From 450e7dd4001f22f796e22422dd1d2cbd5bda21fc Mon Sep 17 00:00:00 2001 From: Christophe Leroy Date: Fri, 26 Apr 2019 16:23:28 +0000 Subject: [PATCH] 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: Christophe Leroy Signed-off-by: Michael Ellerman --- arch/powerpc/kernel/prom_init.c | 211 ++++++++++++++++++++----- arch/powerpc/kernel/prom_init_check.sh | 2 +- 2 files changed, 171 insertions(+), 42 deletions(-) diff --git a/arch/powerpc/kernel/prom_init.c b/arch/powerpc/kernel/prom_init.c index ecf083c46bdb..7017156168e8 100644 --- a/arch/powerpc/kernel/prom_init.c +++ b/arch/powerpc/kernel/prom_init.c @@ -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")); diff --git a/arch/powerpc/kernel/prom_init_check.sh b/arch/powerpc/kernel/prom_init_check.sh index 181fd10008ef..4cac45cb5de5 100644 --- a/arch/powerpc/kernel/prom_init_check.sh +++ b/arch/powerpc/kernel/prom_init_check.sh @@ -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." -- GitLab