diff --git a/arch/arm64/include/asm/cputype.h b/arch/arm64/include/asm/cputype.h index ae983d3354568307e4bf26eb3f2a8515f07d40c3..6db79b5ad463d1f1d8a93980dbb830e1f6ade1b2 100644 --- a/arch/arm64/include/asm/cputype.h +++ b/arch/arm64/include/asm/cputype.h @@ -77,11 +77,13 @@ #define ARM_CPU_PART_CORTEX_A76 0xD0B #define ARM_CPU_PART_NEOVERSE_N1 0xD0C #define ARM_CPU_PART_CORTEX_A77 0xD0D +#define ARM_CPU_PART_CORTEX_A76AE 0xD0E #define ARM_CPU_PART_NEOVERSE_V1 0xD40 #define ARM_CPU_PART_CORTEX_A78 0xD41 #define ARM_CPU_PART_CORTEX_A78AE 0xD42 #define ARM_CPU_PART_CORTEX_X1 0xD44 #define ARM_CPU_PART_CORTEX_A510 0xD46 +#define ARM_CPU_PART_CORTEX_X1C 0xD4C #define ARM_CPU_PART_CORTEX_A520 0xD80 #define ARM_CPU_PART_CORTEX_A710 0xD47 #define ARM_CPU_PART_CORTEX_A715 0xD4D @@ -173,11 +175,13 @@ #define MIDR_CORTEX_A76 MIDR_CPU_MODEL(ARM_CPU_IMP_ARM, ARM_CPU_PART_CORTEX_A76) #define MIDR_NEOVERSE_N1 MIDR_CPU_MODEL(ARM_CPU_IMP_ARM, ARM_CPU_PART_NEOVERSE_N1) #define MIDR_CORTEX_A77 MIDR_CPU_MODEL(ARM_CPU_IMP_ARM, ARM_CPU_PART_CORTEX_A77) +#define MIDR_CORTEX_A76AE MIDR_CPU_MODEL(ARM_CPU_IMP_ARM, ARM_CPU_PART_CORTEX_A76AE) #define MIDR_NEOVERSE_V1 MIDR_CPU_MODEL(ARM_CPU_IMP_ARM, ARM_CPU_PART_NEOVERSE_V1) #define MIDR_CORTEX_A78 MIDR_CPU_MODEL(ARM_CPU_IMP_ARM, ARM_CPU_PART_CORTEX_A78) #define MIDR_CORTEX_A78AE MIDR_CPU_MODEL(ARM_CPU_IMP_ARM, ARM_CPU_PART_CORTEX_A78AE) #define MIDR_CORTEX_X1 MIDR_CPU_MODEL(ARM_CPU_IMP_ARM, ARM_CPU_PART_CORTEX_X1) #define MIDR_CORTEX_A510 MIDR_CPU_MODEL(ARM_CPU_IMP_ARM, ARM_CPU_PART_CORTEX_A510) +#define MIDR_CORTEX_X1C MIDR_CPU_MODEL(ARM_CPU_IMP_ARM, ARM_CPU_PART_CORTEX_X1C) #define MIDR_CORTEX_A520 MIDR_CPU_MODEL(ARM_CPU_IMP_ARM, ARM_CPU_PART_CORTEX_A520) #define MIDR_CORTEX_A710 MIDR_CPU_MODEL(ARM_CPU_IMP_ARM, ARM_CPU_PART_CORTEX_A710) #define MIDR_CORTEX_A715 MIDR_CPU_MODEL(ARM_CPU_IMP_ARM, ARM_CPU_PART_CORTEX_A715) diff --git a/arch/arm64/include/asm/insn.h b/arch/arm64/include/asm/insn.h index 0ccf51afde31a600cb7efbb3008f8ec17f4ed7dd..12c0278294e3f6856810c630b4f54b7478e14b04 100644 --- a/arch/arm64/include/asm/insn.h +++ b/arch/arm64/include/asm/insn.h @@ -687,6 +687,7 @@ u32 aarch64_insn_gen_cas(enum aarch64_insn_register result, } #endif u32 aarch64_insn_gen_dmb(enum aarch64_insn_mb_type type); +u32 aarch64_insn_gen_dsb(enum aarch64_insn_mb_type type); s32 aarch64_get_branch_offset(u32 insn); u32 aarch64_set_branch_offset(u32 insn, s32 offset); diff --git a/arch/arm64/include/asm/spectre.h b/arch/arm64/include/asm/spectre.h index 9cc501450486d83ac9b3bd1bf6fa3375d0bba6f3..32475d19c15f445fcbdd735fe6484c6d684976b9 100644 --- a/arch/arm64/include/asm/spectre.h +++ b/arch/arm64/include/asm/spectre.h @@ -97,7 +97,9 @@ enum mitigation_state arm64_get_meltdown_state(void); enum mitigation_state arm64_get_spectre_bhb_state(void); bool is_spectre_bhb_affected(const struct arm64_cpu_capabilities *entry, int scope); -u8 spectre_bhb_loop_affected(int scope); +extern bool __nospectre_bhb; +u8 get_spectre_bhb_loop_value(void); +bool is_spectre_bhb_fw_mitigated(void); void spectre_bhb_enable_mitigation(const struct arm64_cpu_capabilities *__unused); bool try_emulate_el1_ssbs(struct pt_regs *regs, u32 instr); diff --git a/arch/arm64/kernel/proton-pack.c b/arch/arm64/kernel/proton-pack.c index 4bca7ad7b5e336e5ea3d25411629e509a5d5be29..7153079af2c591e3d6ae936e12f4f91ecbaea79a 100644 --- a/arch/arm64/kernel/proton-pack.c +++ b/arch/arm64/kernel/proton-pack.c @@ -845,52 +845,87 @@ static unsigned long system_bhb_mitigations; * This must be called with SCOPE_LOCAL_CPU for each type of CPU, before any * SCOPE_SYSTEM call will give the right answer. */ -u8 spectre_bhb_loop_affected(int scope) +static bool is_spectre_bhb_safe(int scope) +{ + static const struct midr_range spectre_bhb_safe_list[] = { + MIDR_ALL_VERSIONS(MIDR_CORTEX_A35), + MIDR_ALL_VERSIONS(MIDR_CORTEX_A53), + MIDR_ALL_VERSIONS(MIDR_CORTEX_A55), + MIDR_ALL_VERSIONS(MIDR_CORTEX_A510), + MIDR_ALL_VERSIONS(MIDR_CORTEX_A520), + MIDR_ALL_VERSIONS(MIDR_BRAHMA_B53), + MIDR_ALL_VERSIONS(MIDR_QCOM_KRYO_2XX_SILVER), + MIDR_ALL_VERSIONS(MIDR_QCOM_KRYO_3XX_SILVER), + MIDR_ALL_VERSIONS(MIDR_QCOM_KRYO_4XX_SILVER), + {}, + }; + static bool all_safe = true; + + if (scope != SCOPE_LOCAL_CPU) + return all_safe; + + if (is_midr_in_range_list(read_cpuid_id(), spectre_bhb_safe_list)) + return true; + + all_safe = false; + + return false; +} + +static u8 spectre_bhb_loop_affected(void) { u8 k = 0; - static u8 max_bhb_k; - - if (scope == SCOPE_LOCAL_CPU) { - static const struct midr_range spectre_bhb_k32_list[] = { - MIDR_ALL_VERSIONS(MIDR_CORTEX_A78), - MIDR_ALL_VERSIONS(MIDR_CORTEX_A78AE), - MIDR_ALL_VERSIONS(MIDR_CORTEX_A78C), - MIDR_ALL_VERSIONS(MIDR_CORTEX_X1), - MIDR_ALL_VERSIONS(MIDR_CORTEX_A710), - MIDR_ALL_VERSIONS(MIDR_CORTEX_X2), - MIDR_ALL_VERSIONS(MIDR_NEOVERSE_N2), - MIDR_ALL_VERSIONS(MIDR_NEOVERSE_V1), - {}, - }; - static const struct midr_range spectre_bhb_k24_list[] = { - MIDR_ALL_VERSIONS(MIDR_CORTEX_A76), - MIDR_ALL_VERSIONS(MIDR_CORTEX_A77), - MIDR_ALL_VERSIONS(MIDR_NEOVERSE_N1), - {}, - }; - static const struct midr_range spectre_bhb_k11_list[] = { - MIDR_ALL_VERSIONS(MIDR_AMPERE1), - {}, - }; - static const struct midr_range spectre_bhb_k8_list[] = { - MIDR_ALL_VERSIONS(MIDR_CORTEX_A72), - MIDR_ALL_VERSIONS(MIDR_CORTEX_A57), - {}, - }; - - if (is_midr_in_range_list(read_cpuid_id(), spectre_bhb_k32_list)) - k = 32; - else if (is_midr_in_range_list(read_cpuid_id(), spectre_bhb_k24_list)) - k = 24; - else if (is_midr_in_range_list(read_cpuid_id(), spectre_bhb_k11_list)) - k = 11; - else if (is_midr_in_range_list(read_cpuid_id(), spectre_bhb_k8_list)) - k = 8; - - max_bhb_k = max(max_bhb_k, k); - } else { - k = max_bhb_k; - } + + static const struct midr_range spectre_bhb_k132_list[] = { + MIDR_ALL_VERSIONS(MIDR_CORTEX_X3), + MIDR_ALL_VERSIONS(MIDR_NEOVERSE_V2), + }; + static const struct midr_range spectre_bhb_k38_list[] = { + MIDR_ALL_VERSIONS(MIDR_CORTEX_A715), + MIDR_ALL_VERSIONS(MIDR_CORTEX_A720), + }; + static const struct midr_range spectre_bhb_k32_list[] = { + MIDR_ALL_VERSIONS(MIDR_CORTEX_A78), + MIDR_ALL_VERSIONS(MIDR_CORTEX_A78AE), + MIDR_ALL_VERSIONS(MIDR_CORTEX_A78C), + MIDR_ALL_VERSIONS(MIDR_CORTEX_X1), + MIDR_ALL_VERSIONS(MIDR_CORTEX_X1C), + MIDR_ALL_VERSIONS(MIDR_CORTEX_A710), + MIDR_ALL_VERSIONS(MIDR_CORTEX_X2), + MIDR_ALL_VERSIONS(MIDR_NEOVERSE_N2), + MIDR_ALL_VERSIONS(MIDR_NEOVERSE_V1), + {}, + }; + static const struct midr_range spectre_bhb_k24_list[] = { + MIDR_ALL_VERSIONS(MIDR_CORTEX_A76), + MIDR_ALL_VERSIONS(MIDR_CORTEX_A76AE), + MIDR_ALL_VERSIONS(MIDR_CORTEX_A77), + MIDR_ALL_VERSIONS(MIDR_NEOVERSE_N1), + MIDR_ALL_VERSIONS(MIDR_QCOM_KRYO_4XX_GOLD), + {}, + }; + static const struct midr_range spectre_bhb_k11_list[] = { + MIDR_ALL_VERSIONS(MIDR_AMPERE1), + {}, + }; + static const struct midr_range spectre_bhb_k8_list[] = { + MIDR_ALL_VERSIONS(MIDR_CORTEX_A72), + MIDR_ALL_VERSIONS(MIDR_CORTEX_A57), + {}, + }; + + if (is_midr_in_range_list(read_cpuid_id(), spectre_bhb_k132_list)) + k = 132; + else if (is_midr_in_range_list(read_cpuid_id(), spectre_bhb_k38_list)) + k = 38; + else if (is_midr_in_range_list(read_cpuid_id(), spectre_bhb_k32_list)) + k = 32; + else if (is_midr_in_range_list(read_cpuid_id(), spectre_bhb_k24_list)) + k = 24; + else if (is_midr_in_range_list(read_cpuid_id(), spectre_bhb_k11_list)) + k = 11; + else if (is_midr_in_range_list(read_cpuid_id(), spectre_bhb_k8_list)) + k = 8; return k; } @@ -916,29 +951,13 @@ static enum mitigation_state spectre_bhb_get_cpu_fw_mitigation_state(void) } } -static bool is_spectre_bhb_fw_affected(int scope) +static bool has_spectre_bhb_fw_mitigation(void) { - static bool system_affected; enum mitigation_state fw_state; bool has_smccc = arm_smccc_1_1_get_conduit() != SMCCC_CONDUIT_NONE; - static const struct midr_range spectre_bhb_firmware_mitigated_list[] = { - MIDR_ALL_VERSIONS(MIDR_CORTEX_A73), - MIDR_ALL_VERSIONS(MIDR_CORTEX_A75), - {}, - }; - bool cpu_in_list = is_midr_in_range_list(read_cpuid_id(), - spectre_bhb_firmware_mitigated_list); - - if (scope != SCOPE_LOCAL_CPU) - return system_affected; fw_state = spectre_bhb_get_cpu_fw_mitigation_state(); - if (cpu_in_list || (has_smccc && fw_state == SPECTRE_MITIGATED)) { - system_affected = true; - return true; - } - - return false; + return has_smccc && fw_state == SPECTRE_MITIGATED; } static bool supports_ecbhb(int scope) @@ -954,6 +973,8 @@ static bool supports_ecbhb(int scope) ID_AA64MMFR1_EL1_ECBHB_SHIFT); } +static u8 max_bhb_k; + bool is_spectre_bhb_affected(const struct arm64_cpu_capabilities *entry, int scope) { @@ -962,16 +983,23 @@ bool is_spectre_bhb_affected(const struct arm64_cpu_capabilities *entry, if (supports_csv2p3(scope)) return false; - if (supports_clearbhb(scope)) - return true; + if (is_spectre_bhb_safe(scope)) + return false; - if (spectre_bhb_loop_affected(scope)) - return true; + /* + * At this point the core isn't known to be "safe" so we're going to + * assume it's vulnerable. We still need to update `max_bhb_k` though, + * but only if we aren't mitigating with clearbhb though. + */ + if (scope == SCOPE_LOCAL_CPU && !supports_clearbhb(SCOPE_LOCAL_CPU)) + max_bhb_k = max(max_bhb_k, spectre_bhb_loop_affected()); - if (is_spectre_bhb_fw_affected(scope)) - return true; + return true; +} - return false; +u8 get_spectre_bhb_loop_value(void) +{ + return max_bhb_k; } static void this_cpu_set_vectors(enum arm64_bp_harden_el1_vectors slot) @@ -991,7 +1019,7 @@ static void this_cpu_set_vectors(enum arm64_bp_harden_el1_vectors slot) isb(); } -static bool __read_mostly __nospectre_bhb; +bool __read_mostly __nospectre_bhb; static int __init parse_spectre_bhb_param(char *str) { __nospectre_bhb = true; @@ -1002,7 +1030,7 @@ early_param("nospectre_bhb", parse_spectre_bhb_param); void spectre_bhb_enable_mitigation(const struct arm64_cpu_capabilities *entry) { bp_hardening_cb_t cpu_cb; - enum mitigation_state fw_state, state = SPECTRE_VULNERABLE; + enum mitigation_state state = SPECTRE_VULNERABLE; struct bp_hardening_data *data = this_cpu_ptr(&bp_hardening_data); if (!is_spectre_bhb_affected(entry, SCOPE_LOCAL_CPU)) @@ -1028,7 +1056,7 @@ void spectre_bhb_enable_mitigation(const struct arm64_cpu_capabilities *entry) this_cpu_set_vectors(EL1_VECTOR_BHB_CLEAR_INSN); state = SPECTRE_MITIGATED; set_bit(BHB_INSN, &system_bhb_mitigations); - } else if (spectre_bhb_loop_affected(SCOPE_LOCAL_CPU)) { + } else if (spectre_bhb_loop_affected()) { /* * Ensure KVM uses the indirect vector which will have the * branchy-loop added. A57/A72-r0 will already have selected @@ -1041,37 +1069,39 @@ void spectre_bhb_enable_mitigation(const struct arm64_cpu_capabilities *entry) this_cpu_set_vectors(EL1_VECTOR_BHB_LOOP); state = SPECTRE_MITIGATED; set_bit(BHB_LOOP, &system_bhb_mitigations); - } else if (is_spectre_bhb_fw_affected(SCOPE_LOCAL_CPU)) { - fw_state = spectre_bhb_get_cpu_fw_mitigation_state(); - if (fw_state == SPECTRE_MITIGATED) { - /* - * Ensure KVM uses one of the spectre bp_hardening - * vectors. The indirect vector doesn't include the EL3 - * call, so needs upgrading to - * HYP_VECTOR_SPECTRE_INDIRECT. - */ - if (!data->slot || data->slot == HYP_VECTOR_INDIRECT) - data->slot += 1; - - this_cpu_set_vectors(EL1_VECTOR_BHB_FW); - - /* - * The WA3 call in the vectors supersedes the WA1 call - * made during context-switch. Uninstall any firmware - * bp_hardening callback. - */ - cpu_cb = spectre_v2_get_sw_mitigation_cb(); - if (__this_cpu_read(bp_hardening_data.fn) != cpu_cb) - __this_cpu_write(bp_hardening_data.fn, NULL); - - state = SPECTRE_MITIGATED; - set_bit(BHB_FW, &system_bhb_mitigations); - } + } else if (has_spectre_bhb_fw_mitigation()) { + /* + * Ensure KVM uses one of the spectre bp_hardening + * vectors. The indirect vector doesn't include the EL3 + * call, so needs upgrading to + * HYP_VECTOR_SPECTRE_INDIRECT. + */ + if (!data->slot || data->slot == HYP_VECTOR_INDIRECT) + data->slot += 1; + + this_cpu_set_vectors(EL1_VECTOR_BHB_FW); + + /* + * The WA3 call in the vectors supersedes the WA1 call + * made during context-switch. Uninstall any firmware + * bp_hardening callback. + */ + cpu_cb = spectre_v2_get_sw_mitigation_cb(); + if (__this_cpu_read(bp_hardening_data.fn) != cpu_cb) + __this_cpu_write(bp_hardening_data.fn, NULL); + + state = SPECTRE_MITIGATED; + set_bit(BHB_FW, &system_bhb_mitigations); } update_mitigation_state(&spectre_bhb_state, state); } +bool is_spectre_bhb_fw_mitigated(void) +{ + return test_bit(BHB_FW, &system_bhb_mitigations); +} + /* Patched to NOP when enabled */ void noinstr spectre_bhb_patch_loop_mitigation_enable(struct alt_instr *alt, __le32 *origptr, @@ -1100,7 +1130,6 @@ void noinstr spectre_bhb_patch_loop_iter(struct alt_instr *alt, { u8 rd; u32 insn; - u16 loop_count = spectre_bhb_loop_affected(SCOPE_SYSTEM); BUG_ON(nr_inst != 1); /* MOV -> MOV */ @@ -1109,7 +1138,7 @@ void noinstr spectre_bhb_patch_loop_iter(struct alt_instr *alt, insn = le32_to_cpu(*origptr); rd = aarch64_insn_decode_register(AARCH64_INSN_REGTYPE_RD, insn); - insn = aarch64_insn_gen_movewide(rd, loop_count, 0, + insn = aarch64_insn_gen_movewide(rd, max_bhb_k, 0, AARCH64_INSN_VARIANT_64BIT, AARCH64_INSN_MOVEWIDE_ZERO); *updptr++ = cpu_to_le32(insn); diff --git a/arch/arm64/lib/insn.c b/arch/arm64/lib/insn.c index a635ab83fee359421cd7c26bf6b59324feb21522..7232b1e70a125f34f9f7d0cc05d51d89b8d40d1a 100644 --- a/arch/arm64/lib/insn.c +++ b/arch/arm64/lib/insn.c @@ -5,6 +5,7 @@ * * Copyright (C) 2014-2016 Zi Shen Lim */ +#include #include #include #include @@ -1471,43 +1472,41 @@ u32 aarch64_insn_gen_extr(enum aarch64_insn_variant variant, return aarch64_insn_encode_register(AARCH64_INSN_REGTYPE_RM, insn, Rm); } -u32 aarch64_insn_gen_dmb(enum aarch64_insn_mb_type type) +static u32 __get_barrier_crm_val(enum aarch64_insn_mb_type type) { - u32 opt; - u32 insn; - switch (type) { case AARCH64_INSN_MB_SY: - opt = 0xf; - break; + return 0xf; case AARCH64_INSN_MB_ST: - opt = 0xe; - break; + return 0xe; case AARCH64_INSN_MB_LD: - opt = 0xd; - break; + return 0xd; case AARCH64_INSN_MB_ISH: - opt = 0xb; - break; + return 0xb; case AARCH64_INSN_MB_ISHST: - opt = 0xa; - break; + return 0xa; case AARCH64_INSN_MB_ISHLD: - opt = 0x9; - break; + return 0x9; case AARCH64_INSN_MB_NSH: - opt = 0x7; - break; + return 0x7; case AARCH64_INSN_MB_NSHST: - opt = 0x6; - break; + return 0x6; case AARCH64_INSN_MB_NSHLD: - opt = 0x5; - break; + return 0x5; default: - pr_err("%s: unknown dmb type %d\n", __func__, type); + pr_err("%s: unknown barrier type %d\n", __func__, type); return AARCH64_BREAK_FAULT; } +} + +u32 aarch64_insn_gen_dmb(enum aarch64_insn_mb_type type) +{ + u32 opt; + u32 insn; + + opt = __get_barrier_crm_val(type); + if (opt == AARCH64_BREAK_FAULT) + return AARCH64_BREAK_FAULT; insn = aarch64_insn_get_dmb_value(); insn &= ~GENMASK(11, 8); @@ -1515,3 +1514,18 @@ u32 aarch64_insn_gen_dmb(enum aarch64_insn_mb_type type) return insn; } + +u32 aarch64_insn_gen_dsb(enum aarch64_insn_mb_type type) +{ + u32 opt, insn; + + opt = __get_barrier_crm_val(type); + if (opt == AARCH64_BREAK_FAULT) + return AARCH64_BREAK_FAULT; + + insn = aarch64_insn_get_dsb_base_value(); + insn &= ~GENMASK(11, 8); + insn |= (opt << 8); + + return insn; +} diff --git a/arch/arm64/net/bpf_jit_comp.c b/arch/arm64/net/bpf_jit_comp.c index 7cd20450bd5d96d223ca8d8c6131c5db872f1b77..8b957d2f60ebe2ad04b86359d03cc82c4ba0837f 100644 --- a/arch/arm64/net/bpf_jit_comp.c +++ b/arch/arm64/net/bpf_jit_comp.c @@ -7,6 +7,7 @@ #define pr_fmt(fmt) "bpf_jit: " fmt +#include #include #include #include @@ -17,6 +18,7 @@ #include #include #include +#include #include #include #include @@ -653,7 +655,51 @@ static void build_plt(struct jit_ctx *ctx) plt->target = (u64)&dummy_tramp; } -static void build_epilogue(struct jit_ctx *ctx) +/* Clobbers BPF registers 1-4, aka x0-x3 */ +static void __maybe_unused build_bhb_mitigation(struct jit_ctx *ctx) +{ + const u8 r1 = bpf2a64[BPF_REG_1]; /* aka x0 */ + u8 k = get_spectre_bhb_loop_value(); + + if (!IS_ENABLED(CONFIG_MITIGATE_SPECTRE_BRANCH_HISTORY) || + cpu_mitigations_off() || __nospectre_bhb || + arm64_get_spectre_v2_state() == SPECTRE_VULNERABLE) + return; + + if (capable(CAP_SYS_ADMIN)) + return; + + if (supports_clearbhb(SCOPE_SYSTEM)) { + emit(aarch64_insn_gen_hint(AARCH64_INSN_HINT_CLEARBHB), ctx); + return; + } + + if (k) { + emit_a64_mov_i64(r1, k, ctx); + emit(A64_B(1), ctx); + emit(A64_SUBS_I(true, r1, r1, 1), ctx); + emit(A64_B_(A64_COND_NE, -2), ctx); + emit(aarch64_insn_gen_dsb(AARCH64_INSN_MB_ISH), ctx); + emit(aarch64_insn_get_isb_value(), ctx); + } + + if (is_spectre_bhb_fw_mitigated()) { + emit(A64_ORR_I(false, r1, AARCH64_INSN_REG_ZR, + ARM_SMCCC_ARCH_WORKAROUND_3), ctx); + switch (arm_smccc_1_1_get_conduit()) { + case SMCCC_CONDUIT_HVC: + emit(aarch64_insn_get_hvc_value(), ctx); + break; + case SMCCC_CONDUIT_SMC: + emit(aarch64_insn_get_smc_value(), ctx); + break; + default: + pr_err_once("Firmware mitigation enabled with unknown conduit\n"); + } + } +} + +static void build_epilogue(struct jit_ctx *ctx, bool was_classic) { const u8 r0 = bpf2a64[BPF_REG_0]; const u8 r6 = bpf2a64[BPF_REG_6]; @@ -675,10 +721,13 @@ static void build_epilogue(struct jit_ctx *ctx) emit(A64_POP(r8, r9, A64_SP), ctx); emit(A64_POP(r6, r7, A64_SP), ctx); + if (was_classic) + build_bhb_mitigation(ctx); + /* Restore FP/LR registers */ emit(A64_POP(A64_FP, A64_LR, A64_SP), ctx); - /* Set return value */ + /* Move the return value from bpf:r0 (aka x7) to x0 */ emit(A64_MOV(1, A64_R(0), r0), ctx); /* Authenticate lr */ @@ -1586,7 +1635,7 @@ struct bpf_prog *bpf_int_jit_compile(struct bpf_prog *prog) } ctx.epilogue_offset = ctx.idx; - build_epilogue(&ctx); + build_epilogue(&ctx, was_classic); build_plt(&ctx); extable_align = __alignof__(struct exception_table_entry); @@ -1622,7 +1671,7 @@ struct bpf_prog *bpf_int_jit_compile(struct bpf_prog *prog) goto out_off; } - build_epilogue(&ctx); + build_epilogue(&ctx, was_classic); build_plt(&ctx); /* 3. Extra pass to validate JITed code. */