diff options
Diffstat (limited to 'arch/x86')
| -rw-r--r-- | arch/x86/Kconfig | 1 | ||||
| -rw-r--r-- | arch/x86/include/asm/kprobes.h | 4 | ||||
| -rw-r--r-- | arch/x86/include/asm/ptrace.h | 5 | ||||
| -rw-r--r-- | arch/x86/kernel/kprobes/ftrace.c | 14 | ||||
| -rw-r--r-- | arch/x86/net/bpf_jit_comp.c | 49 |
5 files changed, 69 insertions, 4 deletions
diff --git a/arch/x86/Kconfig b/arch/x86/Kconfig index d4fc98c50378..45dc6233f2b9 100644 --- a/arch/x86/Kconfig +++ b/arch/x86/Kconfig @@ -154,6 +154,7 @@ config X86 select HAVE_KERNEL_XZ select HAVE_KPROBES select HAVE_KPROBES_ON_FTRACE + select HAVE_KPROBE_OVERRIDE select HAVE_KRETPROBES select HAVE_KVM select HAVE_LIVEPATCH if X86_64 diff --git a/arch/x86/include/asm/kprobes.h b/arch/x86/include/asm/kprobes.h index 9f2e3102e0bb..36abb23a7a35 100644 --- a/arch/x86/include/asm/kprobes.h +++ b/arch/x86/include/asm/kprobes.h @@ -67,6 +67,10 @@ extern const int kretprobe_blacklist_size; void arch_remove_kprobe(struct kprobe *p); asmlinkage void kretprobe_trampoline(void); +#ifdef CONFIG_KPROBES_ON_FTRACE +extern void arch_ftrace_kprobe_override_function(struct pt_regs *regs); +#endif + /* Architecture specific copy of original instruction*/ struct arch_specific_insn { /* copy of the original instruction */ diff --git a/arch/x86/include/asm/ptrace.h b/arch/x86/include/asm/ptrace.h index 14131dd06b29..6de1fd3d0097 100644 --- a/arch/x86/include/asm/ptrace.h +++ b/arch/x86/include/asm/ptrace.h @@ -109,6 +109,11 @@ static inline unsigned long regs_return_value(struct pt_regs *regs) return regs->ax; } +static inline void regs_set_return_value(struct pt_regs *regs, unsigned long rc) +{ + regs->ax = rc; +} + /* * user_mode(regs) determines whether a register set came from user * mode. On x86_32, this is true if V8086 mode was enabled OR if the diff --git a/arch/x86/kernel/kprobes/ftrace.c b/arch/x86/kernel/kprobes/ftrace.c index 8dc0161cec8f..1ea748d682fd 100644 --- a/arch/x86/kernel/kprobes/ftrace.c +++ b/arch/x86/kernel/kprobes/ftrace.c @@ -97,3 +97,17 @@ int arch_prepare_kprobe_ftrace(struct kprobe *p) p->ainsn.boostable = false; return 0; } + +asmlinkage void override_func(void); +asm( + ".type override_func, @function\n" + "override_func:\n" + " ret\n" + ".size override_func, .-override_func\n" +); + +void arch_ftrace_kprobe_override_function(struct pt_regs *regs) +{ + regs->ip = (unsigned long)&override_func; +} +NOKPROBE_SYMBOL(arch_ftrace_kprobe_override_function); diff --git a/arch/x86/net/bpf_jit_comp.c b/arch/x86/net/bpf_jit_comp.c index 0554e8aef4d5..87f214fbe66e 100644 --- a/arch/x86/net/bpf_jit_comp.c +++ b/arch/x86/net/bpf_jit_comp.c @@ -1109,19 +1109,29 @@ common_load: return proglen; } +struct x64_jit_data { + struct bpf_binary_header *header; + int *addrs; + u8 *image; + int proglen; + struct jit_context ctx; +}; + struct bpf_prog *bpf_int_jit_compile(struct bpf_prog *prog) { struct bpf_binary_header *header = NULL; struct bpf_prog *tmp, *orig_prog = prog; + struct x64_jit_data *jit_data; int proglen, oldproglen = 0; struct jit_context ctx = {}; bool tmp_blinded = false; + bool extra_pass = false; u8 *image = NULL; int *addrs; int pass; int i; - if (!bpf_jit_enable) + if (!prog->jit_requested) return orig_prog; tmp = bpf_jit_blind_constants(prog); @@ -1135,10 +1145,28 @@ struct bpf_prog *bpf_int_jit_compile(struct bpf_prog *prog) prog = tmp; } + jit_data = prog->aux->jit_data; + if (!jit_data) { + jit_data = kzalloc(sizeof(*jit_data), GFP_KERNEL); + if (!jit_data) { + prog = orig_prog; + goto out; + } + prog->aux->jit_data = jit_data; + } + addrs = jit_data->addrs; + if (addrs) { + ctx = jit_data->ctx; + oldproglen = jit_data->proglen; + image = jit_data->image; + header = jit_data->header; + extra_pass = true; + goto skip_init_addrs; + } addrs = kmalloc(prog->len * sizeof(*addrs), GFP_KERNEL); if (!addrs) { prog = orig_prog; - goto out; + goto out_addrs; } /* Before first pass, make a rough estimation of addrs[] @@ -1149,6 +1177,7 @@ struct bpf_prog *bpf_int_jit_compile(struct bpf_prog *prog) addrs[i] = proglen; } ctx.cleanup_addr = proglen; +skip_init_addrs: /* JITed image shrinks with every pass and the loop iterates * until the image stops shrinking. Very large bpf programs @@ -1189,7 +1218,15 @@ struct bpf_prog *bpf_int_jit_compile(struct bpf_prog *prog) if (image) { bpf_flush_icache(header, image + proglen); - bpf_jit_binary_lock_ro(header); + if (!prog->is_func || extra_pass) { + bpf_jit_binary_lock_ro(header); + } else { + jit_data->addrs = addrs; + jit_data->ctx = ctx; + jit_data->proglen = proglen; + jit_data->image = image; + jit_data->header = header; + } prog->bpf_func = (void *)image; prog->jited = 1; prog->jited_len = proglen; @@ -1197,8 +1234,12 @@ struct bpf_prog *bpf_int_jit_compile(struct bpf_prog *prog) prog = orig_prog; } + if (!prog->is_func || extra_pass) { out_addrs: - kfree(addrs); + kfree(addrs); + kfree(jit_data); + prog->aux->jit_data = NULL; + } out: if (tmp_blinded) bpf_jit_prog_release_other(prog, prog == orig_prog ? |