root / linux-user / elfload.c @ 3ef693a0
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/* This is the Linux kernel elf-loading code, ported into user space */
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#include <stdio.h> |
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#include <sys/types.h> |
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#include <fcntl.h> |
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#include <sys/stat.h> |
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#include <errno.h> |
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#include <unistd.h> |
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#include <sys/mman.h> |
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#include <stdlib.h> |
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#include <string.h> |
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#include "qemu.h" |
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#include "linux_bin.h" |
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#include "elf.h" |
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#include "segment.h" |
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/* Necessary parameters */
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#define ALPHA_PAGE_SIZE 4096 |
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#define X86_PAGE_SIZE 4096 |
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#define ALPHA_PAGE_MASK (~(ALPHA_PAGE_SIZE-1)) |
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#define X86_PAGE_MASK (~(X86_PAGE_SIZE-1)) |
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#define ALPHA_PAGE_ALIGN(addr) ((((addr)+ALPHA_PAGE_SIZE)-1)&ALPHA_PAGE_MASK) |
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#define X86_PAGE_ALIGN(addr) ((((addr)+X86_PAGE_SIZE)-1)&X86_PAGE_MASK) |
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#define NGROUPS 32 |
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#define X86_ELF_EXEC_PAGESIZE X86_PAGE_SIZE
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#define X86_ELF_PAGESTART(_v) ((_v) & ~(unsigned long)(X86_ELF_EXEC_PAGESIZE-1)) |
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#define X86_ELF_PAGEOFFSET(_v) ((_v) & (X86_ELF_EXEC_PAGESIZE-1)) |
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#define ALPHA_ELF_PAGESTART(_v) ((_v) & ~(unsigned long)(ALPHA_PAGE_SIZE-1)) |
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#define ALPHA_ELF_PAGEOFFSET(_v) ((_v) & (ALPHA_PAGE_SIZE-1)) |
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#define INTERPRETER_NONE 0 |
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#define INTERPRETER_AOUT 1 |
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#define INTERPRETER_ELF 2 |
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#define DLINFO_ITEMS 12 |
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/* Where we find X86 libraries... */
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//#define X86_DEFAULT_LIB_DIR "/usr/x86/"
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#define X86_DEFAULT_LIB_DIR "/" |
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//extern void * mmap4k();
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#define mmap4k(a, b, c, d, e, f) mmap((void *)(a), b, c, d, e, f) |
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extern unsigned long x86_stack_size; |
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static int load_aout_interp(void * exptr, int interp_fd); |
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#ifdef BSWAP_NEEDED
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static void bswap_ehdr(Elf32_Ehdr *ehdr) |
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{
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bswap16s(&ehdr->e_type); /* Object file type */
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bswap16s(&ehdr->e_machine); /* Architecture */
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bswap32s(&ehdr->e_version); /* Object file version */
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bswap32s(&ehdr->e_entry); /* Entry point virtual address */
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bswap32s(&ehdr->e_phoff); /* Program header table file offset */
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bswap32s(&ehdr->e_shoff); /* Section header table file offset */
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bswap32s(&ehdr->e_flags); /* Processor-specific flags */
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bswap16s(&ehdr->e_ehsize); /* ELF header size in bytes */
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bswap16s(&ehdr->e_phentsize); /* Program header table entry size */
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bswap16s(&ehdr->e_phnum); /* Program header table entry count */
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bswap16s(&ehdr->e_shentsize); /* Section header table entry size */
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bswap16s(&ehdr->e_shnum); /* Section header table entry count */
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bswap16s(&ehdr->e_shstrndx); /* Section header string table index */
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} |
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static void bswap_phdr(Elf32_Phdr *phdr) |
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{
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bswap32s(&phdr->p_type); /* Segment type */
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bswap32s(&phdr->p_offset); /* Segment file offset */
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bswap32s(&phdr->p_vaddr); /* Segment virtual address */
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bswap32s(&phdr->p_paddr); /* Segment physical address */
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bswap32s(&phdr->p_filesz); /* Segment size in file */
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bswap32s(&phdr->p_memsz); /* Segment size in memory */
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bswap32s(&phdr->p_flags); /* Segment flags */
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bswap32s(&phdr->p_align); /* Segment alignment */
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} |
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#endif
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static void * get_free_page(void) |
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{
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void * retval;
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/* User-space version of kernel get_free_page. Returns a page-aligned
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* page-sized chunk of memory.
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*/
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retval = mmap4k(0, ALPHA_PAGE_SIZE, PROT_READ|PROT_WRITE,
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MAP_PRIVATE|MAP_ANONYMOUS, -1, 0); |
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if((long)retval == -1) { |
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perror("get_free_page");
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exit(-1);
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} |
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else {
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return(retval);
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} |
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} |
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static void free_page(void * pageaddr) |
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{
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(void)munmap(pageaddr, ALPHA_PAGE_SIZE);
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} |
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/*
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* 'copy_string()' copies argument/envelope strings from user
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* memory to free pages in kernel mem. These are in a format ready
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* to be put directly into the top of new user memory.
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*
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*/
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static unsigned long copy_strings(int argc,char ** argv,unsigned long *page, |
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unsigned long p) |
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{
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char *tmp, *tmp1, *pag = NULL; |
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int len, offset = 0; |
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if (!p) {
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return 0; /* bullet-proofing */ |
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} |
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while (argc-- > 0) { |
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if (!(tmp1 = tmp = get_user(argv+argc))) {
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fprintf(stderr, "VFS: argc is wrong");
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exit(-1);
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} |
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while (get_user(tmp++));
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len = tmp - tmp1; |
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if (p < len) { /* this shouldn't happen - 128kB */ |
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return 0; |
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} |
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while (len) {
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--p; --tmp; --len; |
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if (--offset < 0) { |
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offset = p % X86_PAGE_SIZE; |
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if (!(pag = (char *) page[p/X86_PAGE_SIZE]) && |
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!(pag = (char *) page[p/X86_PAGE_SIZE] =
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(unsigned long *) get_free_page())) { |
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return 0; |
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} |
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} |
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if (len == 0 || offset == 0) { |
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*(pag + offset) = get_user(tmp); |
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} |
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else {
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int bytes_to_copy = (len > offset) ? offset : len;
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tmp -= bytes_to_copy; |
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p -= bytes_to_copy; |
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offset -= bytes_to_copy; |
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len -= bytes_to_copy; |
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memcpy_fromfs(pag + offset, tmp, bytes_to_copy + 1);
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} |
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} |
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} |
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return p;
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} |
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static int in_group_p(gid_t g) |
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{
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/* return TRUE if we're in the specified group, FALSE otherwise */
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int ngroup;
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int i;
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gid_t grouplist[NGROUPS]; |
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ngroup = getgroups(NGROUPS, grouplist); |
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for(i = 0; i < ngroup; i++) { |
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if(grouplist[i] == g) {
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return 1; |
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} |
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} |
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return 0; |
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} |
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static int count(char ** vec) |
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{
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int i;
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for(i = 0; *vec; i++) { |
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vec++; |
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} |
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return(i);
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} |
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static int prepare_binprm(struct linux_binprm *bprm) |
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{
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struct stat st;
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int mode;
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int retval, id_change;
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if(fstat(bprm->fd, &st) < 0) { |
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return(-errno);
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} |
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mode = st.st_mode; |
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if(!S_ISREG(mode)) { /* Must be regular file */ |
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return(-EACCES);
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} |
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if(!(mode & 0111)) { /* Must have at least one execute bit set */ |
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return(-EACCES);
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} |
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bprm->e_uid = geteuid(); |
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bprm->e_gid = getegid(); |
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id_change = 0;
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/* Set-uid? */
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if(mode & S_ISUID) {
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bprm->e_uid = st.st_uid; |
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if(bprm->e_uid != geteuid()) {
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id_change = 1;
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} |
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} |
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/* Set-gid? */
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/*
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* If setgid is set but no group execute bit then this
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* is a candidate for mandatory locking, not a setgid
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* executable.
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*/
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if ((mode & (S_ISGID | S_IXGRP)) == (S_ISGID | S_IXGRP)) {
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bprm->e_gid = st.st_gid; |
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if (!in_group_p(bprm->e_gid)) {
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id_change = 1;
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} |
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} |
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memset(bprm->buf, 0, sizeof(bprm->buf)); |
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retval = lseek(bprm->fd, 0L, SEEK_SET);
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if(retval >= 0) { |
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retval = read(bprm->fd, bprm->buf, 128);
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} |
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if(retval < 0) { |
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perror("prepare_binprm");
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exit(-1);
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/* return(-errno); */
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} |
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else {
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return(retval);
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} |
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} |
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unsigned long setup_arg_pages(unsigned long p, struct linux_binprm * bprm, |
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struct image_info * info)
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{
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unsigned long stack_base; |
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int i;
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extern unsigned long stktop; |
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stack_base = X86_STACK_TOP - MAX_ARG_PAGES*X86_PAGE_SIZE; |
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p += stack_base; |
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if (bprm->loader) {
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bprm->loader += stack_base; |
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} |
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bprm->exec += stack_base; |
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/* Create enough stack to hold everything. If we don't use
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* it for args, we'll use it for something else...
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*/
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/* XXX: on x86 MAP_GROWSDOWN only works if ESP <= address + 32, so
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we allocate a bigger stack. Need a better solution, for example
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by remapping the process stack directly at the right place */
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if(x86_stack_size > MAX_ARG_PAGES*X86_PAGE_SIZE) {
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if((long)mmap4k((void *)(X86_STACK_TOP-x86_stack_size), x86_stack_size + X86_PAGE_SIZE, |
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PROT_READ | PROT_WRITE, |
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MAP_GROWSDOWN | MAP_FIXED | MAP_PRIVATE | MAP_ANONYMOUS, -1, 0) == -1) { |
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perror("stk mmap");
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exit(-1);
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} |
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} |
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else {
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if((long)mmap4k((void *)stack_base, (MAX_ARG_PAGES+1)*X86_PAGE_SIZE, |
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PROT_READ | PROT_WRITE, |
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MAP_GROWSDOWN | MAP_FIXED | MAP_PRIVATE | MAP_ANONYMOUS, -1, 0) == -1) { |
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perror("stk mmap");
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exit(-1);
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} |
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} |
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stktop = stack_base; |
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for (i = 0 ; i < MAX_ARG_PAGES ; i++) { |
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if (bprm->page[i]) {
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info->rss++; |
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memcpy((void *)stack_base, (void *)bprm->page[i], X86_PAGE_SIZE); |
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free_page((void *)bprm->page[i]);
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} |
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stack_base += X86_PAGE_SIZE; |
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} |
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return p;
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} |
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static void set_brk(unsigned long start, unsigned long end) |
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{
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/* page-align the start and end addresses... */
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start = ALPHA_PAGE_ALIGN(start); |
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end = ALPHA_PAGE_ALIGN(end); |
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if (end <= start)
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return;
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if((long)mmap4k(start, end - start, |
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PROT_READ | PROT_WRITE | PROT_EXEC, |
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MAP_FIXED | MAP_PRIVATE | MAP_ANONYMOUS, -1, 0) == -1) { |
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perror("cannot mmap brk");
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exit(-1);
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} |
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} |
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/* We need to explicitly zero any fractional pages
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after the data section (i.e. bss). This would
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contain the junk from the file that should not
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be in memory */
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static void padzero(unsigned long elf_bss) |
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{
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unsigned long nbyte; |
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char * fpnt;
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nbyte = elf_bss & (ALPHA_PAGE_SIZE-1); /* was X86_PAGE_SIZE - JRP */ |
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if (nbyte) {
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nbyte = ALPHA_PAGE_SIZE - nbyte; |
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fpnt = (char *) elf_bss;
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do {
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*fpnt++ = 0;
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} while (--nbyte);
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} |
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} |
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|
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static unsigned int * create_elf_tables(char *p, int argc, int envc, |
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struct elfhdr * exec,
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unsigned long load_addr, |
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unsigned long interp_load_addr, int ibcs, |
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struct image_info *info)
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{
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target_ulong *argv, *envp, *dlinfo; |
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target_ulong *sp; |
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/*
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* Force 16 byte alignment here for generality.
|
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*/
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sp = (unsigned int *) (~15UL & (unsigned long) p); |
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sp -= exec ? DLINFO_ITEMS*2 : 2; |
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dlinfo = sp; |
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sp -= envc+1;
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envp = sp; |
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sp -= argc+1;
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argv = sp; |
| 354 |
if (!ibcs) {
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put_user(tswapl((target_ulong)envp),--sp); |
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put_user(tswapl((target_ulong)argv),--sp); |
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} |
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|
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#define NEW_AUX_ENT(id, val) \
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put_user (tswapl(id), dlinfo++); \ |
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put_user (tswapl(val), dlinfo++) |
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|
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if (exec) { /* Put this here for an ELF program interpreter */ |
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struct elf_phdr * eppnt;
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eppnt = (struct elf_phdr *)((unsigned long)exec->e_phoff); |
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NEW_AUX_ENT (AT_PHDR, (unsigned int)(load_addr + exec->e_phoff)); |
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NEW_AUX_ENT (AT_PHENT, (unsigned int)(sizeof (struct elf_phdr))); |
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NEW_AUX_ENT (AT_PHNUM, (unsigned int)(exec->e_phnum)); |
| 370 |
NEW_AUX_ENT (AT_PAGESZ, (unsigned int)(ALPHA_PAGE_SIZE)); |
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NEW_AUX_ENT (AT_BASE, (unsigned int)(interp_load_addr)); |
| 372 |
NEW_AUX_ENT (AT_FLAGS, (unsigned int)0); |
| 373 |
NEW_AUX_ENT (AT_ENTRY, (unsigned int) exec->e_entry); |
| 374 |
NEW_AUX_ENT (AT_UID, (unsigned int) getuid()); |
| 375 |
NEW_AUX_ENT (AT_EUID, (unsigned int) geteuid()); |
| 376 |
NEW_AUX_ENT (AT_GID, (unsigned int) getgid()); |
| 377 |
NEW_AUX_ENT (AT_EGID, (unsigned int) getegid()); |
| 378 |
} |
| 379 |
NEW_AUX_ENT (AT_NULL, 0);
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#undef NEW_AUX_ENT
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put_user(tswapl(argc),--sp); |
| 382 |
info->arg_start = (unsigned int)((unsigned long)p & 0xffffffff); |
| 383 |
while (argc-->0) { |
| 384 |
put_user(tswapl((target_ulong)p),argv++); |
| 385 |
while (get_user(p++)) /* nothing */ ; |
| 386 |
} |
| 387 |
put_user(0,argv);
|
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info->arg_end = info->env_start = (unsigned int)((unsigned long)p & 0xffffffff); |
| 389 |
while (envc-->0) { |
| 390 |
put_user(tswapl((target_ulong)p),envp++); |
| 391 |
while (get_user(p++)) /* nothing */ ; |
| 392 |
} |
| 393 |
put_user(0,envp);
|
| 394 |
info->env_end = (unsigned int)((unsigned long)p & 0xffffffff); |
| 395 |
return sp;
|
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} |
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|
| 398 |
|
| 399 |
|
| 400 |
static unsigned long load_elf_interp(struct elfhdr * interp_elf_ex, |
| 401 |
int interpreter_fd,
|
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unsigned long *interp_load_addr) |
| 403 |
{
|
| 404 |
struct elf_phdr *elf_phdata = NULL; |
| 405 |
struct elf_phdr *eppnt;
|
| 406 |
unsigned long load_addr; |
| 407 |
int load_addr_set = 0; |
| 408 |
int retval;
|
| 409 |
unsigned long last_bss, elf_bss; |
| 410 |
unsigned long error; |
| 411 |
int i;
|
| 412 |
|
| 413 |
elf_bss = 0;
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| 414 |
last_bss = 0;
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| 415 |
error = 0;
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| 416 |
|
| 417 |
/* We put this here so that mmap will search for the *first*
|
| 418 |
* available memory...
|
| 419 |
*/
|
| 420 |
load_addr = INTERP_LOADADDR; |
| 421 |
|
| 422 |
/* First of all, some simple consistency checks */
|
| 423 |
if ((interp_elf_ex->e_type != ET_EXEC &&
|
| 424 |
interp_elf_ex->e_type != ET_DYN) || |
| 425 |
!elf_check_arch(interp_elf_ex->e_machine)) {
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| 426 |
return ~0UL; |
| 427 |
} |
| 428 |
|
| 429 |
/* Now read in all of the header information */
|
| 430 |
|
| 431 |
if (sizeof(struct elf_phdr) * interp_elf_ex->e_phnum > X86_PAGE_SIZE) |
| 432 |
return ~0UL; |
| 433 |
|
| 434 |
elf_phdata = (struct elf_phdr *)
|
| 435 |
malloc(sizeof(struct elf_phdr) * interp_elf_ex->e_phnum); |
| 436 |
|
| 437 |
if (!elf_phdata)
|
| 438 |
return ~0UL; |
| 439 |
|
| 440 |
/*
|
| 441 |
* If the size of this structure has changed, then punt, since
|
| 442 |
* we will be doing the wrong thing.
|
| 443 |
*/
|
| 444 |
if (interp_elf_ex->e_phentsize != sizeof(struct elf_phdr)) |
| 445 |
{
|
| 446 |
free(elf_phdata); |
| 447 |
return ~0UL; |
| 448 |
} |
| 449 |
|
| 450 |
retval = lseek(interpreter_fd, interp_elf_ex->e_phoff, SEEK_SET); |
| 451 |
if(retval >= 0) { |
| 452 |
retval = read(interpreter_fd, |
| 453 |
(char *) elf_phdata,
|
| 454 |
sizeof(struct elf_phdr) * interp_elf_ex->e_phnum); |
| 455 |
} |
| 456 |
|
| 457 |
if (retval < 0) { |
| 458 |
perror("load_elf_interp");
|
| 459 |
exit(-1);
|
| 460 |
free (elf_phdata); |
| 461 |
return retval;
|
| 462 |
} |
| 463 |
#ifdef BSWAP_NEEDED
|
| 464 |
eppnt = elf_phdata; |
| 465 |
for (i=0; i<interp_elf_ex->e_phnum; i++, eppnt++) { |
| 466 |
bswap_phdr(eppnt); |
| 467 |
} |
| 468 |
#endif
|
| 469 |
eppnt = elf_phdata; |
| 470 |
for(i=0; i<interp_elf_ex->e_phnum; i++, eppnt++) |
| 471 |
if (eppnt->p_type == PT_LOAD) {
|
| 472 |
int elf_type = MAP_PRIVATE | MAP_DENYWRITE;
|
| 473 |
int elf_prot = 0; |
| 474 |
unsigned long vaddr = 0; |
| 475 |
unsigned long k; |
| 476 |
|
| 477 |
if (eppnt->p_flags & PF_R) elf_prot = PROT_READ;
|
| 478 |
if (eppnt->p_flags & PF_W) elf_prot |= PROT_WRITE;
|
| 479 |
if (eppnt->p_flags & PF_X) elf_prot |= PROT_EXEC;
|
| 480 |
if (interp_elf_ex->e_type == ET_EXEC || load_addr_set) {
|
| 481 |
elf_type |= MAP_FIXED; |
| 482 |
vaddr = eppnt->p_vaddr; |
| 483 |
} |
| 484 |
error = (unsigned long)mmap4k(load_addr+X86_ELF_PAGESTART(vaddr), |
| 485 |
eppnt->p_filesz + X86_ELF_PAGEOFFSET(eppnt->p_vaddr), |
| 486 |
elf_prot, |
| 487 |
elf_type, |
| 488 |
interpreter_fd, |
| 489 |
eppnt->p_offset - X86_ELF_PAGEOFFSET(eppnt->p_vaddr)); |
| 490 |
|
| 491 |
if (error > -1024UL) { |
| 492 |
/* Real error */
|
| 493 |
close(interpreter_fd); |
| 494 |
free(elf_phdata); |
| 495 |
return ~0UL; |
| 496 |
} |
| 497 |
|
| 498 |
if (!load_addr_set && interp_elf_ex->e_type == ET_DYN) {
|
| 499 |
load_addr = error; |
| 500 |
load_addr_set = 1;
|
| 501 |
} |
| 502 |
|
| 503 |
/*
|
| 504 |
* Find the end of the file mapping for this phdr, and keep
|
| 505 |
* track of the largest address we see for this.
|
| 506 |
*/
|
| 507 |
k = load_addr + eppnt->p_vaddr + eppnt->p_filesz; |
| 508 |
if (k > elf_bss) elf_bss = k;
|
| 509 |
|
| 510 |
/*
|
| 511 |
* Do the same thing for the memory mapping - between
|
| 512 |
* elf_bss and last_bss is the bss section.
|
| 513 |
*/
|
| 514 |
k = load_addr + eppnt->p_memsz + eppnt->p_vaddr; |
| 515 |
if (k > last_bss) last_bss = k;
|
| 516 |
} |
| 517 |
|
| 518 |
/* Now use mmap to map the library into memory. */
|
| 519 |
|
| 520 |
close(interpreter_fd); |
| 521 |
|
| 522 |
/*
|
| 523 |
* Now fill out the bss section. First pad the last page up
|
| 524 |
* to the page boundary, and then perform a mmap to make sure
|
| 525 |
* that there are zeromapped pages up to and including the last
|
| 526 |
* bss page.
|
| 527 |
*/
|
| 528 |
padzero(elf_bss); |
| 529 |
elf_bss = X86_ELF_PAGESTART(elf_bss + ALPHA_PAGE_SIZE - 1); /* What we have mapped so far */ |
| 530 |
|
| 531 |
/* Map the last of the bss segment */
|
| 532 |
if (last_bss > elf_bss) {
|
| 533 |
mmap4k(elf_bss, last_bss-elf_bss, |
| 534 |
PROT_READ|PROT_WRITE|PROT_EXEC, |
| 535 |
MAP_FIXED|MAP_PRIVATE|MAP_ANONYMOUS, -1, 0); |
| 536 |
} |
| 537 |
free(elf_phdata); |
| 538 |
|
| 539 |
*interp_load_addr = load_addr; |
| 540 |
return ((unsigned long) interp_elf_ex->e_entry) + load_addr; |
| 541 |
} |
| 542 |
|
| 543 |
|
| 544 |
|
| 545 |
static int load_elf_binary(struct linux_binprm * bprm, struct target_pt_regs * regs, |
| 546 |
struct image_info * info)
|
| 547 |
{
|
| 548 |
struct elfhdr elf_ex;
|
| 549 |
struct elfhdr interp_elf_ex;
|
| 550 |
struct exec interp_ex;
|
| 551 |
int interpreter_fd = -1; /* avoid warning */ |
| 552 |
unsigned long load_addr; |
| 553 |
int load_addr_set = 0; |
| 554 |
unsigned int interpreter_type = INTERPRETER_NONE; |
| 555 |
unsigned char ibcs2_interpreter; |
| 556 |
int i;
|
| 557 |
void * mapped_addr;
|
| 558 |
struct elf_phdr * elf_ppnt;
|
| 559 |
struct elf_phdr *elf_phdata;
|
| 560 |
unsigned long elf_bss, k, elf_brk; |
| 561 |
int retval;
|
| 562 |
char * elf_interpreter;
|
| 563 |
unsigned long elf_entry, interp_load_addr = 0; |
| 564 |
int status;
|
| 565 |
unsigned long start_code, end_code, end_data; |
| 566 |
unsigned long elf_stack; |
| 567 |
char passed_fileno[6]; |
| 568 |
|
| 569 |
ibcs2_interpreter = 0;
|
| 570 |
status = 0;
|
| 571 |
load_addr = 0;
|
| 572 |
elf_ex = *((struct elfhdr *) bprm->buf); /* exec-header */ |
| 573 |
#ifdef BSWAP_NEEDED
|
| 574 |
bswap_ehdr(&elf_ex); |
| 575 |
#endif
|
| 576 |
|
| 577 |
if (elf_ex.e_ident[0] != 0x7f || |
| 578 |
strncmp(&elf_ex.e_ident[1], "ELF",3) != 0) { |
| 579 |
return -ENOEXEC;
|
| 580 |
} |
| 581 |
|
| 582 |
/* First of all, some simple consistency checks */
|
| 583 |
if ((elf_ex.e_type != ET_EXEC && elf_ex.e_type != ET_DYN) ||
|
| 584 |
(! elf_check_arch(elf_ex.e_machine))) {
|
| 585 |
return -ENOEXEC;
|
| 586 |
} |
| 587 |
|
| 588 |
/* Now read in all of the header information */
|
| 589 |
|
| 590 |
elf_phdata = (struct elf_phdr *)malloc(elf_ex.e_phentsize*elf_ex.e_phnum);
|
| 591 |
if (elf_phdata == NULL) { |
| 592 |
return -ENOMEM;
|
| 593 |
} |
| 594 |
|
| 595 |
retval = lseek(bprm->fd, elf_ex.e_phoff, SEEK_SET); |
| 596 |
if(retval > 0) { |
| 597 |
retval = read(bprm->fd, (char *) elf_phdata,
|
| 598 |
elf_ex.e_phentsize * elf_ex.e_phnum); |
| 599 |
} |
| 600 |
|
| 601 |
if (retval < 0) { |
| 602 |
perror("load_elf_binary");
|
| 603 |
exit(-1);
|
| 604 |
free (elf_phdata); |
| 605 |
return -errno;
|
| 606 |
} |
| 607 |
|
| 608 |
#ifdef BSWAP_NEEDED
|
| 609 |
elf_ppnt = elf_phdata; |
| 610 |
for (i=0; i<elf_ex.e_phnum; i++, elf_ppnt++) { |
| 611 |
bswap_phdr(elf_ppnt); |
| 612 |
} |
| 613 |
#endif
|
| 614 |
elf_ppnt = elf_phdata; |
| 615 |
|
| 616 |
elf_bss = 0;
|
| 617 |
elf_brk = 0;
|
| 618 |
|
| 619 |
|
| 620 |
elf_stack = ~0UL;
|
| 621 |
elf_interpreter = NULL;
|
| 622 |
start_code = ~0UL;
|
| 623 |
end_code = 0;
|
| 624 |
end_data = 0;
|
| 625 |
|
| 626 |
for(i=0;i < elf_ex.e_phnum; i++) { |
| 627 |
if (elf_ppnt->p_type == PT_INTERP) {
|
| 628 |
if ( elf_interpreter != NULL ) |
| 629 |
{
|
| 630 |
free (elf_phdata); |
| 631 |
free(elf_interpreter); |
| 632 |
close(bprm->fd); |
| 633 |
return -EINVAL;
|
| 634 |
} |
| 635 |
|
| 636 |
/* This is the program interpreter used for
|
| 637 |
* shared libraries - for now assume that this
|
| 638 |
* is an a.out format binary
|
| 639 |
*/
|
| 640 |
|
| 641 |
elf_interpreter = (char *)malloc(elf_ppnt->p_filesz+strlen(X86_DEFAULT_LIB_DIR));
|
| 642 |
|
| 643 |
if (elf_interpreter == NULL) { |
| 644 |
free (elf_phdata); |
| 645 |
close(bprm->fd); |
| 646 |
return -ENOMEM;
|
| 647 |
} |
| 648 |
|
| 649 |
strcpy(elf_interpreter, X86_DEFAULT_LIB_DIR); |
| 650 |
retval = lseek(bprm->fd, elf_ppnt->p_offset, SEEK_SET); |
| 651 |
if(retval >= 0) { |
| 652 |
retval = read(bprm->fd, |
| 653 |
elf_interpreter+strlen(X86_DEFAULT_LIB_DIR), |
| 654 |
elf_ppnt->p_filesz); |
| 655 |
} |
| 656 |
if(retval < 0) { |
| 657 |
perror("load_elf_binary2");
|
| 658 |
exit(-1);
|
| 659 |
} |
| 660 |
|
| 661 |
/* If the program interpreter is one of these two,
|
| 662 |
then assume an iBCS2 image. Otherwise assume
|
| 663 |
a native linux image. */
|
| 664 |
|
| 665 |
/* JRP - Need to add X86 lib dir stuff here... */
|
| 666 |
|
| 667 |
if (strcmp(elf_interpreter,"/usr/lib/libc.so.1") == 0 || |
| 668 |
strcmp(elf_interpreter,"/usr/lib/ld.so.1") == 0) { |
| 669 |
ibcs2_interpreter = 1;
|
| 670 |
} |
| 671 |
|
| 672 |
#if 0
|
| 673 |
printf("Using ELF interpreter %s\n", elf_interpreter);
|
| 674 |
#endif
|
| 675 |
if (retval >= 0) { |
| 676 |
retval = open(elf_interpreter, O_RDONLY); |
| 677 |
if(retval >= 0) { |
| 678 |
interpreter_fd = retval; |
| 679 |
} |
| 680 |
else {
|
| 681 |
perror(elf_interpreter); |
| 682 |
exit(-1);
|
| 683 |
/* retval = -errno; */
|
| 684 |
} |
| 685 |
} |
| 686 |
|
| 687 |
if (retval >= 0) { |
| 688 |
retval = lseek(interpreter_fd, 0, SEEK_SET);
|
| 689 |
if(retval >= 0) { |
| 690 |
retval = read(interpreter_fd,bprm->buf,128);
|
| 691 |
} |
| 692 |
} |
| 693 |
if (retval >= 0) { |
| 694 |
interp_ex = *((struct exec *) bprm->buf); /* aout exec-header */ |
| 695 |
interp_elf_ex=*((struct elfhdr *) bprm->buf); /* elf exec-header */ |
| 696 |
} |
| 697 |
if (retval < 0) { |
| 698 |
perror("load_elf_binary3");
|
| 699 |
exit(-1);
|
| 700 |
free (elf_phdata); |
| 701 |
free(elf_interpreter); |
| 702 |
close(bprm->fd); |
| 703 |
return retval;
|
| 704 |
} |
| 705 |
} |
| 706 |
elf_ppnt++; |
| 707 |
} |
| 708 |
|
| 709 |
/* Some simple consistency checks for the interpreter */
|
| 710 |
if (elf_interpreter){
|
| 711 |
interpreter_type = INTERPRETER_ELF | INTERPRETER_AOUT; |
| 712 |
|
| 713 |
/* Now figure out which format our binary is */
|
| 714 |
if ((N_MAGIC(interp_ex) != OMAGIC) && (N_MAGIC(interp_ex) != ZMAGIC) &&
|
| 715 |
(N_MAGIC(interp_ex) != QMAGIC)) {
|
| 716 |
interpreter_type = INTERPRETER_ELF; |
| 717 |
} |
| 718 |
|
| 719 |
if (interp_elf_ex.e_ident[0] != 0x7f || |
| 720 |
strncmp(&interp_elf_ex.e_ident[1], "ELF",3) != 0) { |
| 721 |
interpreter_type &= ~INTERPRETER_ELF; |
| 722 |
} |
| 723 |
|
| 724 |
if (!interpreter_type) {
|
| 725 |
free(elf_interpreter); |
| 726 |
free(elf_phdata); |
| 727 |
close(bprm->fd); |
| 728 |
return -ELIBBAD;
|
| 729 |
} |
| 730 |
} |
| 731 |
|
| 732 |
/* OK, we are done with that, now set up the arg stuff,
|
| 733 |
and then start this sucker up */
|
| 734 |
|
| 735 |
if (!bprm->sh_bang) {
|
| 736 |
char * passed_p;
|
| 737 |
|
| 738 |
if (interpreter_type == INTERPRETER_AOUT) {
|
| 739 |
sprintf(passed_fileno, "%d", bprm->fd);
|
| 740 |
passed_p = passed_fileno; |
| 741 |
|
| 742 |
if (elf_interpreter) {
|
| 743 |
bprm->p = copy_strings(1,&passed_p,bprm->page,bprm->p);
|
| 744 |
bprm->argc++; |
| 745 |
} |
| 746 |
} |
| 747 |
if (!bprm->p) {
|
| 748 |
if (elf_interpreter) {
|
| 749 |
free(elf_interpreter); |
| 750 |
} |
| 751 |
free (elf_phdata); |
| 752 |
close(bprm->fd); |
| 753 |
return -E2BIG;
|
| 754 |
} |
| 755 |
} |
| 756 |
|
| 757 |
/* OK, This is the point of no return */
|
| 758 |
info->end_data = 0;
|
| 759 |
info->end_code = 0;
|
| 760 |
info->start_mmap = (unsigned long)ELF_START_MMAP; |
| 761 |
info->mmap = 0;
|
| 762 |
elf_entry = (unsigned long) elf_ex.e_entry; |
| 763 |
|
| 764 |
/* Do this so that we can load the interpreter, if need be. We will
|
| 765 |
change some of these later */
|
| 766 |
info->rss = 0;
|
| 767 |
bprm->p = setup_arg_pages(bprm->p, bprm, info); |
| 768 |
info->start_stack = bprm->p; |
| 769 |
|
| 770 |
/* Now we do a little grungy work by mmaping the ELF image into
|
| 771 |
* the correct location in memory. At this point, we assume that
|
| 772 |
* the image should be loaded at fixed address, not at a variable
|
| 773 |
* address.
|
| 774 |
*/
|
| 775 |
|
| 776 |
|
| 777 |
|
| 778 |
for(i = 0, elf_ppnt = elf_phdata; i < elf_ex.e_phnum; i++, elf_ppnt++) { |
| 779 |
if (elf_ppnt->p_type == PT_LOAD) {
|
| 780 |
int elf_prot = 0; |
| 781 |
if (elf_ppnt->p_flags & PF_R) elf_prot |= PROT_READ;
|
| 782 |
if (elf_ppnt->p_flags & PF_W) elf_prot |= PROT_WRITE;
|
| 783 |
if (elf_ppnt->p_flags & PF_X) elf_prot |= PROT_EXEC;
|
| 784 |
|
| 785 |
mapped_addr = mmap4k(X86_ELF_PAGESTART(elf_ppnt->p_vaddr), |
| 786 |
(elf_ppnt->p_filesz + |
| 787 |
X86_ELF_PAGEOFFSET(elf_ppnt->p_vaddr)), |
| 788 |
elf_prot, |
| 789 |
(MAP_FIXED | MAP_PRIVATE | MAP_DENYWRITE), |
| 790 |
bprm->fd, |
| 791 |
(elf_ppnt->p_offset - |
| 792 |
X86_ELF_PAGEOFFSET(elf_ppnt->p_vaddr))); |
| 793 |
|
| 794 |
if((unsigned long)mapped_addr == 0xffffffffffffffff) { |
| 795 |
perror("mmap");
|
| 796 |
exit(-1);
|
| 797 |
} |
| 798 |
|
| 799 |
|
| 800 |
|
| 801 |
#ifdef LOW_ELF_STACK
|
| 802 |
if (X86_ELF_PAGESTART(elf_ppnt->p_vaddr) < elf_stack)
|
| 803 |
elf_stack = X86_ELF_PAGESTART(elf_ppnt->p_vaddr); |
| 804 |
#endif
|
| 805 |
|
| 806 |
if (!load_addr_set) {
|
| 807 |
load_addr = elf_ppnt->p_vaddr - elf_ppnt->p_offset; |
| 808 |
load_addr_set = 1;
|
| 809 |
} |
| 810 |
k = elf_ppnt->p_vaddr; |
| 811 |
if (k < start_code) start_code = k;
|
| 812 |
k = elf_ppnt->p_vaddr + elf_ppnt->p_filesz; |
| 813 |
if (k > elf_bss) elf_bss = k;
|
| 814 |
#if 1 |
| 815 |
if ((elf_ppnt->p_flags & PF_X) && end_code < k)
|
| 816 |
#else
|
| 817 |
if ( !(elf_ppnt->p_flags & PF_W) && end_code < k)
|
| 818 |
#endif
|
| 819 |
end_code = k; |
| 820 |
if (end_data < k) end_data = k;
|
| 821 |
k = elf_ppnt->p_vaddr + elf_ppnt->p_memsz; |
| 822 |
if (k > elf_brk) elf_brk = k;
|
| 823 |
} |
| 824 |
} |
| 825 |
|
| 826 |
if (elf_interpreter) {
|
| 827 |
if (interpreter_type & 1) { |
| 828 |
elf_entry = load_aout_interp(&interp_ex, interpreter_fd); |
| 829 |
} |
| 830 |
else if (interpreter_type & 2) { |
| 831 |
elf_entry = load_elf_interp(&interp_elf_ex, interpreter_fd, |
| 832 |
&interp_load_addr); |
| 833 |
} |
| 834 |
|
| 835 |
close(interpreter_fd); |
| 836 |
free(elf_interpreter); |
| 837 |
|
| 838 |
if (elf_entry == ~0UL) { |
| 839 |
printf("Unable to load interpreter\n");
|
| 840 |
free(elf_phdata); |
| 841 |
exit(-1);
|
| 842 |
return 0; |
| 843 |
} |
| 844 |
} |
| 845 |
|
| 846 |
free(elf_phdata); |
| 847 |
|
| 848 |
if (interpreter_type != INTERPRETER_AOUT) close(bprm->fd);
|
| 849 |
info->personality = (ibcs2_interpreter ? PER_SVR4 : PER_LINUX); |
| 850 |
|
| 851 |
#ifdef LOW_ELF_STACK
|
| 852 |
info->start_stack = bprm->p = elf_stack - 4;
|
| 853 |
#endif
|
| 854 |
bprm->p = (unsigned long) |
| 855 |
create_elf_tables((char *)bprm->p,
|
| 856 |
bprm->argc, |
| 857 |
bprm->envc, |
| 858 |
(interpreter_type == INTERPRETER_ELF ? &elf_ex : NULL),
|
| 859 |
load_addr, |
| 860 |
interp_load_addr, |
| 861 |
(interpreter_type == INTERPRETER_AOUT ? 0 : 1), |
| 862 |
info); |
| 863 |
if (interpreter_type == INTERPRETER_AOUT)
|
| 864 |
info->arg_start += strlen(passed_fileno) + 1;
|
| 865 |
info->start_brk = info->brk = elf_brk; |
| 866 |
info->end_code = end_code; |
| 867 |
info->start_code = start_code; |
| 868 |
info->end_data = end_data; |
| 869 |
info->start_stack = bprm->p; |
| 870 |
|
| 871 |
/* Calling set_brk effectively mmaps the pages that we need for the bss and break
|
| 872 |
sections */
|
| 873 |
set_brk(elf_bss, elf_brk); |
| 874 |
|
| 875 |
padzero(elf_bss); |
| 876 |
|
| 877 |
#if 0
|
| 878 |
printf("(start_brk) %x\n" , info->start_brk);
|
| 879 |
printf("(end_code) %x\n" , info->end_code);
|
| 880 |
printf("(start_code) %x\n" , info->start_code);
|
| 881 |
printf("(end_data) %x\n" , info->end_data);
|
| 882 |
printf("(start_stack) %x\n" , info->start_stack);
|
| 883 |
printf("(brk) %x\n" , info->brk);
|
| 884 |
#endif
|
| 885 |
|
| 886 |
if ( info->personality == PER_SVR4 )
|
| 887 |
{
|
| 888 |
/* Why this, you ask??? Well SVr4 maps page 0 as read-only,
|
| 889 |
and some applications "depend" upon this behavior.
|
| 890 |
Since we do not have the power to recompile these, we
|
| 891 |
emulate the SVr4 behavior. Sigh. */
|
| 892 |
mapped_addr = mmap4k(NULL, ALPHA_PAGE_SIZE, PROT_READ | PROT_EXEC,
|
| 893 |
MAP_FIXED | MAP_PRIVATE, -1, 0); |
| 894 |
} |
| 895 |
|
| 896 |
#ifdef ELF_PLAT_INIT
|
| 897 |
/*
|
| 898 |
* The ABI may specify that certain registers be set up in special
|
| 899 |
* ways (on i386 %edx is the address of a DT_FINI function, for
|
| 900 |
* example. This macro performs whatever initialization to
|
| 901 |
* the regs structure is required.
|
| 902 |
*/
|
| 903 |
ELF_PLAT_INIT(regs); |
| 904 |
#endif
|
| 905 |
|
| 906 |
|
| 907 |
info->entry = elf_entry; |
| 908 |
|
| 909 |
return 0; |
| 910 |
} |
| 911 |
|
| 912 |
|
| 913 |
|
| 914 |
int elf_exec(const char * filename, char ** argv, char ** envp, |
| 915 |
struct target_pt_regs * regs, struct image_info *infop) |
| 916 |
{
|
| 917 |
struct linux_binprm bprm;
|
| 918 |
int retval;
|
| 919 |
int i;
|
| 920 |
|
| 921 |
bprm.p = X86_PAGE_SIZE*MAX_ARG_PAGES-sizeof(unsigned int); |
| 922 |
for (i=0 ; i<MAX_ARG_PAGES ; i++) /* clear page-table */ |
| 923 |
bprm.page[i] = 0;
|
| 924 |
retval = open(filename, O_RDONLY); |
| 925 |
if (retval == -1) { |
| 926 |
perror(filename); |
| 927 |
exit(-1);
|
| 928 |
/* return retval; */
|
| 929 |
} |
| 930 |
else {
|
| 931 |
bprm.fd = retval; |
| 932 |
} |
| 933 |
bprm.filename = (char *)filename;
|
| 934 |
bprm.sh_bang = 0;
|
| 935 |
bprm.loader = 0;
|
| 936 |
bprm.exec = 0;
|
| 937 |
bprm.dont_iput = 0;
|
| 938 |
bprm.argc = count(argv); |
| 939 |
bprm.envc = count(envp); |
| 940 |
|
| 941 |
retval = prepare_binprm(&bprm); |
| 942 |
|
| 943 |
if(retval>=0) { |
| 944 |
bprm.p = copy_strings(1, &bprm.filename, bprm.page, bprm.p);
|
| 945 |
bprm.exec = bprm.p; |
| 946 |
bprm.p = copy_strings(bprm.envc,envp,bprm.page,bprm.p); |
| 947 |
bprm.p = copy_strings(bprm.argc,argv,bprm.page,bprm.p); |
| 948 |
if (!bprm.p) {
|
| 949 |
retval = -E2BIG; |
| 950 |
} |
| 951 |
} |
| 952 |
|
| 953 |
if(retval>=0) { |
| 954 |
retval = load_elf_binary(&bprm,regs,infop); |
| 955 |
} |
| 956 |
if(retval>=0) { |
| 957 |
/* success. Initialize important registers */
|
| 958 |
regs->esp = infop->start_stack; |
| 959 |
regs->eip = infop->entry; |
| 960 |
return retval;
|
| 961 |
} |
| 962 |
|
| 963 |
/* Something went wrong, return the inode and free the argument pages*/
|
| 964 |
for (i=0 ; i<MAX_ARG_PAGES ; i++) { |
| 965 |
free_page((void *)bprm.page[i]);
|
| 966 |
} |
| 967 |
return(retval);
|
| 968 |
} |
| 969 |
|
| 970 |
|
| 971 |
static int load_aout_interp(void * exptr, int interp_fd) |
| 972 |
{
|
| 973 |
printf("a.out interpreter not yet supported\n");
|
| 974 |
return(0); |
| 975 |
} |
| 976 |
|