--- /dev/null
+/****************************************************************************/
+/*
+ * linux/fs/binfmt_flat.c
+ *
+ * Copyright (C) 2000-2003 David McCullough <davidm@snapgear.com>
+ * Copyright (C) 2002 Greg Ungerer <gerg@snapgear.com>
+ * Copyright (C) 2002 SnapGear, by Paul Dale <pauli@snapgear.com>
+ * Copyright (C) 2000, 2001 Lineo, by David McCullough <davidm@lineo.com>
+ * based heavily on:
+ *
+ * linux/fs/binfmt_aout.c:
+ * Copyright (C) 1991, 1992, 1996 Linus Torvalds
+ * linux/fs/binfmt_flat.c for 2.0 kernel
+ * Copyright (C) 1998 Kenneth Albanowski <kjahds@kjahds.com>
+ * JAN/99 -- coded full program relocation (gerg@snapgear.com)
+ */
+
+#include <linux/export.h>
+#include <linux/kernel.h>
+#include <linux/sched.h>
+#include <linux/mm.h>
+#include <linux/mman.h>
+#include <linux/errno.h>
+#include <linux/signal.h>
+#include <linux/string.h>
+#include <linux/fs.h>
+#include <linux/file.h>
+#include <linux/stat.h>
+#include <linux/fcntl.h>
+#include <linux/ptrace.h>
+#include <linux/user.h>
+#include <linux/slab.h>
+#include <linux/binfmts.h>
+#include <linux/personality.h>
+#include <linux/init.h>
+#include <linux/flat.h>
+#include <linux/syscalls.h>
+
+#include <asm/byteorder.h>
+#include <asm/uaccess.h>
+#include <asm/unaligned.h>
+#include <asm/cacheflush.h>
+#include <asm/page.h>
+
+/****************************************************************************/
+
+#if 0
+#define DEBUG 1
+#endif
+
+#ifdef DEBUG
+#define DBG_FLT(a...) printk(a)
+#else
+#define DBG_FLT(a...)
+#endif
+
+/*
+ * User data (data section and bss) needs to be aligned.
+ * We pick 0x20 here because it is the max value elf2flt has always
+ * used in producing FLAT files, and because it seems to be large
+ * enough to make all the gcc alignment related tests happy.
+ */
+#define FLAT_DATA_ALIGN (0x20)
+
+/*
+ * User data (stack) also needs to be aligned.
+ * Here we can be a bit looser than the data sections since this
+ * needs to only meet arch ABI requirements.
+ */
+#define FLAT_STACK_ALIGN max_t(unsigned long, sizeof(void *), ARCH_SLAB_MINALIGN)
+
+#define RELOC_FAILED 0xff00ff01 /* Relocation incorrect somewhere */
+#define UNLOADED_LIB 0x7ff000ff /* Placeholder for unused library */
+
+struct lib_info {
+ struct {
+ unsigned long start_code; /* Start of text segment */
+ unsigned long start_data; /* Start of data segment */
+ unsigned long start_brk; /* End of data segment */
+ unsigned long text_len; /* Length of text segment */
+ unsigned long entry; /* Start address for this module */
+ unsigned long build_date; /* When this one was compiled */
+ short loaded; /* Has this library been loaded? */
+ } lib_list[MAX_SHARED_LIBS];
+};
+
+#ifdef CONFIG_BINFMT_SHARED_FLAT
+static int load_flat_shared_library(int id, struct lib_info *p);
+#endif
+
+static int load_flat_binary(struct linux_binprm *);
+static int flat_core_dump(struct coredump_params *cprm);
+
+static struct linux_binfmt flat_format = {
+ .module = THIS_MODULE,
+ .load_binary = load_flat_binary,
+ .core_dump = flat_core_dump,
+ .min_coredump = PAGE_SIZE
+};
+
+/****************************************************************************/
+/*
+ * Routine writes a core dump image in the current directory.
+ * Currently only a stub-function.
+ */
+
+static int flat_core_dump(struct coredump_params *cprm)
+{
+ printk("Process %s:%d received signr %d and should have core dumped\n",
+ current->comm, current->pid, (int) cprm->siginfo->si_signo);
+ return(1);
+}
+
+/****************************************************************************/
+/*
+ * create_flat_tables() parses the env- and arg-strings in new user
+ * memory and creates the pointer tables from them, and puts their
+ * addresses on the "stack", returning the new stack pointer value.
+ */
+
+static unsigned long create_flat_tables(
+ unsigned long pp,
+ struct linux_binprm * bprm)
+{
+ unsigned long *argv,*envp;
+ unsigned long * sp;
+ char * p = (char*)pp;
+ int argc = bprm->argc;
+ int envc = bprm->envc;
+ char uninitialized_var(dummy);
+
+ sp = (unsigned long *)p;
+ sp -= (envc + argc + 2) + 1 + (flat_argvp_envp_on_stack() ? 2 : 0);
+ sp = (unsigned long *) ((unsigned long)sp & -FLAT_STACK_ALIGN);
+ argv = sp + 1 + (flat_argvp_envp_on_stack() ? 2 : 0);
+ envp = argv + (argc + 1);
+
+ if (flat_argvp_envp_on_stack()) {
+ put_user((unsigned long) envp, sp + 2);
+ put_user((unsigned long) argv, sp + 1);
+ }
+
+ put_user(argc, sp);
+ current->mm->arg_start = (unsigned long) p;
+ while (argc-->0) {
+ put_user((unsigned long) p, argv++);
+ do {
+ get_user(dummy, p); p++;
+ } while (dummy);
+ }
+ put_user((unsigned long) NULL, argv);
+ current->mm->arg_end = current->mm->env_start = (unsigned long) p;
+ while (envc-->0) {
+ put_user((unsigned long)p, envp); envp++;
+ do {
+ get_user(dummy, p); p++;
+ } while (dummy);
+ }
+ put_user((unsigned long) NULL, envp);
+ current->mm->env_end = (unsigned long) p;
+ return (unsigned long)sp;
+}
+
+/****************************************************************************/
+
+#ifdef CONFIG_BINFMT_ZFLAT
+
+#include <linux/zlib.h>
+
+#define LBUFSIZE 4000
+
+/* gzip flag byte */
+#define ASCII_FLAG 0x01 /* bit 0 set: file probably ASCII text */
+#define CONTINUATION 0x02 /* bit 1 set: continuation of multi-part gzip file */
+#define EXTRA_FIELD 0x04 /* bit 2 set: extra field present */
+#define ORIG_NAME 0x08 /* bit 3 set: original file name present */
+#define COMMENT 0x10 /* bit 4 set: file comment present */
+#define ENCRYPTED 0x20 /* bit 5 set: file is encrypted */
+#define RESERVED 0xC0 /* bit 6,7: reserved */
+
+static int decompress_exec(
+ struct linux_binprm *bprm,
+ unsigned long offset,
+ char *dst,
+ long len,
+ int fd)
+{
+ unsigned char *buf;
+ z_stream strm;
+ loff_t fpos;
+ int ret, retval;
+
+ DBG_FLT("decompress_exec(offset=%x,buf=%x,len=%x)\n",(int)offset, (int)dst, (int)len);
+
+ memset(&strm, 0, sizeof(strm));
+ strm.workspace = kmalloc(zlib_inflate_workspacesize(), GFP_KERNEL);
+ if (strm.workspace == NULL) {
+ DBG_FLT("binfmt_flat: no memory for decompress workspace\n");
+ return -ENOMEM;
+ }
+ buf = kmalloc(LBUFSIZE, GFP_KERNEL);
+ if (buf == NULL) {
+ DBG_FLT("binfmt_flat: no memory for read buffer\n");
+ retval = -ENOMEM;
+ goto out_free;
+ }
+
+ /* Read in first chunk of data and parse gzip header. */
+ fpos = offset;
+ ret = kernel_read(bprm->file, offset, buf, LBUFSIZE);
+
+ strm.next_in = buf;
+ strm.avail_in = ret;
+ strm.total_in = 0;
+ fpos += ret;
+
+ retval = -ENOEXEC;
+
+ /* Check minimum size -- gzip header */
+ if (ret < 10) {
+ DBG_FLT("binfmt_flat: file too small?\n");
+ goto out_free_buf;
+ }
+
+ /* Check gzip magic number */
+ if ((buf[0] != 037) || ((buf[1] != 0213) && (buf[1] != 0236))) {
+ DBG_FLT("binfmt_flat: unknown compression magic?\n");
+ goto out_free_buf;
+ }
+
+ /* Check gzip method */
+ if (buf[2] != 8) {
+ DBG_FLT("binfmt_flat: unknown compression method?\n");
+ goto out_free_buf;
+ }
+ /* Check gzip flags */
+ if ((buf[3] & ENCRYPTED) || (buf[3] & CONTINUATION) ||
+ (buf[3] & RESERVED)) {
+ DBG_FLT("binfmt_flat: unknown flags?\n");
+ goto out_free_buf;
+ }
+
+ ret = 10;
+ if (buf[3] & EXTRA_FIELD) {
+ ret += 2 + buf[10] + (buf[11] << 8);
+ if (unlikely(LBUFSIZE <= ret)) {
+ DBG_FLT("binfmt_flat: buffer overflow (EXTRA)?\n");
+ goto out_free_buf;
+ }
+ }
+ if (buf[3] & ORIG_NAME) {
+ while (ret < LBUFSIZE && buf[ret++] != 0)
+ ;
+ if (unlikely(LBUFSIZE == ret)) {
+ DBG_FLT("binfmt_flat: buffer overflow (ORIG_NAME)?\n");
+ goto out_free_buf;
+ }
+ }
+ if (buf[3] & COMMENT) {
+ while (ret < LBUFSIZE && buf[ret++] != 0)
+ ;
+ if (unlikely(LBUFSIZE == ret)) {
+ DBG_FLT("binfmt_flat: buffer overflow (COMMENT)?\n");
+ goto out_free_buf;
+ }
+ }
+
+ strm.next_in += ret;
+ strm.avail_in -= ret;
+
+ strm.next_out = dst;
+ strm.avail_out = len;
+ strm.total_out = 0;
+
+ if (zlib_inflateInit2(&strm, -MAX_WBITS) != Z_OK) {
+ DBG_FLT("binfmt_flat: zlib init failed?\n");
+ goto out_free_buf;
+ }
+
+ while ((ret = zlib_inflate(&strm, Z_NO_FLUSH)) == Z_OK) {
+ ret = kernel_read(bprm->file, fpos, buf, LBUFSIZE);
+ if (ret <= 0)
+ break;
+ len -= ret;
+
+ strm.next_in = buf;
+ strm.avail_in = ret;
+ strm.total_in = 0;
+ fpos += ret;
+ }
+
+ if (ret < 0) {
+ DBG_FLT("binfmt_flat: decompression failed (%d), %s\n",
+ ret, strm.msg);
+ goto out_zlib;
+ }
+
+ retval = 0;
+out_zlib:
+ zlib_inflateEnd(&strm);
+out_free_buf:
+ kfree(buf);
+out_free:
+ kfree(strm.workspace);
+ return retval;
+}
+
+#endif /* CONFIG_BINFMT_ZFLAT */
+
+/****************************************************************************/
+
+static unsigned long
+calc_reloc(unsigned long r, struct lib_info *p, int curid, int internalp)
+{
+ unsigned long addr;
+ int id;
+ unsigned long start_brk;
+ unsigned long start_data;
+ unsigned long text_len;
+ unsigned long start_code;
+
+#ifdef CONFIG_BINFMT_SHARED_FLAT
+ if (r == 0)
+ id = curid; /* Relocs of 0 are always self referring */
+ else {
+ id = (r >> 24) & 0xff; /* Find ID for this reloc */
+ r &= 0x00ffffff; /* Trim ID off here */
+ }
+ if (id >= MAX_SHARED_LIBS) {
+ printk("BINFMT_FLAT: reference 0x%x to shared library %d",
+ (unsigned) r, id);
+ goto failed;
+ }
+ if (curid != id) {
+ if (internalp) {
+ printk("BINFMT_FLAT: reloc address 0x%x not in same module "
+ "(%d != %d)", (unsigned) r, curid, id);
+ goto failed;
+ } else if ( ! p->lib_list[id].loaded &&
+ IS_ERR_VALUE(load_flat_shared_library(id, p))) {
+ printk("BINFMT_FLAT: failed to load library %d", id);
+ goto failed;
+ }
+ /* Check versioning information (i.e. time stamps) */
+ if (p->lib_list[id].build_date && p->lib_list[curid].build_date &&
+ p->lib_list[curid].build_date < p->lib_list[id].build_date) {
+ printk("BINFMT_FLAT: library %d is younger than %d", id, curid);
+ goto failed;
+ }
+ }
+#else
+ id = 0;
+#endif
+
+ start_brk = p->lib_list[id].start_brk;
+ start_data = p->lib_list[id].start_data;
+ start_code = p->lib_list[id].start_code;
+ text_len = p->lib_list[id].text_len;
+
+ if (!flat_reloc_valid(r, start_brk - start_data + text_len)) {
+ printk("BINFMT_FLAT: reloc outside program 0x%x (0 - 0x%x/0x%x)",
+ (int) r,(int)(start_brk-start_data+text_len),(int)text_len);
+ goto failed;
+ }
+
+ if (r < text_len) /* In text segment */
+ addr = r + start_code;
+ else /* In data segment */
+ addr = r - text_len + start_data;
+
+ /* Range checked already above so doing the range tests is redundant...*/
+ return(addr);
+
+failed:
+ printk(", killing %s!\n", current->comm);
+ send_sig(SIGSEGV, current, 0);
+
+ return RELOC_FAILED;
+}
+
+/****************************************************************************/
+
+static void old_reloc(unsigned long rl)
+{
+#ifdef DEBUG
+ char *segment[] = { "TEXT", "DATA", "BSS", "*UNKNOWN*" };
+#endif
+ flat_v2_reloc_t r;
+ unsigned long *ptr;
+
+ r.value = rl;
+#if defined(CONFIG_COLDFIRE)
+ ptr = (unsigned long *) (current->mm->start_code + r.reloc.offset);
+#else
+ ptr = (unsigned long *) (current->mm->start_data + r.reloc.offset);
+#endif
+
+#ifdef DEBUG
+ printk("Relocation of variable at DATASEG+%x "
+ "(address %p, currently %x) into segment %s\n",
+ r.reloc.offset, ptr, (int)*ptr, segment[r.reloc.type]);
+#endif
+
+ switch (r.reloc.type) {
+ case OLD_FLAT_RELOC_TYPE_TEXT:
+ *ptr += current->mm->start_code;
+ break;
+ case OLD_FLAT_RELOC_TYPE_DATA:
+ *ptr += current->mm->start_data;
+ break;
+ case OLD_FLAT_RELOC_TYPE_BSS:
+ *ptr += current->mm->end_data;
+ break;
+ default:
+ printk("BINFMT_FLAT: Unknown relocation type=%x\n", r.reloc.type);
+ break;
+ }
+
+#ifdef DEBUG
+ printk("Relocation became %x\n", (int)*ptr);
+#endif
+}
+
+/****************************************************************************/
+
+static int load_flat_file(struct linux_binprm * bprm,
+ struct lib_info *libinfo, int id, unsigned long *extra_stack)
+{
+ struct flat_hdr * hdr;
+ unsigned long textpos = 0, datapos = 0, result;
+ unsigned long realdatastart = 0;
+ unsigned long text_len, data_len, bss_len, stack_len, flags;
+ unsigned long full_data;
+ unsigned long len, memp = 0;
+ unsigned long memp_size, extra, rlim;
+ unsigned long *reloc = 0, *rp;
+ struct inode *inode;
+ int i, rev, relocs = 0;
+ loff_t fpos;
+ unsigned long start_code, end_code;
+ int ret;
+
+ hdr = ((struct flat_hdr *) bprm->buf); /* exec-header */
+ inode = file_inode(bprm->file);
+
+ text_len = ntohl(hdr->data_start);
+ data_len = ntohl(hdr->data_end) - ntohl(hdr->data_start);
+ bss_len = ntohl(hdr->bss_end) - ntohl(hdr->data_end);
+ stack_len = ntohl(hdr->stack_size);
+ if (extra_stack) {
+ stack_len += *extra_stack;
+ *extra_stack = stack_len;
+ }
+ relocs = ntohl(hdr->reloc_count);
+ flags = ntohl(hdr->flags);
+ rev = ntohl(hdr->rev);
+ full_data = data_len + relocs * sizeof(unsigned long);
+
+ if (strncmp(hdr->magic, "bFLT", 4)) {
+ /*
+ * Previously, here was a printk to tell people
+ * "BINFMT_FLAT: bad header magic".
+ * But for the kernel which also use ELF FD-PIC format, this
+ * error message is confusing.
+ * because a lot of people do not manage to produce good
+ */
+ ret = -ENOEXEC;
+ goto err;
+ }
+
+ if (flags & FLAT_FLAG_KTRACE)
+ printk("BINFMT_FLAT: Loading file: %s\n", bprm->filename);
+
+ if (rev != FLAT_VERSION && rev != OLD_FLAT_VERSION) {
+ printk("BINFMT_FLAT: bad flat file version 0x%x (supported "
+ "0x%lx and 0x%lx)\n",
+ rev, FLAT_VERSION, OLD_FLAT_VERSION);
+ ret = -ENOEXEC;
+ goto err;
+ }
+
+ /* Don't allow old format executables to use shared libraries */
+ if (rev == OLD_FLAT_VERSION && id != 0) {
+ printk("BINFMT_FLAT: shared libraries are not available before rev 0x%x\n",
+ (int) FLAT_VERSION);
+ ret = -ENOEXEC;
+ goto err;
+ }
+
+ /*
+ * fix up the flags for the older format, there were all kinds
+ * of endian hacks, this only works for the simple cases
+ */
+ if (rev == OLD_FLAT_VERSION && flat_old_ram_flag(flags))
+ flags = FLAT_FLAG_RAM;
+
+#ifndef CONFIG_BINFMT_ZFLAT
+ if (flags & (FLAT_FLAG_GZIP|FLAT_FLAG_GZDATA)) {
+ printk("Support for ZFLAT executables is not enabled.\n");
+ ret = -ENOEXEC;
+ goto err;
+ }
+#endif
+
+ /*
+ * Check initial limits. This avoids letting people circumvent
+ * size limits imposed on them by creating programs with large
+ * arrays in the data or bss.
+ */
+ rlim = rlimit(RLIMIT_DATA);
+ if (rlim >= RLIM_INFINITY)
+ rlim = ~0;
+ if (data_len + bss_len > rlim) {
+ ret = -ENOMEM;
+ goto err;
+ }
+
+ /* Flush all traces of the currently running executable */
+ if (id == 0) {
+ result = flush_old_exec(bprm);
+ if (result) {
+ ret = result;
+ goto err;
+ }
+
+ /* OK, This is the point of no return */
+ set_personality(PER_LINUX_32BIT);
+ setup_new_exec(bprm);
+ }
+
+ /*
+ * calculate the extra space we need to map in
+ */
+ extra = max_t(unsigned long, bss_len + stack_len,
+ relocs * sizeof(unsigned long));
+
+ /*
+ * there are a couple of cases here, the separate code/data
+ * case, and then the fully copied to RAM case which lumps
+ * it all together.
+ */
+ if ((flags & (FLAT_FLAG_RAM|FLAT_FLAG_GZIP)) == 0) {
+ /*
+ * this should give us a ROM ptr, but if it doesn't we don't
+ * really care
+ */
+ DBG_FLT("BINFMT_FLAT: ROM mapping of file (we hope)\n");
+
+ textpos = vm_mmap(bprm->file, 0, text_len, PROT_READ|PROT_EXEC,
+ MAP_PRIVATE|MAP_EXECUTABLE, 0);
+ if (!textpos || IS_ERR_VALUE(textpos)) {
+ if (!textpos)
+ textpos = (unsigned long) -ENOMEM;
+ printk("Unable to mmap process text, errno %d\n", (int)-textpos);
+ ret = textpos;
+ goto err;
+ }
+
+ len = data_len + extra + MAX_SHARED_LIBS * sizeof(unsigned long);
+ len = PAGE_ALIGN(len);
+ realdatastart = vm_mmap(0, 0, len,
+ PROT_READ|PROT_WRITE|PROT_EXEC, MAP_PRIVATE, 0);
+
+ if (realdatastart == 0 || IS_ERR_VALUE(realdatastart)) {
+ if (!realdatastart)
+ realdatastart = (unsigned long) -ENOMEM;
+ printk("Unable to allocate RAM for process data, errno %d\n",
+ (int)-realdatastart);
+ vm_munmap(textpos, text_len);
+ ret = realdatastart;
+ goto err;
+ }
+ datapos = ALIGN(realdatastart +
+ MAX_SHARED_LIBS * sizeof(unsigned long),
+ FLAT_DATA_ALIGN);
+
+ DBG_FLT("BINFMT_FLAT: Allocated data+bss+stack (%d bytes): %x\n",
+ (int)(data_len + bss_len + stack_len), (int)datapos);
+
+ fpos = ntohl(hdr->data_start);
+#ifdef CONFIG_BINFMT_ZFLAT
+ if (flags & FLAT_FLAG_GZDATA) {
+ result = decompress_exec(bprm, fpos, (char *) datapos,
+ full_data, 0);
+ } else
+#endif
+ {
+ result = read_code(bprm->file, datapos, fpos,
+ full_data);
+ }
+ if (IS_ERR_VALUE(result)) {
+ printk("Unable to read data+bss, errno %d\n", (int)-result);
+ vm_munmap(textpos, text_len);
+ vm_munmap(realdatastart, len);
+ ret = result;
+ goto err;
+ }
+
+ reloc = (unsigned long *) (datapos+(ntohl(hdr->reloc_start)-text_len));
+ memp = realdatastart;
+ memp_size = len;
+ } else {
+
+ len = text_len + data_len + extra + MAX_SHARED_LIBS * sizeof(unsigned long);
+ len = PAGE_ALIGN(len);
+ textpos = vm_mmap(0, 0, len,
+ PROT_READ | PROT_EXEC | PROT_WRITE, MAP_PRIVATE, 0);
+
+ if (!textpos || IS_ERR_VALUE(textpos)) {
+ if (!textpos)
+ textpos = (unsigned long) -ENOMEM;
+ printk("Unable to allocate RAM for process text/data, errno %d\n",
+ (int)-textpos);
+ ret = textpos;
+ goto err;
+ }
+
+ realdatastart = textpos + ntohl(hdr->data_start);
+ datapos = ALIGN(realdatastart +
+ MAX_SHARED_LIBS * sizeof(unsigned long),
+ FLAT_DATA_ALIGN);
+
+ reloc = (unsigned long *)
+ (datapos + (ntohl(hdr->reloc_start) - text_len));
+ memp = textpos;
+ memp_size = len;
+#ifdef CONFIG_BINFMT_ZFLAT
+ /*
+ * load it all in and treat it like a RAM load from now on
+ */
+ if (flags & FLAT_FLAG_GZIP) {
+ result = decompress_exec(bprm, sizeof (struct flat_hdr),
+ (((char *) textpos) + sizeof (struct flat_hdr)),
+ (text_len + full_data
+ - sizeof (struct flat_hdr)),
+ 0);
+ memmove((void *) datapos, (void *) realdatastart,
+ full_data);
+ } else if (flags & FLAT_FLAG_GZDATA) {
+ result = read_code(bprm->file, textpos, 0, text_len);
+ if (!IS_ERR_VALUE(result))
+ result = decompress_exec(bprm, text_len, (char *) datapos,
+ full_data, 0);
+ }
+ else
+#endif
+ {
+ result = read_code(bprm->file, textpos, 0, text_len);
+ if (!IS_ERR_VALUE(result))
+ result = read_code(bprm->file, datapos,
+ ntohl(hdr->data_start),
+ full_data);
+ }
+ if (IS_ERR_VALUE(result)) {
+ printk("Unable to read code+data+bss, errno %d\n",(int)-result);
+ vm_munmap(textpos, text_len + data_len + extra +
+ MAX_SHARED_LIBS * sizeof(unsigned long));
+ ret = result;
+ goto err;
+ }
+ }
+
+ if (flags & FLAT_FLAG_KTRACE)
+ printk("Mapping is %x, Entry point is %x, data_start is %x\n",
+ (int)textpos, 0x00ffffff&ntohl(hdr->entry), ntohl(hdr->data_start));
+
+ /* The main program needs a little extra setup in the task structure */
+ start_code = textpos + sizeof (struct flat_hdr);
+ end_code = textpos + text_len;
+ if (id == 0) {
+ current->mm->start_code = start_code;
+ current->mm->end_code = end_code;
+ current->mm->start_data = datapos;
+ current->mm->end_data = datapos + data_len;
+ /*
+ * set up the brk stuff, uses any slack left in data/bss/stack
+ * allocation. We put the brk after the bss (between the bss
+ * and stack) like other platforms.
+ * Userspace code relies on the stack pointer starting out at
+ * an address right at the end of a page.
+ */
+ current->mm->start_brk = datapos + data_len + bss_len;
+ current->mm->brk = (current->mm->start_brk + 3) & ~3;
+ current->mm->context.end_brk = memp + memp_size - stack_len;
+ }
+
+ if (flags & FLAT_FLAG_KTRACE)
+ printk("%s %s: TEXT=%x-%x DATA=%x-%x BSS=%x-%x\n",
+ id ? "Lib" : "Load", bprm->filename,
+ (int) start_code, (int) end_code,
+ (int) datapos,
+ (int) (datapos + data_len),
+ (int) (datapos + data_len),
+ (int) (((datapos + data_len + bss_len) + 3) & ~3));
+
+ text_len -= sizeof(struct flat_hdr); /* the real code len */
+
+ /* Store the current module values into the global library structure */
+ libinfo->lib_list[id].start_code = start_code;
+ libinfo->lib_list[id].start_data = datapos;
+ libinfo->lib_list[id].start_brk = datapos + data_len + bss_len;
+ libinfo->lib_list[id].text_len = text_len;
+ libinfo->lib_list[id].loaded = 1;
+ libinfo->lib_list[id].entry = (0x00ffffff & ntohl(hdr->entry)) + textpos;
+ libinfo->lib_list[id].build_date = ntohl(hdr->build_date);
+
+ /*
+ * We just load the allocations into some temporary memory to
+ * help simplify all this mumbo jumbo
+ *
+ * We've got two different sections of relocation entries.
+ * The first is the GOT which resides at the beginning of the data segment
+ * and is terminated with a -1. This one can be relocated in place.
+ * The second is the extra relocation entries tacked after the image's
+ * data segment. These require a little more processing as the entry is
+ * really an offset into the image which contains an offset into the
+ * image.
+ */
+ if (flags & FLAT_FLAG_GOTPIC) {
+ for (rp = (unsigned long *)datapos; *rp != 0xffffffff; rp++) {
+ unsigned long addr;
+ if (*rp) {
+ addr = calc_reloc(*rp, libinfo, id, 0);
+ if (addr == RELOC_FAILED) {
+ ret = -ENOEXEC;
+ goto err;
+ }
+ *rp = addr;
+ }
+ }
+ }
+
+ /*
+ * Now run through the relocation entries.
+ * We've got to be careful here as C++ produces relocatable zero
+ * entries in the constructor and destructor tables which are then
+ * tested for being not zero (which will always occur unless we're
+ * based from address zero). This causes an endless loop as __start
+ * is at zero. The solution used is to not relocate zero addresses.
+ * This has the negative side effect of not allowing a global data
+ * reference to be statically initialised to _stext (I've moved
+ * __start to address 4 so that is okay).
+ */
+ if (rev > OLD_FLAT_VERSION) {
+ unsigned long persistent = 0;
+ for (i=0; i < relocs; i++) {
+ unsigned long addr, relval;
+
+ /* Get the address of the pointer to be
+ relocated (of course, the address has to be
+ relocated first). */
+ relval = ntohl(reloc[i]);
+ if (flat_set_persistent (relval, &persistent))
+ continue;
+ addr = flat_get_relocate_addr(relval);
+ rp = (unsigned long *) calc_reloc(addr, libinfo, id, 1);
+ if (rp == (unsigned long *)RELOC_FAILED) {
+ ret = -ENOEXEC;
+ goto err;
+ }
+
+ /* Get the pointer's value. */
+ addr = flat_get_addr_from_rp(rp, relval, flags,
+ &persistent);
+ if (addr != 0) {
+ /*
+ * Do the relocation. PIC relocs in the data section are
+ * already in target order
+ */
+ if ((flags & FLAT_FLAG_GOTPIC) == 0)
+ addr = ntohl(addr);
+ addr = calc_reloc(addr, libinfo, id, 0);
+ if (addr == RELOC_FAILED) {
+ ret = -ENOEXEC;
+ goto err;
+ }
+
+ /* Write back the relocated pointer. */
+ flat_put_addr_at_rp(rp, addr, relval);
+ }
+ }
+ } else {
+ for (i=0; i < relocs; i++)
+ old_reloc(ntohl(reloc[i]));
+ }
+
+ flush_icache_range(start_code, end_code);
+
+ /* zero the BSS, BRK and stack areas */
+ memset((void*)(datapos + data_len), 0, bss_len +
+ (memp + memp_size - stack_len - /* end brk */
+ libinfo->lib_list[id].start_brk) + /* start brk */
+ stack_len);
+
+ return 0;
+err:
+ return ret;
+}
+
+
+/****************************************************************************/
+#ifdef CONFIG_BINFMT_SHARED_FLAT
+
+/*
+ * Load a shared library into memory. The library gets its own data
+ * segment (including bss) but not argv/argc/environ.
+ */
+
+static int load_flat_shared_library(int id, struct lib_info *libs)
+{
+ struct linux_binprm bprm;
+ int res;
+ char buf[16];
+
+ memset(&bprm, 0, sizeof(bprm));
+
+ /* Create the file name */
+ sprintf(buf, "/lib/lib%d.so", id);
+
+ /* Open the file up */
+ bprm.filename = buf;
+ bprm.file = open_exec(bprm.filename);
+ res = PTR_ERR(bprm.file);
+ if (IS_ERR(bprm.file))
+ return res;
+
+ bprm.cred = prepare_exec_creds();
+ res = -ENOMEM;
+ if (!bprm.cred)
+ goto out;
+
+ /* We don't really care about recalculating credentials at this point
+ * as we're past the point of no return and are dealing with shared
+ * libraries.
+ */
+ bprm.cred_prepared = 1;
+
+ res = prepare_binprm(&bprm);
+
+ if (!IS_ERR_VALUE(res))
+ res = load_flat_file(&bprm, libs, id, NULL);
+
+ abort_creds(bprm.cred);
+
+out:
+ allow_write_access(bprm.file);
+ fput(bprm.file);
+
+ return(res);
+}
+
+#endif /* CONFIG_BINFMT_SHARED_FLAT */
+/****************************************************************************/
+
+/*
+ * These are the functions used to load flat style executables and shared
+ * libraries. There is no binary dependent code anywhere else.
+ */
+
+static int load_flat_binary(struct linux_binprm * bprm)
+{
+ struct lib_info libinfo;
+ struct pt_regs *regs = current_pt_regs();
+ unsigned long p = bprm->p;
+ unsigned long stack_len;
+ unsigned long start_addr;
+ unsigned long *sp;
+ int res;
+ int i, j;
+
+ memset(&libinfo, 0, sizeof(libinfo));
+ /*
+ * We have to add the size of our arguments to our stack size
+ * otherwise it's too easy for users to create stack overflows
+ * by passing in a huge argument list. And yes, we have to be
+ * pedantic and include space for the argv/envp array as it may have
+ * a lot of entries.
+ */
+#define TOP_OF_ARGS (PAGE_SIZE * MAX_ARG_PAGES - sizeof(void *))
+ stack_len = TOP_OF_ARGS - bprm->p; /* the strings */
+ stack_len += (bprm->argc + 1) * sizeof(char *); /* the argv array */
+ stack_len += (bprm->envc + 1) * sizeof(char *); /* the envp array */
+ stack_len += FLAT_STACK_ALIGN - 1; /* reserve for upcoming alignment */
+
+ res = load_flat_file(bprm, &libinfo, 0, &stack_len);
+ if (IS_ERR_VALUE(res))
+ return res;
+
+ /* Update data segment pointers for all libraries */
+ for (i=0; i<MAX_SHARED_LIBS; i++)
+ if (libinfo.lib_list[i].loaded)
+ for (j=0; j<MAX_SHARED_LIBS; j++)
+ (-(j+1))[(unsigned long *)(libinfo.lib_list[i].start_data)] =
+ (libinfo.lib_list[j].loaded)?
+ libinfo.lib_list[j].start_data:UNLOADED_LIB;
+
+ install_exec_creds(bprm);
+
+ set_binfmt(&flat_format);
+
+ p = ((current->mm->context.end_brk + stack_len + 3) & ~3) - 4;
+ DBG_FLT("p=%x\n", (int)p);
+
+ /* copy the arg pages onto the stack, this could be more efficient :-) */
+ for (i = TOP_OF_ARGS - 1; i >= bprm->p; i--)
+ * (char *) --p =
+ ((char *) page_address(bprm->page[i/PAGE_SIZE]))[i % PAGE_SIZE];
+
+ sp = (unsigned long *) create_flat_tables(p, bprm);
+
+ /* Fake some return addresses to ensure the call chain will
+ * initialise library in order for us. We are required to call
+ * lib 1 first, then 2, ... and finally the main program (id 0).
+ */
+ start_addr = libinfo.lib_list[0].entry;
+
+#ifdef CONFIG_BINFMT_SHARED_FLAT
+ for (i = MAX_SHARED_LIBS-1; i>0; i--) {
+ if (libinfo.lib_list[i].loaded) {
+ /* Push previos first to call address */
+ --sp; put_user(start_addr, sp);
+ start_addr = libinfo.lib_list[i].entry;
+ }
+ }
+#endif
+
+ /* Stash our initial stack pointer into the mm structure */
+ current->mm->start_stack = (unsigned long )sp;
+
+#ifdef FLAT_PLAT_INIT
+ FLAT_PLAT_INIT(regs);
+#endif
+ DBG_FLT("start_thread(regs=0x%x, entry=0x%x, start_stack=0x%x)\n",
+ (int)regs, (int)start_addr, (int)current->mm->start_stack);
+
+ start_thread(regs, start_addr, current->mm->start_stack);
+
+ return 0;
+}
+
+/****************************************************************************/
+
+static int __init init_flat_binfmt(void)
+{
+ register_binfmt(&flat_format);
+ return 0;
+}
+
+/****************************************************************************/
+
+core_initcall(init_flat_binfmt);
+
+/****************************************************************************/
Code Review / kvmfornfv.git / blobdiff