File:  [Qemu by Fabrice Bellard] / qemu / linux-user / flatload.c
Revision 1.1.1.7 (vendor branch): download - view: text, annotated - select for diffs
Tue Apr 24 18:35:47 2018 UTC (3 years, 3 months ago) by root
Branches: qemu, MAIN
CVS tags: qemu0150, qemu0141, qemu0140, HEAD
qemu 0.14.0

    1: /****************************************************************************/
    2: /*
    3:  *  QEMU bFLT binary loader.  Based on linux/fs/binfmt_flat.c
    4:  *
    5:  *  This program is free software; you can redistribute it and/or modify
    6:  *  it under the terms of the GNU General Public License as published by
    7:  *  the Free Software Foundation; either version 2 of the License, or
    8:  *  (at your option) any later version.
    9:  *
   10:  *  This program is distributed in the hope that it will be useful,
   11:  *  but WITHOUT ANY WARRANTY; without even the implied warranty of
   12:  *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
   13:  *  GNU General Public License for more details.
   14:  *
   15:  *  You should have received a copy of the GNU General Public License
   16:  *  along with this program; if not, see <http://www.gnu.org/licenses/>.
   17:  *
   18:  *      Copyright (C) 2006 CodeSourcery.
   19:  *	Copyright (C) 2000-2003 David McCullough <davidm@snapgear.com>
   20:  *	Copyright (C) 2002 Greg Ungerer <gerg@snapgear.com>
   21:  *	Copyright (C) 2002 SnapGear, by Paul Dale <pauli@snapgear.com>
   22:  *	Copyright (C) 2000, 2001 Lineo, by David McCullough <davidm@lineo.com>
   23:  *  based heavily on:
   24:  *
   25:  *  linux/fs/binfmt_aout.c:
   26:  *      Copyright (C) 1991, 1992, 1996  Linus Torvalds
   27:  *  linux/fs/binfmt_flat.c for 2.0 kernel
   28:  *	    Copyright (C) 1998  Kenneth Albanowski <kjahds@kjahds.com>
   29:  *	JAN/99 -- coded full program relocation (gerg@snapgear.com)
   30:  */
   31: 
   32: /* ??? ZFLAT and shared library support is currently disabled.  */
   33: 
   34: /****************************************************************************/
   35: 
   36: #include <stdio.h>
   37: #include <stdlib.h>
   38: #include <errno.h>
   39: #include <sys/mman.h>
   40: #include <unistd.h>
   41: 
   42: #include "qemu.h"
   43: #include "flat.h"
   44: 
   45: //#define DEBUG
   46: 
   47: #ifdef DEBUG
   48: #define	DBG_FLT(...)	printf(__VA_ARGS__)
   49: #else
   50: #define	DBG_FLT(...)
   51: #endif
   52: 
   53: #define flat_reloc_valid(reloc, size)             ((reloc) <= (size))
   54: #define flat_old_ram_flag(flag)                   (flag)
   55: #ifdef TARGET_WORDS_BIGENDIAN
   56: #define flat_get_relocate_addr(relval)            (relval)
   57: #else
   58: #define flat_get_relocate_addr(relval)            bswap32(relval)
   59: #endif
   60: 
   61: #define RELOC_FAILED 0xff00ff01		/* Relocation incorrect somewhere */
   62: #define UNLOADED_LIB 0x7ff000ff		/* Placeholder for unused library */
   63: 
   64: struct lib_info {
   65:     abi_ulong start_code;       /* Start of text segment */
   66:     abi_ulong start_data;       /* Start of data segment */
   67:     abi_ulong end_data;         /* Start of bss section */
   68:     abi_ulong start_brk;        /* End of data segment */
   69:     abi_ulong text_len;	        /* Length of text segment */
   70:     abi_ulong entry;	        /* Start address for this module */
   71:     abi_ulong build_date;       /* When this one was compiled */
   72:     short loaded;		/* Has this library been loaded? */
   73: };
   74: 
   75: #ifdef CONFIG_BINFMT_SHARED_FLAT
   76: static int load_flat_shared_library(int id, struct lib_info *p);
   77: #endif
   78: 
   79: struct linux_binprm;
   80: 
   81: #define ntohl(x) be32_to_cpu(x)
   82: 
   83: /****************************************************************************/
   84: /*
   85:  * create_flat_tables() parses the env- and arg-strings in new user
   86:  * memory and creates the pointer tables from them, and puts their
   87:  * addresses on the "stack", returning the new stack pointer value.
   88:  */
   89: 
   90: /* Push a block of strings onto the guest stack.  */
   91: static abi_ulong copy_strings(abi_ulong p, int n, char **s)
   92: {
   93:     int len;
   94: 
   95:     while (n-- > 0) {
   96:         len = strlen(s[n]) + 1;
   97:         p -= len;
   98:         memcpy_to_target(p, s[n], len);
   99:     }
  100: 
  101:     return p;
  102: }
  103: 
  104: static int target_pread(int fd, abi_ulong ptr, abi_ulong len,
  105:                         abi_ulong offset)
  106: {
  107:     void *buf;
  108:     int ret;
  109: 
  110:     buf = lock_user(VERIFY_WRITE, ptr, len, 0);
  111:     ret = pread(fd, buf, len, offset);
  112:     unlock_user(buf, ptr, len);
  113:     return ret;
  114: }
  115: /****************************************************************************/
  116: 
  117: #ifdef CONFIG_BINFMT_ZFLAT
  118: 
  119: #include <linux/zlib.h>
  120: 
  121: #define LBUFSIZE	4000
  122: 
  123: /* gzip flag byte */
  124: #define ASCII_FLAG   0x01 /* bit 0 set: file probably ASCII text */
  125: #define CONTINUATION 0x02 /* bit 1 set: continuation of multi-part gzip file */
  126: #define EXTRA_FIELD  0x04 /* bit 2 set: extra field present */
  127: #define ORIG_NAME    0x08 /* bit 3 set: original file name present */
  128: #define COMMENT      0x10 /* bit 4 set: file comment present */
  129: #define ENCRYPTED    0x20 /* bit 5 set: file is encrypted */
  130: #define RESERVED     0xC0 /* bit 6,7:   reserved */
  131: 
  132: static int decompress_exec(
  133: 	struct linux_binprm *bprm,
  134: 	unsigned long offset,
  135: 	char *dst,
  136: 	long len,
  137: 	int fd)
  138: {
  139: 	unsigned char *buf;
  140: 	z_stream strm;
  141: 	loff_t fpos;
  142: 	int ret, retval;
  143: 
  144: 	DBG_FLT("decompress_exec(offset=%x,buf=%x,len=%x)\n",(int)offset, (int)dst, (int)len);
  145: 
  146: 	memset(&strm, 0, sizeof(strm));
  147: 	strm.workspace = kmalloc(zlib_inflate_workspacesize(), GFP_KERNEL);
  148: 	if (strm.workspace == NULL) {
  149: 		DBG_FLT("binfmt_flat: no memory for decompress workspace\n");
  150: 		return -ENOMEM;
  151: 	}
  152: 	buf = kmalloc(LBUFSIZE, GFP_KERNEL);
  153: 	if (buf == NULL) {
  154: 		DBG_FLT("binfmt_flat: no memory for read buffer\n");
  155: 		retval = -ENOMEM;
  156: 		goto out_free;
  157: 	}
  158: 
  159: 	/* Read in first chunk of data and parse gzip header. */
  160: 	fpos = offset;
  161: 	ret = bprm->file->f_op->read(bprm->file, buf, LBUFSIZE, &fpos);
  162: 
  163: 	strm.next_in = buf;
  164: 	strm.avail_in = ret;
  165: 	strm.total_in = 0;
  166: 
  167: 	retval = -ENOEXEC;
  168: 
  169: 	/* Check minimum size -- gzip header */
  170: 	if (ret < 10) {
  171: 		DBG_FLT("binfmt_flat: file too small?\n");
  172: 		goto out_free_buf;
  173: 	}
  174: 
  175: 	/* Check gzip magic number */
  176: 	if ((buf[0] != 037) || ((buf[1] != 0213) && (buf[1] != 0236))) {
  177: 		DBG_FLT("binfmt_flat: unknown compression magic?\n");
  178: 		goto out_free_buf;
  179: 	}
  180: 
  181: 	/* Check gzip method */
  182: 	if (buf[2] != 8) {
  183: 		DBG_FLT("binfmt_flat: unknown compression method?\n");
  184: 		goto out_free_buf;
  185: 	}
  186: 	/* Check gzip flags */
  187: 	if ((buf[3] & ENCRYPTED) || (buf[3] & CONTINUATION) ||
  188: 	    (buf[3] & RESERVED)) {
  189: 		DBG_FLT("binfmt_flat: unknown flags?\n");
  190: 		goto out_free_buf;
  191: 	}
  192: 
  193: 	ret = 10;
  194: 	if (buf[3] & EXTRA_FIELD) {
  195: 		ret += 2 + buf[10] + (buf[11] << 8);
  196: 		if (unlikely(LBUFSIZE == ret)) {
  197: 			DBG_FLT("binfmt_flat: buffer overflow (EXTRA)?\n");
  198: 			goto out_free_buf;
  199: 		}
  200: 	}
  201: 	if (buf[3] & ORIG_NAME) {
  202: 		for (; ret < LBUFSIZE && (buf[ret] != 0); ret++)
  203: 			;
  204: 		if (unlikely(LBUFSIZE == ret)) {
  205: 			DBG_FLT("binfmt_flat: buffer overflow (ORIG_NAME)?\n");
  206: 			goto out_free_buf;
  207: 		}
  208: 	}
  209: 	if (buf[3] & COMMENT) {
  210: 		for (;  ret < LBUFSIZE && (buf[ret] != 0); ret++)
  211: 			;
  212: 		if (unlikely(LBUFSIZE == ret)) {
  213: 			DBG_FLT("binfmt_flat: buffer overflow (COMMENT)?\n");
  214: 			goto out_free_buf;
  215: 		}
  216: 	}
  217: 
  218: 	strm.next_in += ret;
  219: 	strm.avail_in -= ret;
  220: 
  221: 	strm.next_out = dst;
  222: 	strm.avail_out = len;
  223: 	strm.total_out = 0;
  224: 
  225: 	if (zlib_inflateInit2(&strm, -MAX_WBITS) != Z_OK) {
  226: 		DBG_FLT("binfmt_flat: zlib init failed?\n");
  227: 		goto out_free_buf;
  228: 	}
  229: 
  230: 	while ((ret = zlib_inflate(&strm, Z_NO_FLUSH)) == Z_OK) {
  231: 		ret = bprm->file->f_op->read(bprm->file, buf, LBUFSIZE, &fpos);
  232: 		if (ret <= 0)
  233: 			break;
  234: 		if (ret >= (unsigned long) -4096)
  235: 			break;
  236: 		len -= ret;
  237: 
  238: 		strm.next_in = buf;
  239: 		strm.avail_in = ret;
  240: 		strm.total_in = 0;
  241: 	}
  242: 
  243: 	if (ret < 0) {
  244: 		DBG_FLT("binfmt_flat: decompression failed (%d), %s\n",
  245: 			ret, strm.msg);
  246: 		goto out_zlib;
  247: 	}
  248: 
  249: 	retval = 0;
  250: out_zlib:
  251: 	zlib_inflateEnd(&strm);
  252: out_free_buf:
  253: 	kfree(buf);
  254: out_free:
  255: 	kfree(strm.workspace);
  256: out:
  257: 	return retval;
  258: }
  259: 
  260: #endif /* CONFIG_BINFMT_ZFLAT */
  261: 
  262: /****************************************************************************/
  263: 
  264: static abi_ulong
  265: calc_reloc(abi_ulong r, struct lib_info *p, int curid, int internalp)
  266: {
  267:     abi_ulong addr;
  268:     int id;
  269:     abi_ulong start_brk;
  270:     abi_ulong start_data;
  271:     abi_ulong text_len;
  272:     abi_ulong start_code;
  273: 
  274: #ifdef CONFIG_BINFMT_SHARED_FLAT
  275: #error needs checking
  276:     if (r == 0)
  277:         id = curid;	/* Relocs of 0 are always self referring */
  278:     else {
  279:         id = (r >> 24) & 0xff;	/* Find ID for this reloc */
  280:         r &= 0x00ffffff;	/* Trim ID off here */
  281:     }
  282:     if (id >= MAX_SHARED_LIBS) {
  283:         fprintf(stderr, "BINFMT_FLAT: reference 0x%x to shared library %d\n",
  284:                 (unsigned) r, id);
  285:         goto failed;
  286:     }
  287:     if (curid != id) {
  288:         if (internalp) {
  289:             fprintf(stderr, "BINFMT_FLAT: reloc address 0x%x not "
  290:                     "in same module (%d != %d)\n",
  291:                     (unsigned) r, curid, id);
  292:             goto failed;
  293:         } else if ( ! p[id].loaded &&
  294:                     load_flat_shared_library(id, p) > (unsigned long) -4096) {
  295:             fprintf(stderr, "BINFMT_FLAT: failed to load library %d\n", id);
  296:             goto failed;
  297:         }
  298:         /* Check versioning information (i.e. time stamps) */
  299:         if (p[id].build_date && p[curid].build_date
  300:             && p[curid].build_date < p[id].build_date) {
  301:             fprintf(stderr, "BINFMT_FLAT: library %d is younger than %d\n",
  302:                     id, curid);
  303:             goto failed;
  304:         }
  305:     }
  306: #else
  307:     id = 0;
  308: #endif
  309: 
  310:     start_brk = p[id].start_brk;
  311:     start_data = p[id].start_data;
  312:     start_code = p[id].start_code;
  313:     text_len = p[id].text_len;
  314: 
  315:     if (!flat_reloc_valid(r, start_brk - start_data + text_len)) {
  316:         fprintf(stderr, "BINFMT_FLAT: reloc outside program 0x%x "
  317:                 "(0 - 0x%x/0x%x)\n",
  318:                (int) r,(int)(start_brk-start_code),(int)text_len);
  319:         goto failed;
  320:     }
  321: 
  322:     if (r < text_len)			/* In text segment */
  323:         addr = r + start_code;
  324:     else					/* In data segment */
  325:         addr = r - text_len + start_data;
  326: 
  327:     /* Range checked already above so doing the range tests is redundant...*/
  328:     return(addr);
  329: 
  330: failed:
  331:     abort();
  332:     return RELOC_FAILED;
  333: }
  334: 
  335: /****************************************************************************/
  336: 
  337: /* ??? This does not handle endianness correctly.  */
  338: static void old_reloc(struct lib_info *libinfo, uint32_t rl)
  339: {
  340: #ifdef DEBUG
  341: 	const char *segment[] = { "TEXT", "DATA", "BSS", "*UNKNOWN*" };
  342: #endif
  343: 	uint32_t *ptr;
  344:         uint32_t offset;
  345:         int reloc_type;
  346: 
  347:         offset = rl & 0x3fffffff;
  348:         reloc_type = rl >> 30;
  349:         /* ??? How to handle this?  */
  350: #if defined(CONFIG_COLDFIRE)
  351: 	ptr = (uint32_t *) ((unsigned long) libinfo->start_code + offset);
  352: #else
  353: 	ptr = (uint32_t *) ((unsigned long) libinfo->start_data + offset);
  354: #endif
  355: 
  356: #ifdef DEBUG
  357: 	fprintf(stderr, "Relocation of variable at DATASEG+%x "
  358: 		"(address %p, currently %x) into segment %s\n",
  359: 		offset, ptr, (int)*ptr, segment[reloc_type]);
  360: #endif
  361: 
  362: 	switch (reloc_type) {
  363: 	case OLD_FLAT_RELOC_TYPE_TEXT:
  364: 		*ptr += libinfo->start_code;
  365: 		break;
  366: 	case OLD_FLAT_RELOC_TYPE_DATA:
  367: 		*ptr += libinfo->start_data;
  368: 		break;
  369: 	case OLD_FLAT_RELOC_TYPE_BSS:
  370: 		*ptr += libinfo->end_data;
  371: 		break;
  372: 	default:
  373: 		fprintf(stderr, "BINFMT_FLAT: Unknown relocation type=%x\n",
  374:                         reloc_type);
  375: 		break;
  376: 	}
  377: 	DBG_FLT("Relocation became %x\n", (int)*ptr);
  378: }
  379: 
  380: /****************************************************************************/
  381: 
  382: static int load_flat_file(struct linux_binprm * bprm,
  383: 		struct lib_info *libinfo, int id, abi_ulong *extra_stack)
  384: {
  385:     struct flat_hdr * hdr;
  386:     abi_ulong textpos = 0, datapos = 0;
  387:     abi_long result;
  388:     abi_ulong realdatastart = 0;
  389:     abi_ulong text_len, data_len, bss_len, stack_len, flags;
  390:     abi_ulong memp = 0; /* for finding the brk area */
  391:     abi_ulong extra;
  392:     abi_ulong reloc = 0, rp;
  393:     int i, rev, relocs = 0;
  394:     abi_ulong fpos;
  395:     abi_ulong start_code, end_code;
  396:     abi_ulong indx_len;
  397: 
  398:     hdr = ((struct flat_hdr *) bprm->buf);		/* exec-header */
  399: 
  400:     text_len  = ntohl(hdr->data_start);
  401:     data_len  = ntohl(hdr->data_end) - ntohl(hdr->data_start);
  402:     bss_len   = ntohl(hdr->bss_end) - ntohl(hdr->data_end);
  403:     stack_len = ntohl(hdr->stack_size);
  404:     if (extra_stack) {
  405:         stack_len += *extra_stack;
  406:         *extra_stack = stack_len;
  407:     }
  408:     relocs    = ntohl(hdr->reloc_count);
  409:     flags     = ntohl(hdr->flags);
  410:     rev       = ntohl(hdr->rev);
  411: 
  412:     DBG_FLT("BINFMT_FLAT: Loading file: %s\n", bprm->filename);
  413: 
  414:     if (rev != FLAT_VERSION && rev != OLD_FLAT_VERSION) {
  415:         fprintf(stderr, "BINFMT_FLAT: bad magic/rev (0x%x, need 0x%x)\n",
  416:                 rev, (int) FLAT_VERSION);
  417:         return -ENOEXEC;
  418:     }
  419: 
  420:     /* Don't allow old format executables to use shared libraries */
  421:     if (rev == OLD_FLAT_VERSION && id != 0) {
  422:         fprintf(stderr, "BINFMT_FLAT: shared libraries are not available\n");
  423:         return -ENOEXEC;
  424:     }
  425: 
  426:     /*
  427:      * fix up the flags for the older format,  there were all kinds
  428:      * of endian hacks,  this only works for the simple cases
  429:      */
  430:     if (rev == OLD_FLAT_VERSION && flat_old_ram_flag(flags))
  431:         flags = FLAT_FLAG_RAM;
  432: 
  433: #ifndef CONFIG_BINFMT_ZFLAT
  434:     if (flags & (FLAT_FLAG_GZIP|FLAT_FLAG_GZDATA)) {
  435:         fprintf(stderr, "Support for ZFLAT executables is not enabled\n");
  436:         return -ENOEXEC;
  437:     }
  438: #endif
  439: 
  440:     /*
  441:      * calculate the extra space we need to map in
  442:      */
  443:     extra = relocs * sizeof(abi_ulong);
  444:     if (extra < bss_len + stack_len)
  445:         extra = bss_len + stack_len;
  446: 
  447:     /* Add space for library base pointers.  Make sure this does not
  448:        misalign the  doesn't misalign the data segment.  */
  449:     indx_len = MAX_SHARED_LIBS * sizeof(abi_ulong);
  450:     indx_len = (indx_len + 15) & ~(abi_ulong)15;
  451: 
  452:     /*
  453:      * there are a couple of cases here,  the separate code/data
  454:      * case,  and then the fully copied to RAM case which lumps
  455:      * it all together.
  456:      */
  457:     if ((flags & (FLAT_FLAG_RAM|FLAT_FLAG_GZIP)) == 0) {
  458:         /*
  459:          * this should give us a ROM ptr,  but if it doesn't we don't
  460:          * really care
  461:          */
  462:         DBG_FLT("BINFMT_FLAT: ROM mapping of file (we hope)\n");
  463: 
  464:         textpos = target_mmap(0, text_len, PROT_READ|PROT_EXEC,
  465:                               MAP_PRIVATE, bprm->fd, 0);
  466:         if (textpos == -1) {
  467:             fprintf(stderr, "Unable to mmap process text\n");
  468:             return -1;
  469:         }
  470: 
  471:         realdatastart = target_mmap(0, data_len + extra + indx_len,
  472:                                     PROT_READ|PROT_WRITE|PROT_EXEC,
  473:                                     MAP_PRIVATE | MAP_ANONYMOUS, -1, 0);
  474: 
  475:         if (realdatastart == -1) {
  476:             fprintf(stderr, "Unable to allocate RAM for process data\n");
  477:             return realdatastart;
  478:         }
  479:         datapos = realdatastart + indx_len;
  480: 
  481:         DBG_FLT("BINFMT_FLAT: Allocated data+bss+stack (%d bytes): %x\n",
  482:                         (int)(data_len + bss_len + stack_len), (int)datapos);
  483: 
  484:         fpos = ntohl(hdr->data_start);
  485: #ifdef CONFIG_BINFMT_ZFLAT
  486:         if (flags & FLAT_FLAG_GZDATA) {
  487:             result = decompress_exec(bprm, fpos, (char *) datapos,
  488:                                      data_len + (relocs * sizeof(abi_ulong)))
  489:         } else
  490: #endif
  491:         {
  492:             result = target_pread(bprm->fd, datapos,
  493:                                   data_len + (relocs * sizeof(abi_ulong)),
  494:                                   fpos);
  495:         }
  496:         if (result < 0) {
  497:             fprintf(stderr, "Unable to read data+bss\n");
  498:             return result;
  499:         }
  500: 
  501:         reloc = datapos + (ntohl(hdr->reloc_start) - text_len);
  502:         memp = realdatastart;
  503: 
  504:     } else {
  505: 
  506:         textpos = target_mmap(0, text_len + data_len + extra + indx_len,
  507:                               PROT_READ | PROT_EXEC | PROT_WRITE,
  508:                               MAP_PRIVATE | MAP_ANONYMOUS, -1, 0);
  509:         if (textpos == -1 ) {
  510:             fprintf(stderr, "Unable to allocate RAM for process text/data\n");
  511:             return -1;
  512:         }
  513: 
  514:         realdatastart = textpos + ntohl(hdr->data_start);
  515:         datapos = realdatastart + indx_len;
  516:         reloc = (textpos + ntohl(hdr->reloc_start) + indx_len);
  517:         memp = textpos;
  518: 
  519: #ifdef CONFIG_BINFMT_ZFLAT
  520: #error code needs checking
  521:         /*
  522:          * load it all in and treat it like a RAM load from now on
  523:          */
  524:         if (flags & FLAT_FLAG_GZIP) {
  525:                 result = decompress_exec(bprm, sizeof (struct flat_hdr),
  526:                                  (((char *) textpos) + sizeof (struct flat_hdr)),
  527:                                  (text_len + data_len + (relocs * sizeof(unsigned long))
  528:                                           - sizeof (struct flat_hdr)),
  529:                                  0);
  530:                 memmove((void *) datapos, (void *) realdatastart,
  531:                                 data_len + (relocs * sizeof(unsigned long)));
  532:         } else if (flags & FLAT_FLAG_GZDATA) {
  533:                 fpos = 0;
  534:                 result = bprm->file->f_op->read(bprm->file,
  535:                                 (char *) textpos, text_len, &fpos);
  536:                 if (result < (unsigned long) -4096)
  537:                         result = decompress_exec(bprm, text_len, (char *) datapos,
  538:                                          data_len + (relocs * sizeof(unsigned long)), 0);
  539:         }
  540:         else
  541: #endif
  542:         {
  543:             result = target_pread(bprm->fd, textpos,
  544:                                   text_len, 0);
  545:             if (result >= 0) {
  546:                 result = target_pread(bprm->fd, datapos,
  547:                     data_len + (relocs * sizeof(abi_ulong)),
  548:                     ntohl(hdr->data_start));
  549:             }
  550:         }
  551:         if (result < 0) {
  552:             fprintf(stderr, "Unable to read code+data+bss\n");
  553:             return result;
  554:         }
  555:     }
  556: 
  557:     DBG_FLT("Mapping is 0x%x, Entry point is 0x%x, data_start is 0x%x\n",
  558:             (int)textpos, 0x00ffffff&ntohl(hdr->entry),
  559:             ntohl(hdr->data_start));
  560: 
  561:     /* The main program needs a little extra setup in the task structure */
  562:     start_code = textpos + sizeof (struct flat_hdr);
  563:     end_code = textpos + text_len;
  564: 
  565:     DBG_FLT("%s %s: TEXT=%x-%x DATA=%x-%x BSS=%x-%x\n",
  566:             id ? "Lib" : "Load", bprm->filename,
  567:             (int) start_code, (int) end_code,
  568:             (int) datapos,
  569:             (int) (datapos + data_len),
  570:             (int) (datapos + data_len),
  571:             (int) (((datapos + data_len + bss_len) + 3) & ~3));
  572: 
  573:     text_len -= sizeof(struct flat_hdr); /* the real code len */
  574: 
  575:     /* Store the current module values into the global library structure */
  576:     libinfo[id].start_code = start_code;
  577:     libinfo[id].start_data = datapos;
  578:     libinfo[id].end_data = datapos + data_len;
  579:     libinfo[id].start_brk = datapos + data_len + bss_len;
  580:     libinfo[id].text_len = text_len;
  581:     libinfo[id].loaded = 1;
  582:     libinfo[id].entry = (0x00ffffff & ntohl(hdr->entry)) + textpos;
  583:     libinfo[id].build_date = ntohl(hdr->build_date);
  584: 
  585:     /*
  586:      * We just load the allocations into some temporary memory to
  587:      * help simplify all this mumbo jumbo
  588:      *
  589:      * We've got two different sections of relocation entries.
  590:      * The first is the GOT which resides at the begining of the data segment
  591:      * and is terminated with a -1.  This one can be relocated in place.
  592:      * The second is the extra relocation entries tacked after the image's
  593:      * data segment. These require a little more processing as the entry is
  594:      * really an offset into the image which contains an offset into the
  595:      * image.
  596:      */
  597:     if (flags & FLAT_FLAG_GOTPIC) {
  598:         rp = datapos;
  599:         while (1) {
  600:             abi_ulong addr;
  601:             if (get_user_ual(addr, rp))
  602:                 return -EFAULT;
  603:             if (addr == -1)
  604:                 break;
  605:             if (addr) {
  606:                 addr = calc_reloc(addr, libinfo, id, 0);
  607:                 if (addr == RELOC_FAILED)
  608:                     return -ENOEXEC;
  609:                 if (put_user_ual(addr, rp))
  610:                     return -EFAULT;
  611:             }
  612:             rp += sizeof(abi_ulong);
  613:         }
  614:     }
  615: 
  616:     /*
  617:      * Now run through the relocation entries.
  618:      * We've got to be careful here as C++ produces relocatable zero
  619:      * entries in the constructor and destructor tables which are then
  620:      * tested for being not zero (which will always occur unless we're
  621:      * based from address zero).  This causes an endless loop as __start
  622:      * is at zero.  The solution used is to not relocate zero addresses.
  623:      * This has the negative side effect of not allowing a global data
  624:      * reference to be statically initialised to _stext (I've moved
  625:      * __start to address 4 so that is okay).
  626:      */
  627:     if (rev > OLD_FLAT_VERSION) {
  628:         for (i = 0; i < relocs; i++) {
  629:             abi_ulong addr, relval;
  630: 
  631:             /* Get the address of the pointer to be
  632:                relocated (of course, the address has to be
  633:                relocated first).  */
  634:             if (get_user_ual(relval, reloc + i * sizeof(abi_ulong)))
  635:                 return -EFAULT;
  636:             addr = flat_get_relocate_addr(relval);
  637:             rp = calc_reloc(addr, libinfo, id, 1);
  638:             if (rp == RELOC_FAILED)
  639:                 return -ENOEXEC;
  640: 
  641:             /* Get the pointer's value.  */
  642:             if (get_user_ual(addr, rp))
  643:                 return -EFAULT;
  644:             if (addr != 0) {
  645:                 /*
  646:                  * Do the relocation.  PIC relocs in the data section are
  647:                  * already in target order
  648:                  */
  649: 
  650: #ifndef TARGET_WORDS_BIGENDIAN
  651:                 if ((flags & FLAT_FLAG_GOTPIC) == 0)
  652:                     addr = bswap32(addr);
  653: #endif
  654:                 addr = calc_reloc(addr, libinfo, id, 0);
  655:                 if (addr == RELOC_FAILED)
  656:                     return -ENOEXEC;
  657: 
  658:                 /* Write back the relocated pointer.  */
  659:                 if (put_user_ual(addr, rp))
  660:                     return -EFAULT;
  661:             }
  662:         }
  663:     } else {
  664:         for (i = 0; i < relocs; i++) {
  665:             abi_ulong relval;
  666:             if (get_user_ual(relval, reloc + i * sizeof(abi_ulong)))
  667:                 return -EFAULT;
  668:             old_reloc(&libinfo[0], relval);
  669:         }
  670:     }
  671: 
  672:     /* zero the BSS.  */
  673:     memset((void *)((unsigned long)datapos + data_len), 0, bss_len);
  674: 
  675:     return 0;
  676: }
  677: 
  678: 
  679: /****************************************************************************/
  680: #ifdef CONFIG_BINFMT_SHARED_FLAT
  681: 
  682: /*
  683:  * Load a shared library into memory.  The library gets its own data
  684:  * segment (including bss) but not argv/argc/environ.
  685:  */
  686: 
  687: static int load_flat_shared_library(int id, struct lib_info *libs)
  688: {
  689: 	struct linux_binprm bprm;
  690: 	int res;
  691: 	char buf[16];
  692: 
  693: 	/* Create the file name */
  694: 	sprintf(buf, "/lib/lib%d.so", id);
  695: 
  696: 	/* Open the file up */
  697: 	bprm.filename = buf;
  698: 	bprm.file = open_exec(bprm.filename);
  699: 	res = PTR_ERR(bprm.file);
  700: 	if (IS_ERR(bprm.file))
  701: 		return res;
  702: 
  703: 	res = prepare_binprm(&bprm);
  704: 
  705: 	if (res <= (unsigned long)-4096)
  706: 		res = load_flat_file(&bprm, libs, id, NULL);
  707: 	if (bprm.file) {
  708: 		allow_write_access(bprm.file);
  709: 		fput(bprm.file);
  710: 		bprm.file = NULL;
  711: 	}
  712: 	return(res);
  713: }
  714: 
  715: #endif /* CONFIG_BINFMT_SHARED_FLAT */
  716: 
  717: int load_flt_binary(struct linux_binprm * bprm, struct target_pt_regs * regs,
  718:                     struct image_info * info)
  719: {
  720:     struct lib_info libinfo[MAX_SHARED_LIBS];
  721:     abi_ulong p = bprm->p;
  722:     abi_ulong stack_len;
  723:     abi_ulong start_addr;
  724:     abi_ulong sp;
  725:     int res;
  726:     int i, j;
  727: 
  728:     memset(libinfo, 0, sizeof(libinfo));
  729:     /*
  730:      * We have to add the size of our arguments to our stack size
  731:      * otherwise it's too easy for users to create stack overflows
  732:      * by passing in a huge argument list.  And yes,  we have to be
  733:      * pedantic and include space for the argv/envp array as it may have
  734:      * a lot of entries.
  735:      */
  736: #define TOP_OF_ARGS (TARGET_PAGE_SIZE * MAX_ARG_PAGES - sizeof(void *))
  737:     stack_len = TOP_OF_ARGS - bprm->p;             /* the strings */
  738:     stack_len += (bprm->argc + 1) * 4; /* the argv array */
  739:     stack_len += (bprm->envc + 1) * 4; /* the envp array */
  740: 
  741: 
  742:     res = load_flat_file(bprm, libinfo, 0, &stack_len);
  743:     if (res > (unsigned long)-4096)
  744:             return res;
  745: 
  746:     /* Update data segment pointers for all libraries */
  747:     for (i=0; i<MAX_SHARED_LIBS; i++) {
  748:         if (libinfo[i].loaded) {
  749:             abi_ulong p;
  750:             p = libinfo[i].start_data;
  751:             for (j=0; j<MAX_SHARED_LIBS; j++) {
  752:                 p -= 4;
  753:                 /* FIXME - handle put_user() failures */
  754:                 if (put_user_ual(libinfo[j].loaded
  755:                                  ? libinfo[j].start_data
  756:                                  : UNLOADED_LIB,
  757:                                  p))
  758:                     return -EFAULT;
  759:             }
  760:         }
  761:     }
  762: 
  763:     p = ((libinfo[0].start_brk + stack_len + 3) & ~3) - 4;
  764:     DBG_FLT("p=%x\n", (int)p);
  765: 
  766:     /* Copy argv/envp.  */
  767:     p = copy_strings(p, bprm->envc, bprm->envp);
  768:     p = copy_strings(p, bprm->argc, bprm->argv);
  769:     /* Align stack.  */
  770:     sp = p & ~(abi_ulong)(sizeof(abi_ulong) - 1);
  771:     /* Enforce final stack alignment of 16 bytes.  This is sufficient
  772:        for all current targets, and excess alignment is harmless.  */
  773:     stack_len = bprm->envc + bprm->argc + 2;
  774:     stack_len += 3;	/* argc, arvg, argp */
  775:     stack_len *= sizeof(abi_ulong);
  776:     if ((sp + stack_len) & 15)
  777:         sp -= 16 - ((sp + stack_len) & 15);
  778:     sp = loader_build_argptr(bprm->envc, bprm->argc, sp, p, 1);
  779: 
  780:     /* Fake some return addresses to ensure the call chain will
  781:      * initialise library in order for us.  We are required to call
  782:      * lib 1 first, then 2, ... and finally the main program (id 0).
  783:      */
  784:     start_addr = libinfo[0].entry;
  785: 
  786: #ifdef CONFIG_BINFMT_SHARED_FLAT
  787: #error here
  788:     for (i = MAX_SHARED_LIBS-1; i>0; i--) {
  789:             if (libinfo[i].loaded) {
  790:                     /* Push previos first to call address */
  791:                     --sp;
  792:                     if (put_user_ual(start_addr, sp))
  793:                         return -EFAULT;
  794:                     start_addr = libinfo[i].entry;
  795:             }
  796:     }
  797: #endif
  798: 
  799:     /* Stash our initial stack pointer into the mm structure */
  800:     info->start_code = libinfo[0].start_code;
  801:     info->end_code = libinfo[0].start_code = libinfo[0].text_len;
  802:     info->start_data = libinfo[0].start_data;
  803:     info->end_data = libinfo[0].end_data;
  804:     info->start_brk = libinfo[0].start_brk;
  805:     info->start_stack = sp;
  806:     info->stack_limit = libinfo[0].start_brk;
  807:     info->entry = start_addr;
  808:     info->code_offset = info->start_code;
  809:     info->data_offset = info->start_data - libinfo[0].text_len;
  810: 
  811:     DBG_FLT("start_thread(entry=0x%x, start_stack=0x%x)\n",
  812:             (int)info->entry, (int)info->start_stack);
  813: 
  814:     return 0;
  815: }

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