diff options
| -rw-r--r-- | arch/x86/include/asm/alternative.h | 8 | ||||
| -rw-r--r-- | arch/x86/kernel/alternative.c | 8 | ||||
| -rw-r--r-- | arch/x86/net/bpf_jit_comp.c | 2 |
3 files changed, 17 insertions, 1 deletions
diff --git a/arch/x86/include/asm/alternative.h b/arch/x86/include/asm/alternative.h index 4463cf38c169..fd3b73017738 100644 --- a/arch/x86/include/asm/alternative.h +++ b/arch/x86/include/asm/alternative.h @@ -5,6 +5,7 @@ #include <linux/types.h> #include <linux/stringify.h> #include <asm/asm.h> +#include <asm/bug.h> #define ALTINSTR_FLAG_INV (1 << 15) #define ALT_NOT(feat) ((feat) | ALTINSTR_FLAG_INV) @@ -85,10 +86,17 @@ struct module; extern void its_init_mod(struct module *mod); extern void its_fini_mod(struct module *mod); extern void its_free_mod(struct module *mod); +extern u8 *its_static_thunk(int reg); #else /* CONFIG_MITIGATION_ITS */ static inline void its_init_mod(struct module *mod) { } static inline void its_fini_mod(struct module *mod) { } static inline void its_free_mod(struct module *mod) { } +static inline u8 *its_static_thunk(int reg) +{ + WARN_ONCE(1, "ITS not compiled in"); + + return NULL; +} #endif #if defined(CONFIG_RETHUNK) && defined(CONFIG_OBJTOOL) diff --git a/arch/x86/kernel/alternative.c b/arch/x86/kernel/alternative.c index 7d61f8c7ec38..3bc6be6404d2 100644 --- a/arch/x86/kernel/alternative.c +++ b/arch/x86/kernel/alternative.c @@ -596,6 +596,14 @@ static bool cpu_wants_indirect_its_thunk_at(unsigned long addr, int reg) /* Lower-half of the cacheline? */ return !(addr & 0x20); } + +u8 *its_static_thunk(int reg) +{ + u8 *thunk = __x86_indirect_its_thunk_array[reg]; + + return thunk; +} + #endif /* diff --git a/arch/x86/net/bpf_jit_comp.c b/arch/x86/net/bpf_jit_comp.c index b5fd521a7fa0..f3068bb53c4d 100644 --- a/arch/x86/net/bpf_jit_comp.c +++ b/arch/x86/net/bpf_jit_comp.c @@ -467,7 +467,7 @@ static void emit_indirect_jump(u8 **pprog, int reg, u8 *ip) if (IS_ENABLED(CONFIG_MITIGATION_ITS) && cpu_feature_enabled(X86_FEATURE_INDIRECT_THUNK_ITS)) { OPTIMIZER_HIDE_VAR(reg); - emit_jump(&prog, &__x86_indirect_its_thunk_array[reg], ip); + emit_jump(&prog, its_static_thunk(reg), ip); } else if (cpu_feature_enabled(X86_FEATURE_RETPOLINE_LFENCE)) { EMIT_LFENCE(); EMIT2(0xFF, 0xE0 + reg); |