Пример #1
0
/* do_obreak() must return target errnos. */
static abi_long do_obreak(abi_ulong new_brk)
{
    abi_ulong brk_page;
    abi_long mapped_addr;
    int new_alloc_size;

    if (!new_brk)
        return 0;
    if (new_brk < target_original_brk)
        return -TARGET_EINVAL;

    brk_page = HOST_PAGE_ALIGN(target_brk);

    /* If the new brk is less than this, set it and we're done... */
    if (new_brk < brk_page) {
        target_brk = new_brk;
        return 0;
    }

    /* We need to allocate more memory after the brk... */
    new_alloc_size = HOST_PAGE_ALIGN(new_brk - brk_page + 1);
    mapped_addr = get_errno(target_mmap(brk_page, new_alloc_size,
                                        PROT_READ|PROT_WRITE,
                                        MAP_ANON|MAP_FIXED|MAP_PRIVATE, -1, 0));

    if (!is_error(mapped_addr))
        target_brk = new_brk;
    else
        return mapped_addr;

    return 0;
}
Пример #2
0
static void set_brk(abi_ulong start, abi_ulong end)
{
	/* page-align the start and end addresses... */
        start = HOST_PAGE_ALIGN(start);
        end = HOST_PAGE_ALIGN(end);
        if (end <= start)
                return;
        if(target_mmap(start, end - start,
                       PROT_READ | PROT_WRITE | PROT_EXEC,
                       MAP_FIXED | MAP_PRIVATE | MAP_ANONYMOUS, -1, 0) == -1) {
	    perror("cannot mmap brk");
	    exit(-1);
	}
}
Пример #3
0
/* We need to explicitly zero any fractional pages after the data
   section (i.e. bss).  This would contain the junk from the file that
   should not be in memory. */
static void padzero(abi_ulong elf_bss, abi_ulong last_bss)
{
        abi_ulong nbyte;

	if (elf_bss >= last_bss)
		return;

        /* XXX: this is really a hack : if the real host page size is
           smaller than the target page size, some pages after the end
           of the file may not be mapped. A better fix would be to
           patch target_mmap(), but it is more complicated as the file
           size must be known */
        if (qemu_real_host_page_size < qemu_host_page_size) {
            abi_ulong end_addr, end_addr1;
            end_addr1 = (elf_bss + qemu_real_host_page_size - 1) &
                ~(qemu_real_host_page_size - 1);
            end_addr = HOST_PAGE_ALIGN(elf_bss);
            if (end_addr1 < end_addr) {
                mmap((void *)g2h(end_addr1), end_addr - end_addr1,
                     PROT_READ|PROT_WRITE|PROT_EXEC,
                     MAP_FIXED|MAP_PRIVATE|MAP_ANONYMOUS, -1, 0);
            }
        }

        nbyte = elf_bss & (qemu_host_page_size-1);
        if (nbyte) {
	    nbyte = qemu_host_page_size - nbyte;
	    do {
                /* FIXME - what to do if put_user() fails? */
		put_user_u8(0, elf_bss);
                elf_bss++;
	    } while (--nbyte);
        }
}
Пример #4
0
int target_munmap(abi_ulong start, abi_ulong len)
{
    abi_ulong end, real_start, real_end, addr;
    int prot, ret;

#ifdef DEBUG_MMAP
    printf("munmap: start=0x" TARGET_ABI_FMT_lx " len=0x"
           TARGET_ABI_FMT_lx "\n",
           start, len);
#endif
    if (start & ~TARGET_PAGE_MASK)
        return -EINVAL;
    len = TARGET_PAGE_ALIGN(len);
    if (len == 0)
        return -EINVAL;
    mmap_lock();
    end = start + len;
    real_start = start & qemu_host_page_mask;
    real_end = HOST_PAGE_ALIGN(end);

    if (start > real_start) {
        /* handle host page containing start */
        prot = 0;
        for(addr = real_start; addr < start; addr += TARGET_PAGE_SIZE) {
            prot |= page_get_flags(addr);
        }
        if (real_end == real_start + qemu_host_page_size) {
            for(addr = end; addr < real_end; addr += TARGET_PAGE_SIZE) {
                prot |= page_get_flags(addr);
            }
            end = real_end;
        }
        if (prot != 0)
            real_start += qemu_host_page_size;
    }
    if (end < real_end) {
        prot = 0;
        for(addr = end; addr < real_end; addr += TARGET_PAGE_SIZE) {
            prot |= page_get_flags(addr);
        }
        if (prot != 0)
            real_end -= qemu_host_page_size;
    }

    ret = 0;
    /* unmap what we can */
    if (real_start < real_end) {
        if (RESERVED_VA) {
            mmap_reserve(real_start, real_end - real_start);
        } else {
            ret = munmap(g2h(real_start), real_end - real_start);
        }
    }

    if (ret == 0)
        page_set_flags(start, start + len, 0);
    mmap_unlock();
    return ret;
}
Пример #5
0
/*
 * Find and reserve a free memory area of size 'size'. The search
 * starts at 'start'.
 * It must be called with mmap_lock() held.
 * Return -1 if error.
 */
abi_ulong mmap_find_vma(abi_ulong start, abi_ulong size)
{
    void *ptr;
    abi_ulong addr;

    size = HOST_PAGE_ALIGN(size);
    start &= qemu_host_page_mask;

    /* If 'start' == 0, then a default start address is used. */
    if (start == 0)
        start = mmap_next_start;

    addr = start;

    for(;;) {
        /*
         * Reserve needed memory area to avoid a race.
         * It should be discarded using:
         *  - mmap() with MAP_FIXED flag
         *  - mremap() with MREMAP_FIXED flag
         *  - shmat() with SHM_REMAP flag
         */
        ptr = mmap((void *)(unsigned long)addr, size, PROT_NONE,
                   MAP_ANONYMOUS|MAP_PRIVATE|MAP_NORESERVE, -1, 0);

        /* ENOMEM, if host address space has no memory */
        if (ptr == MAP_FAILED)
            return (abi_ulong)-1;

        /* If address fits target address space we've found what we need */
        if ((unsigned long)ptr + size - 1 <= (abi_ulong)-1)
            break;

        /* Unmap and try again with new page */
        munmap(ptr, size);
        addr += qemu_host_page_size;

        /* ENOMEM if we check whole of target address space */
        if (addr == start)
            return (abi_ulong)-1;
    }

    /* Update default start address */
    if (start == mmap_next_start)
        mmap_next_start = (unsigned long)ptr + size;

    return h2g(ptr);
}
Пример #6
0
/* Subroutine of mmap_find_vma, used when we have pre-allocated a chunk
   of guest address space.  */
static abi_ulong mmap_find_vma_reserved(abi_ulong start, abi_ulong size)
{
    abi_ulong addr;
    abi_ulong end_addr;
    int prot;
    int looped = 0;

    if (size > RESERVED_VA) {
        return (abi_ulong)-1;
    }

    size = HOST_PAGE_ALIGN(size);
    end_addr = start + size;
    if (end_addr > RESERVED_VA) {
        end_addr = RESERVED_VA;
    }
    addr = end_addr - qemu_host_page_size;

    while (1) {
        if (addr > end_addr) {
            if (looped) {
                return (abi_ulong)-1;
            }
            end_addr = RESERVED_VA;
            addr = end_addr - qemu_host_page_size;
            looped = 1;
            continue;
        }
        prot = page_get_flags(addr);
        if (prot) {
            end_addr = addr;
        }
        if (addr + size == end_addr) {
            break;
        }
        addr -= qemu_host_page_size;
    }

    if (start == mmap_next_start) {
        mmap_next_start = addr;
    }

    return addr;
}
Пример #7
0
/* page_init() marks pages used by the host as reserved to be sure not
   to use them. */
static abi_ulong mmap_find_vma(abi_ulong start, abi_ulong size)
{
    abi_ulong addr, addr1, addr_start;
    int prot;
    unsigned long new_brk;

    new_brk = (unsigned long)sbrk(0);
    if (last_brk && last_brk < new_brk && last_brk == (target_ulong)last_brk) {
        /* This is a hack to catch the host allocating memory with brk().
           If it uses mmap then we loose.
           FIXME: We really want to avoid the host allocating memory in
           the first place, and maybe leave some slack to avoid switching
           to mmap.  */
        page_set_flags(last_brk & TARGET_PAGE_MASK,
                       TARGET_PAGE_ALIGN(new_brk),
                       PAGE_RESERVED); 
    }
    last_brk = new_brk;

    size = HOST_PAGE_ALIGN(size);
    start = start & qemu_host_page_mask;
    addr = start;
    if (addr == 0)
        addr = mmap_next_start;
    addr_start = addr;
    for(;;) {
        prot = 0;
        for(addr1 = addr; addr1 < (addr + size); addr1 += TARGET_PAGE_SIZE) {
            prot |= page_get_flags(addr1);
        }
        if (prot == 0)
            break;
        addr += qemu_host_page_size;
        /* we found nothing */
        if (addr == addr_start)
            return (abi_ulong)-1;
    }
    if (start == 0)
        mmap_next_start = addr + size;
    return addr;
}
Пример #8
0
static void mmap_reserve(abi_ulong start, abi_ulong size)
{
    abi_ulong real_start;
    abi_ulong real_end;
    abi_ulong addr;
    abi_ulong end;
    int prot;

    real_start = start & qemu_host_page_mask;
    real_end = HOST_PAGE_ALIGN(start + size);
    end = start + size;
    if (start > real_start) {
        /* handle host page containing start */
        prot = 0;
        for (addr = real_start; addr < start; addr += TARGET_PAGE_SIZE) {
            prot |= page_get_flags(addr);
        }
        if (real_end == real_start + qemu_host_page_size) {
            for (addr = end; addr < real_end; addr += TARGET_PAGE_SIZE) {
                prot |= page_get_flags(addr);
            }
            end = real_end;
        }
        if (prot != 0)
            real_start += qemu_host_page_size;
    }
    if (end < real_end) {
        prot = 0;
        for (addr = end; addr < real_end; addr += TARGET_PAGE_SIZE) {
            prot |= page_get_flags(addr);
        }
        if (prot != 0)
            real_end -= qemu_host_page_size;
    }
    if (real_start != real_end) {
        mmap(g2h(real_start), real_end - real_start, PROT_NONE,
                 MAP_FIXED | MAP_ANONYMOUS | MAP_PRIVATE | MAP_NORESERVE,
                 -1, 0);
    }
}
Пример #9
0
/* NOTE: all the constants are the HOST ones */
abi_long target_mmap(abi_ulong start, abi_ulong len, int prot,
                     int flags, int fd, abi_ulong offset)
{
    abi_ulong ret, end, real_start, real_end, retaddr, host_offset, host_len;
    unsigned long host_start;

    mmap_lock();
#ifdef DEBUG_MMAP
    {
        printf("mmap: start=0x" TARGET_FMT_lx
               " len=0x" TARGET_FMT_lx " prot=%c%c%c flags=",
               start, len,
               prot & PROT_READ ? 'r' : '-',
               prot & PROT_WRITE ? 'w' : '-',
               prot & PROT_EXEC ? 'x' : '-');
        if (flags & MAP_FIXED)
            printf("MAP_FIXED ");
        if (flags & MAP_ANONYMOUS)
            printf("MAP_ANON ");
        switch(flags & MAP_TYPE) {
        case MAP_PRIVATE:
            printf("MAP_PRIVATE ");
            break;
        case MAP_SHARED:
            printf("MAP_SHARED ");
            break;
        default:
            printf("[MAP_TYPE=0x%x] ", flags & MAP_TYPE);
            break;
        }
        printf("fd=%d offset=" TARGET_FMT_lx "\n", fd, offset);
    }
#endif

    if (offset & ~TARGET_PAGE_MASK) {
        errno = EINVAL;
        goto fail;
    }

    len = TARGET_PAGE_ALIGN(len);
    if (len == 0)
        goto the_end;
    real_start = start & qemu_host_page_mask;

    if (!(flags & MAP_FIXED)) {
        abi_ulong mmap_start;
        void *p;
        host_offset = offset & qemu_host_page_mask;
        host_len = len + offset - host_offset;
        host_len = HOST_PAGE_ALIGN(host_len);
        mmap_start = mmap_find_vma(real_start, host_len);
        if (mmap_start == (abi_ulong)-1) {
            errno = ENOMEM;
            goto fail;
        }
        /* Note: we prefer to control the mapping address. It is
           especially important if qemu_host_page_size >
           qemu_real_host_page_size */
        p = mmap(g2h(mmap_start),
                 host_len, prot, flags | MAP_FIXED, fd, host_offset);
        if (p == MAP_FAILED)
            goto fail;
        /* update start so that it points to the file position at 'offset' */
        host_start = (unsigned long)p;
        if (!(flags & MAP_ANONYMOUS))
            host_start += offset - host_offset;
        start = h2g(host_start);
    } else {
        int flg;
        target_ulong addr;

        if (start & ~TARGET_PAGE_MASK) {
            errno = EINVAL;
            goto fail;
        }
        end = start + len;
        real_end = HOST_PAGE_ALIGN(end);

	/*
	 * Test if requested memory area fits target address space
	 * It can fail only on 64-bit host with 32-bit target.
	 * On any other target/host host mmap() handles this error correctly.
	 */
        if ((unsigned long)start + len - 1 > (abi_ulong) -1) {
            errno = EINVAL;
            goto fail;
        }

        for(addr = real_start; addr < real_end; addr += TARGET_PAGE_SIZE) {
            flg = page_get_flags(addr);
            if (flg & PAGE_RESERVED) {
                errno = ENXIO;
                goto fail;
            }
        }

        /* worst case: we cannot map the file because the offset is not
           aligned, so we read it */
        if (!(flags & MAP_ANONYMOUS) &&
            (offset & ~qemu_host_page_mask) != (start & ~qemu_host_page_mask)) {
            /* msync() won't work here, so we return an error if write is
               possible while it is a shared mapping */
            if ((flags & MAP_TYPE) == MAP_SHARED &&
                (prot & PROT_WRITE)) {
                errno = EINVAL;
                goto fail;
            }
            retaddr = target_mmap(start, len, prot | PROT_WRITE,
                                  MAP_FIXED | MAP_PRIVATE | MAP_ANONYMOUS,
                                  -1, 0);
            if (retaddr == -1)
                goto fail;
            pread(fd, g2h(start), len, offset);
            if (!(prot & PROT_WRITE)) {
                ret = target_mprotect(start, len, prot);
                if (ret != 0) {
                    start = ret;
                    goto the_end;
                }
            }
            goto the_end;
        }
        
        /* handle the start of the mapping */
        if (start > real_start) {
            if (real_end == real_start + qemu_host_page_size) {
                /* one single host page */
                ret = mmap_frag(real_start, start, end,
                                prot, flags, fd, offset);
                if (ret == -1)
                    goto fail;
                goto the_end1;
            }
            ret = mmap_frag(real_start, start, real_start + qemu_host_page_size,
                            prot, flags, fd, offset);
            if (ret == -1)
                goto fail;
            real_start += qemu_host_page_size;
        }
        /* handle the end of the mapping */
        if (end < real_end) {
            ret = mmap_frag(real_end - qemu_host_page_size,
                            real_end - qemu_host_page_size, real_end,
                            prot, flags, fd,
                            offset + real_end - qemu_host_page_size - start);
            if (ret == -1)
                goto fail;
            real_end -= qemu_host_page_size;
        }

        /* map the middle (easier) */
        if (real_start < real_end) {
            void *p;
            unsigned long offset1;
            if (flags & MAP_ANONYMOUS)
                offset1 = 0;
            else
                offset1 = offset + real_start - start;
            p = mmap(g2h(real_start), real_end - real_start,
                     prot, flags, fd, offset1);
            if (p == MAP_FAILED)
                goto fail;
        }
    }
 the_end1:
    page_set_flags(start, start + len, prot | PAGE_VALID);
 the_end:
#ifdef DEBUG_MMAP
    printf("ret=0x" TARGET_FMT_lx "\n", start);
    page_dump(stdout);
    printf("\n");
#endif
    mmap_unlock();
    return start;
fail:
    mmap_unlock();
    return -1;
}
Пример #10
0
/* NOTE: all the constants are the HOST ones, but addresses are target. */
int target_mprotect(abi_ulong start, abi_ulong len, int prot)
{
    abi_ulong end, host_start, host_end, addr;
    int prot1, ret;

#ifdef DEBUG_MMAP
    printf("mprotect: start=0x" TARGET_FMT_lx
           "len=0x" TARGET_FMT_lx " prot=%c%c%c\n", start, len,
           prot & PROT_READ ? 'r' : '-',
           prot & PROT_WRITE ? 'w' : '-',
           prot & PROT_EXEC ? 'x' : '-');
#endif

    if ((start & ~TARGET_PAGE_MASK) != 0)
        return -EINVAL;
    len = TARGET_PAGE_ALIGN(len);
    end = start + len;
    if (end < start)
        return -EINVAL;
    prot &= PROT_READ | PROT_WRITE | PROT_EXEC;
    if (len == 0)
        return 0;

    mmap_lock();
    host_start = start & qemu_host_page_mask;
    host_end = HOST_PAGE_ALIGN(end);
    if (start > host_start) {
        /* handle host page containing start */
        prot1 = prot;
        for(addr = host_start; addr < start; addr += TARGET_PAGE_SIZE) {
            prot1 |= page_get_flags(addr);
        }
        if (host_end == host_start + qemu_host_page_size) {
            for(addr = end; addr < host_end; addr += TARGET_PAGE_SIZE) {
                prot1 |= page_get_flags(addr);
            }
            end = host_end;
        }
        ret = mprotect(g2h(host_start), qemu_host_page_size, prot1 & PAGE_BITS);
        if (ret != 0)
            goto error;
        host_start += qemu_host_page_size;
    }
    if (end < host_end) {
        prot1 = prot;
        for(addr = end; addr < host_end; addr += TARGET_PAGE_SIZE) {
            prot1 |= page_get_flags(addr);
        }
        ret = mprotect(g2h(host_end - qemu_host_page_size), qemu_host_page_size,
                       prot1 & PAGE_BITS);
        if (ret != 0)
            goto error;
        host_end -= qemu_host_page_size;
    }

    /* handle the pages in the middle */
    if (host_start < host_end) {
        ret = mprotect(g2h(host_start), host_end - host_start, prot);
        if (ret != 0)
            goto error;
    }
    page_set_flags(start, start + len, prot | PAGE_VALID);
    mmap_unlock();
    return 0;
error:
    mmap_unlock();
    return ret;
}
Пример #11
0
void target_set_brk(abi_ulong new_brk)
{
    target_original_brk = target_brk = HOST_PAGE_ALIGN(new_brk);
}
Пример #12
0
int load_elf_binary(struct linux_binprm * bprm, struct target_pt_regs * regs,
                    struct image_info * info)
{
    struct elfhdr elf_ex;
    struct elfhdr interp_elf_ex;
    struct exec interp_ex;
    int interpreter_fd = -1; /* avoid warning */
    abi_ulong load_addr, load_bias;
    int load_addr_set = 0;
    unsigned int interpreter_type = INTERPRETER_NONE;
    unsigned char ibcs2_interpreter;
    int i;
    abi_ulong mapped_addr;
    struct elf_phdr * elf_ppnt;
    struct elf_phdr *elf_phdata;
    abi_ulong elf_bss, k, elf_brk;
    int retval;
    char * elf_interpreter;
    abi_ulong elf_entry, interp_load_addr = 0;
    int status;
    abi_ulong start_code, end_code, start_data, end_data;
    abi_ulong reloc_func_desc = 0;
    abi_ulong elf_stack;
    char passed_fileno[6];

    ibcs2_interpreter = 0;
    status = 0;
    load_addr = 0;
    load_bias = 0;
    elf_ex = *((struct elfhdr *) bprm->buf);          /* exec-header */
#ifdef BSWAP_NEEDED
    bswap_ehdr(&elf_ex);
#endif

    /* First of all, some simple consistency checks */
    if ((elf_ex.e_type != ET_EXEC && elf_ex.e_type != ET_DYN) ||
                                (! elf_check_arch(elf_ex.e_machine))) {
            return -ENOEXEC;
    }

    bprm->p = copy_elf_strings(1, &bprm->filename, bprm->page, bprm->p);
    bprm->p = copy_elf_strings(bprm->envc,bprm->envp,bprm->page,bprm->p);
    bprm->p = copy_elf_strings(bprm->argc,bprm->argv,bprm->page,bprm->p);
    if (!bprm->p) {
        retval = -E2BIG;
    }

    /* Now read in all of the header information */
    elf_phdata = (struct elf_phdr *)malloc(elf_ex.e_phentsize*elf_ex.e_phnum);
    if (elf_phdata == NULL) {
        return -ENOMEM;
    }

    retval = lseek(bprm->fd, elf_ex.e_phoff, SEEK_SET);
    if(retval > 0) {
        retval = read(bprm->fd, (char *) elf_phdata,
                                elf_ex.e_phentsize * elf_ex.e_phnum);
    }

    if (retval < 0) {
        perror("load_elf_binary");
        exit(-1);
        free (elf_phdata);
        return -errno;
    }

#ifdef BSWAP_NEEDED
    elf_ppnt = elf_phdata;
    for (i=0; i<elf_ex.e_phnum; i++, elf_ppnt++) {
        bswap_phdr(elf_ppnt);
    }
#endif
    elf_ppnt = elf_phdata;

    elf_bss = 0;
    elf_brk = 0;


    elf_stack = ~((abi_ulong)0UL);
    elf_interpreter = NULL;
    start_code = ~((abi_ulong)0UL);
    end_code = 0;
    start_data = 0;
    end_data = 0;
    interp_ex.a_info = 0;

    for(i=0;i < elf_ex.e_phnum; i++) {
        if (elf_ppnt->p_type == PT_INTERP) {
            if ( elf_interpreter != NULL )
            {
                free (elf_phdata);
                free(elf_interpreter);
                close(bprm->fd);
                return -EINVAL;
            }

            /* This is the program interpreter used for
             * shared libraries - for now assume that this
             * is an a.out format binary
             */

            elf_interpreter = (char *)malloc(elf_ppnt->p_filesz);

            if (elf_interpreter == NULL) {
                free (elf_phdata);
                close(bprm->fd);
                return -ENOMEM;
            }

            retval = lseek(bprm->fd, elf_ppnt->p_offset, SEEK_SET);
            if(retval >= 0) {
                retval = read(bprm->fd, elf_interpreter, elf_ppnt->p_filesz);
            }
            if(retval < 0) {
                perror("load_elf_binary2");
                exit(-1);
            }

            /* If the program interpreter is one of these two,
               then assume an iBCS2 image. Otherwise assume
               a native linux image. */

            /* JRP - Need to add X86 lib dir stuff here... */

            if (strcmp(elf_interpreter,"/usr/lib/libc.so.1") == 0 ||
                strcmp(elf_interpreter,"/usr/lib/ld.so.1") == 0) {
              ibcs2_interpreter = 1;
            }

#if 0
            printf("Using ELF interpreter %s\n", path(elf_interpreter));
#endif
            if (retval >= 0) {
                retval = open(path(elf_interpreter), O_RDONLY);
                if(retval >= 0) {
                    interpreter_fd = retval;
                }
                else {
                    perror(elf_interpreter);
                    exit(-1);
                    /* retval = -errno; */
                }
            }

            if (retval >= 0) {
                retval = lseek(interpreter_fd, 0, SEEK_SET);
                if(retval >= 0) {
                    retval = read(interpreter_fd,bprm->buf,128);
                }
            }
            if (retval >= 0) {
                interp_ex = *((struct exec *) bprm->buf); /* aout exec-header */
                interp_elf_ex = *((struct elfhdr *) bprm->buf); /* elf exec-header */
            }
            if (retval < 0) {
                perror("load_elf_binary3");
                exit(-1);
                free (elf_phdata);
                free(elf_interpreter);
                close(bprm->fd);
                return retval;
            }
        }
        elf_ppnt++;
    }

    /* Some simple consistency checks for the interpreter */
    if (elf_interpreter){
        interpreter_type = INTERPRETER_ELF | INTERPRETER_AOUT;

        /* Now figure out which format our binary is */
        if ((N_MAGIC(interp_ex) != OMAGIC) && (N_MAGIC(interp_ex) != ZMAGIC) &&
                (N_MAGIC(interp_ex) != QMAGIC)) {
          interpreter_type = INTERPRETER_ELF;
        }

        if (interp_elf_ex.e_ident[0] != 0x7f ||
                strncmp((char *)&interp_elf_ex.e_ident[1], "ELF",3) != 0) {
            interpreter_type &= ~INTERPRETER_ELF;
        }

        if (!interpreter_type) {
            free(elf_interpreter);
            free(elf_phdata);
            close(bprm->fd);
            return -ELIBBAD;
        }
    }

    /* OK, we are done with that, now set up the arg stuff,
       and then start this sucker up */

    {
        char * passed_p;

        if (interpreter_type == INTERPRETER_AOUT) {
            snprintf(passed_fileno, sizeof(passed_fileno), "%d", bprm->fd);
            passed_p = passed_fileno;

            if (elf_interpreter) {
                bprm->p = copy_elf_strings(1,&passed_p,bprm->page,bprm->p);
                bprm->argc++;
            }
        }
        if (!bprm->p) {
            if (elf_interpreter) {
                free(elf_interpreter);
            }
            free (elf_phdata);
            close(bprm->fd);
            return -E2BIG;
        }
    }

    /* OK, This is the point of no return */
    info->end_data = 0;
    info->end_code = 0;
    info->start_mmap = (abi_ulong)ELF_START_MMAP;
    info->mmap = 0;
    elf_entry = (abi_ulong) elf_ex.e_entry;

#if defined(CONFIG_USE_GUEST_BASE)
    /*
     * In case where user has not explicitly set the guest_base, we
     * probe here that should we set it automatically.
     */
    if (!have_guest_base) {
        /*
         * Go through ELF program header table and find out whether
	 * any of the segments drop below our current mmap_min_addr and
         * in that case set guest_base to corresponding address.
         */
        for (i = 0, elf_ppnt = elf_phdata; i < elf_ex.e_phnum;
            i++, elf_ppnt++) {
            if (elf_ppnt->p_type != PT_LOAD)
                continue;
            if (HOST_PAGE_ALIGN(elf_ppnt->p_vaddr) < mmap_min_addr) {
                guest_base = HOST_PAGE_ALIGN(mmap_min_addr);
                break;
            }
        }
    }
#endif /* CONFIG_USE_GUEST_BASE */

    /* Do this so that we can load the interpreter, if need be.  We will
       change some of these later */
    info->rss = 0;
    bprm->p = setup_arg_pages(bprm->p, bprm, info);
    info->start_stack = bprm->p;

    /* Now we do a little grungy work by mmaping the ELF image into
     * the correct location in memory.  At this point, we assume that
     * the image should be loaded at fixed address, not at a variable
     * address.
     */

    for(i = 0, elf_ppnt = elf_phdata; i < elf_ex.e_phnum; i++, elf_ppnt++) {
        int elf_prot = 0;
        int elf_flags = 0;
        abi_ulong error;

        if (elf_ppnt->p_type != PT_LOAD)
            continue;

        if (elf_ppnt->p_flags & PF_R) elf_prot |= PROT_READ;
        if (elf_ppnt->p_flags & PF_W) elf_prot |= PROT_WRITE;
        if (elf_ppnt->p_flags & PF_X) elf_prot |= PROT_EXEC;
        elf_flags = MAP_PRIVATE | MAP_DENYWRITE;
        if (elf_ex.e_type == ET_EXEC || load_addr_set) {
            elf_flags |= MAP_FIXED;
        } else if (elf_ex.e_type == ET_DYN) {
            /* Try and get dynamic programs out of the way of the default mmap
               base, as well as whatever program they might try to exec.  This
               is because the brk will follow the loader, and is not movable.  */
            /* NOTE: for qemu, we do a big mmap to get enough space
               without hardcoding any address */
            error = target_mmap(0, ET_DYN_MAP_SIZE,
                                PROT_NONE, MAP_PRIVATE | MAP_ANON,
                                -1, 0);
            if (error == -1) {
                perror("mmap");
                exit(-1);
            }
            load_bias = TARGET_ELF_PAGESTART(error - elf_ppnt->p_vaddr);
        }

        error = target_mmap(TARGET_ELF_PAGESTART(load_bias + elf_ppnt->p_vaddr),
                            (elf_ppnt->p_filesz +
                             TARGET_ELF_PAGEOFFSET(elf_ppnt->p_vaddr)),
                            elf_prot,
                            (MAP_FIXED | MAP_PRIVATE | MAP_DENYWRITE),
                            bprm->fd,
                            (elf_ppnt->p_offset -
                             TARGET_ELF_PAGEOFFSET(elf_ppnt->p_vaddr)));
        if (error == -1) {
            perror("mmap");
            exit(-1);
        }

#ifdef LOW_ELF_STACK
        if (TARGET_ELF_PAGESTART(elf_ppnt->p_vaddr) < elf_stack)
            elf_stack = TARGET_ELF_PAGESTART(elf_ppnt->p_vaddr);
#endif

        if (!load_addr_set) {
            load_addr_set = 1;
            load_addr = elf_ppnt->p_vaddr - elf_ppnt->p_offset;
            if (elf_ex.e_type == ET_DYN) {
                load_bias += error -
                    TARGET_ELF_PAGESTART(load_bias + elf_ppnt->p_vaddr);
                load_addr += load_bias;
                reloc_func_desc = load_bias;
            }
        }
        k = elf_ppnt->p_vaddr;
        if (k < start_code)
            start_code = k;
        if (start_data < k)
            start_data = k;
        k = elf_ppnt->p_vaddr + elf_ppnt->p_filesz;
        if (k > elf_bss)
            elf_bss = k;
        if ((elf_ppnt->p_flags & PF_X) && end_code <  k)
            end_code = k;
        if (end_data < k)
            end_data = k;
        k = elf_ppnt->p_vaddr + elf_ppnt->p_memsz;
        if (k > elf_brk) elf_brk = k;
    }

    elf_entry += load_bias;
    elf_bss += load_bias;
    elf_brk += load_bias;
    start_code += load_bias;
    end_code += load_bias;
    start_data += load_bias;
    end_data += load_bias;

    if (elf_interpreter) {
        if (interpreter_type & 1) {
            elf_entry = load_aout_interp(&interp_ex, interpreter_fd);
        }
        else if (interpreter_type & 2) {
            elf_entry = load_elf_interp(&interp_elf_ex, interpreter_fd,
                                            &interp_load_addr);
        }
        reloc_func_desc = interp_load_addr;

        close(interpreter_fd);
        free(elf_interpreter);

        if (elf_entry == ~((abi_ulong)0UL)) {
            printf("Unable to load interpreter\n");
            free(elf_phdata);
            exit(-1);
            return 0;
        }
    }

    free(elf_phdata);

    if (qemu_log_enabled())
        load_symbols(&elf_ex, bprm->fd);

    if (interpreter_type != INTERPRETER_AOUT) close(bprm->fd);
    info->personality = (ibcs2_interpreter ? PER_SVR4 : PER_LINUX);

#ifdef LOW_ELF_STACK
    info->start_stack = bprm->p = elf_stack - 4;
#endif
    bprm->p = create_elf_tables(bprm->p,
                    bprm->argc,
                    bprm->envc,
                    &elf_ex,
                    load_addr, load_bias,
                    interp_load_addr,
                    (interpreter_type == INTERPRETER_AOUT ? 0 : 1),
                    info);
    info->load_addr = reloc_func_desc;
    info->start_brk = info->brk = elf_brk;
    info->end_code = end_code;
    info->start_code = start_code;
    info->start_data = start_data;
    info->end_data = end_data;
    info->start_stack = bprm->p;

    /* Calling set_brk effectively mmaps the pages that we need for the bss and break
       sections */
    set_brk(elf_bss, elf_brk);

    padzero(elf_bss, elf_brk);

#if 0
    printf("(start_brk) %x\n" , info->start_brk);
    printf("(end_code) %x\n" , info->end_code);
    printf("(start_code) %x\n" , info->start_code);
    printf("(end_data) %x\n" , info->end_data);
    printf("(start_stack) %x\n" , info->start_stack);
    printf("(brk) %x\n" , info->brk);
#endif

    if ( info->personality == PER_SVR4 )
    {
            /* Why this, you ask???  Well SVr4 maps page 0 as read-only,
               and some applications "depend" upon this behavior.
               Since we do not have the power to recompile these, we
               emulate the SVr4 behavior.  Sigh.  */
            mapped_addr = target_mmap(0, qemu_host_page_size, PROT_READ | PROT_EXEC,
                                      MAP_FIXED | MAP_PRIVATE, -1, 0);
    }

    info->entry = elf_entry;

    return 0;
}
Пример #13
0
/* NOTE: all the constants are the HOST ones */
abi_long target_mmap(abi_ulong start, abi_ulong len, int prot,
                     int flags, int fd, abi_ulong offset)
{
    abi_ulong ret, end, real_start, real_end, retaddr, host_offset, host_len;

    mmap_lock();
#ifdef DEBUG_MMAP
    {
        printf("mmap: start=0x" TARGET_ABI_FMT_lx
               " len=0x" TARGET_ABI_FMT_lx " prot=%c%c%c flags=",
               start, len,
               prot & PROT_READ ? 'r' : '-',
               prot & PROT_WRITE ? 'w' : '-',
               prot & PROT_EXEC ? 'x' : '-');
        if (flags & MAP_FIXED)
            printf("MAP_FIXED ");
        if (flags & MAP_ANONYMOUS)
            printf("MAP_ANON ");
        switch(flags & MAP_TYPE) {
        case MAP_PRIVATE:
            printf("MAP_PRIVATE ");
            break;
        case MAP_SHARED:
            printf("MAP_SHARED ");
            break;
        default:
            printf("[MAP_TYPE=0x%x] ", flags & MAP_TYPE);
            break;
        }
        printf("fd=%d offset=" TARGET_ABI_FMT_lx "\n", fd, offset);
    }
#endif

    if (offset & ~TARGET_PAGE_MASK) {
        errno = EINVAL;
        goto fail;
    }

    len = TARGET_PAGE_ALIGN(len);
    if (len == 0)
        goto the_end;
    real_start = start & qemu_host_page_mask;
    host_offset = offset & qemu_host_page_mask;

    /* If the user is asking for the kernel to find a location, do that
       before we truncate the length for mapping files below.  */
    if (!(flags & MAP_FIXED)) {
        host_len = len + offset - host_offset;
        host_len = HOST_PAGE_ALIGN(host_len);
        start = mmap_find_vma(real_start, host_len);
        if (start == (abi_ulong)-1) {
            errno = ENOMEM;
            goto fail;
        }
    }

    /* When mapping files into a memory area larger than the file, accesses
       to pages beyond the file size will cause a SIGBUS. 

       For example, if mmaping a file of 100 bytes on a host with 4K pages
       emulating a target with 8K pages, the target expects to be able to
       access the first 8K. But the host will trap us on any access beyond
       4K.  

       When emulating a target with a larger page-size than the hosts, we
       may need to truncate file maps at EOF and add extra anonymous pages
       up to the targets page boundary.  */

    if ((qemu_real_host_page_size < TARGET_PAGE_SIZE)
        && !(flags & MAP_ANONYMOUS)) {
       struct stat sb;

       if (fstat (fd, &sb) == -1)
           goto fail;

       /* Are we trying to create a map beyond EOF?.  */
       if (offset + len > sb.st_size) {
           /* If so, truncate the file map at eof aligned with 
              the hosts real pagesize. Additional anonymous maps
              will be created beyond EOF.  */
           len = (sb.st_size - offset);
           len += qemu_real_host_page_size - 1;
           len &= ~(qemu_real_host_page_size - 1);
       }
    }

    if (!(flags & MAP_FIXED)) {
        unsigned long host_start;
        void *p;

        host_len = len + offset - host_offset;
        host_len = HOST_PAGE_ALIGN(host_len);

        /* Note: we prefer to control the mapping address. It is
           especially important if qemu_host_page_size >
           qemu_real_host_page_size */
        p = mmap(g2h(start), host_len, prot,
                 flags | MAP_FIXED | MAP_ANONYMOUS, -1, 0);
        if (p == MAP_FAILED)
            goto fail;
        /* update start so that it points to the file position at 'offset' */
        host_start = (unsigned long)p;
        if (!(flags & MAP_ANONYMOUS)) {
            p = mmap(g2h(start), len, prot,
                     flags | MAP_FIXED, fd, host_offset);
            if (p == MAP_FAILED) {
                munmap(g2h(start), host_len);
                goto fail;
            }
            host_start += offset - host_offset;
        }
        start = h2g(host_start);
    } else {
        if (start & ~TARGET_PAGE_MASK) {
            errno = EINVAL;
            goto fail;
        }
        end = start + len;
        real_end = HOST_PAGE_ALIGN(end);

	/*
	 * Test if requested memory area fits target address space
	 * It can fail only on 64-bit host with 32-bit target.
	 * On any other target/host host mmap() handles this error correctly.
	 */
        if ((unsigned long)start + len - 1 > (abi_ulong) -1) {
            errno = EINVAL;
            goto fail;
        }

        /* worst case: we cannot map the file because the offset is not
           aligned, so we read it */
        if (!(flags & MAP_ANONYMOUS) &&
            (offset & ~qemu_host_page_mask) != (start & ~qemu_host_page_mask)) {
            /* msync() won't work here, so we return an error if write is
               possible while it is a shared mapping */
            if ((flags & MAP_TYPE) == MAP_SHARED &&
                (prot & PROT_WRITE)) {
                errno = EINVAL;
                goto fail;
            }
            retaddr = target_mmap(start, len, prot | PROT_WRITE,
                                  MAP_FIXED | MAP_PRIVATE | MAP_ANONYMOUS,
                                  -1, 0);
            if (retaddr == -1)
                goto fail;
            if (pread(fd, g2h(start), len, offset) == -1)
                goto fail;
            if (!(prot & PROT_WRITE)) {
                ret = target_mprotect(start, len, prot);
                if (ret != 0) {
                    start = ret;
                    goto the_end;
                }
            }
            goto the_end;
        }
        
        /* handle the start of the mapping */
        if (start > real_start) {
            if (real_end == real_start + qemu_host_page_size) {
                /* one single host page */
                ret = mmap_frag(real_start, start, end,
                                prot, flags, fd, offset);
                if (ret == -1)
                    goto fail;
                goto the_end1;
            }
            ret = mmap_frag(real_start, start, real_start + qemu_host_page_size,
                            prot, flags, fd, offset);
            if (ret == -1)
                goto fail;
            real_start += qemu_host_page_size;
        }
        /* handle the end of the mapping */
        if (end < real_end) {
            ret = mmap_frag(real_end - qemu_host_page_size,
                            real_end - qemu_host_page_size, real_end,
                            prot, flags, fd,
                            offset + real_end - qemu_host_page_size - start);
            if (ret == -1)
                goto fail;
            real_end -= qemu_host_page_size;
        }

        /* map the middle (easier) */
        if (real_start < real_end) {
            void *p;
            unsigned long offset1;
            if (flags & MAP_ANONYMOUS)
                offset1 = 0;
            else
                offset1 = offset + real_start - start;
            p = mmap(g2h(real_start), real_end - real_start,
                     prot, flags, fd, offset1);
            if (p == MAP_FAILED)
                goto fail;
        }
    }
 the_end1:
    page_set_flags(start, start + len, prot | PAGE_VALID);
 the_end:
#ifdef DEBUG_MMAP
    printf("ret=0x" TARGET_ABI_FMT_lx "\n", start);
    page_dump(stdout);
    printf("\n");
#endif
    tb_invalidate_phys_range(start, start + len);
    mmap_unlock();
    return start;
fail:
    mmap_unlock();
    return -1;
}
Пример #14
0
/*
 * Find and reserve a free memory area of size 'size'. The search
 * starts at 'start'.
 * It must be called with mmap_lock() held.
 * Return -1 if error.
 */
abi_ulong mmap_find_vma(abi_ulong start, abi_ulong size)
{
    void *ptr, *prev;
    abi_ulong addr;
    int wrapped, repeat;

    /* If 'start' == 0, then a default start address is used. */
    if (start == 0) {
        start = mmap_next_start;
    } else {
        start &= qemu_host_page_mask;
    }

    size = HOST_PAGE_ALIGN(size);

#ifdef CONFIG_USE_GUEST_BASE
    if (RESERVED_VA) {
        return mmap_find_vma_reserved(start, size);
    }
#endif

    addr = start;
    wrapped = repeat = 0;
    prev = 0;

    for (;; prev = ptr) {
        /*
         * Reserve needed memory area to avoid a race.
         * It should be discarded using:
         *  - mmap() with MAP_FIXED flag
         *  - mremap() with MREMAP_FIXED flag
         *  - shmat() with SHM_REMAP flag
         */
        ptr = mmap(g2h(addr), size, PROT_NONE,
                   MAP_ANONYMOUS|MAP_PRIVATE|MAP_NORESERVE, -1, 0);

        /* ENOMEM, if host address space has no memory */
        if (ptr == MAP_FAILED) {
            return (abi_ulong)-1;
        }

        /* Count the number of sequential returns of the same address.
           This is used to modify the search algorithm below.  */
        repeat = (ptr == prev ? repeat + 1 : 0);

        if (h2g_valid(ptr + size - 1)) {
            addr = h2g(ptr);

            if ((addr & ~TARGET_PAGE_MASK) == 0) {
                /* Success.  */
                if (start == mmap_next_start && addr >= TASK_UNMAPPED_BASE) {
                    mmap_next_start = addr + size;
                }
                return addr;
            }

            /* The address is not properly aligned for the target.  */
            switch (repeat) {
            case 0:
                /* Assume the result that the kernel gave us is the
                   first with enough free space, so start again at the
                   next higher target page.  */
                addr = TARGET_PAGE_ALIGN(addr);
                break;
            case 1:
                /* Sometimes the kernel decides to perform the allocation
                   at the top end of memory instead.  */
                addr &= TARGET_PAGE_MASK;
                break;
            case 2:
                /* Start over at low memory.  */
                addr = 0;
                break;
            default:
                /* Fail.  This unaligned block must the last.  */
                addr = -1;
                break;
            }
        } else {
            /* Since the result the kernel gave didn't fit, start
               again at low memory.  If any repetition, fail.  */
            addr = (repeat ? -1 : 0);
        }

        /* Unmap and try again.  */
        munmap(ptr, size);

        /* ENOMEM if we checked the whole of the target address space.  */
        if (addr == (abi_ulong)-1) {
            return (abi_ulong)-1;
        } else if (addr == 0) {
            if (wrapped) {
                return (abi_ulong)-1;
            }
            wrapped = 1;
            /* Don't actually use 0 when wrapping, instead indicate
               that we'd truly like an allocation in low memory.  */
            addr = (mmap_min_addr > TARGET_PAGE_SIZE
                     ? TARGET_PAGE_ALIGN(mmap_min_addr)
                     : TARGET_PAGE_SIZE);
        } else if (wrapped && addr >= start) {
            return (abi_ulong)-1;
        }
    }
}