From 74c176ca2f1fe702f6e46d86f634685480094335 Mon Sep 17 00:00:00 2001 From: Ian Lance Taylor Date: Mon, 24 Aug 2020 13:06:52 -0700 Subject: [PATCH] libbacktrace: add Mach-O 64-bit FAT support libbacktrace/: * macho.c (MACH_O_MH_MAGIC_FAT_64): Define. (MACH_O_MH_CIGAM_FAT_64): Define. (struct macho_fat_arch_64): Define. (macho_add_fat): Add and use is_64 parameter. (macho_add): Recognize 64-bit fat files. --- libbacktrace/macho.c | 72 +++++++++++++++++++++++++++++++++----------- 1 file changed, 54 insertions(+), 18 deletions(-) diff --git a/libbacktrace/macho.c b/libbacktrace/macho.c index 3aea70cdbbe..bd737226ca6 100644 --- a/libbacktrace/macho.c +++ b/libbacktrace/macho.c @@ -75,7 +75,7 @@ struct macho_header_64 struct macho_header_fat { - uint32_t magic; /* Magic number (MACH_O_MH_MAGIC_FAT) */ + uint32_t magic; /* Magic number (MACH_O_MH_(MAGIC|CIGAM)_FAT(_64)?) */ uint32_t nfat_arch; /* Number of components */ }; @@ -85,6 +85,8 @@ struct macho_header_fat #define MACH_O_MH_MAGIC_64 0xfeedfacf #define MACH_O_MH_MAGIC_FAT 0xcafebabe #define MACH_O_MH_CIGAM_FAT 0xbebafeca +#define MACH_O_MH_MAGIC_FAT_64 0xcafebabf +#define MACH_O_MH_CIGAM_FAT_64 0xbfbafeca /* Value for the header filetype field. */ @@ -105,6 +107,20 @@ struct macho_fat_arch uint32_t align; /* Alignment of this entry */ }; +/* A component of a 64-bit fat file. This is used if the magic field + is MAGIC_FAT_64. This is only used when some file size or file + offset is too large to represent in the 32-bit format. */ + +struct macho_fat_arch_64 +{ + uint32_t cputype; /* CPU type */ + uint32_t cpusubtype; /* CPU subtype */ + uint64_t offset; /* File offset of this entry */ + uint64_t size; /* Size of this entry */ + uint32_t align; /* Alignment of this entry */ + uint32_t reserved; /* Reserved */ +}; + /* Values for the fat_arch cputype field (and the header cputype field). */ @@ -740,14 +756,14 @@ static int macho_add_fat (struct backtrace_state *state, const char *filename, int descriptor, int swapped, off_t offset, const unsigned char *match_uuid, uintptr_t base_address, - int skip_symtab, uint32_t nfat_arch, + int skip_symtab, uint32_t nfat_arch, int is_64, backtrace_error_callback error_callback, void *data, fileline *fileline_fn, int *found_sym) { int arch_view_valid; unsigned int cputype; + size_t arch_size; struct backtrace_view arch_view; - size_t archoffset; unsigned int i; arch_view_valid = 0; @@ -765,21 +781,39 @@ macho_add_fat (struct backtrace_state *state, const char *filename, goto fail; #endif + if (is_64) + arch_size = sizeof (struct macho_fat_arch_64); + else + arch_size = sizeof (struct macho_fat_arch); + if (!backtrace_get_view (state, descriptor, offset, - nfat_arch * sizeof (struct macho_fat_arch), + nfat_arch * arch_size, error_callback, data, &arch_view)) goto fail; - archoffset = 0; for (i = 0; i < nfat_arch; ++i) { - struct macho_fat_arch fat_arch; + struct macho_fat_arch_64 fat_arch; uint32_t fcputype; - memcpy (&fat_arch, - ((const char *) arch_view.data - + i * sizeof (struct macho_fat_arch)), - sizeof fat_arch); + if (is_64) + memcpy (&fat_arch, + (const char *) arch_view.data + i * arch_size, + arch_size); + else + { + struct macho_fat_arch fat_arch_32; + + memcpy (&fat_arch_32, + (const char *) arch_view.data + i * arch_size, + arch_size); + fat_arch.cputype = fat_arch_32.cputype; + fat_arch.cpusubtype = fat_arch_32.cpusubtype; + fat_arch.offset = (uint64_t) fat_arch_32.offset; + fat_arch.size = (uint64_t) fat_arch_32.size; + fat_arch.align = fat_arch_32.align; + fat_arch.reserved = 0; + } fcputype = fat_arch.cputype; if (swapped) @@ -787,19 +821,17 @@ macho_add_fat (struct backtrace_state *state, const char *filename, if (fcputype == cputype) { - uint32_t foffset; + uint64_t foffset; /* FIXME: What about cpusubtype? */ foffset = fat_arch.offset; if (swapped) - foffset = __builtin_bswap32 (foffset); + foffset = __builtin_bswap64 (foffset); backtrace_release_view (state, &arch_view, error_callback, data); return macho_add (state, filename, descriptor, foffset, match_uuid, base_address, skip_symtab, error_callback, data, fileline_fn, found_sym); } - - archoffset += sizeof (struct macho_fat_arch); } error_callback (data, "could not find executable in fat file", 0); @@ -980,6 +1012,7 @@ macho_add (struct backtrace_state *state, const char *filename, int descriptor, hdroffset = offset + sizeof (struct macho_header_64); break; case MACH_O_MH_MAGIC_FAT: + case MACH_O_MH_MAGIC_FAT_64: { struct macho_header_fat fat_header; @@ -987,10 +1020,12 @@ macho_add (struct backtrace_state *state, const char *filename, int descriptor, memcpy (&fat_header, &header, sizeof fat_header); return macho_add_fat (state, filename, descriptor, 0, hdroffset, match_uuid, base_address, skip_symtab, - fat_header.nfat_arch, error_callback, data, - fileline_fn, found_sym); + fat_header.nfat_arch, + header.magic == MACH_O_MH_MAGIC_FAT_64, + error_callback, data, fileline_fn, found_sym); } case MACH_O_MH_CIGAM_FAT: + case MACH_O_MH_CIGAM_FAT_64: { struct macho_header_fat fat_header; uint32_t nfat_arch; @@ -1000,8 +1035,9 @@ macho_add (struct backtrace_state *state, const char *filename, int descriptor, nfat_arch = __builtin_bswap32 (fat_header.nfat_arch); return macho_add_fat (state, filename, descriptor, 1, hdroffset, match_uuid, base_address, skip_symtab, - nfat_arch, error_callback, data, - fileline_fn, found_sym); + nfat_arch, + header.magic == MACH_O_MH_CIGAM_FAT_64, + error_callback, data, fileline_fn, found_sym); } default: error_callback (data, "executable file is not in Mach-O format", 0); -- 2.30.2