From 1ce53adf13a54375d2a5c7cdbe341b2558389615 Mon Sep 17 00:00:00 2001 From: Denys Vlasenko Date: Thu, 29 Jul 2010 01:47:53 +0200 Subject: modpost: support objects with more than 64k sections This patch makes modpost able to process object files with more than 64k sections. Needed for huge kernel builds (allyesconfig, for example) with -ffunction-sections. 64k sections handling is covered, for example, by this document: "IA-64 gABI Proposal 74: Section Indexes" http://www.codesourcery.com/public/cxx-abi/abi/prop-74-sindex.html Signed-off-by: Denys Vlasenko Signed-off-by: Anders Kaseorg Acked-by: Sam Ravnborg Cc: Rusty Russell Cc: Andi Kleen Signed-off-by: Michal Marek --- scripts/mod/modpost.c | 102 +++++++++++++++++++++++++++++++++++++------------- 1 file changed, 76 insertions(+), 26 deletions(-) (limited to 'scripts/mod/modpost.c') diff --git a/scripts/mod/modpost.c b/scripts/mod/modpost.c index 3318692e4e7..7249ab44f44 100644 --- a/scripts/mod/modpost.c +++ b/scripts/mod/modpost.c @@ -253,7 +253,7 @@ static enum export export_no(const char *s) return export_unknown; } -static enum export export_from_sec(struct elf_info *elf, Elf_Section sec) +static enum export export_from_sec(struct elf_info *elf, unsigned int sec) { if (sec == elf->export_sec) return export_plain; @@ -373,6 +373,8 @@ static int parse_elf(struct elf_info *info, const char *filename) Elf_Ehdr *hdr; Elf_Shdr *sechdrs; Elf_Sym *sym; + const char *secstrings; + unsigned int symtab_idx = ~0U, symtab_shndx_idx = ~0U; hdr = grab_file(filename, &info->size); if (!hdr) { @@ -417,8 +419,27 @@ static int parse_elf(struct elf_info *info, const char *filename) return 0; } + if (hdr->e_shnum == 0) { + /* + * There are more than 64k sections, + * read count from .sh_size. + * note: it doesn't need shndx2secindex() + */ + info->num_sections = TO_NATIVE(sechdrs[0].sh_size); + } + else { + info->num_sections = hdr->e_shnum; + } + if (hdr->e_shstrndx == SHN_XINDEX) { + info->secindex_strings = + shndx2secindex(TO_NATIVE(sechdrs[0].sh_link)); + } + else { + info->secindex_strings = hdr->e_shstrndx; + } + /* Fix endianness in section headers */ - for (i = 0; i < hdr->e_shnum; i++) { + for (i = 0; i < info->num_sections; i++) { sechdrs[i].sh_name = TO_NATIVE(sechdrs[i].sh_name); sechdrs[i].sh_type = TO_NATIVE(sechdrs[i].sh_type); sechdrs[i].sh_flags = TO_NATIVE(sechdrs[i].sh_flags); @@ -431,9 +452,8 @@ static int parse_elf(struct elf_info *info, const char *filename) sechdrs[i].sh_entsize = TO_NATIVE(sechdrs[i].sh_entsize); } /* Find symbol table. */ - for (i = 1; i < hdr->e_shnum; i++) { - const char *secstrings - = (void *)hdr + sechdrs[hdr->e_shstrndx].sh_offset; + secstrings = (void *)hdr + sechdrs[info->secindex_strings].sh_offset; + for (i = 1; i < info->num_sections; i++) { const char *secname; int nobits = sechdrs[i].sh_type == SHT_NOBITS; @@ -461,14 +481,26 @@ static int parse_elf(struct elf_info *info, const char *filename) else if (strcmp(secname, "__ksymtab_gpl_future") == 0) info->export_gpl_future_sec = i; - if (sechdrs[i].sh_type != SHT_SYMTAB) - continue; + if (sechdrs[i].sh_type == SHT_SYMTAB) { + unsigned int sh_link_idx; + symtab_idx = i; + info->symtab_start = (void *)hdr + + sechdrs[i].sh_offset; + info->symtab_stop = (void *)hdr + + sechdrs[i].sh_offset + sechdrs[i].sh_size; + sh_link_idx = shndx2secindex(sechdrs[i].sh_link); + info->strtab = (void *)hdr + + sechdrs[sh_link_idx].sh_offset; + } - info->symtab_start = (void *)hdr + sechdrs[i].sh_offset; - info->symtab_stop = (void *)hdr + sechdrs[i].sh_offset - + sechdrs[i].sh_size; - info->strtab = (void *)hdr + - sechdrs[sechdrs[i].sh_link].sh_offset; + /* 32bit section no. table? ("more than 64k sections") */ + if (sechdrs[i].sh_type == SHT_SYMTAB_SHNDX) { + symtab_shndx_idx = i; + info->symtab_shndx_start = (void *)hdr + + sechdrs[i].sh_offset; + info->symtab_shndx_stop = (void *)hdr + + sechdrs[i].sh_offset + sechdrs[i].sh_size; + } } if (!info->symtab_start) fatal("%s has no symtab?\n", filename); @@ -480,6 +512,21 @@ static int parse_elf(struct elf_info *info, const char *filename) sym->st_value = TO_NATIVE(sym->st_value); sym->st_size = TO_NATIVE(sym->st_size); } + + if (symtab_shndx_idx != ~0U) { + Elf32_Word *p; + if (symtab_idx != + shndx2secindex(sechdrs[symtab_shndx_idx].sh_link)) + fatal("%s: SYMTAB_SHNDX has bad sh_link: %u!=%u\n", + filename, + shndx2secindex(sechdrs[symtab_shndx_idx].sh_link), + symtab_idx); + /* Fix endianness */ + for (p = info->symtab_shndx_start; p < info->symtab_shndx_stop; + p++) + *p = TO_NATIVE(*p); + } + return 1; } @@ -514,7 +561,7 @@ static void handle_modversions(struct module *mod, struct elf_info *info, Elf_Sym *sym, const char *symname) { unsigned int crc; - enum export export = export_from_sec(info, sym->st_shndx); + enum export export = export_from_sec(info, get_secindex(info, sym)); switch (sym->st_shndx) { case SHN_COMMON: @@ -656,19 +703,19 @@ static const char *sym_name(struct elf_info *elf, Elf_Sym *sym) return "(unknown)"; } -static const char *sec_name(struct elf_info *elf, int shndx) +static const char *sec_name(struct elf_info *elf, int secindex) { Elf_Shdr *sechdrs = elf->sechdrs; return (void *)elf->hdr + - elf->sechdrs[elf->hdr->e_shstrndx].sh_offset + - sechdrs[shndx].sh_name; + elf->sechdrs[elf->secindex_strings].sh_offset + + sechdrs[secindex].sh_name; } static const char *sech_name(struct elf_info *elf, Elf_Shdr *sechdr) { return (void *)elf->hdr + - elf->sechdrs[elf->hdr->e_shstrndx].sh_offset + - sechdr->sh_name; + elf->sechdrs[elf->secindex_strings].sh_offset + + sechdr->sh_name; } /* if sym is empty or point to a string @@ -1047,11 +1094,14 @@ static Elf_Sym *find_elf_symbol(struct elf_info *elf, Elf64_Sword addr, Elf_Sym *near = NULL; Elf64_Sword distance = 20; Elf64_Sword d; + unsigned int relsym_secindex; if (relsym->st_name != 0) return relsym; + + relsym_secindex = get_secindex(elf, relsym); for (sym = elf->symtab_start; sym < elf->symtab_stop; sym++) { - if (sym->st_shndx != relsym->st_shndx) + if (get_secindex(elf, sym) != relsym_secindex) continue; if (ELF_ST_TYPE(sym->st_info) == STT_SECTION) continue; @@ -1113,9 +1163,9 @@ static Elf_Sym *find_elf_symbol2(struct elf_info *elf, Elf_Addr addr, for (sym = elf->symtab_start; sym < elf->symtab_stop; sym++) { const char *symsec; - if (sym->st_shndx >= SHN_LORESERVE) + if (is_shndx_special(sym->st_shndx)) continue; - symsec = sec_name(elf, sym->st_shndx); + symsec = sec_name(elf, get_secindex(elf, sym)); if (strcmp(symsec, sec) != 0) continue; if (!is_valid_name(elf, sym)) @@ -1311,7 +1361,7 @@ static void check_section_mismatch(const char *modname, struct elf_info *elf, const char *tosec; const struct sectioncheck *mismatch; - tosec = sec_name(elf, sym->st_shndx); + tosec = sec_name(elf, get_secindex(elf, sym)); mismatch = section_mismatch(fromsec, tosec); if (mismatch) { Elf_Sym *to; @@ -1339,7 +1389,7 @@ static unsigned int *reloc_location(struct elf_info *elf, Elf_Shdr *sechdr, Elf_Rela *r) { Elf_Shdr *sechdrs = elf->sechdrs; - int section = sechdr->sh_info; + int section = shndx2secindex(sechdr->sh_info); return (void *)elf->hdr + sechdrs[section].sh_offset + (r->r_offset - sechdrs[section].sh_addr); @@ -1447,7 +1497,7 @@ static void section_rela(const char *modname, struct elf_info *elf, r.r_addend = TO_NATIVE(rela->r_addend); sym = elf->symtab_start + r_sym; /* Skip special sections */ - if (sym->st_shndx >= SHN_LORESERVE) + if (is_shndx_special(sym->st_shndx)) continue; check_section_mismatch(modname, elf, &r, sym, fromsec); } @@ -1505,7 +1555,7 @@ static void section_rel(const char *modname, struct elf_info *elf, } sym = elf->symtab_start + r_sym; /* Skip special sections */ - if (sym->st_shndx >= SHN_LORESERVE) + if (is_shndx_special(sym->st_shndx)) continue; check_section_mismatch(modname, elf, &r, sym, fromsec); } @@ -1530,7 +1580,7 @@ static void check_sec_ref(struct module *mod, const char *modname, Elf_Shdr *sechdrs = elf->sechdrs; /* Walk through all sections */ - for (i = 0; i < elf->hdr->e_shnum; i++) { + for (i = 0; i < elf->num_sections; i++) { check_section(modname, elf, &elf->sechdrs[i]); /* We want to process only relocation sections and not .init */ if (sechdrs[i].sh_type == SHT_RELA) -- cgit v1.2.3-70-g09d2 From 37ed19d5cce35a40d3913cf9aa208ce9f60db3d7 Mon Sep 17 00:00:00 2001 From: Alexey Fomenko Date: Mon, 9 Aug 2010 17:20:24 -0700 Subject: scripts/mod/modpost.c: fix memory leak sec2annotation returns malloc'ed buffer directly to printf as an argument. Free this buffer after printing. Signed-off-by: Alexey Fomenko Cc: Trevor Keith Cc: Rusty Russell Cc: Michal Marek Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- scripts/mod/modpost.c | 54 ++++++++++++++++++++++++++++++++++++++------------- 1 file changed, 40 insertions(+), 14 deletions(-) (limited to 'scripts/mod/modpost.c') diff --git a/scripts/mod/modpost.c b/scripts/mod/modpost.c index c827309c29c..1ce655dde99 100644 --- a/scripts/mod/modpost.c +++ b/scripts/mod/modpost.c @@ -1245,6 +1245,8 @@ static void report_sec_mismatch(const char *modname, { const char *from, *from_p; const char *to, *to_p; + char *prl_from; + char *prl_to; switch (from_is_func) { case 0: from = "variable"; from_p = ""; break; @@ -1268,16 +1270,21 @@ static void report_sec_mismatch(const char *modname, switch (mismatch->mismatch) { case TEXT_TO_ANY_INIT: + prl_from = sec2annotation(fromsec); + prl_to = sec2annotation(tosec); fprintf(stderr, "The function %s%s() references\n" "the %s %s%s%s.\n" "This is often because %s lacks a %s\n" "annotation or the annotation of %s is wrong.\n", - sec2annotation(fromsec), fromsym, - to, sec2annotation(tosec), tosym, to_p, - fromsym, sec2annotation(tosec), tosym); + prl_from, fromsym, + to, prl_to, tosym, to_p, + fromsym, prl_to, tosym); + free(prl_from); + free(prl_to); break; case DATA_TO_ANY_INIT: { + prl_to = sec2annotation(tosec); const char *const *s = mismatch->symbol_white_list; fprintf(stderr, "The variable %s references\n" @@ -1285,20 +1292,24 @@ static void report_sec_mismatch(const char *modname, "If the reference is valid then annotate the\n" "variable with __init* or __refdata (see linux/init.h) " "or name the variable:\n", - fromsym, to, sec2annotation(tosec), tosym, to_p); + fromsym, to, prl_to, tosym, to_p); while (*s) fprintf(stderr, "%s, ", *s++); fprintf(stderr, "\n"); + free(prl_to); break; } case TEXT_TO_ANY_EXIT: + prl_to = sec2annotation(tosec); fprintf(stderr, "The function %s() references a %s in an exit section.\n" "Often the %s %s%s has valid usage outside the exit section\n" "and the fix is to remove the %sannotation of %s.\n", - fromsym, to, to, tosym, to_p, sec2annotation(tosec), tosym); + fromsym, to, to, tosym, to_p, prl_to, tosym); + free(prl_to); break; case DATA_TO_ANY_EXIT: { + prl_to = sec2annotation(tosec); const char *const *s = mismatch->symbol_white_list; fprintf(stderr, "The variable %s references\n" @@ -1306,24 +1317,31 @@ static void report_sec_mismatch(const char *modname, "If the reference is valid then annotate the\n" "variable with __exit* (see linux/init.h) or " "name the variable:\n", - fromsym, to, sec2annotation(tosec), tosym, to_p); + fromsym, to, prl_to, tosym, to_p); while (*s) fprintf(stderr, "%s, ", *s++); fprintf(stderr, "\n"); + free(prl_to); break; } case XXXINIT_TO_SOME_INIT: case XXXEXIT_TO_SOME_EXIT: + prl_from = sec2annotation(fromsec); + prl_to = sec2annotation(tosec); fprintf(stderr, "The %s %s%s%s references\n" "a %s %s%s%s.\n" "If %s is only used by %s then\n" "annotate %s with a matching annotation.\n", - from, sec2annotation(fromsec), fromsym, from_p, - to, sec2annotation(tosec), tosym, to_p, + from, prl_from, fromsym, from_p, + to, prl_to, tosym, to_p, tosym, fromsym, tosym); + free(prl_from); + free(prl_to); break; case ANY_INIT_TO_ANY_EXIT: + prl_from = sec2annotation(fromsec); + prl_to = sec2annotation(tosec); fprintf(stderr, "The %s %s%s%s references\n" "a %s %s%s%s.\n" @@ -1332,11 +1350,15 @@ static void report_sec_mismatch(const char *modname, "uses functionality in the exit path.\n" "The fix is often to remove the %sannotation of\n" "%s%s so it may be used outside an exit section.\n", - from, sec2annotation(fromsec), fromsym, from_p, - to, sec2annotation(tosec), tosym, to_p, + from, prl_from, fromsym, from_p, + to, prl_to, tosym, to_p, sec2annotation(tosec), tosym, to_p); + free(prl_from); + free(prl_to); break; case ANY_EXIT_TO_ANY_INIT: + prl_from = sec2annotation(fromsec); + prl_to = sec2annotation(tosec); fprintf(stderr, "The %s %s%s%s references\n" "a %s %s%s%s.\n" @@ -1345,16 +1367,20 @@ static void report_sec_mismatch(const char *modname, "uses functionality in the init path.\n" "The fix is often to remove the %sannotation of\n" "%s%s so it may be used outside an init section.\n", - from, sec2annotation(fromsec), fromsym, from_p, - to, sec2annotation(tosec), tosym, to_p, - sec2annotation(tosec), tosym, to_p); + from, prl_from, fromsym, from_p, + to, prl_to, tosym, to_p, + prl_to, tosym, to_p); + free(prl_from); + free(prl_to); break; case EXPORT_TO_INIT_EXIT: + prl_to = sec2annotation(tosec); fprintf(stderr, "The symbol %s is exported and annotated %s\n" "Fix this by removing the %sannotation of %s " "or drop the export.\n", - tosym, sec2annotation(tosec), sec2annotation(tosec), tosym); + tosym, prl_to, prl_to, tosym); + free(prl_to); break; } fprintf(stderr, "\n"); -- cgit v1.2.3-70-g09d2 From 6a841528d288ac420052f5c98fd426b0fcdc5b52 Mon Sep 17 00:00:00 2001 From: Rusty Russell Date: Wed, 11 Aug 2010 23:04:16 -0600 Subject: param: silence .init.text references from param ops Ideally, we'd check that it was only the "set" function which was __init, and that the permissions were r/o. But that's a little hard. Signed-off-by: Rusty Russell Acked-by: Sam Ravnborg Tested-by: Phil Carmody --- scripts/mod/modpost.c | 13 +++++++++++++ 1 file changed, 13 insertions(+) (limited to 'scripts/mod/modpost.c') diff --git a/scripts/mod/modpost.c b/scripts/mod/modpost.c index 1ce655dde99..b16044002d9 100644 --- a/scripts/mod/modpost.c +++ b/scripts/mod/modpost.c @@ -1033,6 +1033,13 @@ static const struct sectioncheck *section_mismatch( * fromsec = .data* * atsym =__param* * + * Pattern 1a: + * module_param_call() ops can refer to __init set function if permissions=0 + * The pattern is identified by: + * tosec = .init.text + * fromsec = .data* + * atsym = __param_ops_* + * * Pattern 2: * Many drivers utilise a *driver container with references to * add, remove, probe functions etc. @@ -1067,6 +1074,12 @@ static int secref_whitelist(const struct sectioncheck *mismatch, (strncmp(fromsym, "__param", strlen("__param")) == 0)) return 0; + /* Check for pattern 1a */ + if (strcmp(tosec, ".init.text") == 0 && + match(fromsec, data_sections) && + (strncmp(fromsym, "__param_ops_", strlen("__param_ops_")) == 0)) + return 0; + /* Check for pattern 2 */ if (match(tosec, init_exit_sections) && match(fromsec, data_sections) && -- cgit v1.2.3-70-g09d2 From 5003bab82d56754b27be01eef24495a02e00039d Mon Sep 17 00:00:00 2001 From: Andrew Morton Date: Wed, 11 Aug 2010 00:42:26 -0700 Subject: fix "scripts/mod/modpost.c: fix memory leak" Fix error introduced by 37ed19d5cce35a40d3913cf9aa208ce9f60db3d7 ("scripts/mod/modpost.c: fix memory leak"). - don't kfree("") - fix one missed conversion Reported-by: Stephen Rothwell Tested-by: Stephen Rothwell Cc: Alexey Fomenko Cc: Trevor Keith Cc: Rusty Russell Cc: Michal Marek Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- scripts/mod/modpost.c | 5 +++-- 1 file changed, 3 insertions(+), 2 deletions(-) (limited to 'scripts/mod/modpost.c') diff --git a/scripts/mod/modpost.c b/scripts/mod/modpost.c index 1ce655dde99..7acbdd8fcae 100644 --- a/scripts/mod/modpost.c +++ b/scripts/mod/modpost.c @@ -14,6 +14,7 @@ #define _GNU_SOURCE #include #include +#include #include "modpost.h" #include "../../include/generated/autoconf.h" #include "../../include/linux/license.h" @@ -1217,7 +1218,7 @@ static char *sec2annotation(const char *s) strcat(p, " "); return r; /* we leak her but we do not care */ } else { - return ""; + return strdup(""); } } @@ -1352,7 +1353,7 @@ static void report_sec_mismatch(const char *modname, "%s%s so it may be used outside an exit section.\n", from, prl_from, fromsym, from_p, to, prl_to, tosym, to_p, - sec2annotation(tosec), tosym, to_p); + prl_to, tosym, to_p); free(prl_from); free(prl_to); break; -- cgit v1.2.3-70-g09d2 From 019fca84e7c4b94817abc77df9081ba208fcc46a Mon Sep 17 00:00:00 2001 From: David Howells Date: Thu, 12 Aug 2010 16:54:47 +0100 Subject: MN10300: Permit .GCC-command-line sections Permit .GCC-command-line sections in modules. Otherwise modpost says things like: WARNING: drivers/mtd/chips/map_ram.o (.GCC-command-line): unexpected non-allocatable section. Did you forget to use "ax"/"aw" in a .S file? Note that for example contains section definitions for use in .S files. Signed-off-by: David Howells Signed-off-by: Linus Torvalds --- scripts/mod/modpost.c | 1 + 1 file changed, 1 insertion(+) (limited to 'scripts/mod/modpost.c') diff --git a/scripts/mod/modpost.c b/scripts/mod/modpost.c index 7acbdd8fcae..253c107b9a9 100644 --- a/scripts/mod/modpost.c +++ b/scripts/mod/modpost.c @@ -790,6 +790,7 @@ static const char *section_white_list[] = { ".comment*", ".debug*", + ".GCC-command-line", /* mn10300 */ ".mdebug*", /* alpha, score, mips etc. */ ".pdr", /* alpha, score, mips etc. */ ".stab*", -- cgit v1.2.3-70-g09d2