Ejemplo n.º 1
0
static void
fbt_provide_module_user_syms(struct modctl *ctl)
{
	unsigned int i;
	char *modname = ctl->mod_modname;

	dtrace_module_symbols_t* module_symbols = ctl->mod_user_symbols;
	if (module_symbols) {
		for (i=0; i<module_symbols->dtmodsyms_count; i++) {

		        /*
			 * symbol->dtsym_addr (the symbol address) passed in from
			 * user space, is already slid for both kexts and kernel.
			 */
			dtrace_symbol_t* symbol = &module_symbols->dtmodsyms_symbols[i];

			char* name = symbol->dtsym_name;

			/* Lop off omnipresent leading underscore. */
			if (*name == '_')
				name += 1;

			/*
			 * We're only blacklisting functions in the kernel for now.
			 */
                        if (MOD_IS_MACH_KERNEL(ctl) && fbt_excluded(name))
			        continue;

			/*
			 * Ignore symbols with a null address
			 */
			if (!symbol->dtsym_addr)
				continue;

			fbt_provide_probe(ctl, (uintptr_t)symbol->dtsym_addr, (uintptr_t)(symbol->dtsym_addr + symbol->dtsym_size), modname, name, (machine_inst_t*)(uintptr_t)symbol->dtsym_addr);
		}
	}
}
Ejemplo n.º 2
0
int
fbt_provide_module_function(linker_file_t lf, int symindx,
    linker_symval_t *symval, void *opaque)
{
	fbt_probe_t *fbt, *retfbt;
	uint32_t *instr, *limit;
	const char *name;
	char *modname;

	modname = opaque;
	name = symval->name;

	/* Check if function is excluded from instrumentation */
	if (fbt_excluded(name))
		return (0);

	instr = (uint32_t *)(symval->value);
	limit = (uint32_t *)(symval->value + symval->size);

	/* Look for store double to ra register */
	for (; instr < limit; instr++) {
		if ((*instr & LDSD_RA_SP_MASK) == SD_RA_SP)
			break;
	}

	if (instr >= limit)
		return (0);

	fbt = malloc(sizeof (fbt_probe_t), M_FBT, M_WAITOK | M_ZERO);
	fbt->fbtp_name = name;
	fbt->fbtp_id = dtrace_probe_create(fbt_id, modname,
	    name, FBT_ENTRY, 3, fbt);
	fbt->fbtp_patchpoint = instr;
	fbt->fbtp_ctl = lf;
	fbt->fbtp_loadcnt = lf->loadcnt;
	fbt->fbtp_savedval = *instr;
	fbt->fbtp_patchval = FBT_PATCHVAL;
	fbt->fbtp_rval = DTRACE_INVOP_SD;
	fbt->fbtp_symindx = symindx;

	fbt->fbtp_hashnext = fbt_probetab[FBT_ADDR2NDX(instr)];
	fbt_probetab[FBT_ADDR2NDX(instr)] = fbt;

	lf->fbt_nentries++;

	retfbt = NULL;
again:
	for (; instr < limit; instr++) {
		if ((*instr & LDSD_RA_SP_MASK) == LD_RA_SP) {
			break;
		}
	}

	if (instr >= limit)
		return (0);

	/*
	 * We have a winner!
	 */
	fbt = malloc(sizeof (fbt_probe_t), M_FBT, M_WAITOK | M_ZERO);
	fbt->fbtp_name = name;
	if (retfbt == NULL) {
		fbt->fbtp_id = dtrace_probe_create(fbt_id, modname,
		    name, FBT_RETURN, 3, fbt);
	} else {
		retfbt->fbtp_next = fbt;
		fbt->fbtp_id = retfbt->fbtp_id;
	}
	retfbt = fbt;

	fbt->fbtp_patchpoint = instr;
	fbt->fbtp_ctl = lf;
	fbt->fbtp_loadcnt = lf->loadcnt;
	fbt->fbtp_symindx = symindx;
	fbt->fbtp_rval = DTRACE_INVOP_LD;
	fbt->fbtp_savedval = *instr;
	fbt->fbtp_patchval = FBT_PATCHVAL;
	fbt->fbtp_hashnext = fbt_probetab[FBT_ADDR2NDX(instr)];
	fbt_probetab[FBT_ADDR2NDX(instr)] = fbt;

	lf->fbt_nentries++;

	instr++;
	goto again;
}
Ejemplo n.º 3
0
int
fbt_provide_module_function(linker_file_t lf, int symindx,
    linker_symval_t *symval, void *opaque)
{
	fbt_probe_t *fbt, *retfbt;
	uint32_t *instr, *limit;
	const char *name;
	char *modname;
	int patchval;
	int rval;

	modname = opaque;
	name = symval->name;

	/* Check if function is excluded from instrumentation */
	if (fbt_excluded(name))
		return (0);

	instr = (uint32_t *)(symval->value);
	limit = (uint32_t *)(symval->value + symval->size);

	/* Look for sd operation */
	for (; instr < limit; instr++) {
		/* Look for a non-compressed store of ra to sp */
		if (match_opcode(*instr, (MATCH_SD | RS2_RA | RS1_SP),
		    (MASK_SD | RS2_MASK | RS1_MASK))) {
			rval = DTRACE_INVOP_SD;
			patchval = FBT_PATCHVAL;
			break;
		}

		/* Look for a 'C'-compressed store of ra to sp. */
		if (check_c_sdsp(&instr)) {
			rval = DTRACE_INVOP_C_SDSP;
			patchval = FBT_C_PATCHVAL;
			break;
		}
	}

	if (instr >= limit)
		return (0);

	fbt = malloc(sizeof (fbt_probe_t), M_FBT, M_WAITOK | M_ZERO);
	fbt->fbtp_name = name;
	fbt->fbtp_id = dtrace_probe_create(fbt_id, modname,
	    name, FBT_ENTRY, 3, fbt);
	fbt->fbtp_patchpoint = instr;
	fbt->fbtp_ctl = lf;
	fbt->fbtp_loadcnt = lf->loadcnt;
	fbt->fbtp_savedval = *instr;
	fbt->fbtp_patchval = patchval;
	fbt->fbtp_rval = rval;
	fbt->fbtp_symindx = symindx;

	fbt->fbtp_hashnext = fbt_probetab[FBT_ADDR2NDX(instr)];
	fbt_probetab[FBT_ADDR2NDX(instr)] = fbt;

	lf->fbt_nentries++;

	retfbt = NULL;
again:
	for (; instr < limit; instr++) {
		/* Look for non-compressed return */
		if (match_opcode(*instr, (MATCH_JALR | (X_RA << RS1_SHIFT)),
		    (MASK_JALR | RD_MASK | RS1_MASK | IMM_MASK))) {
			rval = DTRACE_INVOP_RET;
			patchval = FBT_PATCHVAL;
			break;
		}

		/* Look for 'C'-compressed return */
		if (check_c_ret(&instr)) {
			rval = DTRACE_INVOP_C_RET;
			patchval = FBT_C_PATCHVAL;
			break;
		}
	}

	if (instr >= limit)
		return (0);

	/*
	 * We have a winner!
	 */
	fbt = malloc(sizeof (fbt_probe_t), M_FBT, M_WAITOK | M_ZERO);
	fbt->fbtp_name = name;
	if (retfbt == NULL) {
		fbt->fbtp_id = dtrace_probe_create(fbt_id, modname,
		    name, FBT_RETURN, 3, fbt);
	} else {
		retfbt->fbtp_probenext = fbt;
		fbt->fbtp_id = retfbt->fbtp_id;
	}
	retfbt = fbt;

	fbt->fbtp_patchpoint = instr;
	fbt->fbtp_ctl = lf;
	fbt->fbtp_loadcnt = lf->loadcnt;
	fbt->fbtp_symindx = symindx;
	fbt->fbtp_rval = rval;
	fbt->fbtp_savedval = *instr;
	fbt->fbtp_patchval = patchval;
	fbt->fbtp_hashnext = fbt_probetab[FBT_ADDR2NDX(instr)];
	fbt_probetab[FBT_ADDR2NDX(instr)] = fbt;

	lf->fbt_nentries++;

	instr++;
	goto again;
}