forked from Qortal/Brooklyn
You can not select more than 25 topics
Topics must start with a letter or number, can include dashes ('-') and can be up to 35 characters long.
1208 lines
28 KiB
1208 lines
28 KiB
// SPDX-License-Identifier: GPL-2.0 |
|
/* |
|
* Common code for probe-based Dynamic events. |
|
* |
|
* This code was copied from kernel/trace/trace_kprobe.c written by |
|
* Masami Hiramatsu <[email protected]> |
|
* |
|
* Updates to make this generic: |
|
* Copyright (C) IBM Corporation, 2010-2011 |
|
* Author: Srikar Dronamraju |
|
*/ |
|
#define pr_fmt(fmt) "trace_probe: " fmt |
|
|
|
#include "trace_probe.h" |
|
|
|
#undef C |
|
#define C(a, b) b |
|
|
|
static const char *trace_probe_err_text[] = { ERRORS }; |
|
|
|
static const char *reserved_field_names[] = { |
|
"common_type", |
|
"common_flags", |
|
"common_preempt_count", |
|
"common_pid", |
|
"common_tgid", |
|
FIELD_STRING_IP, |
|
FIELD_STRING_RETIP, |
|
FIELD_STRING_FUNC, |
|
}; |
|
|
|
/* Printing in basic type function template */ |
|
#define DEFINE_BASIC_PRINT_TYPE_FUNC(tname, type, fmt) \ |
|
int PRINT_TYPE_FUNC_NAME(tname)(struct trace_seq *s, void *data, void *ent)\ |
|
{ \ |
|
trace_seq_printf(s, fmt, *(type *)data); \ |
|
return !trace_seq_has_overflowed(s); \ |
|
} \ |
|
const char PRINT_TYPE_FMT_NAME(tname)[] = fmt; |
|
|
|
DEFINE_BASIC_PRINT_TYPE_FUNC(u8, u8, "%u") |
|
DEFINE_BASIC_PRINT_TYPE_FUNC(u16, u16, "%u") |
|
DEFINE_BASIC_PRINT_TYPE_FUNC(u32, u32, "%u") |
|
DEFINE_BASIC_PRINT_TYPE_FUNC(u64, u64, "%Lu") |
|
DEFINE_BASIC_PRINT_TYPE_FUNC(s8, s8, "%d") |
|
DEFINE_BASIC_PRINT_TYPE_FUNC(s16, s16, "%d") |
|
DEFINE_BASIC_PRINT_TYPE_FUNC(s32, s32, "%d") |
|
DEFINE_BASIC_PRINT_TYPE_FUNC(s64, s64, "%Ld") |
|
DEFINE_BASIC_PRINT_TYPE_FUNC(x8, u8, "0x%x") |
|
DEFINE_BASIC_PRINT_TYPE_FUNC(x16, u16, "0x%x") |
|
DEFINE_BASIC_PRINT_TYPE_FUNC(x32, u32, "0x%x") |
|
DEFINE_BASIC_PRINT_TYPE_FUNC(x64, u64, "0x%Lx") |
|
|
|
int PRINT_TYPE_FUNC_NAME(symbol)(struct trace_seq *s, void *data, void *ent) |
|
{ |
|
trace_seq_printf(s, "%pS", (void *)*(unsigned long *)data); |
|
return !trace_seq_has_overflowed(s); |
|
} |
|
const char PRINT_TYPE_FMT_NAME(symbol)[] = "%pS"; |
|
|
|
/* Print type function for string type */ |
|
int PRINT_TYPE_FUNC_NAME(string)(struct trace_seq *s, void *data, void *ent) |
|
{ |
|
int len = *(u32 *)data >> 16; |
|
|
|
if (!len) |
|
trace_seq_puts(s, "(fault)"); |
|
else |
|
trace_seq_printf(s, "\"%s\"", |
|
(const char *)get_loc_data(data, ent)); |
|
return !trace_seq_has_overflowed(s); |
|
} |
|
|
|
const char PRINT_TYPE_FMT_NAME(string)[] = "\\\"%s\\\""; |
|
|
|
/* Fetch type information table */ |
|
static const struct fetch_type probe_fetch_types[] = { |
|
/* Special types */ |
|
__ASSIGN_FETCH_TYPE("string", string, string, sizeof(u32), 1, |
|
"__data_loc char[]"), |
|
__ASSIGN_FETCH_TYPE("ustring", string, string, sizeof(u32), 1, |
|
"__data_loc char[]"), |
|
/* Basic types */ |
|
ASSIGN_FETCH_TYPE(u8, u8, 0), |
|
ASSIGN_FETCH_TYPE(u16, u16, 0), |
|
ASSIGN_FETCH_TYPE(u32, u32, 0), |
|
ASSIGN_FETCH_TYPE(u64, u64, 0), |
|
ASSIGN_FETCH_TYPE(s8, u8, 1), |
|
ASSIGN_FETCH_TYPE(s16, u16, 1), |
|
ASSIGN_FETCH_TYPE(s32, u32, 1), |
|
ASSIGN_FETCH_TYPE(s64, u64, 1), |
|
ASSIGN_FETCH_TYPE_ALIAS(x8, u8, u8, 0), |
|
ASSIGN_FETCH_TYPE_ALIAS(x16, u16, u16, 0), |
|
ASSIGN_FETCH_TYPE_ALIAS(x32, u32, u32, 0), |
|
ASSIGN_FETCH_TYPE_ALIAS(x64, u64, u64, 0), |
|
ASSIGN_FETCH_TYPE_ALIAS(symbol, ADDR_FETCH_TYPE, ADDR_FETCH_TYPE, 0), |
|
|
|
ASSIGN_FETCH_TYPE_END |
|
}; |
|
|
|
static const struct fetch_type *find_fetch_type(const char *type) |
|
{ |
|
int i; |
|
|
|
if (!type) |
|
type = DEFAULT_FETCH_TYPE_STR; |
|
|
|
/* Special case: bitfield */ |
|
if (*type == 'b') { |
|
unsigned long bs; |
|
|
|
type = strchr(type, '/'); |
|
if (!type) |
|
goto fail; |
|
|
|
type++; |
|
if (kstrtoul(type, 0, &bs)) |
|
goto fail; |
|
|
|
switch (bs) { |
|
case 8: |
|
return find_fetch_type("u8"); |
|
case 16: |
|
return find_fetch_type("u16"); |
|
case 32: |
|
return find_fetch_type("u32"); |
|
case 64: |
|
return find_fetch_type("u64"); |
|
default: |
|
goto fail; |
|
} |
|
} |
|
|
|
for (i = 0; probe_fetch_types[i].name; i++) { |
|
if (strcmp(type, probe_fetch_types[i].name) == 0) |
|
return &probe_fetch_types[i]; |
|
} |
|
|
|
fail: |
|
return NULL; |
|
} |
|
|
|
static struct trace_probe_log trace_probe_log; |
|
|
|
void trace_probe_log_init(const char *subsystem, int argc, const char **argv) |
|
{ |
|
trace_probe_log.subsystem = subsystem; |
|
trace_probe_log.argc = argc; |
|
trace_probe_log.argv = argv; |
|
trace_probe_log.index = 0; |
|
} |
|
|
|
void trace_probe_log_clear(void) |
|
{ |
|
memset(&trace_probe_log, 0, sizeof(trace_probe_log)); |
|
} |
|
|
|
void trace_probe_log_set_index(int index) |
|
{ |
|
trace_probe_log.index = index; |
|
} |
|
|
|
void __trace_probe_log_err(int offset, int err_type) |
|
{ |
|
char *command, *p; |
|
int i, len = 0, pos = 0; |
|
|
|
if (!trace_probe_log.argv) |
|
return; |
|
|
|
/* Recalculate the length and allocate buffer */ |
|
for (i = 0; i < trace_probe_log.argc; i++) { |
|
if (i == trace_probe_log.index) |
|
pos = len; |
|
len += strlen(trace_probe_log.argv[i]) + 1; |
|
} |
|
command = kzalloc(len, GFP_KERNEL); |
|
if (!command) |
|
return; |
|
|
|
if (trace_probe_log.index >= trace_probe_log.argc) { |
|
/** |
|
* Set the error position is next to the last arg + space. |
|
* Note that len includes the terminal null and the cursor |
|
* appears at pos + 1. |
|
*/ |
|
pos = len; |
|
offset = 0; |
|
} |
|
|
|
/* And make a command string from argv array */ |
|
p = command; |
|
for (i = 0; i < trace_probe_log.argc; i++) { |
|
len = strlen(trace_probe_log.argv[i]); |
|
strcpy(p, trace_probe_log.argv[i]); |
|
p[len] = ' '; |
|
p += len + 1; |
|
} |
|
*(p - 1) = '\0'; |
|
|
|
tracing_log_err(NULL, trace_probe_log.subsystem, command, |
|
trace_probe_err_text, err_type, pos + offset); |
|
|
|
kfree(command); |
|
} |
|
|
|
/* Split symbol and offset. */ |
|
int traceprobe_split_symbol_offset(char *symbol, long *offset) |
|
{ |
|
char *tmp; |
|
int ret; |
|
|
|
if (!offset) |
|
return -EINVAL; |
|
|
|
tmp = strpbrk(symbol, "+-"); |
|
if (tmp) { |
|
ret = kstrtol(tmp, 0, offset); |
|
if (ret) |
|
return ret; |
|
*tmp = '\0'; |
|
} else |
|
*offset = 0; |
|
|
|
return 0; |
|
} |
|
|
|
/* @buf must has MAX_EVENT_NAME_LEN size */ |
|
int traceprobe_parse_event_name(const char **pevent, const char **pgroup, |
|
char *buf, int offset) |
|
{ |
|
const char *slash, *event = *pevent; |
|
int len; |
|
|
|
slash = strchr(event, '/'); |
|
if (!slash) |
|
slash = strchr(event, '.'); |
|
|
|
if (slash) { |
|
if (slash == event) { |
|
trace_probe_log_err(offset, NO_GROUP_NAME); |
|
return -EINVAL; |
|
} |
|
if (slash - event + 1 > MAX_EVENT_NAME_LEN) { |
|
trace_probe_log_err(offset, GROUP_TOO_LONG); |
|
return -EINVAL; |
|
} |
|
strlcpy(buf, event, slash - event + 1); |
|
if (!is_good_name(buf)) { |
|
trace_probe_log_err(offset, BAD_GROUP_NAME); |
|
return -EINVAL; |
|
} |
|
*pgroup = buf; |
|
*pevent = slash + 1; |
|
offset += slash - event + 1; |
|
event = *pevent; |
|
} |
|
len = strlen(event); |
|
if (len == 0) { |
|
trace_probe_log_err(offset, NO_EVENT_NAME); |
|
return -EINVAL; |
|
} else if (len > MAX_EVENT_NAME_LEN) { |
|
trace_probe_log_err(offset, EVENT_TOO_LONG); |
|
return -EINVAL; |
|
} |
|
if (!is_good_name(event)) { |
|
trace_probe_log_err(offset, BAD_EVENT_NAME); |
|
return -EINVAL; |
|
} |
|
return 0; |
|
} |
|
|
|
#define PARAM_MAX_STACK (THREAD_SIZE / sizeof(unsigned long)) |
|
|
|
static int parse_probe_vars(char *arg, const struct fetch_type *t, |
|
struct fetch_insn *code, unsigned int flags, int offs) |
|
{ |
|
unsigned long param; |
|
int ret = 0; |
|
int len; |
|
|
|
if (strcmp(arg, "retval") == 0) { |
|
if (flags & TPARG_FL_RETURN) { |
|
code->op = FETCH_OP_RETVAL; |
|
} else { |
|
trace_probe_log_err(offs, RETVAL_ON_PROBE); |
|
ret = -EINVAL; |
|
} |
|
} else if ((len = str_has_prefix(arg, "stack"))) { |
|
if (arg[len] == '\0') { |
|
code->op = FETCH_OP_STACKP; |
|
} else if (isdigit(arg[len])) { |
|
ret = kstrtoul(arg + len, 10, ¶m); |
|
if (ret) { |
|
goto inval_var; |
|
} else if ((flags & TPARG_FL_KERNEL) && |
|
param > PARAM_MAX_STACK) { |
|
trace_probe_log_err(offs, BAD_STACK_NUM); |
|
ret = -EINVAL; |
|
} else { |
|
code->op = FETCH_OP_STACK; |
|
code->param = (unsigned int)param; |
|
} |
|
} else |
|
goto inval_var; |
|
} else if (strcmp(arg, "comm") == 0) { |
|
code->op = FETCH_OP_COMM; |
|
#ifdef CONFIG_HAVE_FUNCTION_ARG_ACCESS_API |
|
} else if (((flags & TPARG_FL_MASK) == |
|
(TPARG_FL_KERNEL | TPARG_FL_FENTRY)) && |
|
(len = str_has_prefix(arg, "arg"))) { |
|
ret = kstrtoul(arg + len, 10, ¶m); |
|
if (ret) { |
|
goto inval_var; |
|
} else if (!param || param > PARAM_MAX_STACK) { |
|
trace_probe_log_err(offs, BAD_ARG_NUM); |
|
return -EINVAL; |
|
} |
|
code->op = FETCH_OP_ARG; |
|
code->param = (unsigned int)param - 1; |
|
#endif |
|
} else if (flags & TPARG_FL_TPOINT) { |
|
if (code->data) |
|
return -EFAULT; |
|
code->data = kstrdup(arg, GFP_KERNEL); |
|
if (!code->data) |
|
return -ENOMEM; |
|
code->op = FETCH_OP_TP_ARG; |
|
} else |
|
goto inval_var; |
|
|
|
return ret; |
|
|
|
inval_var: |
|
trace_probe_log_err(offs, BAD_VAR); |
|
return -EINVAL; |
|
} |
|
|
|
static int str_to_immediate(char *str, unsigned long *imm) |
|
{ |
|
if (isdigit(str[0])) |
|
return kstrtoul(str, 0, imm); |
|
else if (str[0] == '-') |
|
return kstrtol(str, 0, (long *)imm); |
|
else if (str[0] == '+') |
|
return kstrtol(str + 1, 0, (long *)imm); |
|
return -EINVAL; |
|
} |
|
|
|
static int __parse_imm_string(char *str, char **pbuf, int offs) |
|
{ |
|
size_t len = strlen(str); |
|
|
|
if (str[len - 1] != '"') { |
|
trace_probe_log_err(offs + len, IMMSTR_NO_CLOSE); |
|
return -EINVAL; |
|
} |
|
*pbuf = kstrndup(str, len - 1, GFP_KERNEL); |
|
return 0; |
|
} |
|
|
|
/* Recursive argument parser */ |
|
static int |
|
parse_probe_arg(char *arg, const struct fetch_type *type, |
|
struct fetch_insn **pcode, struct fetch_insn *end, |
|
unsigned int flags, int offs) |
|
{ |
|
struct fetch_insn *code = *pcode; |
|
unsigned long param; |
|
int deref = FETCH_OP_DEREF; |
|
long offset = 0; |
|
char *tmp; |
|
int ret = 0; |
|
|
|
switch (arg[0]) { |
|
case '$': |
|
ret = parse_probe_vars(arg + 1, type, code, flags, offs); |
|
break; |
|
|
|
case '%': /* named register */ |
|
ret = regs_query_register_offset(arg + 1); |
|
if (ret >= 0) { |
|
code->op = FETCH_OP_REG; |
|
code->param = (unsigned int)ret; |
|
ret = 0; |
|
} else |
|
trace_probe_log_err(offs, BAD_REG_NAME); |
|
break; |
|
|
|
case '@': /* memory, file-offset or symbol */ |
|
if (isdigit(arg[1])) { |
|
ret = kstrtoul(arg + 1, 0, ¶m); |
|
if (ret) { |
|
trace_probe_log_err(offs, BAD_MEM_ADDR); |
|
break; |
|
} |
|
/* load address */ |
|
code->op = FETCH_OP_IMM; |
|
code->immediate = param; |
|
} else if (arg[1] == '+') { |
|
/* kprobes don't support file offsets */ |
|
if (flags & TPARG_FL_KERNEL) { |
|
trace_probe_log_err(offs, FILE_ON_KPROBE); |
|
return -EINVAL; |
|
} |
|
ret = kstrtol(arg + 2, 0, &offset); |
|
if (ret) { |
|
trace_probe_log_err(offs, BAD_FILE_OFFS); |
|
break; |
|
} |
|
|
|
code->op = FETCH_OP_FOFFS; |
|
code->immediate = (unsigned long)offset; // imm64? |
|
} else { |
|
/* uprobes don't support symbols */ |
|
if (!(flags & TPARG_FL_KERNEL)) { |
|
trace_probe_log_err(offs, SYM_ON_UPROBE); |
|
return -EINVAL; |
|
} |
|
/* Preserve symbol for updating */ |
|
code->op = FETCH_NOP_SYMBOL; |
|
code->data = kstrdup(arg + 1, GFP_KERNEL); |
|
if (!code->data) |
|
return -ENOMEM; |
|
if (++code == end) { |
|
trace_probe_log_err(offs, TOO_MANY_OPS); |
|
return -EINVAL; |
|
} |
|
code->op = FETCH_OP_IMM; |
|
code->immediate = 0; |
|
} |
|
/* These are fetching from memory */ |
|
if (++code == end) { |
|
trace_probe_log_err(offs, TOO_MANY_OPS); |
|
return -EINVAL; |
|
} |
|
*pcode = code; |
|
code->op = FETCH_OP_DEREF; |
|
code->offset = offset; |
|
break; |
|
|
|
case '+': /* deref memory */ |
|
case '-': |
|
if (arg[1] == 'u') { |
|
deref = FETCH_OP_UDEREF; |
|
arg[1] = arg[0]; |
|
arg++; |
|
} |
|
if (arg[0] == '+') |
|
arg++; /* Skip '+', because kstrtol() rejects it. */ |
|
tmp = strchr(arg, '('); |
|
if (!tmp) { |
|
trace_probe_log_err(offs, DEREF_NEED_BRACE); |
|
return -EINVAL; |
|
} |
|
*tmp = '\0'; |
|
ret = kstrtol(arg, 0, &offset); |
|
if (ret) { |
|
trace_probe_log_err(offs, BAD_DEREF_OFFS); |
|
break; |
|
} |
|
offs += (tmp + 1 - arg) + (arg[0] != '-' ? 1 : 0); |
|
arg = tmp + 1; |
|
tmp = strrchr(arg, ')'); |
|
if (!tmp) { |
|
trace_probe_log_err(offs + strlen(arg), |
|
DEREF_OPEN_BRACE); |
|
return -EINVAL; |
|
} else { |
|
const struct fetch_type *t2 = find_fetch_type(NULL); |
|
|
|
*tmp = '\0'; |
|
ret = parse_probe_arg(arg, t2, &code, end, flags, offs); |
|
if (ret) |
|
break; |
|
if (code->op == FETCH_OP_COMM || |
|
code->op == FETCH_OP_DATA) { |
|
trace_probe_log_err(offs, COMM_CANT_DEREF); |
|
return -EINVAL; |
|
} |
|
if (++code == end) { |
|
trace_probe_log_err(offs, TOO_MANY_OPS); |
|
return -EINVAL; |
|
} |
|
*pcode = code; |
|
|
|
code->op = deref; |
|
code->offset = offset; |
|
} |
|
break; |
|
case '\\': /* Immediate value */ |
|
if (arg[1] == '"') { /* Immediate string */ |
|
ret = __parse_imm_string(arg + 2, &tmp, offs + 2); |
|
if (ret) |
|
break; |
|
code->op = FETCH_OP_DATA; |
|
code->data = tmp; |
|
} else { |
|
ret = str_to_immediate(arg + 1, &code->immediate); |
|
if (ret) |
|
trace_probe_log_err(offs + 1, BAD_IMM); |
|
else |
|
code->op = FETCH_OP_IMM; |
|
} |
|
break; |
|
} |
|
if (!ret && code->op == FETCH_OP_NOP) { |
|
/* Parsed, but do not find fetch method */ |
|
trace_probe_log_err(offs, BAD_FETCH_ARG); |
|
ret = -EINVAL; |
|
} |
|
return ret; |
|
} |
|
|
|
#define BYTES_TO_BITS(nb) ((BITS_PER_LONG * (nb)) / sizeof(long)) |
|
|
|
/* Bitfield type needs to be parsed into a fetch function */ |
|
static int __parse_bitfield_probe_arg(const char *bf, |
|
const struct fetch_type *t, |
|
struct fetch_insn **pcode) |
|
{ |
|
struct fetch_insn *code = *pcode; |
|
unsigned long bw, bo; |
|
char *tail; |
|
|
|
if (*bf != 'b') |
|
return 0; |
|
|
|
bw = simple_strtoul(bf + 1, &tail, 0); /* Use simple one */ |
|
|
|
if (bw == 0 || *tail != '@') |
|
return -EINVAL; |
|
|
|
bf = tail + 1; |
|
bo = simple_strtoul(bf, &tail, 0); |
|
|
|
if (tail == bf || *tail != '/') |
|
return -EINVAL; |
|
code++; |
|
if (code->op != FETCH_OP_NOP) |
|
return -EINVAL; |
|
*pcode = code; |
|
|
|
code->op = FETCH_OP_MOD_BF; |
|
code->lshift = BYTES_TO_BITS(t->size) - (bw + bo); |
|
code->rshift = BYTES_TO_BITS(t->size) - bw; |
|
code->basesize = t->size; |
|
|
|
return (BYTES_TO_BITS(t->size) < (bw + bo)) ? -EINVAL : 0; |
|
} |
|
|
|
/* String length checking wrapper */ |
|
static int traceprobe_parse_probe_arg_body(const char *argv, ssize_t *size, |
|
struct probe_arg *parg, unsigned int flags, int offset) |
|
{ |
|
struct fetch_insn *code, *scode, *tmp = NULL; |
|
char *t, *t2, *t3; |
|
char *arg; |
|
int ret, len; |
|
|
|
arg = kstrdup(argv, GFP_KERNEL); |
|
if (!arg) |
|
return -ENOMEM; |
|
|
|
ret = -EINVAL; |
|
len = strlen(arg); |
|
if (len > MAX_ARGSTR_LEN) { |
|
trace_probe_log_err(offset, ARG_TOO_LONG); |
|
goto out; |
|
} else if (len == 0) { |
|
trace_probe_log_err(offset, NO_ARG_BODY); |
|
goto out; |
|
} |
|
|
|
ret = -ENOMEM; |
|
parg->comm = kstrdup(arg, GFP_KERNEL); |
|
if (!parg->comm) |
|
goto out; |
|
|
|
ret = -EINVAL; |
|
t = strchr(arg, ':'); |
|
if (t) { |
|
*t = '\0'; |
|
t2 = strchr(++t, '['); |
|
if (t2) { |
|
*t2++ = '\0'; |
|
t3 = strchr(t2, ']'); |
|
if (!t3) { |
|
offset += t2 + strlen(t2) - arg; |
|
trace_probe_log_err(offset, |
|
ARRAY_NO_CLOSE); |
|
goto out; |
|
} else if (t3[1] != '\0') { |
|
trace_probe_log_err(offset + t3 + 1 - arg, |
|
BAD_ARRAY_SUFFIX); |
|
goto out; |
|
} |
|
*t3 = '\0'; |
|
if (kstrtouint(t2, 0, &parg->count) || !parg->count) { |
|
trace_probe_log_err(offset + t2 - arg, |
|
BAD_ARRAY_NUM); |
|
goto out; |
|
} |
|
if (parg->count > MAX_ARRAY_LEN) { |
|
trace_probe_log_err(offset + t2 - arg, |
|
ARRAY_TOO_BIG); |
|
goto out; |
|
} |
|
} |
|
} |
|
|
|
/* |
|
* Since $comm and immediate string can not be dereferenced, |
|
* we can find those by strcmp. |
|
*/ |
|
if (strcmp(arg, "$comm") == 0 || strncmp(arg, "\\\"", 2) == 0) { |
|
/* The type of $comm must be "string", and not an array. */ |
|
if (parg->count || (t && strcmp(t, "string"))) |
|
goto out; |
|
parg->type = find_fetch_type("string"); |
|
} else |
|
parg->type = find_fetch_type(t); |
|
if (!parg->type) { |
|
trace_probe_log_err(offset + (t ? (t - arg) : 0), BAD_TYPE); |
|
goto out; |
|
} |
|
parg->offset = *size; |
|
*size += parg->type->size * (parg->count ?: 1); |
|
|
|
ret = -ENOMEM; |
|
if (parg->count) { |
|
len = strlen(parg->type->fmttype) + 6; |
|
parg->fmt = kmalloc(len, GFP_KERNEL); |
|
if (!parg->fmt) |
|
goto out; |
|
snprintf(parg->fmt, len, "%s[%d]", parg->type->fmttype, |
|
parg->count); |
|
} |
|
|
|
code = tmp = kcalloc(FETCH_INSN_MAX, sizeof(*code), GFP_KERNEL); |
|
if (!code) |
|
goto out; |
|
code[FETCH_INSN_MAX - 1].op = FETCH_OP_END; |
|
|
|
ret = parse_probe_arg(arg, parg->type, &code, &code[FETCH_INSN_MAX - 1], |
|
flags, offset); |
|
if (ret) |
|
goto fail; |
|
|
|
ret = -EINVAL; |
|
/* Store operation */ |
|
if (!strcmp(parg->type->name, "string") || |
|
!strcmp(parg->type->name, "ustring")) { |
|
if (code->op != FETCH_OP_DEREF && code->op != FETCH_OP_UDEREF && |
|
code->op != FETCH_OP_IMM && code->op != FETCH_OP_COMM && |
|
code->op != FETCH_OP_DATA && code->op != FETCH_OP_TP_ARG) { |
|
trace_probe_log_err(offset + (t ? (t - arg) : 0), |
|
BAD_STRING); |
|
goto fail; |
|
} |
|
if ((code->op == FETCH_OP_IMM || code->op == FETCH_OP_COMM || |
|
code->op == FETCH_OP_DATA) || code->op == FETCH_OP_TP_ARG || |
|
parg->count) { |
|
/* |
|
* IMM, DATA and COMM is pointing actual address, those |
|
* must be kept, and if parg->count != 0, this is an |
|
* array of string pointers instead of string address |
|
* itself. |
|
*/ |
|
code++; |
|
if (code->op != FETCH_OP_NOP) { |
|
trace_probe_log_err(offset, TOO_MANY_OPS); |
|
goto fail; |
|
} |
|
} |
|
/* If op == DEREF, replace it with STRING */ |
|
if (!strcmp(parg->type->name, "ustring") || |
|
code->op == FETCH_OP_UDEREF) |
|
code->op = FETCH_OP_ST_USTRING; |
|
else |
|
code->op = FETCH_OP_ST_STRING; |
|
code->size = parg->type->size; |
|
parg->dynamic = true; |
|
} else if (code->op == FETCH_OP_DEREF) { |
|
code->op = FETCH_OP_ST_MEM; |
|
code->size = parg->type->size; |
|
} else if (code->op == FETCH_OP_UDEREF) { |
|
code->op = FETCH_OP_ST_UMEM; |
|
code->size = parg->type->size; |
|
} else { |
|
code++; |
|
if (code->op != FETCH_OP_NOP) { |
|
trace_probe_log_err(offset, TOO_MANY_OPS); |
|
goto fail; |
|
} |
|
code->op = FETCH_OP_ST_RAW; |
|
code->size = parg->type->size; |
|
} |
|
scode = code; |
|
/* Modify operation */ |
|
if (t != NULL) { |
|
ret = __parse_bitfield_probe_arg(t, parg->type, &code); |
|
if (ret) { |
|
trace_probe_log_err(offset + t - arg, BAD_BITFIELD); |
|
goto fail; |
|
} |
|
} |
|
ret = -EINVAL; |
|
/* Loop(Array) operation */ |
|
if (parg->count) { |
|
if (scode->op != FETCH_OP_ST_MEM && |
|
scode->op != FETCH_OP_ST_STRING && |
|
scode->op != FETCH_OP_ST_USTRING) { |
|
trace_probe_log_err(offset + (t ? (t - arg) : 0), |
|
BAD_STRING); |
|
goto fail; |
|
} |
|
code++; |
|
if (code->op != FETCH_OP_NOP) { |
|
trace_probe_log_err(offset, TOO_MANY_OPS); |
|
goto fail; |
|
} |
|
code->op = FETCH_OP_LP_ARRAY; |
|
code->param = parg->count; |
|
} |
|
code++; |
|
code->op = FETCH_OP_END; |
|
|
|
ret = 0; |
|
/* Shrink down the code buffer */ |
|
parg->code = kcalloc(code - tmp + 1, sizeof(*code), GFP_KERNEL); |
|
if (!parg->code) |
|
ret = -ENOMEM; |
|
else |
|
memcpy(parg->code, tmp, sizeof(*code) * (code - tmp + 1)); |
|
|
|
fail: |
|
if (ret) { |
|
for (code = tmp; code < tmp + FETCH_INSN_MAX; code++) |
|
if (code->op == FETCH_NOP_SYMBOL || |
|
code->op == FETCH_OP_DATA) |
|
kfree(code->data); |
|
} |
|
kfree(tmp); |
|
out: |
|
kfree(arg); |
|
|
|
return ret; |
|
} |
|
|
|
/* Return 1 if name is reserved or already used by another argument */ |
|
static int traceprobe_conflict_field_name(const char *name, |
|
struct probe_arg *args, int narg) |
|
{ |
|
int i; |
|
|
|
for (i = 0; i < ARRAY_SIZE(reserved_field_names); i++) |
|
if (strcmp(reserved_field_names[i], name) == 0) |
|
return 1; |
|
|
|
for (i = 0; i < narg; i++) |
|
if (strcmp(args[i].name, name) == 0) |
|
return 1; |
|
|
|
return 0; |
|
} |
|
|
|
int traceprobe_parse_probe_arg(struct trace_probe *tp, int i, const char *arg, |
|
unsigned int flags) |
|
{ |
|
struct probe_arg *parg = &tp->args[i]; |
|
const char *body; |
|
|
|
/* Increment count for freeing args in error case */ |
|
tp->nr_args++; |
|
|
|
body = strchr(arg, '='); |
|
if (body) { |
|
if (body - arg > MAX_ARG_NAME_LEN) { |
|
trace_probe_log_err(0, ARG_NAME_TOO_LONG); |
|
return -EINVAL; |
|
} else if (body == arg) { |
|
trace_probe_log_err(0, NO_ARG_NAME); |
|
return -EINVAL; |
|
} |
|
parg->name = kmemdup_nul(arg, body - arg, GFP_KERNEL); |
|
body++; |
|
} else { |
|
/* If argument name is omitted, set "argN" */ |
|
parg->name = kasprintf(GFP_KERNEL, "arg%d", i + 1); |
|
body = arg; |
|
} |
|
if (!parg->name) |
|
return -ENOMEM; |
|
|
|
if (!is_good_name(parg->name)) { |
|
trace_probe_log_err(0, BAD_ARG_NAME); |
|
return -EINVAL; |
|
} |
|
if (traceprobe_conflict_field_name(parg->name, tp->args, i)) { |
|
trace_probe_log_err(0, USED_ARG_NAME); |
|
return -EINVAL; |
|
} |
|
/* Parse fetch argument */ |
|
return traceprobe_parse_probe_arg_body(body, &tp->size, parg, flags, |
|
body - arg); |
|
} |
|
|
|
void traceprobe_free_probe_arg(struct probe_arg *arg) |
|
{ |
|
struct fetch_insn *code = arg->code; |
|
|
|
while (code && code->op != FETCH_OP_END) { |
|
if (code->op == FETCH_NOP_SYMBOL || |
|
code->op == FETCH_OP_DATA) |
|
kfree(code->data); |
|
code++; |
|
} |
|
kfree(arg->code); |
|
kfree(arg->name); |
|
kfree(arg->comm); |
|
kfree(arg->fmt); |
|
} |
|
|
|
int traceprobe_update_arg(struct probe_arg *arg) |
|
{ |
|
struct fetch_insn *code = arg->code; |
|
long offset; |
|
char *tmp; |
|
char c; |
|
int ret = 0; |
|
|
|
while (code && code->op != FETCH_OP_END) { |
|
if (code->op == FETCH_NOP_SYMBOL) { |
|
if (code[1].op != FETCH_OP_IMM) |
|
return -EINVAL; |
|
|
|
tmp = strpbrk(code->data, "+-"); |
|
if (tmp) |
|
c = *tmp; |
|
ret = traceprobe_split_symbol_offset(code->data, |
|
&offset); |
|
if (ret) |
|
return ret; |
|
|
|
code[1].immediate = |
|
(unsigned long)kallsyms_lookup_name(code->data); |
|
if (tmp) |
|
*tmp = c; |
|
if (!code[1].immediate) |
|
return -ENOENT; |
|
code[1].immediate += offset; |
|
} |
|
code++; |
|
} |
|
return 0; |
|
} |
|
|
|
/* When len=0, we just calculate the needed length */ |
|
#define LEN_OR_ZERO (len ? len - pos : 0) |
|
static int __set_print_fmt(struct trace_probe *tp, char *buf, int len, |
|
enum probe_print_type ptype) |
|
{ |
|
struct probe_arg *parg; |
|
int i, j; |
|
int pos = 0; |
|
const char *fmt, *arg; |
|
|
|
switch (ptype) { |
|
case PROBE_PRINT_NORMAL: |
|
fmt = "(%lx)"; |
|
arg = "REC->" FIELD_STRING_IP; |
|
break; |
|
case PROBE_PRINT_RETURN: |
|
fmt = "(%lx <- %lx)"; |
|
arg = "REC->" FIELD_STRING_FUNC ", REC->" FIELD_STRING_RETIP; |
|
break; |
|
case PROBE_PRINT_EVENT: |
|
fmt = "(%u)"; |
|
arg = "REC->" FIELD_STRING_TYPE; |
|
break; |
|
default: |
|
WARN_ON_ONCE(1); |
|
return 0; |
|
} |
|
|
|
pos += snprintf(buf + pos, LEN_OR_ZERO, "\"%s", fmt); |
|
|
|
for (i = 0; i < tp->nr_args; i++) { |
|
parg = tp->args + i; |
|
pos += snprintf(buf + pos, LEN_OR_ZERO, " %s=", parg->name); |
|
if (parg->count) { |
|
pos += snprintf(buf + pos, LEN_OR_ZERO, "{%s", |
|
parg->type->fmt); |
|
for (j = 1; j < parg->count; j++) |
|
pos += snprintf(buf + pos, LEN_OR_ZERO, ",%s", |
|
parg->type->fmt); |
|
pos += snprintf(buf + pos, LEN_OR_ZERO, "}"); |
|
} else |
|
pos += snprintf(buf + pos, LEN_OR_ZERO, "%s", |
|
parg->type->fmt); |
|
} |
|
|
|
pos += snprintf(buf + pos, LEN_OR_ZERO, "\", %s", arg); |
|
|
|
for (i = 0; i < tp->nr_args; i++) { |
|
parg = tp->args + i; |
|
if (parg->count) { |
|
if ((strcmp(parg->type->name, "string") == 0) || |
|
(strcmp(parg->type->name, "ustring") == 0)) |
|
fmt = ", __get_str(%s[%d])"; |
|
else |
|
fmt = ", REC->%s[%d]"; |
|
for (j = 0; j < parg->count; j++) |
|
pos += snprintf(buf + pos, LEN_OR_ZERO, |
|
fmt, parg->name, j); |
|
} else { |
|
if ((strcmp(parg->type->name, "string") == 0) || |
|
(strcmp(parg->type->name, "ustring") == 0)) |
|
fmt = ", __get_str(%s)"; |
|
else |
|
fmt = ", REC->%s"; |
|
pos += snprintf(buf + pos, LEN_OR_ZERO, |
|
fmt, parg->name); |
|
} |
|
} |
|
|
|
/* return the length of print_fmt */ |
|
return pos; |
|
} |
|
#undef LEN_OR_ZERO |
|
|
|
int traceprobe_set_print_fmt(struct trace_probe *tp, enum probe_print_type ptype) |
|
{ |
|
struct trace_event_call *call = trace_probe_event_call(tp); |
|
int len; |
|
char *print_fmt; |
|
|
|
/* First: called with 0 length to calculate the needed length */ |
|
len = __set_print_fmt(tp, NULL, 0, ptype); |
|
print_fmt = kmalloc(len + 1, GFP_KERNEL); |
|
if (!print_fmt) |
|
return -ENOMEM; |
|
|
|
/* Second: actually write the @print_fmt */ |
|
__set_print_fmt(tp, print_fmt, len + 1, ptype); |
|
call->print_fmt = print_fmt; |
|
|
|
return 0; |
|
} |
|
|
|
int traceprobe_define_arg_fields(struct trace_event_call *event_call, |
|
size_t offset, struct trace_probe *tp) |
|
{ |
|
int ret, i; |
|
|
|
/* Set argument names as fields */ |
|
for (i = 0; i < tp->nr_args; i++) { |
|
struct probe_arg *parg = &tp->args[i]; |
|
const char *fmt = parg->type->fmttype; |
|
int size = parg->type->size; |
|
|
|
if (parg->fmt) |
|
fmt = parg->fmt; |
|
if (parg->count) |
|
size *= parg->count; |
|
ret = trace_define_field(event_call, fmt, parg->name, |
|
offset + parg->offset, size, |
|
parg->type->is_signed, |
|
FILTER_OTHER); |
|
if (ret) |
|
return ret; |
|
} |
|
return 0; |
|
} |
|
|
|
static void trace_probe_event_free(struct trace_probe_event *tpe) |
|
{ |
|
kfree(tpe->class.system); |
|
kfree(tpe->call.name); |
|
kfree(tpe->call.print_fmt); |
|
kfree(tpe); |
|
} |
|
|
|
int trace_probe_append(struct trace_probe *tp, struct trace_probe *to) |
|
{ |
|
if (trace_probe_has_sibling(tp)) |
|
return -EBUSY; |
|
|
|
list_del_init(&tp->list); |
|
trace_probe_event_free(tp->event); |
|
|
|
tp->event = to->event; |
|
list_add_tail(&tp->list, trace_probe_probe_list(to)); |
|
|
|
return 0; |
|
} |
|
|
|
void trace_probe_unlink(struct trace_probe *tp) |
|
{ |
|
list_del_init(&tp->list); |
|
if (list_empty(trace_probe_probe_list(tp))) |
|
trace_probe_event_free(tp->event); |
|
tp->event = NULL; |
|
} |
|
|
|
void trace_probe_cleanup(struct trace_probe *tp) |
|
{ |
|
int i; |
|
|
|
for (i = 0; i < tp->nr_args; i++) |
|
traceprobe_free_probe_arg(&tp->args[i]); |
|
|
|
if (tp->event) |
|
trace_probe_unlink(tp); |
|
} |
|
|
|
int trace_probe_init(struct trace_probe *tp, const char *event, |
|
const char *group, bool alloc_filter) |
|
{ |
|
struct trace_event_call *call; |
|
size_t size = sizeof(struct trace_probe_event); |
|
int ret = 0; |
|
|
|
if (!event || !group) |
|
return -EINVAL; |
|
|
|
if (alloc_filter) |
|
size += sizeof(struct trace_uprobe_filter); |
|
|
|
tp->event = kzalloc(size, GFP_KERNEL); |
|
if (!tp->event) |
|
return -ENOMEM; |
|
|
|
INIT_LIST_HEAD(&tp->event->files); |
|
INIT_LIST_HEAD(&tp->event->class.fields); |
|
INIT_LIST_HEAD(&tp->event->probes); |
|
INIT_LIST_HEAD(&tp->list); |
|
list_add(&tp->list, &tp->event->probes); |
|
|
|
call = trace_probe_event_call(tp); |
|
call->class = &tp->event->class; |
|
call->name = kstrdup(event, GFP_KERNEL); |
|
if (!call->name) { |
|
ret = -ENOMEM; |
|
goto error; |
|
} |
|
|
|
tp->event->class.system = kstrdup(group, GFP_KERNEL); |
|
if (!tp->event->class.system) { |
|
ret = -ENOMEM; |
|
goto error; |
|
} |
|
|
|
return 0; |
|
|
|
error: |
|
trace_probe_cleanup(tp); |
|
return ret; |
|
} |
|
|
|
static struct trace_event_call * |
|
find_trace_event_call(const char *system, const char *event_name) |
|
{ |
|
struct trace_event_call *tp_event; |
|
const char *name; |
|
|
|
list_for_each_entry(tp_event, &ftrace_events, list) { |
|
if (!tp_event->class->system || |
|
strcmp(system, tp_event->class->system)) |
|
continue; |
|
name = trace_event_name(tp_event); |
|
if (!name || strcmp(event_name, name)) |
|
continue; |
|
return tp_event; |
|
} |
|
|
|
return NULL; |
|
} |
|
|
|
int trace_probe_register_event_call(struct trace_probe *tp) |
|
{ |
|
struct trace_event_call *call = trace_probe_event_call(tp); |
|
int ret; |
|
|
|
lockdep_assert_held(&event_mutex); |
|
|
|
if (find_trace_event_call(trace_probe_group_name(tp), |
|
trace_probe_name(tp))) |
|
return -EEXIST; |
|
|
|
ret = register_trace_event(&call->event); |
|
if (!ret) |
|
return -ENODEV; |
|
|
|
ret = trace_add_event_call(call); |
|
if (ret) |
|
unregister_trace_event(&call->event); |
|
|
|
return ret; |
|
} |
|
|
|
int trace_probe_add_file(struct trace_probe *tp, struct trace_event_file *file) |
|
{ |
|
struct event_file_link *link; |
|
|
|
link = kmalloc(sizeof(*link), GFP_KERNEL); |
|
if (!link) |
|
return -ENOMEM; |
|
|
|
link->file = file; |
|
INIT_LIST_HEAD(&link->list); |
|
list_add_tail_rcu(&link->list, &tp->event->files); |
|
trace_probe_set_flag(tp, TP_FLAG_TRACE); |
|
return 0; |
|
} |
|
|
|
struct event_file_link *trace_probe_get_file_link(struct trace_probe *tp, |
|
struct trace_event_file *file) |
|
{ |
|
struct event_file_link *link; |
|
|
|
trace_probe_for_each_link(link, tp) { |
|
if (link->file == file) |
|
return link; |
|
} |
|
|
|
return NULL; |
|
} |
|
|
|
int trace_probe_remove_file(struct trace_probe *tp, |
|
struct trace_event_file *file) |
|
{ |
|
struct event_file_link *link; |
|
|
|
link = trace_probe_get_file_link(tp, file); |
|
if (!link) |
|
return -ENOENT; |
|
|
|
list_del_rcu(&link->list); |
|
synchronize_rcu(); |
|
kfree(link); |
|
|
|
if (list_empty(&tp->event->files)) |
|
trace_probe_clear_flag(tp, TP_FLAG_TRACE); |
|
|
|
return 0; |
|
} |
|
|
|
/* |
|
* Return the smallest index of different type argument (start from 1). |
|
* If all argument types and name are same, return 0. |
|
*/ |
|
int trace_probe_compare_arg_type(struct trace_probe *a, struct trace_probe *b) |
|
{ |
|
int i; |
|
|
|
/* In case of more arguments */ |
|
if (a->nr_args < b->nr_args) |
|
return a->nr_args + 1; |
|
if (a->nr_args > b->nr_args) |
|
return b->nr_args + 1; |
|
|
|
for (i = 0; i < a->nr_args; i++) { |
|
if ((b->nr_args <= i) || |
|
((a->args[i].type != b->args[i].type) || |
|
(a->args[i].count != b->args[i].count) || |
|
strcmp(a->args[i].name, b->args[i].name))) |
|
return i + 1; |
|
} |
|
|
|
return 0; |
|
} |
|
|
|
bool trace_probe_match_command_args(struct trace_probe *tp, |
|
int argc, const char **argv) |
|
{ |
|
char buf[MAX_ARGSTR_LEN + 1]; |
|
int i; |
|
|
|
if (tp->nr_args < argc) |
|
return false; |
|
|
|
for (i = 0; i < argc; i++) { |
|
snprintf(buf, sizeof(buf), "%s=%s", |
|
tp->args[i].name, tp->args[i].comm); |
|
if (strcmp(buf, argv[i])) |
|
return false; |
|
} |
|
return true; |
|
} |
|
|
|
int trace_probe_create(const char *raw_command, int (*createfn)(int, const char **)) |
|
{ |
|
int argc = 0, ret = 0; |
|
char **argv; |
|
|
|
argv = argv_split(GFP_KERNEL, raw_command, &argc); |
|
if (!argv) |
|
return -ENOMEM; |
|
|
|
if (argc) |
|
ret = createfn(argc, (const char **)argv); |
|
|
|
argv_free(argv); |
|
|
|
return ret; |
|
}
|
|
|