--- /dev/null
+/*
+ * linux/fs/binfmt_flat.c
+ *
+ * Copyright (C) 2000, 2001 Lineo, by David McCullough <davidm@uclinux.org>
+ * Copyright (C) 2002 Greg Ungerer <gerg@snapgear.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/module.h>
+#include <linux/config.h>
+#include <linux/kernel.h>
+#include <linux/sched.h>
+#include <linux/mm.h>
+#include <linux/mman.h>
+#include <linux/a.out.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 <asm/byteorder.h>
+#include <asm/system.h>
+#include <asm/uaccess.h>
+#include <asm/pgalloc.h>
+#include <asm/unaligned.h>
+#include <asm/cacheflush.h>
+
+#undef DEBUG
+#ifdef DEBUG
+#define DBG_FLT(a...) printk(##a)
+#else
+#define DBG_FLT(a...)
+#endif
+
+static int load_flat_binary(struct linux_binprm *, struct pt_regs * regs);
+static int load_flat_library(struct file*);
+extern void dump_thread(struct pt_regs *, struct user *);
+
+static struct linux_binfmt flat_format = {
+ NULL, THIS_MODULE, load_flat_binary, load_flat_library, NULL, PAGE_SIZE
+};
+
+
+/*
+ * 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 dummy;
+
+ sp = (unsigned long *) ((-(unsigned long)sizeof(char *))&(unsigned long) p);
+
+ sp -= envc+1;
+ envp = sp;
+ sp -= argc+1;
+ argv = sp;
+ put_user((unsigned long) envp, --sp);
+ put_user((unsigned long) argv, --sp);
+ 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;
+
+ 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");
+ return -ENOMEM;
+ }
+
+ /* Read in first chunk of data and parse gzip header. */
+ fpos = offset;
+ ret = bprm->file->f_op->read(bprm->file, buf, LBUFSIZE, &fpos);
+
+ strm.next_in = buf;
+ strm.avail_in = ret;
+ strm.total_in = 0;
+
+ /* Check minimum size -- gzip header */
+ if (ret < 10) {
+ DBG_FLT("binfmt_flat: file too small?\n");
+ return -ENOEXEC;
+ }
+
+ /* Check gzip magic number */
+ if ((buf[0] != 037) || ((buf[1] != 0213) && (buf[1] != 0236))) {
+ DBG_FLT("binfmt_flat: unknown compression magic?\n");
+ return -ENOEXEC;
+ }
+
+ /* Check gzip method */
+ if (buf[2] != 8) {
+ DBG_FLT("binfmt_flat: unknown compression method?\n");
+ return -ENOEXEC;
+ }
+ /* Check gzip flags */
+ if ((buf[3] & ENCRYPTED) || (buf[3] & CONTINUATION) ||
+ (buf[3] & RESERVED)) {
+ DBG_FLT("binfmt_flat: unknown flags?\n");
+ return -ENOEXEC;
+ }
+
+ ret = 10;
+ if (buf[3] & EXTRA_FIELD)
+ ret += 2 + buf[10] + (buf[11] << 8);
+ if (buf[3] & ORIG_NAME) {
+ for (; (buf[ret] != 0); ret++)
+ ;
+ }
+ if (buf[3] & COMMENT) {
+ for (; (buf[ret] != 0); ret++)
+ ;
+ }
+
+ 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");
+ return -ENOEXEC;
+ }
+
+ while ((ret = zlib_inflate(&strm, Z_NO_FLUSH)) == Z_OK) {
+ ret = bprm->file->f_op->read(bprm->file, buf, LBUFSIZE, &fpos);
+ if (ret == 0)
+ break;
+ if (ret >= (unsigned long) -4096)
+ break;
+ len -= ret;
+
+ strm.next_in = buf;
+ strm.avail_in = ret;
+ strm.total_in = 0;
+ }
+
+ if (ret < 0) {
+ DBG_FLT("binfmt_flat: decompression failed (%d), %s\n",
+ ret, strm.msg);
+ return -ENOEXEC;
+ }
+
+ zlib_inflateEnd(&strm);
+ kfree(buf);
+ kfree(strm.workspace);
+ return 0;
+}
+
+#endif /* CONFIG_BINFMT_ZFLAT */
+
+
+static unsigned long
+calc_reloc(unsigned long r, unsigned long text_len)
+{
+ unsigned long addr;
+
+ if (r > current->mm->start_brk - current->mm->start_data + text_len) {
+ printk("BINFMT_FLAT: reloc outside program 0x%x (0 - 0x%x), killing!\n",
+ (int) r,(int)(current->mm->start_brk-current->mm->start_code));
+ send_sig(SIGSEGV, current, 0);
+ return(current->mm->start_brk); /* return something safe to write to */
+ }
+
+ if (r < text_len) {
+ /* In text segment */
+ return r + current->mm->start_code;
+ }
+
+ /*
+ * we allow inclusive ranges here so that programs may do things
+ * like reference the end of data (_end) without failing these tests
+ */
+ addr = r - text_len + current->mm->start_data;
+ if (addr >= current->mm->start_code &&
+ addr <= current->mm->start_code + text_len)
+ return(addr);
+
+ if (addr >= current->mm->start_data &&
+ addr <= current->mm->start_brk)
+ return(addr);
+
+ printk("BINFMT_FLAT: reloc addr outside text/data 0x%x "
+ "code(0x%x - 0x%x) data(0x%x - 0x%x) killing\n", (int) addr,
+ (int) current->mm->start_code,
+ (int) (current->mm->start_code + text_len),
+ (int) current->mm->start_data,
+ (int) current->mm->start_brk);
+ send_sig(SIGSEGV, current, 0);
+
+ return(current->mm->start_brk); /* return something safe to write to */
+}
+
+
+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
+}
+
+
+/*
+ * 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 pt_regs * regs)
+{
+ struct flat_hdr * hdr;
+ unsigned long textpos = 0, datapos = 0, result;
+ unsigned long text_len, data_len, bss_len, stack_len, flags;
+ unsigned long memp = 0, memkasked = 0; /* for finding the brk area */
+ unsigned long extra, rlim;
+ unsigned long p = bprm->p;
+ unsigned long *reloc = 0, *rp;
+ struct inode *inode;
+ int i, rev, relocs = 0;
+ loff_t fpos;
+
+ DBG_FLT("BINFMT_FLAT: Loading file: %x\n", bprm->file);
+
+ hdr = ((struct flat_hdr *) bprm->buf); /* exec-header */
+ inode = bprm->file->f_dentry->d_inode;
+
+ 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);
+ relocs = ntohl(hdr->reloc_count);
+ flags = ntohl(hdr->flags);
+ rev = ntohl(hdr->rev);
+
+ /*
+ * 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 */
+
+ if (strncmp(hdr->magic, "bFLT", 4) ||
+ (rev != FLAT_VERSION && rev != OLD_FLAT_VERSION)) {
+ /*
+ * because a lot of people do not manage to produce good
+ * flat binaries, we leave this printk to help them realise
+ * the problem. We only print the error if its * not a script file
+ */
+ if (strncmp(hdr->magic, "#!", 2))
+ printk("BINFMT_FLAT: bad magic/rev (0x%x, need 0x%x)\n",
+ rev, (int) FLAT_VERSION);
+ return -ENOEXEC;
+ }
+
+ /*
+ * 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 && 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");
+ return -ENOEXEC;
+ }
+#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 = current->rlim[RLIMIT_DATA].rlim_cur;
+ if (rlim >= RLIM_INFINITY)
+ rlim = ~0;
+ if (data_len + bss_len > rlim)
+ return -ENOMEM;
+
+ /* Flush all traces of the currently running executable */
+ result = flush_old_exec(bprm);
+ if (result)
+ return result;
+
+ /* OK, This is the point of no return */
+ set_personality(PER_LINUX);
+
+ /*
+ * there are a couple of cases here, the seperate 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");
+
+ down_write(¤t->mm->mmap_sem);
+ textpos = do_mmap(bprm->file, 0, text_len, PROT_READ|PROT_EXEC, 0, 0);
+ up_write(¤t->mm->mmap_sem);
+ if (!textpos || textpos >= (unsigned long) -4096) {
+ if (!textpos)
+ textpos = (unsigned long) -ENOMEM;
+ printk("Unable to mmap process text, errno %d\n", (int)-textpos);
+ }
+
+ extra = max(bss_len + stack_len, relocs * sizeof(unsigned long)),
+
+ down_write(¤t->mm->mmap_sem);
+ datapos = do_mmap(0, 0, data_len + extra,
+ PROT_READ|PROT_WRITE|PROT_EXEC, 0, 0);
+ up_write(¤t->mm->mmap_sem);
+
+ if (datapos == 0 || datapos >= (unsigned long)-4096) {
+ if (!datapos)
+ datapos = (unsigned long) -ENOMEM;
+ printk("Unable to allocate RAM for process data, errno %d\n",
+ (int)-datapos);
+ do_munmap(current->mm, textpos, text_len);
+ return datapos;
+ }
+
+ DBG_FLT("BINFMT_FLAT: Allocated data+bss+stack (%d bytes): %x\n",
+ data_len + bss_len + stack_len, datapos);
+
+ fpos = ntohl(hdr->data_start);
+#ifdef CONFIG_BINFMT_ZFLAT
+ if (flags & FLAT_FLAG_GZDATA) {
+ result = decompress_exec(bprm, fpos, (char *) datapos,
+ data_len + (relocs * sizeof(unsigned long)), 0);
+ } else
+#endif
+ {
+ result = bprm->file->f_op->read(bprm->file,
+ (char *) datapos, data_len + extra, &fpos);
+ }
+ if (result >= (unsigned long)-4096) {
+ printk("Unable to read data+bss, errno %d\n", (int)-result);
+ do_munmap(current->mm, textpos, text_len);
+ do_munmap(current->mm, datapos, data_len + extra);
+ return result;
+ }
+
+ reloc = (unsigned long *) (datapos+(ntohl(hdr->reloc_start)-text_len));
+ memp = datapos;
+ memkasked = data_len + extra;
+
+ } else {
+
+ /*
+ * calculate the extra space we need to map in
+ */
+
+ extra = max(bss_len + stack_len, relocs * sizeof(unsigned long)),
+
+ down_write(¤t->mm->mmap_sem);
+ textpos = do_mmap(0, 0, text_len + data_len + extra,
+ PROT_READ | PROT_EXEC | PROT_WRITE, 0, 0);
+ up_write(¤t->mm->mmap_sem);
+ if (!textpos || textpos >= (unsigned long) -4096) {
+ if (!textpos)
+ textpos = (unsigned long) -ENOMEM;
+ printk("Unable to allocate RAM for process text/data, errno %d\n",
+ (int)-textpos);
+ }
+
+ datapos = textpos + ntohl (hdr->data_start);
+ reloc = (unsigned long *) (textpos + ntohl(hdr->reloc_start));
+ memp = textpos;
+ memkasked = text_len + data_len + extra;
+
+#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 + data_len + (relocs * sizeof(unsigned long))
+ - sizeof (struct flat_hdr)),
+ 0);
+ } else if (flags & FLAT_FLAG_GZDATA) {
+ fpos = 0;
+ result = bprm->file->f_op->read(bprm->file,
+ (char *) textpos, text_len, &fpos);
+ if (result < (unsigned long) -4096)
+ result = decompress_exec(bprm, text_len, (char *) datapos,
+ data_len + (relocs * sizeof(unsigned long)), 0);
+ }
+ else
+#endif
+ {
+ fpos = 0;
+ result = bprm->file->f_op->read(bprm->file,
+ (char *) textpos, text_len + data_len + extra, &fpos);
+ }
+ if (result >= (unsigned long)-4096) {
+ printk("Unable to read code+data+bss, errno %d\n",(int)-result);
+ do_munmap(current->mm, textpos, text_len + data_len + extra);
+ return result;
+ }
+ }
+
+ DBG_FLT("Mapping is %x, Entry point is %x, data_start is %x\n",
+ textpos, ntohl(hdr->entry), ntohl(hdr->data_start));
+
+ current->mm->start_code = textpos + sizeof (struct flat_hdr);
+ current->mm->end_code = textpos + text_len;
+ 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.
+ */
+ current->mm->start_brk = datapos + data_len + bss_len;
+ current->mm->brk = (current->mm->start_brk + 3) & ~3;
+ current->mm->context.end_brk = memp + ksize((void *) memp) - stack_len;
+ current->mm->rss = 0;
+
+ DBG_FLT("Load %s: TEXT=%x-%x DATA=%x-%x BSS=%x-%x\n",
+ bprm->filename,
+ (int) current->mm->start_code, (int) current->mm->end_code,
+ (int) current->mm->start_data, (int) current->mm->end_data,
+ (int) current->mm->end_data, (int) current->mm->brk);
+
+ text_len -= sizeof(struct flat_hdr); /* the real code len */
+
+ /*
+ * 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 begining 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++)
+ *rp = calc_reloc(*rp, text_len);
+ }
+
+ /*
+ * 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) {
+ for (i=0; i < relocs; i++) {
+ unsigned long addr;
+
+ /* Get the address of the pointer to be
+ relocated (of course, the address has to be
+ relocated first). */
+ rp = (unsigned long *) calc_reloc(ntohl(reloc[i]), text_len);
+
+ /* Get the pointer's value. */
+ addr = get_unaligned (rp);
+
+ if (addr != 0) {
+ /*
+ * Do the relocation. PIC relocs in the data section are
+ * already in target order
+ */
+ addr = calc_reloc(
+ (flags & FLAT_FLAG_GOTPIC) ? addr : ntohl(addr),
+ text_len);
+ /* Write back the relocated pointer. */
+ put_unaligned (addr, rp);
+ }
+ }
+ } else {
+ for (i=0; i < relocs; i++)
+ old_reloc(ntohl(reloc[i]));
+ }
+
+ /* zero the BSS, BRK and stack areas */
+ memset((void*)(datapos + data_len), 0, bss_len +
+ (current->mm->context.end_brk - current->mm->start_brk) +
+ stack_len);
+
+ compute_creds(bprm);
+ current->flags &= ~PF_FORKNOEXEC;
+
+ flush_icache_range(current->mm->start_code, current->mm->end_code);
+
+ set_binfmt(&flat_format);
+
+ p = ((current->mm->context.end_brk + stack_len + 3) & ~3) - 4;
+ DBG_FLT("p=%x\n", 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];
+
+ current->mm->start_stack = (unsigned long) create_flat_tables(p, bprm);
+
+ DBG_FLT("start_thread(regs=0x%x, entry=0x%x, start_stack=0x%x)\n",
+ regs, textpos + ntohl(hdr->entry), current->mm->start_stack);
+ start_thread(regs,
+ textpos + ntohl(hdr->entry),
+ current->mm->start_stack);
+
+ if (current->ptrace & PT_PTRACED)
+ send_sig(SIGTRAP, current, 0);
+
+ return 0;
+}
+
+static int load_flat_library(struct file *file)
+{
+ return(-ENOEXEC);
+}
+
+static int __init init_flat_binfmt(void)
+{
+ return register_binfmt(&flat_format);
+}
+
+static void __exit exit_flat_binfmt(void)
+{
+ unregister_binfmt(&flat_format);
+}
+
+EXPORT_NO_SYMBOLS;
+
+module_init(init_flat_binfmt);
+module_exit(exit_flat_binfmt);
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