diff options
Diffstat (limited to 'kernel/trace/bpf_trace.c')
-rw-r--r-- | kernel/trace/bpf_trace.c | 179 |
1 files changed, 131 insertions, 48 deletions
diff --git a/kernel/trace/bpf_trace.c b/kernel/trace/bpf_trace.c index 19e793aa441a..a010edc37ee0 100644 --- a/kernel/trace/bpf_trace.c +++ b/kernel/trace/bpf_trace.c @@ -83,7 +83,7 @@ unsigned int trace_call_bpf(struct trace_event_call *call, void *ctx) if (in_nmi()) /* not supported yet */ return 1; - preempt_disable(); + cant_sleep(); if (unlikely(__this_cpu_inc_return(bpf_prog_active) != 1)) { /* @@ -115,11 +115,9 @@ unsigned int trace_call_bpf(struct trace_event_call *call, void *ctx) out: __this_cpu_dec(bpf_prog_active); - preempt_enable(); return ret; } -EXPORT_SYMBOL_GPL(trace_call_bpf); #ifdef CONFIG_BPF_KPROBE_OVERRIDE BPF_CALL_2(bpf_override_return, struct pt_regs *, regs, unsigned long, rc) @@ -325,17 +323,15 @@ static const struct bpf_func_proto *bpf_get_probe_write_proto(void) /* * Only limited trace_printk() conversion specifiers allowed: - * %d %i %u %x %ld %li %lu %lx %lld %lli %llu %llx %p %s + * %d %i %u %x %ld %li %lu %lx %lld %lli %llu %llx %p %pks %pus %s */ BPF_CALL_5(bpf_trace_printk, char *, fmt, u32, fmt_size, u64, arg1, u64, arg2, u64, arg3) { + int i, mod[3] = {}, fmt_cnt = 0; + char buf[64], fmt_ptype; + void *unsafe_ptr = NULL; bool str_seen = false; - int mod[3] = {}; - int fmt_cnt = 0; - u64 unsafe_addr; - char buf[64]; - int i; /* * bpf_check()->check_func_arg()->check_stack_boundary() @@ -361,40 +357,71 @@ BPF_CALL_5(bpf_trace_printk, char *, fmt, u32, fmt_size, u64, arg1, if (fmt[i] == 'l') { mod[fmt_cnt]++; i++; - } else if (fmt[i] == 'p' || fmt[i] == 's') { + } else if (fmt[i] == 'p') { mod[fmt_cnt]++; + if ((fmt[i + 1] == 'k' || + fmt[i + 1] == 'u') && + fmt[i + 2] == 's') { + fmt_ptype = fmt[i + 1]; + i += 2; + goto fmt_str; + } + /* disallow any further format extensions */ if (fmt[i + 1] != 0 && !isspace(fmt[i + 1]) && !ispunct(fmt[i + 1])) return -EINVAL; - fmt_cnt++; - if (fmt[i] == 's') { - if (str_seen) - /* allow only one '%s' per fmt string */ - return -EINVAL; - str_seen = true; - - switch (fmt_cnt) { - case 1: - unsafe_addr = arg1; - arg1 = (long) buf; - break; - case 2: - unsafe_addr = arg2; - arg2 = (long) buf; - break; - case 3: - unsafe_addr = arg3; - arg3 = (long) buf; - break; - } - buf[0] = 0; - strncpy_from_unsafe(buf, - (void *) (long) unsafe_addr, + + goto fmt_next; + } else if (fmt[i] == 's') { + mod[fmt_cnt]++; + fmt_ptype = fmt[i]; +fmt_str: + if (str_seen) + /* allow only one '%s' per fmt string */ + return -EINVAL; + str_seen = true; + + if (fmt[i + 1] != 0 && + !isspace(fmt[i + 1]) && + !ispunct(fmt[i + 1])) + return -EINVAL; + + switch (fmt_cnt) { + case 0: + unsafe_ptr = (void *)(long)arg1; + arg1 = (long)buf; + break; + case 1: + unsafe_ptr = (void *)(long)arg2; + arg2 = (long)buf; + break; + case 2: + unsafe_ptr = (void *)(long)arg3; + arg3 = (long)buf; + break; + } + + buf[0] = 0; + switch (fmt_ptype) { + case 's': +#ifdef CONFIG_ARCH_HAS_NON_OVERLAPPING_ADDRESS_SPACE + strncpy_from_unsafe(buf, unsafe_ptr, sizeof(buf)); + break; +#endif + case 'k': + strncpy_from_unsafe_strict(buf, unsafe_ptr, + sizeof(buf)); + break; + case 'u': + strncpy_from_unsafe_user(buf, + (__force void __user *)unsafe_ptr, + sizeof(buf)); + break; } - continue; + goto fmt_next; } if (fmt[i] == 'l') { @@ -405,6 +432,7 @@ BPF_CALL_5(bpf_trace_printk, char *, fmt, u32, fmt_size, u64, arg1, if (fmt[i] != 'i' && fmt[i] != 'd' && fmt[i] != 'u' && fmt[i] != 'x') return -EINVAL; +fmt_next: fmt_cnt++; } @@ -732,7 +760,7 @@ static int bpf_send_signal_common(u32 sig, enum pid_type type) if (unlikely(!nmi_uaccess_okay())) return -EPERM; - if (in_nmi()) { + if (irqs_disabled()) { /* Do an early check on signal validity. Otherwise, * the error is lost in deferred irq_work. */ @@ -781,8 +809,8 @@ static const struct bpf_func_proto bpf_send_signal_thread_proto = { .arg1_type = ARG_ANYTHING, }; -static const struct bpf_func_proto * -tracing_func_proto(enum bpf_func_id func_id, const struct bpf_prog *prog) +const struct bpf_func_proto * +bpf_tracing_func_proto(enum bpf_func_id func_id, const struct bpf_prog *prog) { switch (func_id) { case BPF_FUNC_map_lookup_elem: @@ -827,14 +855,16 @@ tracing_func_proto(enum bpf_func_id func_id, const struct bpf_prog *prog) return &bpf_probe_read_user_proto; case BPF_FUNC_probe_read_kernel: return &bpf_probe_read_kernel_proto; - case BPF_FUNC_probe_read: - return &bpf_probe_read_compat_proto; case BPF_FUNC_probe_read_user_str: return &bpf_probe_read_user_str_proto; case BPF_FUNC_probe_read_kernel_str: return &bpf_probe_read_kernel_str_proto; +#ifdef CONFIG_ARCH_HAS_NON_OVERLAPPING_ADDRESS_SPACE + case BPF_FUNC_probe_read: + return &bpf_probe_read_compat_proto; case BPF_FUNC_probe_read_str: return &bpf_probe_read_compat_str_proto; +#endif #ifdef CONFIG_CGROUPS case BPF_FUNC_get_current_cgroup_id: return &bpf_get_current_cgroup_id_proto; @@ -843,6 +873,10 @@ tracing_func_proto(enum bpf_func_id func_id, const struct bpf_prog *prog) return &bpf_send_signal_proto; case BPF_FUNC_send_signal_thread: return &bpf_send_signal_thread_proto; + case BPF_FUNC_perf_event_read_value: + return &bpf_perf_event_read_value_proto; + case BPF_FUNC_get_ns_current_pid_tgid: + return &bpf_get_ns_current_pid_tgid_proto; default: return NULL; } @@ -858,14 +892,12 @@ kprobe_prog_func_proto(enum bpf_func_id func_id, const struct bpf_prog *prog) return &bpf_get_stackid_proto; case BPF_FUNC_get_stack: return &bpf_get_stack_proto; - case BPF_FUNC_perf_event_read_value: - return &bpf_perf_event_read_value_proto; #ifdef CONFIG_BPF_KPROBE_OVERRIDE case BPF_FUNC_override_return: return &bpf_override_return_proto; #endif default: - return tracing_func_proto(func_id, prog); + return bpf_tracing_func_proto(func_id, prog); } } @@ -975,7 +1007,7 @@ tp_prog_func_proto(enum bpf_func_id func_id, const struct bpf_prog *prog) case BPF_FUNC_get_stack: return &bpf_get_stack_proto_tp; default: - return tracing_func_proto(func_id, prog); + return bpf_tracing_func_proto(func_id, prog); } } @@ -1028,6 +1060,45 @@ static const struct bpf_func_proto bpf_perf_prog_read_value_proto = { .arg3_type = ARG_CONST_SIZE, }; +BPF_CALL_4(bpf_read_branch_records, struct bpf_perf_event_data_kern *, ctx, + void *, buf, u32, size, u64, flags) +{ +#ifndef CONFIG_X86 + return -ENOENT; +#else + static const u32 br_entry_size = sizeof(struct perf_branch_entry); + struct perf_branch_stack *br_stack = ctx->data->br_stack; + u32 to_copy; + + if (unlikely(flags & ~BPF_F_GET_BRANCH_RECORDS_SIZE)) + return -EINVAL; + + if (unlikely(!br_stack)) + return -EINVAL; + + if (flags & BPF_F_GET_BRANCH_RECORDS_SIZE) + return br_stack->nr * br_entry_size; + + if (!buf || (size % br_entry_size != 0)) + return -EINVAL; + + to_copy = min_t(u32, br_stack->nr * br_entry_size, size); + memcpy(buf, br_stack->entries, to_copy); + + return to_copy; +#endif +} + +static const struct bpf_func_proto bpf_read_branch_records_proto = { + .func = bpf_read_branch_records, + .gpl_only = true, + .ret_type = RET_INTEGER, + .arg1_type = ARG_PTR_TO_CTX, + .arg2_type = ARG_PTR_TO_MEM_OR_NULL, + .arg3_type = ARG_CONST_SIZE_OR_ZERO, + .arg4_type = ARG_ANYTHING, +}; + static const struct bpf_func_proto * pe_prog_func_proto(enum bpf_func_id func_id, const struct bpf_prog *prog) { @@ -1040,8 +1111,10 @@ pe_prog_func_proto(enum bpf_func_id func_id, const struct bpf_prog *prog) return &bpf_get_stack_proto_tp; case BPF_FUNC_perf_prog_read_value: return &bpf_perf_prog_read_value_proto; + case BPF_FUNC_read_branch_records: + return &bpf_read_branch_records_proto; default: - return tracing_func_proto(func_id, prog); + return bpf_tracing_func_proto(func_id, prog); } } @@ -1104,6 +1177,7 @@ static const struct bpf_func_proto bpf_perf_event_output_proto_raw_tp = { }; extern const struct bpf_func_proto bpf_skb_output_proto; +extern const struct bpf_func_proto bpf_xdp_output_proto; BPF_CALL_3(bpf_get_stackid_raw_tp, struct bpf_raw_tracepoint_args *, args, struct bpf_map *, map, u64, flags) @@ -1168,7 +1242,7 @@ raw_tp_prog_func_proto(enum bpf_func_id func_id, const struct bpf_prog *prog) case BPF_FUNC_get_stack: return &bpf_get_stack_proto_raw_tp; default: - return tracing_func_proto(func_id, prog); + return bpf_tracing_func_proto(func_id, prog); } } @@ -1179,6 +1253,8 @@ tracing_prog_func_proto(enum bpf_func_id func_id, const struct bpf_prog *prog) #ifdef CONFIG_NET case BPF_FUNC_skb_output: return &bpf_skb_output_proto; + case BPF_FUNC_xdp_output: + return &bpf_xdp_output_proto; #endif default: return raw_tp_prog_func_proto(func_id, prog); @@ -1213,6 +1289,13 @@ static bool tracing_prog_is_valid_access(int off, int size, return btf_ctx_access(off, size, type, prog, info); } +int __weak bpf_prog_test_run_tracing(struct bpf_prog *prog, + const union bpf_attr *kattr, + union bpf_attr __user *uattr) +{ + return -ENOTSUPP; +} + const struct bpf_verifier_ops raw_tracepoint_verifier_ops = { .get_func_proto = raw_tp_prog_func_proto, .is_valid_access = raw_tp_prog_is_valid_access, @@ -1227,6 +1310,7 @@ const struct bpf_verifier_ops tracing_verifier_ops = { }; const struct bpf_prog_ops tracing_prog_ops = { + .test_run = bpf_prog_test_run_tracing, }; static bool raw_tp_writable_prog_is_valid_access(int off, int size, @@ -1475,10 +1559,9 @@ void bpf_put_raw_tracepoint(struct bpf_raw_event_map *btp) static __always_inline void __bpf_trace_run(struct bpf_prog *prog, u64 *args) { + cant_sleep(); rcu_read_lock(); - preempt_disable(); (void) BPF_PROG_RUN(prog, args); - preempt_enable(); rcu_read_unlock(); } |