Release 4.7 fs/binfmt_flat.c
/****************************************************************************/
/*
* 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);
}
Contributors
| Person | Tokens | Prop | Commits | CommitProp |
greg ungerer | greg ungerer | 31 | 81.58% | 1 | 33.33% |
masami hiramatsu | masami hiramatsu | 4 | 10.53% | 1 | 33.33% |
denys vlasenko | denys vlasenko | 3 | 7.89% | 1 | 33.33% |
| Total | 38 | 100.00% | 3 | 100.00% |
/****************************************************************************/
/*
* 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;
}
Contributors
| Person | Tokens | Prop | Commits | CommitProp |
alan cox | alan cox | 265 | 82.04% | 1 | 16.67% |
oskar schirmer | oskar schirmer | 46 | 14.24% | 1 | 16.67% |
greg ungerer | greg ungerer | 8 | 2.48% | 2 | 33.33% |
andrew morton | andrew morton | 3 | 0.93% | 1 | 16.67% |
mike frysinger | mike frysinger | 1 | 0.31% | 1 | 16.67% |
| Total | 323 | 100.00% | 6 | 100.00% |
/****************************************************************************/
#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;
}
Contributors
| Person | Tokens | Prop | Commits | CommitProp |
alan cox | alan cox | 483 | 78.54% | 1 | 16.67% |
greg ungerer | greg ungerer | 109 | 17.72% | 3 | 50.00% |
al viro | al viro | 14 | 2.28% | 1 | 16.67% |
volodymyr g. lukiianyk | volodymyr g. lukiianyk | 9 | 1.46% | 1 | 16.67% |
| Total | 615 | 100.00% | 6 | 100.00% |
#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 &&
load_flat_shared_library(id, p) < 0) {
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;
}
Contributors
| Person | Tokens | Prop | Commits | CommitProp |
greg ungerer | greg ungerer | 274 | 74.25% | 1 | 25.00% |
alan cox | alan cox | 90 | 24.39% | 1 | 25.00% |
jun sun | jun sun | 3 | 0.81% | 1 | 25.00% |
arnd bergmann | arnd bergmann | 2 | 0.54% | 1 | 25.00% |
| Total | 369 | 100.00% | 4 | 100.00% |
/****************************************************************************/
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
}
Contributors
| Person | Tokens | Prop | Commits | CommitProp |
alan cox | alan cox | 207 | 99.52% | 1 | 50.00% |
axel lin | axel lin | 1 | 0.48% | 1 | 50.00% |
| Total | 208 | 100.00% | 2 | 100.00% |
/****************************************************************************/
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