1 // SPDX-License-Identifier: GPL-2.0
2 /****************************************************************************/
4 * linux/fs/binfmt_flat.c
6 * Copyright (C) 2000-2003 David McCullough <davidm@snapgear.com>
7 * Copyright (C) 2002 Greg Ungerer <gerg@snapgear.com>
8 * Copyright (C) 2002 SnapGear, by Paul Dale <pauli@snapgear.com>
9 * Copyright (C) 2000, 2001 Lineo, by David McCullough <davidm@lineo.com>
12 * linux/fs/binfmt_aout.c:
13 * Copyright (C) 1991, 1992, 1996 Linus Torvalds
14 * linux/fs/binfmt_flat.c for 2.0 kernel
15 * Copyright (C) 1998 Kenneth Albanowski <kjahds@kjahds.com>
16 * JAN/99 -- coded full program relocation (gerg@snapgear.com)
19 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
21 #include <linux/kernel.h>
22 #include <linux/sched.h>
23 #include <linux/sched/task_stack.h>
25 #include <linux/mman.h>
26 #include <linux/errno.h>
27 #include <linux/signal.h>
28 #include <linux/string.h>
30 #include <linux/file.h>
31 #include <linux/ptrace.h>
32 #include <linux/user.h>
33 #include <linux/slab.h>
34 #include <linux/binfmts.h>
35 #include <linux/personality.h>
36 #include <linux/init.h>
37 #include <linux/flat.h>
38 #include <linux/uaccess.h>
39 #include <linux/vmalloc.h>
41 #include <asm/byteorder.h>
42 #include <asm/unaligned.h>
43 #include <asm/cacheflush.h>
47 #ifndef flat_get_relocate_addr
48 #define flat_get_relocate_addr(rel) (rel)
51 /****************************************************************************/
54 * User data (data section and bss) needs to be aligned.
55 * We pick 0x20 here because it is the max value elf2flt has always
56 * used in producing FLAT files, and because it seems to be large
57 * enough to make all the gcc alignment related tests happy.
59 #define FLAT_DATA_ALIGN (0x20)
62 * User data (stack) also needs to be aligned.
63 * Here we can be a bit looser than the data sections since this
64 * needs to only meet arch ABI requirements.
66 #define FLAT_STACK_ALIGN max_t(unsigned long, sizeof(void *), ARCH_SLAB_MINALIGN)
68 #define RELOC_FAILED 0xff00ff01 /* Relocation incorrect somewhere */
69 #define UNLOADED_LIB 0x7ff000ff /* Placeholder for unused library */
71 #ifdef CONFIG_BINFMT_SHARED_FLAT
72 #define MAX_SHARED_LIBS (4)
74 #define MAX_SHARED_LIBS (1)
77 #ifdef CONFIG_BINFMT_FLAT_NO_DATA_START_OFFSET
78 #define DATA_START_OFFSET_WORDS (0)
80 #define DATA_START_OFFSET_WORDS (MAX_SHARED_LIBS)
85 unsigned long start_code; /* Start of text segment */
86 unsigned long start_data; /* Start of data segment */
87 unsigned long start_brk; /* End of data segment */
88 unsigned long text_len; /* Length of text segment */
89 unsigned long entry; /* Start address for this module */
90 unsigned long build_date; /* When this one was compiled */
91 bool loaded; /* Has this library been loaded? */
92 } lib_list[MAX_SHARED_LIBS];
95 #ifdef CONFIG_BINFMT_SHARED_FLAT
96 static int load_flat_shared_library(int id, struct lib_info *p);
99 static int load_flat_binary(struct linux_binprm *);
100 static int flat_core_dump(struct coredump_params *cprm);
102 static struct linux_binfmt flat_format = {
103 .module = THIS_MODULE,
104 .load_binary = load_flat_binary,
105 .core_dump = flat_core_dump,
106 .min_coredump = PAGE_SIZE
109 /****************************************************************************/
111 * Routine writes a core dump image in the current directory.
112 * Currently only a stub-function.
115 static int flat_core_dump(struct coredump_params *cprm)
117 pr_warn("Process %s:%d received signr %d and should have core dumped\n",
118 current->comm, current->pid, cprm->siginfo->si_signo);
122 /****************************************************************************/
124 * create_flat_tables() parses the env- and arg-strings in new user
125 * memory and creates the pointer tables from them, and puts their
126 * addresses on the "stack", recording the new stack pointer value.
129 static int create_flat_tables(struct linux_binprm *bprm, unsigned long arg_start)
132 unsigned long __user *sp;
135 p = (char __user *)arg_start;
136 sp = (unsigned long __user *)current->mm->start_stack;
138 sp -= bprm->envc + 1;
139 sp -= bprm->argc + 1;
140 if (IS_ENABLED(CONFIG_BINFMT_FLAT_ARGVP_ENVP_ON_STACK))
141 sp -= 2; /* argvp + envp */
144 current->mm->start_stack = (unsigned long)sp & -FLAT_STACK_ALIGN;
145 sp = (unsigned long __user *)current->mm->start_stack;
147 if (put_user(bprm->argc, sp++))
149 if (IS_ENABLED(CONFIG_BINFMT_FLAT_ARGVP_ENVP_ON_STACK)) {
150 unsigned long argv, envp;
151 argv = (unsigned long)(sp + 2);
152 envp = (unsigned long)(sp + 2 + bprm->argc + 1);
153 if (put_user(argv, sp++) || put_user(envp, sp++))
157 current->mm->arg_start = (unsigned long)p;
158 for (i = bprm->argc; i > 0; i--) {
159 if (put_user((unsigned long)p, sp++))
161 len = strnlen_user(p, MAX_ARG_STRLEN);
162 if (!len || len > MAX_ARG_STRLEN)
166 if (put_user(0, sp++))
168 current->mm->arg_end = (unsigned long)p;
170 current->mm->env_start = (unsigned long) p;
171 for (i = bprm->envc; i > 0; i--) {
172 if (put_user((unsigned long)p, sp++))
174 len = strnlen_user(p, MAX_ARG_STRLEN);
175 if (!len || len > MAX_ARG_STRLEN)
179 if (put_user(0, sp++))
181 current->mm->env_end = (unsigned long)p;
186 /****************************************************************************/
188 #ifdef CONFIG_BINFMT_ZFLAT
190 #include <linux/zlib.h>
192 #define LBUFSIZE 4000
195 #define ASCII_FLAG 0x01 /* bit 0 set: file probably ASCII text */
196 #define CONTINUATION 0x02 /* bit 1 set: continuation of multi-part gzip file */
197 #define EXTRA_FIELD 0x04 /* bit 2 set: extra field present */
198 #define ORIG_NAME 0x08 /* bit 3 set: original file name present */
199 #define COMMENT 0x10 /* bit 4 set: file comment present */
200 #define ENCRYPTED 0x20 /* bit 5 set: file is encrypted */
201 #define RESERVED 0xC0 /* bit 6,7: reserved */
203 static int decompress_exec(struct linux_binprm *bprm, loff_t fpos, char *dst,
210 pr_debug("decompress_exec(offset=%llx,buf=%p,len=%lx)\n", fpos, dst, len);
212 memset(&strm, 0, sizeof(strm));
213 strm.workspace = kmalloc(zlib_inflate_workspacesize(), GFP_KERNEL);
217 buf = kmalloc(LBUFSIZE, GFP_KERNEL);
223 /* Read in first chunk of data and parse gzip header. */
224 ret = kernel_read(bprm->file, buf, LBUFSIZE, &fpos);
232 /* Check minimum size -- gzip header */
234 pr_debug("file too small?\n");
238 /* Check gzip magic number */
239 if ((buf[0] != 037) || ((buf[1] != 0213) && (buf[1] != 0236))) {
240 pr_debug("unknown compression magic?\n");
244 /* Check gzip method */
246 pr_debug("unknown compression method?\n");
249 /* Check gzip flags */
250 if ((buf[3] & ENCRYPTED) || (buf[3] & CONTINUATION) ||
251 (buf[3] & RESERVED)) {
252 pr_debug("unknown flags?\n");
257 if (buf[3] & EXTRA_FIELD) {
258 ret += 2 + buf[10] + (buf[11] << 8);
259 if (unlikely(ret >= LBUFSIZE)) {
260 pr_debug("buffer overflow (EXTRA)?\n");
264 if (buf[3] & ORIG_NAME) {
265 while (ret < LBUFSIZE && buf[ret++] != 0)
267 if (unlikely(ret == LBUFSIZE)) {
268 pr_debug("buffer overflow (ORIG_NAME)?\n");
272 if (buf[3] & COMMENT) {
273 while (ret < LBUFSIZE && buf[ret++] != 0)
275 if (unlikely(ret == LBUFSIZE)) {
276 pr_debug("buffer overflow (COMMENT)?\n");
282 strm.avail_in -= ret;
285 strm.avail_out = len;
288 if (zlib_inflateInit2(&strm, -MAX_WBITS) != Z_OK) {
289 pr_debug("zlib init failed?\n");
293 while ((ret = zlib_inflate(&strm, Z_NO_FLUSH)) == Z_OK) {
294 ret = kernel_read(bprm->file, buf, LBUFSIZE, &fpos);
305 pr_debug("decompression failed (%d), %s\n",
312 zlib_inflateEnd(&strm);
316 kfree(strm.workspace);
320 #endif /* CONFIG_BINFMT_ZFLAT */
322 /****************************************************************************/
325 calc_reloc(unsigned long r, struct lib_info *p, int curid, int internalp)
329 unsigned long start_brk;
330 unsigned long start_data;
331 unsigned long text_len;
332 unsigned long start_code;
334 #ifdef CONFIG_BINFMT_SHARED_FLAT
336 id = curid; /* Relocs of 0 are always self referring */
338 id = (r >> 24) & 0xff; /* Find ID for this reloc */
339 r &= 0x00ffffff; /* Trim ID off here */
341 if (id >= MAX_SHARED_LIBS) {
342 pr_err("reference 0x%lx to shared library %d", r, id);
347 pr_err("reloc address 0x%lx not in same module "
348 "(%d != %d)", r, curid, id);
350 } else if (!p->lib_list[id].loaded &&
351 load_flat_shared_library(id, p) < 0) {
352 pr_err("failed to load library %d", id);
355 /* Check versioning information (i.e. time stamps) */
356 if (p->lib_list[id].build_date && p->lib_list[curid].build_date &&
357 p->lib_list[curid].build_date < p->lib_list[id].build_date) {
358 pr_err("library %d is younger than %d", id, curid);
366 start_brk = p->lib_list[id].start_brk;
367 start_data = p->lib_list[id].start_data;
368 start_code = p->lib_list[id].start_code;
369 text_len = p->lib_list[id].text_len;
371 if (r > start_brk - start_data + text_len) {
372 pr_err("reloc outside program 0x%lx (0 - 0x%lx/0x%lx)",
373 r, start_brk-start_data+text_len, text_len);
377 if (r < text_len) /* In text segment */
378 addr = r + start_code;
379 else /* In data segment */
380 addr = r - text_len + start_data;
382 /* Range checked already above so doing the range tests is redundant...*/
386 pr_cont(", killing %s!\n", current->comm);
387 send_sig(SIGSEGV, current, 0);
392 /****************************************************************************/
394 #ifdef CONFIG_BINFMT_FLAT_OLD
395 static void old_reloc(unsigned long rl)
397 static const char *segment[] = { "TEXT", "DATA", "BSS", "*UNKNOWN*" };
399 unsigned long __user *ptr;
403 #if defined(CONFIG_COLDFIRE)
404 ptr = (unsigned long __user *)(current->mm->start_code + r.reloc.offset);
406 ptr = (unsigned long __user *)(current->mm->start_data + r.reloc.offset);
410 pr_debug("Relocation of variable at DATASEG+%x "
411 "(address %p, currently %lx) into segment %s\n",
412 r.reloc.offset, ptr, val, segment[r.reloc.type]);
414 switch (r.reloc.type) {
415 case OLD_FLAT_RELOC_TYPE_TEXT:
416 val += current->mm->start_code;
418 case OLD_FLAT_RELOC_TYPE_DATA:
419 val += current->mm->start_data;
421 case OLD_FLAT_RELOC_TYPE_BSS:
422 val += current->mm->end_data;
425 pr_err("Unknown relocation type=%x\n", r.reloc.type);
430 pr_debug("Relocation became %lx\n", val);
432 #endif /* CONFIG_BINFMT_FLAT_OLD */
434 /****************************************************************************/
436 static int load_flat_file(struct linux_binprm *bprm,
437 struct lib_info *libinfo, int id, unsigned long *extra_stack)
439 struct flat_hdr *hdr;
440 unsigned long textpos, datapos, realdatastart;
441 u32 text_len, data_len, bss_len, stack_len, full_data, flags;
442 unsigned long len, memp, memp_size, extra, rlim;
443 __be32 __user *reloc;
447 unsigned long start_code, end_code;
451 hdr = ((struct flat_hdr *) bprm->buf); /* exec-header */
453 text_len = ntohl(hdr->data_start);
454 data_len = ntohl(hdr->data_end) - ntohl(hdr->data_start);
455 bss_len = ntohl(hdr->bss_end) - ntohl(hdr->data_end);
456 stack_len = ntohl(hdr->stack_size);
458 stack_len += *extra_stack;
459 *extra_stack = stack_len;
461 relocs = ntohl(hdr->reloc_count);
462 flags = ntohl(hdr->flags);
463 rev = ntohl(hdr->rev);
464 full_data = data_len + relocs * sizeof(unsigned long);
466 if (strncmp(hdr->magic, "bFLT", 4)) {
468 * Previously, here was a printk to tell people
469 * "BINFMT_FLAT: bad header magic".
470 * But for the kernel which also use ELF FD-PIC format, this
471 * error message is confusing.
472 * because a lot of people do not manage to produce good
478 if (flags & FLAT_FLAG_KTRACE)
479 pr_info("Loading file: %s\n", bprm->filename);
481 #ifdef CONFIG_BINFMT_FLAT_OLD
482 if (rev != FLAT_VERSION && rev != OLD_FLAT_VERSION) {
483 pr_err("bad flat file version 0x%x (supported 0x%lx and 0x%lx)\n",
484 rev, FLAT_VERSION, OLD_FLAT_VERSION);
489 /* Don't allow old format executables to use shared libraries */
490 if (rev == OLD_FLAT_VERSION && id != 0) {
491 pr_err("shared libraries are not available before rev 0x%lx\n",
498 * fix up the flags for the older format, there were all kinds
499 * of endian hacks, this only works for the simple cases
501 if (rev == OLD_FLAT_VERSION &&
502 (flags || IS_ENABLED(CONFIG_BINFMT_FLAT_OLD_ALWAYS_RAM)))
503 flags = FLAT_FLAG_RAM;
505 #else /* CONFIG_BINFMT_FLAT_OLD */
506 if (rev != FLAT_VERSION) {
507 pr_err("bad flat file version 0x%x (supported 0x%lx)\n",
512 #endif /* !CONFIG_BINFMT_FLAT_OLD */
515 * Make sure the header params are sane.
516 * 28 bits (256 MB) is way more than reasonable in this case.
517 * If some top bits are set we have probable binary corruption.
519 if ((text_len | data_len | bss_len | stack_len | full_data) >> 28) {
520 pr_err("bad header\n");
525 #ifndef CONFIG_BINFMT_ZFLAT
526 if (flags & (FLAT_FLAG_GZIP|FLAT_FLAG_GZDATA)) {
527 pr_err("Support for ZFLAT executables is not enabled.\n");
534 * Check initial limits. This avoids letting people circumvent
535 * size limits imposed on them by creating programs with large
536 * arrays in the data or bss.
538 rlim = rlimit(RLIMIT_DATA);
539 if (rlim >= RLIM_INFINITY)
541 if (data_len + bss_len > rlim) {
546 /* Flush all traces of the currently running executable */
548 ret = begin_new_exec(bprm);
552 /* OK, This is the point of no return */
553 set_personality(PER_LINUX_32BIT);
554 setup_new_exec(bprm);
558 * calculate the extra space we need to map in
560 extra = max_t(unsigned long, bss_len + stack_len,
561 relocs * sizeof(unsigned long));
564 * there are a couple of cases here, the separate code/data
565 * case, and then the fully copied to RAM case which lumps
568 if (!IS_ENABLED(CONFIG_MMU) && !(flags & (FLAT_FLAG_RAM|FLAT_FLAG_GZIP))) {
570 * this should give us a ROM ptr, but if it doesn't we don't
573 pr_debug("ROM mapping of file (we hope)\n");
575 textpos = vm_mmap(bprm->file, 0, text_len, PROT_READ|PROT_EXEC,
577 if (!textpos || IS_ERR_VALUE(textpos)) {
581 pr_err("Unable to mmap process text, errno %d\n", ret);
585 len = data_len + extra +
586 DATA_START_OFFSET_WORDS * sizeof(unsigned long);
587 len = PAGE_ALIGN(len);
588 realdatastart = vm_mmap(NULL, 0, len,
589 PROT_READ|PROT_WRITE|PROT_EXEC, MAP_PRIVATE, 0);
591 if (realdatastart == 0 || IS_ERR_VALUE(realdatastart)) {
595 pr_err("Unable to allocate RAM for process data, "
597 vm_munmap(textpos, text_len);
600 datapos = ALIGN(realdatastart +
601 DATA_START_OFFSET_WORDS * sizeof(unsigned long),
604 pr_debug("Allocated data+bss+stack (%u bytes): %lx\n",
605 data_len + bss_len + stack_len, datapos);
607 fpos = ntohl(hdr->data_start);
608 #ifdef CONFIG_BINFMT_ZFLAT
609 if (flags & FLAT_FLAG_GZDATA) {
610 result = decompress_exec(bprm, fpos, (char *)datapos,
615 result = read_code(bprm->file, datapos, fpos,
618 if (IS_ERR_VALUE(result)) {
620 pr_err("Unable to read data+bss, errno %d\n", ret);
621 vm_munmap(textpos, text_len);
622 vm_munmap(realdatastart, len);
626 reloc = (__be32 __user *)
627 (datapos + (ntohl(hdr->reloc_start) - text_len));
628 memp = realdatastart;
632 len = text_len + data_len + extra +
633 DATA_START_OFFSET_WORDS * sizeof(u32);
634 len = PAGE_ALIGN(len);
635 textpos = vm_mmap(NULL, 0, len,
636 PROT_READ | PROT_EXEC | PROT_WRITE, MAP_PRIVATE, 0);
638 if (!textpos || IS_ERR_VALUE(textpos)) {
642 pr_err("Unable to allocate RAM for process text/data, "
647 realdatastart = textpos + ntohl(hdr->data_start);
648 datapos = ALIGN(realdatastart +
649 DATA_START_OFFSET_WORDS * sizeof(u32),
652 reloc = (__be32 __user *)
653 (datapos + (ntohl(hdr->reloc_start) - text_len));
656 #ifdef CONFIG_BINFMT_ZFLAT
658 * load it all in and treat it like a RAM load from now on
660 if (flags & FLAT_FLAG_GZIP) {
662 result = decompress_exec(bprm, sizeof(struct flat_hdr),
663 (((char *)textpos) + sizeof(struct flat_hdr)),
664 (text_len + full_data
665 - sizeof(struct flat_hdr)),
667 memmove((void *) datapos, (void *) realdatastart,
671 * This is used on MMU systems mainly for testing.
672 * Let's use a kernel buffer to simplify things.
674 long unz_text_len = text_len - sizeof(struct flat_hdr);
675 long unz_len = unz_text_len + full_data;
676 char *unz_data = vmalloc(unz_len);
680 result = decompress_exec(bprm, sizeof(struct flat_hdr),
681 unz_data, unz_len, 0);
683 (copy_to_user((void __user *)textpos + sizeof(struct flat_hdr),
684 unz_data, unz_text_len) ||
685 copy_to_user((void __user *)datapos,
686 unz_data + unz_text_len, full_data)))
691 } else if (flags & FLAT_FLAG_GZDATA) {
692 result = read_code(bprm->file, textpos, 0, text_len);
693 if (!IS_ERR_VALUE(result)) {
695 result = decompress_exec(bprm, text_len, (char *) datapos,
698 char *unz_data = vmalloc(full_data);
702 result = decompress_exec(bprm, text_len,
703 unz_data, full_data, 0);
705 copy_to_user((void __user *)datapos,
706 unz_data, full_data))
713 #endif /* CONFIG_BINFMT_ZFLAT */
715 result = read_code(bprm->file, textpos, 0, text_len);
716 if (!IS_ERR_VALUE(result))
717 result = read_code(bprm->file, datapos,
718 ntohl(hdr->data_start),
721 if (IS_ERR_VALUE(result)) {
723 pr_err("Unable to read code+data+bss, errno %d\n", ret);
724 vm_munmap(textpos, text_len + data_len + extra +
725 DATA_START_OFFSET_WORDS * sizeof(u32));
730 start_code = textpos + sizeof(struct flat_hdr);
731 end_code = textpos + text_len;
732 text_len -= sizeof(struct flat_hdr); /* the real code len */
734 /* The main program needs a little extra setup in the task structure */
736 current->mm->start_code = start_code;
737 current->mm->end_code = end_code;
738 current->mm->start_data = datapos;
739 current->mm->end_data = datapos + data_len;
741 * set up the brk stuff, uses any slack left in data/bss/stack
742 * allocation. We put the brk after the bss (between the bss
743 * and stack) like other platforms.
744 * Userspace code relies on the stack pointer starting out at
745 * an address right at the end of a page.
747 current->mm->start_brk = datapos + data_len + bss_len;
748 current->mm->brk = (current->mm->start_brk + 3) & ~3;
750 current->mm->context.end_brk = memp + memp_size - stack_len;
754 if (flags & FLAT_FLAG_KTRACE) {
755 pr_info("Mapping is %lx, Entry point is %x, data_start is %x\n",
756 textpos, 0x00ffffff&ntohl(hdr->entry), ntohl(hdr->data_start));
757 pr_info("%s %s: TEXT=%lx-%lx DATA=%lx-%lx BSS=%lx-%lx\n",
758 id ? "Lib" : "Load", bprm->filename,
759 start_code, end_code, datapos, datapos + data_len,
760 datapos + data_len, (datapos + data_len + bss_len + 3) & ~3);
763 /* Store the current module values into the global library structure */
764 libinfo->lib_list[id].start_code = start_code;
765 libinfo->lib_list[id].start_data = datapos;
766 libinfo->lib_list[id].start_brk = datapos + data_len + bss_len;
767 libinfo->lib_list[id].text_len = text_len;
768 libinfo->lib_list[id].loaded = 1;
769 libinfo->lib_list[id].entry = (0x00ffffff & ntohl(hdr->entry)) + textpos;
770 libinfo->lib_list[id].build_date = ntohl(hdr->build_date);
773 * We just load the allocations into some temporary memory to
774 * help simplify all this mumbo jumbo
776 * We've got two different sections of relocation entries.
777 * The first is the GOT which resides at the beginning of the data segment
778 * and is terminated with a -1. This one can be relocated in place.
779 * The second is the extra relocation entries tacked after the image's
780 * data segment. These require a little more processing as the entry is
781 * really an offset into the image which contains an offset into the
784 if (flags & FLAT_FLAG_GOTPIC) {
785 for (rp = (u32 __user *)datapos; ; rp++) {
787 if (get_user(rp_val, rp))
789 if (rp_val == 0xffffffff)
792 addr = calc_reloc(rp_val, libinfo, id, 0);
793 if (addr == RELOC_FAILED) {
797 if (put_user(addr, rp))
804 * Now run through the relocation entries.
805 * We've got to be careful here as C++ produces relocatable zero
806 * entries in the constructor and destructor tables which are then
807 * tested for being not zero (which will always occur unless we're
808 * based from address zero). This causes an endless loop as __start
809 * is at zero. The solution used is to not relocate zero addresses.
810 * This has the negative side effect of not allowing a global data
811 * reference to be statically initialised to _stext (I've moved
812 * __start to address 4 so that is okay).
814 if (rev > OLD_FLAT_VERSION) {
815 for (i = 0; i < relocs; i++) {
820 * Get the address of the pointer to be
821 * relocated (of course, the address has to be
824 if (get_user(tmp, reloc + i))
827 addr = flat_get_relocate_addr(relval);
828 rp = (u32 __user *)calc_reloc(addr, libinfo, id, 1);
829 if (rp == (u32 __user *)RELOC_FAILED) {
834 /* Get the pointer's value. */
835 ret = flat_get_addr_from_rp(rp, relval, flags, &addr);
841 * Do the relocation. PIC relocs in the data section are
842 * already in target order
844 if ((flags & FLAT_FLAG_GOTPIC) == 0) {
846 * Meh, the same value can have a different
847 * byte order based on a flag..
849 addr = ntohl((__force __be32)addr);
851 addr = calc_reloc(addr, libinfo, id, 0);
852 if (addr == RELOC_FAILED) {
857 /* Write back the relocated pointer. */
858 ret = flat_put_addr_at_rp(rp, addr, relval);
863 #ifdef CONFIG_BINFMT_FLAT_OLD
865 for (i = 0; i < relocs; i++) {
867 if (get_user(relval, reloc + i))
869 old_reloc(ntohl(relval));
871 #endif /* CONFIG_BINFMT_FLAT_OLD */
874 flush_icache_user_range(start_code, end_code);
876 /* zero the BSS, BRK and stack areas */
877 if (clear_user((void __user *)(datapos + data_len), bss_len +
878 (memp + memp_size - stack_len - /* end brk */
879 libinfo->lib_list[id].start_brk) + /* start brk */
889 /****************************************************************************/
890 #ifdef CONFIG_BINFMT_SHARED_FLAT
893 * Load a shared library into memory. The library gets its own data
894 * segment (including bss) but not argv/argc/environ.
897 static int load_flat_shared_library(int id, struct lib_info *libs)
900 * This is a fake bprm struct; only the members "buf", "file" and
901 * "filename" are actually used.
903 struct linux_binprm bprm;
908 memset(&bprm, 0, sizeof(bprm));
910 /* Create the file name */
911 sprintf(buf, "/lib/lib%d.so", id);
913 /* Open the file up */
915 bprm.file = open_exec(bprm.filename);
916 res = PTR_ERR(bprm.file);
917 if (IS_ERR(bprm.file))
920 res = kernel_read(bprm.file, bprm.buf, BINPRM_BUF_SIZE, &pos);
923 res = load_flat_file(&bprm, libs, id, NULL);
925 allow_write_access(bprm.file);
931 #endif /* CONFIG_BINFMT_SHARED_FLAT */
932 /****************************************************************************/
935 * These are the functions used to load flat style executables and shared
936 * libraries. There is no binary dependent code anywhere else.
939 static int load_flat_binary(struct linux_binprm *bprm)
941 struct lib_info libinfo;
942 struct pt_regs *regs = current_pt_regs();
943 unsigned long stack_len = 0;
944 unsigned long start_addr;
948 memset(&libinfo, 0, sizeof(libinfo));
951 * We have to add the size of our arguments to our stack size
952 * otherwise it's too easy for users to create stack overflows
953 * by passing in a huge argument list. And yes, we have to be
954 * pedantic and include space for the argv/envp array as it may have
958 stack_len += PAGE_SIZE * MAX_ARG_PAGES - bprm->p; /* the strings */
960 stack_len += (bprm->argc + 1) * sizeof(char *); /* the argv array */
961 stack_len += (bprm->envc + 1) * sizeof(char *); /* the envp array */
962 stack_len = ALIGN(stack_len, FLAT_STACK_ALIGN);
964 res = load_flat_file(bprm, &libinfo, 0, &stack_len);
968 /* Update data segment pointers for all libraries */
969 for (i = 0; i < MAX_SHARED_LIBS; i++) {
970 if (!libinfo.lib_list[i].loaded)
972 for (j = 0; j < MAX_SHARED_LIBS; j++) {
973 unsigned long val = libinfo.lib_list[j].loaded ?
974 libinfo.lib_list[j].start_data : UNLOADED_LIB;
975 unsigned long __user *p = (unsigned long __user *)
976 libinfo.lib_list[i].start_data;
978 if (put_user(val, p))
983 set_binfmt(&flat_format);
986 res = setup_arg_pages(bprm, STACK_TOP, EXSTACK_DEFAULT);
988 res = create_flat_tables(bprm, bprm->p);
990 /* Stash our initial stack pointer into the mm structure */
991 current->mm->start_stack =
992 ((current->mm->context.end_brk + stack_len + 3) & ~3) - 4;
993 pr_debug("sp=%lx\n", current->mm->start_stack);
995 /* copy the arg pages onto the stack */
996 res = transfer_args_to_stack(bprm, ¤t->mm->start_stack);
998 res = create_flat_tables(bprm, current->mm->start_stack);
1003 /* Fake some return addresses to ensure the call chain will
1004 * initialise library in order for us. We are required to call
1005 * lib 1 first, then 2, ... and finally the main program (id 0).
1007 start_addr = libinfo.lib_list[0].entry;
1009 #ifdef CONFIG_BINFMT_SHARED_FLAT
1010 for (i = MAX_SHARED_LIBS-1; i > 0; i--) {
1011 if (libinfo.lib_list[i].loaded) {
1012 /* Push previos first to call address */
1013 unsigned long __user *sp;
1014 current->mm->start_stack -= sizeof(unsigned long);
1015 sp = (unsigned long __user *)current->mm->start_stack;
1016 if (put_user(start_addr, sp))
1018 start_addr = libinfo.lib_list[i].entry;
1023 #ifdef FLAT_PLAT_INIT
1024 FLAT_PLAT_INIT(regs);
1027 finalize_exec(bprm);
1028 pr_debug("start_thread(regs=0x%p, entry=0x%lx, start_stack=0x%lx)\n",
1029 regs, start_addr, current->mm->start_stack);
1030 start_thread(regs, start_addr, current->mm->start_stack);
1035 /****************************************************************************/
1037 static int __init init_flat_binfmt(void)
1039 register_binfmt(&flat_format);
1042 core_initcall(init_flat_binfmt);
1044 /****************************************************************************/