Commit 450e7dd4 authored by Christophe Leroy's avatar Christophe Leroy Committed by Michael Ellerman
Browse files

powerpc/prom_init: don't use string functions from lib/ 



When KASAN is active, the string functions in lib/ are doing the
KASAN checks. This is too early for prom_init.

This patch implements dedicated string functions for prom_init,
which will be compiled in with KASAN disabled.

Size of prom_init before the patch:
   text	   data	    bss	    dec	    hex	filename
  12060	    488	   6960	  19508	   4c34	arch/powerpc/kernel/prom_init.o

Size of prom_init after the patch:
   text	   data	    bss	    dec	    hex	filename
  12460	    488	   6960	  19908	   4dc4	arch/powerpc/kernel/prom_init.o

This increases the size of prom_init a bit, but as prom_init is
in __init section, it is freed after boot anyway.

Signed-off-by: default avatarChristophe Leroy <christophe.leroy@c-s.fr>
Signed-off-by: default avatarMichael Ellerman <mpe@ellerman.id.au>
parent cbe46bd4

arch/powerpc/kernel/prom_init.c

+170 −41
Original line number Diff line number Diff line
@@ -224,6 +224,135 @@ static bool __prombss rtas_has_query_cpu_stopped; 
#define PHANDLE_VALID(p)	((p) != 0 && (p) != PROM_ERROR)

#define IHANDLE_VALID(i)	((i) != 0 && (i) != PROM_ERROR)



/* Copied from lib/string.c and lib/kstrtox.c */



static int __init prom_strcmp(const char *cs, const char *ct)

{

	unsigned char c1, c2;



	while (1) {

		c1 = *cs++;

		c2 = *ct++;

		if (c1 != c2)

			return c1 < c2 ? -1 : 1;

		if (!c1)

			break;

	}

	return 0;

}



static char __init *prom_strcpy(char *dest, const char *src)

{

	char *tmp = dest;



	while ((*dest++ = *src++) != '\0')

		/* nothing */;

	return tmp;

}



static int __init prom_strncmp(const char *cs, const char *ct, size_t count)

{

	unsigned char c1, c2;



	while (count) {

		c1 = *cs++;

		c2 = *ct++;

		if (c1 != c2)

			return c1 < c2 ? -1 : 1;

		if (!c1)

			break;

		count--;

	}

	return 0;

}



static size_t __init prom_strlen(const char *s)

{

	const char *sc;



	for (sc = s; *sc != '\0'; ++sc)

		/* nothing */;

	return sc - s;

}



static int __init prom_memcmp(const void *cs, const void *ct, size_t count)

{

	const unsigned char *su1, *su2;

	int res = 0;



	for (su1 = cs, su2 = ct; 0 < count; ++su1, ++su2, count--)

		if ((res = *su1 - *su2) != 0)

			break;

	return res;

}



static char __init *prom_strstr(const char *s1, const char *s2)

{

	size_t l1, l2;



	l2 = prom_strlen(s2);

	if (!l2)

		return (char *)s1;

	l1 = prom_strlen(s1);

	while (l1 >= l2) {

		l1--;

		if (!prom_memcmp(s1, s2, l2))

			return (char *)s1;

		s1++;

	}

	return NULL;

}



static size_t __init prom_strlcpy(char *dest, const char *src, size_t size)

{

	size_t ret = prom_strlen(src);



	if (size) {

		size_t len = (ret >= size) ? size - 1 : ret;

		memcpy(dest, src, len);

		dest[len] = '\0';

	}

	return ret;

}



#ifdef CONFIG_PPC_PSERIES

static int __init prom_strtobool(const char *s, bool *res)

{

	if (!s)

		return -EINVAL;



	switch (s[0]) {

	case 'y':

	case 'Y':

	case '1':

		*res = true;

		return 0;

	case 'n':

	case 'N':

	case '0':

		*res = false;

		return 0;

	case 'o':

	case 'O':

		switch (s[1]) {

		case 'n':

		case 'N':

			*res = true;

			return 0;

		case 'f':

		case 'F':

			*res = false;

			return 0;

		default:

			break;

		}

	default:

		break;

	}



	return -EINVAL;

}

#endif



/* This is the one and *ONLY* place where we actually call open

 * firmware.
@@ -555,7 +684,7 @@ static int __init prom_setprop(phandle node, const char *nodename, 
	add_string(&p, tohex((u32)(unsigned long) value));

	add_string(&p, tohex(valuelen));

	add_string(&p, tohex(ADDR(pname)));

	add_string(&p, tohex(strlen(pname)));

	add_string(&p, tohex(prom_strlen(pname)));

	add_string(&p, "property");

	*p = 0;

	return call_prom("interpret", 1, 1, (u32)(unsigned long) cmd);
@@ -638,23 +767,23 @@ static void __init early_cmdline_parse(void) 
	if ((long)prom.chosen > 0)

		l = prom_getprop(prom.chosen, "bootargs", p, COMMAND_LINE_SIZE-1);

	if (IS_ENABLED(CONFIG_CMDLINE_BOOL) && (l <= 0 || p[0] == '\0')) /* dbl check */

		strlcpy(prom_cmd_line, CONFIG_CMDLINE, sizeof(prom_cmd_line));

		prom_strlcpy(prom_cmd_line, CONFIG_CMDLINE, sizeof(prom_cmd_line));

	prom_printf("command line: %s\n", prom_cmd_line);



#ifdef CONFIG_PPC64

	opt = strstr(prom_cmd_line, "iommu=");

	opt = prom_strstr(prom_cmd_line, "iommu=");

	if (opt) {

		prom_printf("iommu opt is: %s\n", opt);

		opt += 6;

		while (*opt && *opt == ' ')

			opt++;

		if (!strncmp(opt, "off", 3))

		if (!prom_strncmp(opt, "off", 3))

			prom_iommu_off = 1;

		else if (!strncmp(opt, "force", 5))

		else if (!prom_strncmp(opt, "force", 5))

			prom_iommu_force_on = 1;

	}

#endif

	opt = strstr(prom_cmd_line, "mem=");

	opt = prom_strstr(prom_cmd_line, "mem=");

	if (opt) {

		opt += 4;

		prom_memory_limit = prom_memparse(opt, (const char **)&opt);
@@ -666,13 +795,13 @@ static void __init early_cmdline_parse(void) 


#ifdef CONFIG_PPC_PSERIES

	prom_radix_disable = !IS_ENABLED(CONFIG_PPC_RADIX_MMU_DEFAULT);

	opt = strstr(prom_cmd_line, "disable_radix");

	opt = prom_strstr(prom_cmd_line, "disable_radix");

	if (opt) {

		opt += 13;

		if (*opt && *opt == '=') {

			bool val;



			if (kstrtobool(++opt, &val))

			if (prom_strtobool(++opt, &val))

				prom_radix_disable = false;

			else

				prom_radix_disable = val;
@@ -1025,7 +1154,7 @@ static int __init prom_count_smt_threads(void) 
		type[0] = 0;

		prom_getprop(node, "device_type", type, sizeof(type));



		if (strcmp(type, "cpu"))

		if (prom_strcmp(type, "cpu"))

			continue;

		/*

		 * There is an entry for each smt thread, each entry being
@@ -1472,7 +1601,7 @@ static void __init prom_init_mem(void) 
			 */

			prom_getprop(node, "name", type, sizeof(type));

		}

		if (strcmp(type, "memory"))

		if (prom_strcmp(type, "memory"))

			continue;



		plen = prom_getprop(node, "reg", regbuf, sizeof(regbuf));
@@ -1753,19 +1882,19 @@ static void __init prom_initialize_tce_table(void) 
		prom_getprop(node, "device_type", type, sizeof(type));

		prom_getprop(node, "model", model, sizeof(model));



		if ((type[0] == 0) || (strstr(type, "pci") == NULL))

		if ((type[0] == 0) || (prom_strstr(type, "pci") == NULL))

			continue;



		/* Keep the old logic intact to avoid regression. */

		if (compatible[0] != 0) {

			if ((strstr(compatible, "python") == NULL) &&

			    (strstr(compatible, "Speedwagon") == NULL) &&

			    (strstr(compatible, "Winnipeg") == NULL))

			if ((prom_strstr(compatible, "python") == NULL) &&

			    (prom_strstr(compatible, "Speedwagon") == NULL) &&

			    (prom_strstr(compatible, "Winnipeg") == NULL))

				continue;

		} else if (model[0] != 0) {

			if ((strstr(model, "ython") == NULL) &&

			    (strstr(model, "peedwagon") == NULL) &&

			    (strstr(model, "innipeg") == NULL))

			if ((prom_strstr(model, "ython") == NULL) &&

			    (prom_strstr(model, "peedwagon") == NULL) &&

			    (prom_strstr(model, "innipeg") == NULL))

				continue;

		}
@@ -1914,12 +2043,12 @@ static void __init prom_hold_cpus(void) 


		type[0] = 0;

		prom_getprop(node, "device_type", type, sizeof(type));

		if (strcmp(type, "cpu") != 0)

		if (prom_strcmp(type, "cpu") != 0)

			continue;



		/* Skip non-configured cpus. */

		if (prom_getprop(node, "status", type, sizeof(type)) > 0)

			if (strcmp(type, "okay") != 0)

			if (prom_strcmp(type, "okay") != 0)

				continue;



		reg = cpu_to_be32(-1); /* make sparse happy */
@@ -1995,9 +2124,9 @@ static void __init prom_find_mmu(void) 
		return;

	version[sizeof(version) - 1] = 0;

	/* XXX might need to add other versions here */

	if (strcmp(version, "Open Firmware, 1.0.5") == 0)

	if (prom_strcmp(version, "Open Firmware, 1.0.5") == 0)

		of_workarounds = OF_WA_CLAIM;

	else if (strncmp(version, "FirmWorks,3.", 12) == 0) {

	else if (prom_strncmp(version, "FirmWorks,3.", 12) == 0) {

		of_workarounds = OF_WA_CLAIM | OF_WA_LONGTRAIL;

		call_prom("interpret", 1, 1, "dev /memory 0 to allow-reclaim");

	} else
@@ -2030,7 +2159,7 @@ static void __init prom_init_stdout(void) 
	call_prom("instance-to-path", 3, 1, prom.stdout, path, 255);

	prom_printf("OF stdout device is: %s\n", of_stdout_device);

	prom_setprop(prom.chosen, "/chosen", "linux,stdout-path",

		     path, strlen(path) + 1);

		     path, prom_strlen(path) + 1);



	/* instance-to-package fails on PA-Semi */

	stdout_node = call_prom("instance-to-package", 1, 1, prom.stdout);
@@ -2040,7 +2169,7 @@ static void __init prom_init_stdout(void) 
		/* If it's a display, note it */

		memset(type, 0, sizeof(type));

		prom_getprop(stdout_node, "device_type", type, sizeof(type));

		if (strcmp(type, "display") == 0)

		if (prom_strcmp(type, "display") == 0)

			prom_setprop(stdout_node, path, "linux,boot-display", NULL, 0);

	}

}
@@ -2061,19 +2190,19 @@ static int __init prom_find_machine_type(void) 
		compat[len] = 0;

		while (i < len) {

			char *p = &compat[i];

			int sl = strlen(p);

			int sl = prom_strlen(p);

			if (sl == 0)

				break;

			if (strstr(p, "Power Macintosh") ||

			    strstr(p, "MacRISC"))

			if (prom_strstr(p, "Power Macintosh") ||

			    prom_strstr(p, "MacRISC"))

				return PLATFORM_POWERMAC;

#ifdef CONFIG_PPC64

			/* We must make sure we don't detect the IBM Cell

			 * blades as pSeries due to some firmware issues,

			 * so we do it here.

			 */

			if (strstr(p, "IBM,CBEA") ||

			    strstr(p, "IBM,CPBW-1.0"))

			if (prom_strstr(p, "IBM,CBEA") ||

			    prom_strstr(p, "IBM,CPBW-1.0"))

				return PLATFORM_GENERIC;

#endif /* CONFIG_PPC64 */

			i += sl + 1;
@@ -2090,7 +2219,7 @@ static int __init prom_find_machine_type(void) 
			   compat, sizeof(compat)-1);

	if (len <= 0)

		return PLATFORM_GENERIC;

	if (strcmp(compat, "chrp"))

	if (prom_strcmp(compat, "chrp"))

		return PLATFORM_GENERIC;



	/* Default to pSeries. We need to know if we are running LPAR */
@@ -2152,7 +2281,7 @@ static void __init prom_check_displays(void) 
	for (node = 0; prom_next_node(&node); ) {

		memset(type, 0, sizeof(type));

		prom_getprop(node, "device_type", type, sizeof(type));

		if (strcmp(type, "display") != 0)

		if (prom_strcmp(type, "display") != 0)

			continue;



		/* It seems OF doesn't null-terminate the path :-( */
@@ -2256,9 +2385,9 @@ static unsigned long __init dt_find_string(char *str) 
	s = os = (char *)dt_string_start;

	s += 4;

	while (s <  (char *)dt_string_end) {

		if (strcmp(s, str) == 0)

		if (prom_strcmp(s, str) == 0)

			return s - os;

		s += strlen(s) + 1;

		s += prom_strlen(s) + 1;

	}

	return 0;

}
@@ -2291,7 +2420,7 @@ static void __init scan_dt_build_strings(phandle node, 
		}



 		/* skip "name" */

 		if (strcmp(namep, "name") == 0) {

		if (prom_strcmp(namep, "name") == 0) {

 			*mem_start = (unsigned long)namep;

 			prev_name = "name";

 			continue;
@@ -2303,7 +2432,7 @@ static void __init scan_dt_build_strings(phandle node, 
			namep = sstart + soff;

		} else {

			/* Trim off some if we can */

			*mem_start = (unsigned long)namep + strlen(namep) + 1;

			*mem_start = (unsigned long)namep + prom_strlen(namep) + 1;

			dt_string_end = *mem_start;

		}

		prev_name = namep;
@@ -2372,7 +2501,7 @@ static void __init scan_dt_build_struct(phandle node, unsigned long *mem_start, 
			break;



 		/* skip "name" */

 		if (strcmp(pname, "name") == 0) {

		if (prom_strcmp(pname, "name") == 0) {

 			prev_name = "name";

 			continue;

 		}
@@ -2403,7 +2532,7 @@ static void __init scan_dt_build_struct(phandle node, unsigned long *mem_start, 
		call_prom("getprop", 4, 1, node, pname, valp, l);

		*mem_start = _ALIGN(*mem_start, 4);



		if (!strcmp(pname, "phandle"))

		if (!prom_strcmp(pname, "phandle"))

			has_phandle = 1;

	}
@@ -2473,8 +2602,8 @@ static void __init flatten_device_tree(void) 


	/* Add "phandle" in there, we'll need it */

	namep = make_room(&mem_start, &mem_end, 16, 1);

	strcpy(namep, "phandle");

	mem_start = (unsigned long)namep + strlen(namep) + 1;

	prom_strcpy(namep, "phandle");

	mem_start = (unsigned long)namep + prom_strlen(namep) + 1;



	/* Build string array */

	prom_printf("Building dt strings...\n");
@@ -2796,7 +2925,7 @@ static void __init fixup_device_tree_efika(void) 
	rv = prom_getprop(node, "model", prop, sizeof(prop));

	if (rv == PROM_ERROR)

		return;

	if (strcmp(prop, "EFIKA5K2"))

	if (prom_strcmp(prop, "EFIKA5K2"))

		return;



	prom_printf("Applying EFIKA device tree fixups\n");
@@ -2804,13 +2933,13 @@ static void __init fixup_device_tree_efika(void) 
	/* Claiming to be 'chrp' is death */

	node = call_prom("finddevice", 1, 1, ADDR("/"));

	rv = prom_getprop(node, "device_type", prop, sizeof(prop));

	if (rv != PROM_ERROR && (strcmp(prop, "chrp") == 0))

	if (rv != PROM_ERROR && (prom_strcmp(prop, "chrp") == 0))

		prom_setprop(node, "/", "device_type", "efika", sizeof("efika"));



	/* CODEGEN,description is exposed in /proc/cpuinfo so

	   fix that too */

	rv = prom_getprop(node, "CODEGEN,description", prop, sizeof(prop));

	if (rv != PROM_ERROR && (strstr(prop, "CHRP")))

	if (rv != PROM_ERROR && (prom_strstr(prop, "CHRP")))

		prom_setprop(node, "/", "CODEGEN,description",

			     "Efika 5200B PowerPC System",

			     sizeof("Efika 5200B PowerPC System"));

arch/powerpc/kernel/prom_init_check.sh

+1 −1
Original line number Diff line number Diff line
@@ -27,7 +27,7 @@ fi 
WHITELIST="add_reloc_offset __bss_start __bss_stop copy_and_flush

_end enter_prom $MEM_FUNCS reloc_offset __secondary_hold

__secondary_hold_acknowledge __secondary_hold_spinloop __start

strcmp strcpy strlcpy strlen strncmp strstr kstrtobool logo_linux_clut224

logo_linux_clut224

reloc_got2 kernstart_addr memstart_addr linux_banner _stext

__prom_init_toc_start __prom_init_toc_end btext_setup_display TOC."

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