diff options
Diffstat (limited to 'kernel/trace/trace_eprobe.c')
| -rw-r--r-- | kernel/trace/trace_eprobe.c | 365 |
1 files changed, 240 insertions, 125 deletions
diff --git a/kernel/trace/trace_eprobe.c b/kernel/trace/trace_eprobe.c index 928867f527e7..5dd0617e5df6 100644 --- a/kernel/trace/trace_eprobe.c +++ b/kernel/trace/trace_eprobe.c @@ -16,6 +16,7 @@ #include "trace_dynevent.h" #include "trace_probe.h" #include "trace_probe_tmpl.h" +#include "trace_probe_kernel.h" #define EPROBE_EVENT_SYSTEM "eprobes" @@ -26,6 +27,9 @@ struct trace_eprobe { /* tracepoint event */ const char *event_name; + /* filter string for the tracepoint */ + char *filter_str; + struct trace_event_call *event; struct dyn_event devent; @@ -125,6 +129,7 @@ static bool eprobe_dyn_event_match(const char *system, const char *event, * We match the following: * event only - match all eprobes with event name * system and event only - match all system/event probes + * system only - match all system probes * * The below has the above satisfied with more arguments: * @@ -143,7 +148,7 @@ static bool eprobe_dyn_event_match(const char *system, const char *event, return false; /* Must match the event name */ - if (strcmp(trace_probe_name(&ep->tp), event) != 0) + if (event[0] != '\0' && strcmp(trace_probe_name(&ep->tp), event) != 0) return false; /* No arguments match all */ @@ -226,6 +231,7 @@ static int trace_eprobe_tp_arg_update(struct trace_eprobe *ep, int i) struct probe_arg *parg = &ep->tp.args[i]; struct ftrace_event_field *field; struct list_head *head; + int ret = -ENOENT; head = trace_get_fields(ep->event); list_for_each_entry(field, head, link) { @@ -235,14 +241,24 @@ static int trace_eprobe_tp_arg_update(struct trace_eprobe *ep, int i) return 0; } } + + /* + * Argument not found on event. But allow for comm and COMM + * to be used to get the current->comm. + */ + if (strcmp(parg->code->data, "COMM") == 0 || + strcmp(parg->code->data, "comm") == 0) { + parg->code->op = FETCH_OP_COMM; + ret = 0; + } + kfree(parg->code->data); parg->code->data = NULL; - return -ENOENT; + return ret; } static int eprobe_event_define_fields(struct trace_event_call *event_call) { - int ret; struct eprobe_trace_entry_head field; struct trace_probe *tp; @@ -250,8 +266,6 @@ static int eprobe_event_define_fields(struct trace_event_call *event_call) if (WARN_ON_ONCE(!tp)) return -ENOENT; - DEFINE_FIELD(unsigned int, type, FIELD_STRING_TYPE, 0); - return traceprobe_define_arg_fields(event_call, sizeof(field), tp); } @@ -270,7 +284,9 @@ print_eprobe_event(struct trace_iterator *iter, int flags, struct trace_event_call *pevent; struct trace_event *probed_event; struct trace_seq *s = &iter->seq; + struct trace_eprobe *ep; struct trace_probe *tp; + unsigned int type; field = (struct eprobe_trace_entry_head *)iter->ent; tp = trace_probe_primary_from_call( @@ -278,15 +294,18 @@ print_eprobe_event(struct trace_iterator *iter, int flags, if (WARN_ON_ONCE(!tp)) goto out; + ep = container_of(tp, struct trace_eprobe, tp); + type = ep->event->event.type; + trace_seq_printf(s, "%s: (", trace_probe_name(tp)); - probed_event = ftrace_find_event(field->type); + probed_event = ftrace_find_event(type); if (probed_event) { pevent = container_of(probed_event, struct trace_event_call, event); trace_seq_printf(s, "%s.%s", pevent->class->system, trace_event_name(pevent)); } else { - trace_seq_printf(s, "%u", field->type); + trace_seq_printf(s, "%u", type); } trace_seq_putc(s, ')'); @@ -308,6 +327,27 @@ static unsigned long get_event_field(struct fetch_insn *code, void *rec) addr = rec + field->offset; + if (is_string_field(field)) { + switch (field->filter_type) { + case FILTER_DYN_STRING: + val = (unsigned long)(rec + (*(unsigned int *)addr & 0xffff)); + break; + case FILTER_RDYN_STRING: + val = (unsigned long)(addr + (*(unsigned int *)addr & 0xffff)); + break; + case FILTER_STATIC_STRING: + val = (unsigned long)addr; + break; + case FILTER_PTR_STRING: + val = (unsigned long)(*(char *)addr); + break; + default: + WARN_ON_ONCE(1); + return 0; + } + return val; + } + switch (field->size) { case 1: if (field->is_signed) @@ -339,16 +379,38 @@ static unsigned long get_event_field(struct fetch_insn *code, void *rec) static int get_eprobe_size(struct trace_probe *tp, void *rec) { + struct fetch_insn *code; struct probe_arg *arg; int i, len, ret = 0; for (i = 0; i < tp->nr_args; i++) { arg = tp->args + i; - if (unlikely(arg->dynamic)) { + if (arg->dynamic) { unsigned long val; - val = get_event_field(arg->code, rec); - len = process_fetch_insn_bottom(arg->code + 1, val, NULL, NULL); + code = arg->code; + retry: + switch (code->op) { + case FETCH_OP_TP_ARG: + val = get_event_field(code, rec); + break; + case FETCH_OP_IMM: + val = code->immediate; + break; + case FETCH_OP_COMM: + val = (unsigned long)current->comm; + break; + case FETCH_OP_DATA: + val = (unsigned long)code->data; + break; + case FETCH_NOP_SYMBOL: /* Ignore a place holder */ + code++; + goto retry; + default: + continue; + } + code++; + len = process_fetch_insn_bottom(code, val, NULL, NULL); if (len > 0) ret += len; } @@ -366,8 +428,28 @@ process_fetch_insn(struct fetch_insn *code, void *rec, void *dest, { unsigned long val; - val = get_event_field(code, rec); - return process_fetch_insn_bottom(code + 1, val, dest, base); + retry: + switch (code->op) { + case FETCH_OP_TP_ARG: + val = get_event_field(code, rec); + break; + case FETCH_OP_IMM: + val = code->immediate; + break; + case FETCH_OP_COMM: + val = (unsigned long)current->comm; + break; + case FETCH_OP_DATA: + val = (unsigned long)code->data; + break; + case FETCH_NOP_SYMBOL: /* Ignore a place holder */ + code++; + goto retry; + default: + return -EILSEQ; + } + code++; + return process_fetch_insn_bottom(code, val, dest, base); } NOKPROBE_SYMBOL(process_fetch_insn) @@ -375,29 +457,14 @@ NOKPROBE_SYMBOL(process_fetch_insn) static nokprobe_inline int fetch_store_strlen_user(unsigned long addr) { - const void __user *uaddr = (__force const void __user *)addr; - - return strnlen_user_nofault(uaddr, MAX_STRING_SIZE); + return kern_fetch_store_strlen_user(addr); } /* Return the length of string -- including null terminal byte */ static nokprobe_inline int fetch_store_strlen(unsigned long addr) { - int ret, len = 0; - u8 c; - -#ifdef CONFIG_ARCH_HAS_NON_OVERLAPPING_ADDRESS_SPACE - if (addr < TASK_SIZE) - return fetch_store_strlen_user(addr); -#endif - - do { - ret = copy_from_kernel_nofault(&c, (u8 *)addr + len, 1); - len++; - } while (c && ret == 0 && len < MAX_STRING_SIZE); - - return (ret < 0) ? ret : len; + return kern_fetch_store_strlen(addr); } /* @@ -407,21 +474,7 @@ fetch_store_strlen(unsigned long addr) static nokprobe_inline int fetch_store_string_user(unsigned long addr, void *dest, void *base) { - const void __user *uaddr = (__force const void __user *)addr; - int maxlen = get_loc_len(*(u32 *)dest); - void *__dest; - long ret; - - if (unlikely(!maxlen)) - return -ENOMEM; - - __dest = get_loc_data(dest, base); - - ret = strncpy_from_user_nofault(__dest, uaddr, maxlen); - if (ret >= 0) - *(u32 *)dest = make_data_loc(ret, __dest - base); - - return ret; + return kern_fetch_store_string_user(addr, dest, base); } /* @@ -431,29 +484,7 @@ fetch_store_string_user(unsigned long addr, void *dest, void *base) static nokprobe_inline int fetch_store_string(unsigned long addr, void *dest, void *base) { - int maxlen = get_loc_len(*(u32 *)dest); - void *__dest; - long ret; - -#ifdef CONFIG_ARCH_HAS_NON_OVERLAPPING_ADDRESS_SPACE - if ((unsigned long)addr < TASK_SIZE) - return fetch_store_string_user(addr, dest, base); -#endif - - if (unlikely(!maxlen)) - return -ENOMEM; - - __dest = get_loc_data(dest, base); - - /* - * Try to get string again, since the string can be changed while - * probing. - */ - ret = strncpy_from_kernel_nofault(__dest, (void *)addr, maxlen); - if (ret >= 0) - *(u32 *)dest = make_data_loc(ret, __dest - base); - - return ret; + return kern_fetch_store_string(addr, dest, base); } static nokprobe_inline int @@ -489,25 +520,15 @@ __eprobe_trace_func(struct eprobe_data *edata, void *rec) if (trace_trigger_soft_disabled(edata->file)) return; - fbuffer.trace_ctx = tracing_gen_ctx(); - fbuffer.trace_file = edata->file; - dsize = get_eprobe_size(&edata->ep->tp, rec); - fbuffer.regs = NULL; - - fbuffer.event = - trace_event_buffer_lock_reserve(&fbuffer.buffer, edata->file, - call->event.type, - sizeof(*entry) + edata->ep->tp.size + dsize, - fbuffer.trace_ctx); - if (!fbuffer.event) + + entry = trace_event_buffer_reserve(&fbuffer, edata->file, + sizeof(*entry) + edata->ep->tp.size + dsize); + + if (!entry) return; entry = fbuffer.entry = ring_buffer_event_data(fbuffer.event); - if (edata->ep->event) - entry->type = edata->ep->event->event.type; - else - entry->type = 0; store_trace_args(&entry[1], &edata->ep->tp, rec, sizeof(*entry), dsize); trace_event_buffer_commit(&fbuffer); @@ -519,20 +540,17 @@ __eprobe_trace_func(struct eprobe_data *edata, void *rec) * functions are just stubs to fulfill what is needed to use the trigger * infrastructure. */ -static int eprobe_trigger_init(struct event_trigger_ops *ops, - struct event_trigger_data *data) +static int eprobe_trigger_init(struct event_trigger_data *data) { return 0; } -static void eprobe_trigger_free(struct event_trigger_ops *ops, - struct event_trigger_data *data) +static void eprobe_trigger_free(struct event_trigger_data *data) { } static int eprobe_trigger_print(struct seq_file *m, - struct event_trigger_ops *ops, struct event_trigger_data *data) { /* Do not print eprobe event triggers */ @@ -549,29 +567,30 @@ static void eprobe_trigger_func(struct event_trigger_data *data, } static struct event_trigger_ops eprobe_trigger_ops = { - .func = eprobe_trigger_func, + .trigger = eprobe_trigger_func, .print = eprobe_trigger_print, .init = eprobe_trigger_init, .free = eprobe_trigger_free, }; -static int eprobe_trigger_cmd_func(struct event_command *cmd_ops, - struct trace_event_file *file, - char *glob, char *cmd, char *param) +static int eprobe_trigger_cmd_parse(struct event_command *cmd_ops, + struct trace_event_file *file, + char *glob, char *cmd, + char *param_and_filter) { return -1; } -static int eprobe_trigger_reg_func(char *glob, struct event_trigger_ops *ops, - struct event_trigger_data *data, - struct trace_event_file *file) +static int eprobe_trigger_reg_func(char *glob, + struct event_trigger_data *data, + struct trace_event_file *file) { return -1; } -static void eprobe_trigger_unreg_func(char *glob, struct event_trigger_ops *ops, - struct event_trigger_data *data, - struct trace_event_file *file) +static void eprobe_trigger_unreg_func(char *glob, + struct event_trigger_data *data, + struct trace_event_file *file) { } @@ -586,7 +605,7 @@ static struct event_command event_trigger_cmd = { .name = "eprobe", .trigger_type = ETT_EVENT_EPROBE, .flags = EVENT_CMD_FL_NEEDS_REC, - .func = eprobe_trigger_cmd_func, + .parse = eprobe_trigger_cmd_parse, .reg = eprobe_trigger_reg_func, .unreg = eprobe_trigger_unreg_func, .unreg_all = NULL, @@ -598,14 +617,15 @@ static struct event_trigger_data * new_eprobe_trigger(struct trace_eprobe *ep, struct trace_event_file *file) { struct event_trigger_data *trigger; + struct event_filter *filter = NULL; struct eprobe_data *edata; + int ret; edata = kzalloc(sizeof(*edata), GFP_KERNEL); trigger = kzalloc(sizeof(*trigger), GFP_KERNEL); if (!trigger || !edata) { - kfree(edata); - kfree(trigger); - return ERR_PTR(-ENOMEM); + ret = -ENOMEM; + goto error; } trigger->flags = EVENT_TRIGGER_FL_PROBE; @@ -620,13 +640,25 @@ new_eprobe_trigger(struct trace_eprobe *ep, struct trace_event_file *file) trigger->cmd_ops = &event_trigger_cmd; INIT_LIST_HEAD(&trigger->list); - RCU_INIT_POINTER(trigger->filter, NULL); + + if (ep->filter_str) { + ret = create_event_filter(file->tr, file->event_call, + ep->filter_str, false, &filter); + if (ret) + goto error; + } + RCU_INIT_POINTER(trigger->filter, filter); edata->file = file; edata->ep = ep; trigger->private_data = edata; return trigger; +error: + free_event_filter(filter); + kfree(edata); + kfree(trigger); + return ERR_PTR(ret); } static int enable_eprobe(struct trace_eprobe *ep, @@ -658,22 +690,25 @@ static struct trace_event_functions eprobe_funcs = { static int disable_eprobe(struct trace_eprobe *ep, struct trace_array *tr) { - struct event_trigger_data *trigger; + struct event_trigger_data *trigger = NULL, *iter; struct trace_event_file *file; + struct event_filter *filter; struct eprobe_data *edata; file = find_event_file(tr, ep->event_system, ep->event_name); if (!file) return -ENOENT; - list_for_each_entry(trigger, &file->triggers, list) { - if (!(trigger->flags & EVENT_TRIGGER_FL_PROBE)) + list_for_each_entry(iter, &file->triggers, list) { + if (!(iter->flags & EVENT_TRIGGER_FL_PROBE)) continue; - edata = trigger->private_data; - if (edata->ep == ep) + edata = iter->private_data; + if (edata->ep == ep) { + trigger = iter; break; + } } - if (list_entry_is_head(trigger, &file->triggers, list)) + if (!trigger) return -ENODEV; list_del_rcu(&trigger->list); @@ -684,6 +719,10 @@ static int disable_eprobe(struct trace_eprobe *ep, /* Make sure nothing is using the edata or trigger */ tracepoint_synchronize_unregister(); + filter = rcu_access_pointer(trigger->filter); + + if (filter) + free_event_filter(filter); kfree(edata); kfree(trigger); @@ -846,9 +885,66 @@ static int trace_eprobe_tp_update_arg(struct trace_eprobe *ep, const char *argv[ if (ret) return ret; - if (ep->tp.args[i].code->op == FETCH_OP_TP_ARG) + if (ep->tp.args[i].code->op == FETCH_OP_TP_ARG) { ret = trace_eprobe_tp_arg_update(ep, i); + if (ret) + trace_probe_log_err(0, BAD_ATTACH_ARG); + } + + /* Handle symbols "@" */ + if (!ret) + ret = traceprobe_update_arg(&ep->tp.args[i]); + + return ret; +} + +static int trace_eprobe_parse_filter(struct trace_eprobe *ep, int argc, const char *argv[]) +{ + struct event_filter *dummy; + int i, ret, len = 0; + char *p; + + if (argc == 0) { + trace_probe_log_err(0, NO_EP_FILTER); + return -EINVAL; + } + + /* Recover the filter string */ + for (i = 0; i < argc; i++) + len += strlen(argv[i]) + 1; + + ep->filter_str = kzalloc(len, GFP_KERNEL); + if (!ep->filter_str) + return -ENOMEM; + + p = ep->filter_str; + for (i = 0; i < argc; i++) { + ret = snprintf(p, len, "%s ", argv[i]); + if (ret < 0) + goto error; + if (ret > len) { + ret = -E2BIG; + goto error; + } + p += ret; + len -= ret; + } + p[-1] = '\0'; + + /* + * Ensure the filter string can be parsed correctly. Note, this + * filter string is for the original event, not for the eprobe. + */ + ret = create_event_filter(top_trace_array(), ep->event, ep->filter_str, + true, &dummy); + free_event_filter(dummy); + if (ret) + goto error; + return 0; +error: + kfree(ep->filter_str); + ep->filter_str = NULL; return ret; } @@ -856,8 +952,8 @@ static int __trace_eprobe_create(int argc, const char *argv[]) { /* * Argument syntax: - * e[:[GRP/]ENAME] SYSTEM.EVENT [FETCHARGS] - * Fetch args: + * e[:[GRP/][ENAME]] SYSTEM.EVENT [FETCHARGS] [if FILTER] + * Fetch args (no space): * <name>=$<field>[:TYPE] */ const char *event = NULL, *group = EPROBE_EVENT_SYSTEM; @@ -866,8 +962,9 @@ static int __trace_eprobe_create(int argc, const char *argv[]) struct trace_eprobe *ep = NULL; char buf1[MAX_EVENT_NAME_LEN]; char buf2[MAX_EVENT_NAME_LEN]; - int ret = 0; - int i; + char gbuf[MAX_EVENT_NAME_LEN]; + int ret = 0, filter_idx = 0; + int i, filter_cnt; if (argc < 2 || argv[0][0] != 'e') return -ECANCELED; @@ -877,25 +974,33 @@ static int __trace_eprobe_create(int argc, const char *argv[]) event = strchr(&argv[0][1], ':'); if (event) { event++; - ret = traceprobe_parse_event_name(&event, &group, buf1, + ret = traceprobe_parse_event_name(&event, &group, gbuf, event - argv[0]); if (ret) goto parse_error; - } else { - strscpy(buf1, argv[1], MAX_EVENT_NAME_LEN); - sanitize_event_name(buf1); - event = buf1; } - if (!is_good_name(event) || !is_good_name(group)) - goto parse_error; + trace_probe_log_set_index(1); sys_event = argv[1]; - ret = traceprobe_parse_event_name(&sys_event, &sys_name, buf2, - sys_event - argv[1]); - if (ret || !sys_name) - goto parse_error; - if (!is_good_name(sys_event) || !is_good_name(sys_name)) + ret = traceprobe_parse_event_name(&sys_event, &sys_name, buf2, 0); + if (ret || !sys_event || !sys_name) { + trace_probe_log_err(0, NO_EVENT_INFO); goto parse_error; + } + + if (!event) { + strscpy(buf1, sys_event, MAX_EVENT_NAME_LEN); + event = buf1; + } + + for (i = 2; i < argc; i++) { + if (!strcmp(argv[i], "if")) { + filter_idx = i + 1; + filter_cnt = argc - filter_idx; + argc = i; + break; + } + } mutex_lock(&event_mutex); event_call = find_and_get_event(sys_name, sys_event); @@ -904,12 +1009,22 @@ static int __trace_eprobe_create(int argc, const char *argv[]) if (IS_ERR(ep)) { ret = PTR_ERR(ep); + if (ret == -ENODEV) + trace_probe_log_err(0, BAD_ATTACH_EVENT); /* This must return -ENOMEM or missing event, else there is a bug */ WARN_ON_ONCE(ret != -ENOMEM && ret != -ENODEV); ep = NULL; goto error; } + if (filter_idx) { + trace_probe_log_set_index(filter_idx); + ret = trace_eprobe_parse_filter(ep, filter_cnt, argv + filter_idx); + if (ret) + goto parse_error; + } else + ep->filter_str = NULL; + argc -= 2; argv += 2; /* parse arguments */ for (i = 0; i < argc && i < MAX_TRACE_ARGS; i++) { |