAR_BTB(r11) \ /* if from user, start at top of this thread's kernel stack */ \ lwz r11, THREAD_INFO-THREAD(r10); \ ALLOC_STACK_FRAME(r11, THREAD_SIZE); \ @@ -127,6 +138,7 @@ stw r9,_CCR(r8); /* save CR on stack */\ mfspr r11,exc_level_srr1; /* check whether user or kernel */\ DO_KVM BOOKE_INTERRUPT_##intno exc_level_srr1; \ + BOOKE_CLEAR_BTB(r10) \ andi. r11,r11,MSR_PR; \ mfspr r11,SPRN_SPRG_THREAD; /* if from user, start at top of */\ lwz r11,THREAD_INFO-THREAD(r11); /* this thread's kernel stack */\ diff --git a/arch/powerpc/kernel/head_fsl_booke.S b/arch/powerpc/kernel/head_fsl_booke.S index fffd1f96bb1d..275769b6fb0d 100644 --- a/arch/powerpc/kernel/head_fsl_booke.S +++ b/arch/powerpc/kernel/head_fsl_booke.S @@ -451,6 +451,13 @@ END_FTR_SECTION_IFSET(CPU_FTR_EMB_HV) mfcr r13 stw r13, THREAD_NORMSAVE(3)(r10) DO_KVM BOOKE_INTERRUPT_DTLB_MISS SPRN_SRR1 +START_BTB_FLUSH_SECTION + mfspr r11, SPRN_SRR1 + andi. r10,r11,MSR_PR + beq 1f + BTB_FLUSH(r10) +1: +END_BTB_FLUSH_SECTION mfspr r10, SPRN_DEAR /* Get faulting address */ /* If we are faulting a kernel address, we have to use the @@ -545,6 +552,14 @@ END_FTR_SECTION_IFSET(CPU_FTR_EMB_HV) mfcr r13 stw r13, THREAD_NORMSAVE(3)(r10) DO_KVM BOOKE_INTERRUPT_ITLB_MISS SPRN_SRR1 +START_BTB_FLUSH_SECTION + mfspr r11, SPRN_SRR1 + andi. r10,r11,MSR_PR + beq 1f + BTB_FLUSH(r10) +1: +END_BTB_FLUSH_SECTION + mfspr r10, SPRN_SRR0 /* Get faulting address */ /* If we are faulting a kernel address, we have to use the diff --git a/arch/powerpc/kernel/module.c b/arch/powerpc/kernel/module.c index 9547381b631a..ff009be97a42 100644 --- a/arch/powerpc/kernel/module.c +++ b/arch/powerpc/kernel/module.c @@ -67,7 +67,15 @@ int module_finalize(const Elf_Ehdr *hdr, do_feature_fixups(powerpc_firmware_features, (void *)sect->sh_addr, (void *)sect->sh_addr + sect->sh_size); -#endif +#endif /* CONFIG_PPC64 */ + +#ifdef CONFIG_PPC_BARRIER_NOSPEC + sect = find_section(hdr, sechdrs, "__spec_barrier_fixup"); + if (sect != NULL) + do_barrier_nospec_fixups_range(barrier_nospec_enabled, + (void *)sect->sh_addr, + (void *)sect->sh_addr + sect->sh_size); +#endif /* CONFIG_PPC_BARRIER_NOSPEC */ sect = find_section(hdr, sechdrs, "__lwsync_fixup"); if (sect != NULL) diff --git a/arch/powerpc/kernel/security.c b/arch/powerpc/kernel/security.c new file mode 100644 index 000000000000..fe30ddfd51ee --- /dev/null +++ b/arch/powerpc/kernel/security.c @@ -0,0 +1,434 @@ +// SPDX-License-Identifier: GPL-2.0+ +// +// Security related flags and so on. +// +// Copyright 2018, Michael Ellerman, IBM Corporation. + +#include <linux/cpu.h> +#include <linux/kernel.h> +#include <linux/debugfs.h> +#include <linux/device.h> +#include <linux/seq_buf.h> + +#include <asm/debug.h> +#include <asm/asm-prototypes.h> +#include <asm/code-patching.h> +#include <asm/security_features.h> +#include <asm/setup.h> + + +unsigned long powerpc_security_features __read_mostly = SEC_FTR_DEFAULT; + +enum count_cache_flush_type { + COUNT_CACHE_FLUSH_NONE = 0x1, + COUNT_CACHE_FLUSH_SW = 0x2, + COUNT_CACHE_FLUSH_HW = 0x4, +}; +static enum count_cache_flush_type count_cache_flush_type = COUNT_CACHE_FLUSH_NONE; + +bool barrier_nospec_enabled; +static bool no_nospec; +static bool btb_flush_enabled; +#ifdef CONFIG_PPC_FSL_BOOK3E +static bool no_spectrev2; +#endif + +static void enable_barrier_nospec(bool enable) +{ + barrier_nospec_enabled = enable; + do_barrier_nospec_fixups(enable); +} + +void setup_barrier_nospec(void) +{ + bool enable; + + /* + * It would make sense to check SEC_FTR_SPEC_BAR_ORI31 below as well. + * But there's a good reason not to. The two flags we check below are + * both are enabled by default in the kernel, so if the hcall is not + * functional they will be enabled. + * On a system where the host firmware has been updated (so the ori + * functions as a barrier), but on which the hypervisor (KVM/Qemu) has + * not been updated, we would like to enable the barrier. Dropping the + * check for SEC_FTR_SPEC_BAR_ORI31 achieves that. The only downside is + * we potentially enable the barrier on systems where the host firmware + * is not updated, but that's harmless as it's a no-op. + */ + enable = security_ftr_enabled(SEC_FTR_FAVOUR_SECURITY) && + security_ftr_enabled(SEC_FTR_BNDS_CHK_SPEC_BAR); + + if (!no_nospec) + enable_barrier_nospec(enable); +} + +static int __init handle_nospectre_v1(char *p) +{ + no_nospec = true; + + return 0; +} +early_param("nospectre_v1", handle_nospectre_v1); + +#ifdef CONFIG_DEBUG_FS +static int barrier_nospec_set(void *data, u64 val) +{ + switch (val) { + case 0: + case 1: + break; + default: + return -EINVAL; + } + + if (!!val == !!barrier_nospec_enabled) + return 0; + + enable_barrier_nospec(!!val); + + return 0; +} + +static int barrier_nospec_get(void *data, u64 *val) +{ + *val = barrier_nospec_enabled ? 1 : 0; + return 0; +} + +DEFINE_SIMPLE_ATTRIBUTE(fops_barrier_nospec, + barrier_nospec_get, barrier_nospec_set, "%llu\n"); + +static __init int barrier_nospec_debugfs_init(void) +{ + debugfs_create_file("barrier_nospec", 0600, powerpc_debugfs_root, NULL, + &fops_barrier_nospec); + return 0; +} +device_initcall(barrier_nospec_debugfs_init); +#endif /* CONFIG_DEBUG_FS */ + +#ifdef CONFIG_PPC_FSL_BOOK3E +static int __init handle_nospectre_v2(char *p) +{ + no_spectrev2 = true; + + return 0; +} +early_param("nospectre_v2", handle_nospectre_v2); +void setup_spectre_v2(void) +{ + if (no_spectrev2) + do_btb_flush_fixups(); + else + btb_flush_enabled = true; +} +#endif /* CONFIG_PPC_FSL_BOOK3E */ + +#ifdef CONFIG_PPC_BOOK3S_64 +ssize_t cpu_show_meltdown(struct device *dev, struct device_attribute *attr, char *buf) +{ + bool thread_priv; + + thread_priv = security_ftr_enabled(SEC_FTR_L1D_THREAD_PRIV); + + if (rfi_flush || thread_priv) { + struct seq_buf s; + seq_buf_init(&s, buf, PAGE_SIZE - 1); + + seq_buf_printf(&s, "Mitigation: "); + + if (rfi_flush) + seq_buf_printf(&s, "RFI Flush"); + + if (rfi_flush && thread_priv) + seq_buf_printf(&s, ", "); + + if (thread_priv) + seq_buf_printf(&s, "L1D private per thread"); + + seq_buf_printf(&s, "\n"); + + return s.len; + } + + if (!security_ftr_enabled(SEC_FTR_L1D_FLUSH_HV) && + !security_ftr_enabled(SEC_FTR_L1D_FLUSH_PR)) + return sprintf(buf, "Not affected\n"); + + return sprintf(buf, "Vulnerable\n"); +} +#endif + +ssize_t cpu_show_spectre_v1(struct device *dev, struct device_attribute *attr, char *buf) +{ + struct seq_buf s; + + seq_buf_init(&s, buf, PAGE_SIZE - 1); + + if (security_ftr_enabled(SEC_FTR_BNDS_CHK_SPEC_BAR)) { + if (barrier_nospec_enabled) + seq_buf_printf(&s, "Mitigation: __user pointer sanitization"); + else + seq_buf_printf(&s, "Vulnerable"); + + if (security_ftr_enabled(SEC_FTR_SPEC_BAR_ORI31)) + seq_buf_printf(&s, ", ori31 speculation barrier enabled"); + + seq_buf_printf(&s, "\n"); + } else + seq_buf_printf(&s, "Not affected\n"); + + return s.len; +} + +ssize_t cpu_show_spectre_v2(struct device *dev, struct device_attribute *attr, char *buf) +{ + struct seq_buf s; + bool bcs, ccd; + + seq_buf_init(&s, buf, PAGE_SIZE - 1); + + bcs = security_ftr_enabled(SEC_FTR_BCCTRL_SERIALISED); + ccd = security_ftr_enabled(SEC_FTR_COUNT_CACHE_DISABLED); + + if (bcs || ccd) { + seq_buf_printf(&s, "Mitigation: "); + + if (bcs) + seq_buf_printf(&s, "Indirect branch serialisation (kernel only)"); + + if (bcs && ccd) + seq_buf_printf(&s, ", "); + + if (ccd) + seq_buf_printf(&s, "Indirect branch cache disabled"); + } else if (count_cache_flush_type != COUNT_CACHE_FLUSH_NONE) { + seq_buf_printf(&s, "Mitigation: Software count cache flush"); + + if (count_cache_flush_type == COUNT_CACHE_FLUSH_HW) + seq_buf_printf(&s, " (hardware accelerated)"); + } else if (btb_flush_enabled) { + seq_buf_printf(&s, "Mitigation: Branch predictor state flush"); + } else { + seq_buf_printf(&s, "Vulnerable"); + } + + seq_buf_printf(&s, "\n"); + + return s.len; +} + +#ifdef CONFIG_PPC_BOOK3S_64 +/* + * Store-forwarding barrier support. + */ + +static enum stf_barrier_type stf_enabled_flush_types; +static bool no_stf_barrier; +bool stf_barrier; + +static int __init handle_no_stf_barrier(char *p) +{ + pr_info("stf-barrier: disabled on command line."); + no_stf_barrier = true; + return 0; +} + +early_param("no_stf_barrier", handle_no_stf_barrier); + +/* This is the generic flag used by other architectures */ +static int __init handle_ssbd(char *p) +{ + if (!p || strncmp(p, "auto", 5) == 0 || strncmp(p, "on", 2) == 0 ) { + /* Until firmware tells us, we have the barrier with auto */ + return 0; + } else if (strncmp(p, "off", 3) == 0) { + handle_no_stf_barrier(NULL); + return 0; + } else + return 1; + + return 0; +} +early_param("spec_store_bypass_disable", handle_ssbd); + +/* This is the generic flag used by other architectures */ +static int __init handle_no_ssbd(char *p) +{ + handle_no_stf_barrier(NULL); + return 0; +} +early_param("nospec_store_bypass_disable", handle_no_ssbd); + +static void stf_barrier_enable(bool enable) +{ + if (enable) + do_stf_barrier_fixups(stf_enabled_flush_types); + else + do_stf_barrier_fixups(STF_BARRIER_NONE); + + stf_barrier = enable; +} + +void setup_stf_barrier(void) +{ + enum stf_barrier_type type; + bool enable, hv; + + hv = cpu_has_feature(CPU_FTR_HVMODE); + + /* Default to fallback in case fw-features are not available */ + if (cpu_has_feature(CPU_FTR_ARCH_207S)) + type = STF_BARRIER_SYNC_ORI; + else if (cpu_has_feature(CPU_FTR_ARCH_206)) + type = STF_BARRIER_FALLBACK; + else + type = STF_BARRIER_NONE; + + enable = security_ftr_enabled(SEC_FTR_FAVOUR_SECURITY) && + (security_ftr_enabled(SEC_FTR_L1D_FLUSH_PR) || + (security_ftr_enabled(SEC_FTR_L1D_FLUSH_HV) && hv)); + + if (type == STF_BARRIER_FALLBACK) { + pr_info("stf-barrier: fallback barrier available\n"); + } else if (type == STF_BARRIER_SYNC_ORI) { + pr_info("stf-barrier: hwsync barrier available\n"); + } else if (type == STF_BARRIER_EIEIO) { + pr_info("stf-barrier: eieio barrier available\n"); + } + + stf_enabled_flush_types = type; + + if (!no_stf_barrier) + stf_barrier_enable(enable); +} + +ssize_t cpu_show_spec_store_bypass(struct device *dev, struct device_attribute *attr, char *buf) +{ + if (stf_barrier && stf_enabled_flush_types != STF_BARRIER_NONE) { + const char *type; + switch (stf_enabled_flush_types) { + case STF_BARRIER_EIEIO: + type = "eieio"; + break; + case STF_BARRIER_SYNC_ORI: + type = "hwsync"; + break; + case STF_BARRIER_FALLBACK: + type = "fallback"; + break; + default: + type = "unknown"; + } + return sprintf(buf, "Mitigation: Kernel entry/exit barrier (%s)\n", type); + } + + if (!security_ftr_enabled(SEC_FTR_L1D_FLUSH_HV) && + !security_ftr_enabled(SEC_FTR_L1D_FLUSH_PR)) + return sprintf(buf, "Not affected\n"); + + return sprintf(buf, "Vulnerable\n"); +} + +#ifdef CONFIG_DEBUG_FS +static int stf_barrier_set(void *data, u64 val) +{ + bool enable; + + if (val == 1) + enable = true; + else if (val == 0) + enable = false; + else + return -EINVAL; + + /* Only do anything if we're changing state */ + if (enable != stf_barrier) + stf_barrier_enable(enable); + + return 0; +} + +static int stf_barrier_get(void *data, u64 *val) +{ + *val = stf_barrier ? 1 : 0; + return 0; +} + +DEFINE_SIMPLE_ATTRIBUTE(fops_stf_barrier, stf_barrier_get, stf_barrier_set, "%llu\n"); + +static __init int stf_barrier_debugfs_init(void) +{ + debugfs_create_file("stf_barrier", 0600, powerpc_debugfs_root, NULL, &fops_stf_barrier); + return 0; +} +device_initcall(stf_barrier_debugfs_init); +#endif /* CONFIG_DEBUG_FS */ + +static void toggle_count_cache_flush(bool enable) +{ + if (!enable || !security_ftr_enabled(SEC_FTR_FLUSH_COUNT_CACHE)) { + patch_instruction_site(&patch__call_flush_count_cache, PPC_INST_NOP); + count_cache_flush_type = COUNT_CACHE_FLUSH_NONE; + pr_info("count-cache-flush: software flush disabled.\n"); + return; + } + + patch_branch_site(&patch__call_flush_count_cache, + (u64)&flush_count_cache, BRANCH_SET_LINK); + + if (!security_ftr_enabled(SEC_FTR_BCCTR_FLUSH_ASSIST)) { + count_cache_flush_type = COUNT_CACHE_FLUSH_SW; + pr_info("count-cache-flush: full software flush sequence enabled.\n"); + return; + } + + patch_instruction_site(&patch__flush_count_cache_return, PPC_INST_BLR); + count_cache_flush_type = COUNT_CACHE_FLUSH_HW; + pr_info("count-cache-flush: hardware assisted flush sequence enabled\n"); +} + +void setup_count_cache_flush(void) +{ + toggle_count_cache_flush(true); +} + +#ifdef CONFIG_DEBUG_FS +static int count_cache_flush_set(void *data, u64 val) +{ + bool enable; + + if (val == 1) + enable = true; + else if (val == 0) + enable = false; + else + return -EINVAL; + + toggle_count_cache_flush(enable); + + return 0; +} + +static int count_cache_flush_get(void *data, u64 *val) +{ + if (count_cache_flush_type == COUNT_CACHE_FLUSH_NONE) + *val = 0; + else + *val = 1; + + return 0; +} + +DEFINE_SIMPLE_ATTRIBUTE(fops_count_cache_flush, count_cache_flush_get, + count_cache_flush_set, "%llu\n"); + +static __init int count_cache_flush_debugfs_init(void) +{ + debugfs_create_file("count_cache_flush", 0600, powerpc_debugfs_root, + NULL, &fops_count_cache_flush); + return 0; +} +device_initcall(count_cache_flush_debugfs_init); +#endif /* CONFIG_DEBUG_FS */ +#endif /* CONFIG_PPC_BOOK3S_64 */ diff --git a/arch/powerpc/kernel/setup_32.c b/arch/powerpc/kernel/setup_32.c index ad8c9db61237..cb37f27bb928 100644 --- a/arch/powerpc/kernel/setup_32.c +++ b/arch/powerpc/kernel/setup_32.c @@ -322,6 +322,9 @@ void __init setup_arch(char **cmdline_p) ppc_md.setup_arch(); if ( ppc_md.progress ) ppc_md.progress("arch: exit", 0x3eab); + setup_barrier_nospec(); + setup_spectre_v2(); + paging_init(); /* Initialize the MMU context management stuff */ diff --git a/arch/powerpc/kernel/setup_64.c b/arch/powerpc/kernel/setup_64.c index 9eb469bed22b..11590f6cb2f9 100644 --- a/arch/powerpc/kernel/setup_64.c +++ b/arch/powerpc/kernel/setup_64.c @@ -736,6 +736,9 @@ void __init setup_arch(char **cmdline_p) if (ppc_md.setup_arch) ppc_md.setup_arch(); + setup_barrier_nospec(); + setup_spectre_v2(); + paging_init(); /* Initialize the MMU context management stuff */ @@ -873,9 +876,6 @@ static void do_nothing(void *unused) void rfi_flush_enable(bool enable) { - if (rfi_flush == enable) - return; - if (enable) { do_rfi_flush_fixups(enabled_flush_types); on_each_cpu(do_nothing, NULL, 1); @@ -885,11 +885,15 @@ void rfi_flush_enable(bool enable) rfi_flush = enable; } -static void init_fallback_flush(void) +static void __ref init_fallback_flush(void) { u64 l1d_size, limit; int cpu; + /* Only allocate the fallback flush area once (at boot time). */ + if (l1d_flush_fallback_area) + return; + l1d_size = ppc64_caches.dsize; limit = min(safe_stack_limit(), ppc64_rma_size); @@ -902,34 +906,23 @@ static void init_fallback_flush(void) memset(l1d_flush_fallback_area, 0, l1d_size * 2); for_each_possible_cpu(cpu) { - /* - * The fallback flush is currently coded for 8-way - * associativity. Different associativity is possible, but it - * will be treated as 8-way and may not evict the lines as - * effectively. - * - * 128 byte lines are mandatory. - */ - u64 c = l1d_size / 8; - paca[cpu].rfi_flush_fallback_area = l1d_flush_fallback_area; - paca[cpu].l1d_flush_congruence = c; - paca[cpu].l1d_flush_sets = c / 128; + paca[cpu].l1d_flush_size = l1d_size; } } -void __init setup_rfi_flush(enum l1d_flush_type types, bool enable) +void setup_rfi_flush(enum l1d_flush_type types, bool enable) { if (types & L1D_FLUSH_FALLBACK) { - pr_info("rfi-flush: Using fallback displacement flush\n"); + pr_info("rfi-flush: fallback displacement flush available\n"); init_fallback_flush(); } if (types & L1D_FLUSH_ORI) - pr_info("rfi-flush: Using ori type flush\n"); + pr_info("rfi-flush: ori type flush available\n"); if (types & L1D_FLUSH_MTTRIG) - pr_info("rfi-flush: Using mttrig type flush\n"); + pr_info("rfi-flush: mttrig type flush available\n"); enabled_flush_types = types; @@ -940,13 +933,19 @@ void __init setup_rfi_flush(enum l1d_flush_type types, bool enable) #ifdef CONFIG_DEBUG_FS static int rfi_flush_set(void *data, u64 val) { + bool enable; + if (val == 1) - rfi_flush_enable(true); + enable = true; else if (val == 0) - rfi_flush_enable(false); + enable = false; else return -EINVAL; + /* Only do anything if we're changing state */ + if (enable != rfi_flush) + rfi_flush_enable(enable); + return 0; } @@ -965,12 +964,4 @@ static __init int rfi_flush_debugfs_init(void) } device_initcall(rfi_flush_debugfs_init); #endif - -ssize_t cpu_show_meltdown(struct device *dev, struct device_attribute *attr, char *buf) -{ - if (rfi_flush) - return sprintf(buf, "Mitigation: RFI Flush\n"); - - return sprintf(buf, "Vulnerable\n"); -} #endif /* CONFIG_PPC_BOOK3S_64 */ diff --git a/arch/powerpc/kernel/vmlinux.lds.S b/arch/powerpc/kernel/vmlinux.lds.S index 30f90e8f5dd6..9f6d79714373 100644 --- a/arch/powerpc/kernel/vmlinux.lds.S +++ b/arch/powerpc/kernel/vmlinux.lds.S @@ -75,13 +75,44 @@ SECTIONS #ifdef CONFIG_PPC64 . = ALIGN(8); + __stf_entry_barrier_fixup : AT(ADDR(__stf_entry_barrier_fixup) - LOAD_OFFSET) { + __start___stf_entry_barrier_fixup = .; + *(__stf_entry_barrier_fixup) + __stop___stf_entry_barrier_fixup = .; + } + + . = ALIGN(8); + __stf_exit_barrier_fixup : AT(ADDR(__stf_exit_barrier_fixup) - LOAD_OFFSET) { + __start___stf_exit_barrier_fixup = .; + *(__stf_exit_barrier_fixup) + __stop___stf_exit_barrier_fixup = .; + } + + . = ALIGN(8); __rfi_flush_fixup : AT(ADDR(__rfi_flush_fixup) - LOAD_OFFSET) { __start___rfi_flush_fixup = .; *(__rfi_flush_fixup) __stop___rfi_flush_fixup = .; } -#endif +#endif /* CONFIG_PPC64 */ +#ifdef CONFIG_PPC_BARRIER_NOSPEC + . = ALIGN(8); + __spec_barrier_fixup : AT(ADDR(__spec_barrier_fixup) - LOAD_OFFSET) { + __start___barrier_nospec_fixup = .; + *(__barrier_nospec_fixup) + __stop___barrier_nospec_fixup = .; + } +#endif /* CONFIG_PPC_BARRIER_NOSPEC */ + +#ifdef CONFIG_PPC_FSL_BOOK3E + . = ALIGN(8); + __spec_btb_flush_fixup : AT(ADDR(__spec_btb_flush_fixup) - LOAD_OFFSET) { + __start__btb_flush_fixup = .; + *(__btb_flush_fixup) + __stop__btb_flush_fixup = .; + } +#endif EXCEPTION_TABLE(0) NOTES :kernel :notes |