| // SPDX-License-Identifier: GPL-2.0 |
| /****************************************************************************/ |
| /* |
| * 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) |
| */ |
| |
| #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt |
| |
| #include <linux/kernel.h> |
| #include <linux/sched.h> |
| #include <linux/sched/task_stack.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/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/uaccess.h> |
| #include <linux/vmalloc.h> |
| |
| #include <asm/byteorder.h> |
| #include <asm/unaligned.h> |
| #include <asm/cacheflush.h> |
| #include <asm/page.h> |
| |
| /****************************************************************************/ |
| |
| /* |
| * 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 */ |
| bool 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) |
| { |
| pr_warn("Process %s:%d received signr %d and should have core dumped\n", |
| current->comm, current->pid, cprm->siginfo->si_signo); |
| return 1; |
| } |
| |
| /****************************************************************************/ |
| /* |
| * create_flat_tables() parses the env- and arg-strings in new user |
| * memory and creates the pointer tables from them, and puts their |
| * addresses on the "stack", recording the new stack pointer value. |
| */ |
| |
| static int create_flat_tables(struct linux_binprm *bprm, unsigned long arg_start) |
| { |
| char __user *p; |
| unsigned long __user *sp; |
| long i, len; |
| |
| p = (char __user *)arg_start; |
| sp = (unsigned long __user *)current->mm->start_stack; |
| |
| sp -= bprm->envc + 1; |
| sp -= bprm->argc + 1; |
| sp -= flat_argvp_envp_on_stack() ? 2 : 0; |
| sp -= 1; /* &argc */ |
| |
| current->mm->start_stack = (unsigned long)sp & -FLAT_STACK_ALIGN; |
| sp = (unsigned long __user *)current->mm->start_stack; |
| |
| __put_user(bprm->argc, sp++); |
| if (flat_argvp_envp_on_stack()) { |
| unsigned long argv, envp; |
| argv = (unsigned long)(sp + 2); |
| envp = (unsigned long)(sp + 2 + bprm->argc + 1); |
| __put_user(argv, sp++); |
| __put_user(envp, sp++); |
| } |
| |
| current->mm->arg_start = (unsigned long)p; |
| for (i = bprm->argc; i > 0; i--) { |
| __put_user((unsigned long)p, sp++); |
| len = strnlen_user(p, MAX_ARG_STRLEN); |
| if (!len || len > MAX_ARG_STRLEN) |
| return -EINVAL; |
| p += len; |
| } |
| __put_user(0, sp++); |
| current->mm->arg_end = (unsigned long)p; |
| |
| current->mm->env_start = (unsigned long) p; |
| for (i = bprm->envc; i > 0; i--) { |
| __put_user((unsigned long)p, sp++); |
| len = strnlen_user(p, MAX_ARG_STRLEN); |
| if (!len || len > MAX_ARG_STRLEN) |
| return -EINVAL; |
| p += len; |
| } |
| __put_user(0, sp++); |
| current->mm->env_end = (unsigned long)p; |
| |
| return 0; |
| } |
| |
| /****************************************************************************/ |
| |
| #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, loff_t fpos, char *dst, |
| long len, int fd) |
| { |
| unsigned char *buf; |
| z_stream strm; |
| int ret, retval; |
| |
| pr_debug("decompress_exec(offset=%llx,buf=%p,len=%lx)\n", fpos, dst, len); |
| |
| memset(&strm, 0, sizeof(strm)); |
| strm.workspace = kmalloc(zlib_inflate_workspacesize(), GFP_KERNEL); |
| if (!strm.workspace) |
| return -ENOMEM; |
| |
| buf = kmalloc(LBUFSIZE, GFP_KERNEL); |
| if (!buf) { |
| retval = -ENOMEM; |
| goto out_free; |
| } |
| |
| /* Read in first chunk of data and parse gzip header. */ |
| ret = kernel_read(bprm->file, buf, LBUFSIZE, &fpos); |
| |
| strm.next_in = buf; |
| strm.avail_in = ret; |
| strm.total_in = 0; |
| |
| retval = -ENOEXEC; |
| |
| /* Check minimum size -- gzip header */ |
| if (ret < 10) { |
| pr_debug("file too small?\n"); |
| goto out_free_buf; |
| } |
| |
| /* Check gzip magic number */ |
| if ((buf[0] != 037) || ((buf[1] != 0213) && (buf[1] != 0236))) { |
| pr_debug("unknown compression magic?\n"); |
| goto out_free_buf; |
| } |
| |
| /* Check gzip method */ |
| if (buf[2] != 8) { |
| pr_debug("unknown compression method?\n"); |
| goto out_free_buf; |
| } |
| /* Check gzip flags */ |
| if ((buf[3] & ENCRYPTED) || (buf[3] & CONTINUATION) || |
| (buf[3] & RESERVED)) { |
| pr_debug("unknown flags?\n"); |
| goto out_free_buf; |
| } |
| |
| ret = 10; |
| if (buf[3] & EXTRA_FIELD) { |
| ret += 2 + buf[10] + (buf[11] << 8); |
| if (unlikely(ret >= LBUFSIZE)) { |
| pr_debug("buffer overflow (EXTRA)?\n"); |
| goto out_free_buf; |
| } |
| } |
| if (buf[3] & ORIG_NAME) { |
| while (ret < LBUFSIZE && buf[ret++] != 0) |
| ; |
| if (unlikely(ret == LBUFSIZE)) { |
| pr_debug("buffer overflow (ORIG_NAME)?\n"); |
| goto out_free_buf; |
| } |
| } |
| if (buf[3] & COMMENT) { |
| while (ret < LBUFSIZE && buf[ret++] != 0) |
| ; |
| if (unlikely(ret == LBUFSIZE)) { |
| pr_debug("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) { |
| pr_debug("zlib init failed?\n"); |
| goto out_free_buf; |
| } |
| |
| while ((ret = zlib_inflate(&strm, Z_NO_FLUSH)) == Z_OK) { |
| ret = kernel_read(bprm->file, buf, LBUFSIZE, &fpos); |
| if (ret <= 0) |
| break; |
| len -= ret; |
| |
| strm.next_in = buf; |
| strm.avail_in = ret; |
| strm.total_in = 0; |
| } |
| |
| if (ret < 0) { |
| pr_debug("decompression failed (%d), %s\n", |
| ret, strm.msg); |
| goto out_zlib; |
| } |
| |
| retval = 0; |
| out_zlib: |
| zlib_inflateEnd(&strm); |
| out_free_buf: |
| kfree(buf); |
| out_free: |
| kfree(strm.workspace); |
| return retval; |
| } |
| |
| #endif /* CONFIG_BINFMT_ZFLAT */ |
| |
| /****************************************************************************/ |
| |
| static unsigned long |
| calc_reloc(unsigned long r, struct lib_info *p, int curid, int internalp) |
| { |
| unsigned long addr; |
| int id; |
| unsigned long start_brk; |
| unsigned long start_data; |
| unsigned long text_len; |
| unsigned long start_code; |
| |
| #ifdef CONFIG_BINFMT_SHARED_FLAT |
| if (r == 0) |
| id = curid; /* Relocs of 0 are always self referring */ |
| else { |
| id = (r >> 24) & 0xff; /* Find ID for this reloc */ |
| r &= 0x00ffffff; /* Trim ID off here */ |
| } |
| if (id >= MAX_SHARED_LIBS) { |
| pr_err("reference 0x%lx to shared library %d", r, id); |
| goto failed; |
| } |
| if (curid != id) { |
| if (internalp) { |
| pr_err("reloc address 0x%lx not in same module " |
| "(%d != %d)", r, curid, id); |
| goto failed; |
| } else if (!p->lib_list[id].loaded && |
| load_flat_shared_library(id, p) < 0) { |
| pr_err("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) { |
| pr_err("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)) { |
| pr_err("reloc outside program 0x%lx (0 - 0x%lx/0x%lx)", |
| r, start_brk-start_data+text_len, 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: |
| pr_cont(", killing %s!\n", current->comm); |
| send_sig(SIGSEGV, current, 0); |
| |
| return RELOC_FAILED; |
| } |
| |
| /****************************************************************************/ |
| |
| static void old_reloc(unsigned long rl) |
| { |
| static const char *segment[] = { "TEXT", "DATA", "BSS", "*UNKNOWN*" }; |
| flat_v2_reloc_t r; |
| unsigned long __user *ptr; |
| unsigned long val; |
| |
| r.value = rl; |
| #if defined(CONFIG_COLDFIRE) |
| ptr = (unsigned long __user *)(current->mm->start_code + r.reloc.offset); |
| #else |
| ptr = (unsigned long __user *)(current->mm->start_data + r.reloc.offset); |
| #endif |
| get_user(val, ptr); |
| |
| pr_debug("Relocation of variable at DATASEG+%x " |
| "(address %p, currently %lx) into segment %s\n", |
| r.reloc.offset, ptr, val, segment[r.reloc.type]); |
| |
| switch (r.reloc.type) { |
| case OLD_FLAT_RELOC_TYPE_TEXT: |
| val += current->mm->start_code; |
| break; |
| case OLD_FLAT_RELOC_TYPE_DATA: |
| val += current->mm->start_data; |
| break; |
| case OLD_FLAT_RELOC_TYPE_BSS: |
| val += current->mm->end_data; |
| break; |
| default: |
| pr_err("Unknown relocation type=%x\n", r.reloc.type); |
| break; |
| } |
| put_user(val, ptr); |
| |
| pr_debug("Relocation became %lx\n", val); |
| } |
| |
| /****************************************************************************/ |
| |
| static inline u32 __user *skip_got_header(u32 __user *rp) |
| { |
| if (IS_ENABLED(CONFIG_RISCV)) { |
| /* |
| * RISC-V has a 16 byte GOT PLT header for elf64-riscv |
| * and 8 byte GOT PLT header for elf32-riscv. |
| * Skip the whole GOT PLT header, since it is reserved |
| * for the dynamic linker (ld.so). |
| */ |
| u32 rp_val0, rp_val1; |
| |
| if (get_user(rp_val0, rp)) |
| return rp; |
| if (get_user(rp_val1, rp + 1)) |
| return rp; |
| |
| if (rp_val0 == 0xffffffff && rp_val1 == 0xffffffff) |
| rp += 4; |
| else if (rp_val0 == 0xffffffff) |
| rp += 2; |
| } |
| return rp; |
| } |
| |
| 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, datapos, realdatastart; |
| u32 text_len, data_len, bss_len, stack_len, full_data, flags; |
| unsigned long len, memp, memp_size, extra, rlim; |
| u32 __user *reloc, *rp; |
| struct inode *inode; |
| int i, rev, relocs; |
| loff_t fpos; |
| unsigned long start_code, end_code; |
| ssize_t result; |
| 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) |
| pr_info("Loading file: %s\n", bprm->filename); |
| |
| if (rev != FLAT_VERSION && rev != OLD_FLAT_VERSION) { |
| pr_err("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) { |
| pr_err("shared libraries are not available before rev 0x%lx\n", |
| FLAT_VERSION); |
| ret = -ENOEXEC; |
| goto err; |
| } |
| |
| /* |
| * Make sure the header params are sane. |
| * 28 bits (256 MB) is way more than reasonable in this case. |
| * If some top bits are set we have probable binary corruption. |
| */ |
| if ((text_len | data_len | bss_len | stack_len | full_data) >> 28) { |
| pr_err("bad header\n"); |
| 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)) { |
| pr_err("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) { |
| ret = flush_old_exec(bprm); |
| if (ret) |
| 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 (!IS_ENABLED(CONFIG_MMU) && !(flags & (FLAT_FLAG_RAM|FLAT_FLAG_GZIP))) { |
| /* |
| * this should give us a ROM ptr, but if it doesn't we don't |
| * really care |
| */ |
| pr_debug("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)) { |
| ret = textpos; |
| if (!textpos) |
| ret = -ENOMEM; |
| pr_err("Unable to mmap process text, errno %d\n", ret); |
| goto err; |
| } |
| |
| len = data_len + extra + MAX_SHARED_LIBS * sizeof(unsigned long); |
| len = PAGE_ALIGN(len); |
| realdatastart = vm_mmap(NULL, 0, len, |
| PROT_READ|PROT_WRITE|PROT_EXEC, MAP_PRIVATE, 0); |
| |
| if (realdatastart == 0 || IS_ERR_VALUE(realdatastart)) { |
| ret = realdatastart; |
| if (!realdatastart) |
| ret = -ENOMEM; |
| pr_err("Unable to allocate RAM for process data, " |
| "errno %d\n", ret); |
| vm_munmap(textpos, text_len); |
| goto err; |
| } |
| datapos = ALIGN(realdatastart + |
| MAX_SHARED_LIBS * sizeof(unsigned long), |
| FLAT_DATA_ALIGN); |
| |
| pr_debug("Allocated data+bss+stack (%u bytes): %lx\n", |
| data_len + bss_len + stack_len, datapos); |
| |
| fpos = ntohl(hdr->data_start); |
| #ifdef CONFIG_BINFMT_ZFLAT |
| if (flags & FLAT_FLAG_GZDATA) { |
| result = decompress_exec(bprm, fpos, (char *)datapos, |
| full_data, 0); |
| } else |
| #endif |
| { |
| result = read_code(bprm->file, datapos, fpos, |
| full_data); |
| } |
| if (IS_ERR_VALUE(result)) { |
| ret = result; |
| pr_err("Unable to read data+bss, errno %d\n", ret); |
| vm_munmap(textpos, text_len); |
| vm_munmap(realdatastart, len); |
| goto err; |
| } |
| |
| reloc = (u32 __user *) |
| (datapos + (ntohl(hdr->reloc_start) - text_len)); |
| memp = realdatastart; |
| memp_size = len; |
| } else { |
| |
| len = text_len + data_len + extra + MAX_SHARED_LIBS * sizeof(u32); |
| len = PAGE_ALIGN(len); |
| textpos = vm_mmap(NULL, 0, len, |
| PROT_READ | PROT_EXEC | PROT_WRITE, MAP_PRIVATE, 0); |
| |
| if (!textpos || IS_ERR_VALUE(textpos)) { |
| ret = textpos; |
| if (!textpos) |
| ret = -ENOMEM; |
| pr_err("Unable to allocate RAM for process text/data, " |
| "errno %d\n", ret); |
| goto err; |
| } |
| |
| realdatastart = textpos + ntohl(hdr->data_start); |
| datapos = ALIGN(realdatastart + |
| MAX_SHARED_LIBS * sizeof(u32), |
| FLAT_DATA_ALIGN); |
| |
| reloc = (u32 __user *) |
| (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) { |
| #ifndef CONFIG_MMU |
| 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 |
| /* |
| * This is used on MMU systems mainly for testing. |
| * Let's use a kernel buffer to simplify things. |
| */ |
| long unz_text_len = text_len - sizeof(struct flat_hdr); |
| long unz_len = unz_text_len + full_data; |
| char *unz_data = vmalloc(unz_len); |
| if (!unz_data) { |
| result = -ENOMEM; |
| } else { |
| result = decompress_exec(bprm, sizeof(struct flat_hdr), |
| unz_data, unz_len, 0); |
| if (result == 0 && |
| (copy_to_user((void __user *)textpos + sizeof(struct flat_hdr), |
| unz_data, unz_text_len) || |
| copy_to_user((void __user *)datapos, |
| unz_data + unz_text_len, full_data))) |
| result = -EFAULT; |
| vfree(unz_data); |
| } |
| #endif |
| } else if (flags & FLAT_FLAG_GZDATA) { |
| result = read_code(bprm->file, textpos, 0, text_len); |
| if (!IS_ERR_VALUE(result)) { |
| #ifndef CONFIG_MMU |
| result = decompress_exec(bprm, text_len, (char *) datapos, |
| full_data, 0); |
| #else |
| char *unz_data = vmalloc(full_data); |
| if (!unz_data) { |
| result = -ENOMEM; |
| } else { |
| result = decompress_exec(bprm, text_len, |
| unz_data, full_data, 0); |
| if (result == 0 && |
| copy_to_user((void __user *)datapos, |
| unz_data, full_data)) |
| result = -EFAULT; |
| vfree(unz_data); |
| } |
| #endif |
| } |
| } else |
| #endif /* CONFIG_BINFMT_ZFLAT */ |
| { |
| result = read_code(bprm->file, textpos, 0, text_len); |
| if (!IS_ERR_VALUE(result)) |
| result = read_code(bprm->file, datapos, |
| ntohl(hdr->data_start), |
| full_data); |
| } |
| if (IS_ERR_VALUE(result)) { |
| ret = result; |
| pr_err("Unable to read code+data+bss, errno %d\n", ret); |
| vm_munmap(textpos, text_len + data_len + extra + |
| MAX_SHARED_LIBS * sizeof(u32)); |
| goto err; |
| } |
| } |
| |
| start_code = textpos + sizeof(struct flat_hdr); |
| end_code = textpos + text_len; |
| text_len -= sizeof(struct flat_hdr); /* the real code len */ |
| |
| /* The main program needs a little extra setup in the task structure */ |
| if (id == 0) { |
| current->mm->start_code = start_code; |
| current->mm->end_code = end_code; |
| current->mm->start_data = datapos; |
| current->mm->end_data = datapos + data_len; |
| /* |
| * set up the brk stuff, uses any slack left in data/bss/stack |
| * allocation. We put the brk after the bss (between the bss |
| * and stack) like other platforms. |
| * Userspace code relies on the stack pointer starting out at |
| * an address right at the end of a page. |
| */ |
| current->mm->start_brk = datapos + data_len + bss_len; |
| current->mm->brk = (current->mm->start_brk + 3) & ~3; |
| #ifndef CONFIG_MMU |
| current->mm->context.end_brk = memp + memp_size - stack_len; |
| #endif |
| } |
| |
| if (flags & FLAT_FLAG_KTRACE) { |
| pr_info("Mapping is %lx, Entry point is %x, data_start is %x\n", |
| textpos, 0x00ffffff&ntohl(hdr->entry), ntohl(hdr->data_start)); |
| pr_info("%s %s: TEXT=%lx-%lx DATA=%lx-%lx BSS=%lx-%lx\n", |
| id ? "Lib" : "Load", bprm->filename, |
| start_code, end_code, datapos, datapos + data_len, |
| datapos + data_len, (datapos + data_len + bss_len + 3) & ~3); |
| } |
| |
| /* Store the current module values into the global library structure */ |
| libinfo->lib_list[id].start_code = start_code; |
| libinfo->lib_list[id].start_data = datapos; |
| libinfo->lib_list[id].start_brk = datapos + data_len + bss_len; |
| libinfo->lib_list[id].text_len = text_len; |
| libinfo->lib_list[id].loaded = 1; |
| libinfo->lib_list[id].entry = (0x00ffffff & ntohl(hdr->entry)) + textpos; |
| libinfo->lib_list[id].build_date = ntohl(hdr->build_date); |
| |
| /* |
| * We just load the allocations into some temporary memory to |
| * help simplify all this mumbo jumbo |
| * |
| * We've got two different sections of relocation entries. |
| * The first is the GOT which resides at the beginning of the data segment |
| * and is terminated with a -1. This one can be relocated in place. |
| * The second is the extra relocation entries tacked after the image's |
| * data segment. These require a little more processing as the entry is |
| * really an offset into the image which contains an offset into the |
| * image. |
| */ |
| if (flags & FLAT_FLAG_GOTPIC) { |
| rp = skip_got_header((u32 __user *) datapos); |
| for (; ; rp++) { |
| u32 addr, rp_val; |
| if (get_user(rp_val, rp)) |
| return -EFAULT; |
| if (rp_val == 0xffffffff) |
| break; |
| if (rp_val) { |
| addr = calc_reloc(rp_val, libinfo, id, 0); |
| if (addr == RELOC_FAILED) { |
| ret = -ENOEXEC; |
| goto err; |
| } |
| if (put_user(addr, rp)) |
| return -EFAULT; |
| } |
| } |
| } |
| |
| /* |
| * Now run through the relocation entries. |
| * We've got to be careful here as C++ produces relocatable zero |
| * entries in the constructor and destructor tables which are then |
| * tested for being not zero (which will always occur unless we're |
| * based from address zero). This causes an endless loop as __start |
| * is at zero. The solution used is to not relocate zero addresses. |
| * This has the negative side effect of not allowing a global data |
| * reference to be statically initialised to _stext (I've moved |
| * __start to address 4 so that is okay). |
| */ |
| if (rev > OLD_FLAT_VERSION) { |
| u32 __maybe_unused persistent = 0; |
| for (i = 0; i < relocs; i++) { |
| u32 addr, relval; |
| |
| /* |
| * Get the address of the pointer to be |
| * relocated (of course, the address has to be |
| * relocated first). |
| */ |
| if (get_user(relval, reloc + i)) |
| return -EFAULT; |
| relval = ntohl(relval); |
| if (flat_set_persistent(relval, &persistent)) |
| continue; |
| addr = flat_get_relocate_addr(relval); |
| rp = (u32 __user *)calc_reloc(addr, libinfo, id, 1); |
| if (rp == (u32 __user *)RELOC_FAILED) { |
| ret = -ENOEXEC; |
| goto err; |
| } |
| |
| /* Get the pointer's value. */ |
| ret = flat_get_addr_from_rp(rp, relval, flags, |
| &addr, &persistent); |
| if (unlikely(ret)) |
| goto err; |
| |
| if (addr != 0) { |
| /* |
| * Do the relocation. PIC relocs in the data section are |
| * already in target order |
| */ |
| if ((flags & FLAT_FLAG_GOTPIC) == 0) |
| addr = ntohl(addr); |
| addr = calc_reloc(addr, libinfo, id, 0); |
| if (addr == RELOC_FAILED) { |
| ret = -ENOEXEC; |
| goto err; |
| } |
| |
| /* Write back the relocated pointer. */ |
| ret = flat_put_addr_at_rp(rp, addr, relval); |
| if (unlikely(ret)) |
| goto err; |
| } |
| } |
| } else { |
| for (i = 0; i < relocs; i++) { |
| u32 relval; |
| if (get_user(relval, reloc + i)) |
| return -EFAULT; |
| relval = ntohl(relval); |
| old_reloc(relval); |
| } |
| } |
| |
| flush_icache_range(start_code, end_code); |
| |
| /* zero the BSS, BRK and stack areas */ |
| if (clear_user((void __user *)(datapos + data_len), bss_len + |
| (memp + memp_size - stack_len - /* end brk */ |
| libinfo->lib_list[id].start_brk) + /* start brk */ |
| stack_len)) |
| return -EFAULT; |
| |
| return 0; |
| err: |
| return ret; |
| } |
| |
| |
| /****************************************************************************/ |
| #ifdef CONFIG_BINFMT_SHARED_FLAT |
| |
| /* |
| * Load a shared library into memory. The library gets its own data |
| * segment (including bss) but not argv/argc/environ. |
| */ |
| |
| static int load_flat_shared_library(int id, struct lib_info *libs) |
| { |
| /* |
| * This is a fake bprm struct; only the members "buf", "file" and |
| * "filename" are actually used. |
| */ |
| struct linux_binprm bprm; |
| int res; |
| char buf[16]; |
| loff_t pos = 0; |
| |
| memset(&bprm, 0, sizeof(bprm)); |
| |
| /* Create the file name */ |
| sprintf(buf, "/lib/lib%d.so", id); |
| |
| /* Open the file up */ |
| bprm.filename = buf; |
| bprm.file = open_exec(bprm.filename); |
| res = PTR_ERR(bprm.file); |
| if (IS_ERR(bprm.file)) |
| return res; |
| |
| res = kernel_read(bprm.file, bprm.buf, BINPRM_BUF_SIZE, &pos); |
| |
| if (res >= 0) |
| res = load_flat_file(&bprm, libs, id, NULL); |
| |
| allow_write_access(bprm.file); |
| fput(bprm.file); |
| |
| return res; |
| } |
| |
| #endif /* CONFIG_BINFMT_SHARED_FLAT */ |
| /****************************************************************************/ |
| |
| /* |
| * These are the functions used to load flat style executables and shared |
| * libraries. There is no binary dependent code anywhere else. |
| */ |
| |
| static int load_flat_binary(struct linux_binprm *bprm) |
| { |
| struct lib_info libinfo; |
| struct pt_regs *regs = current_pt_regs(); |
| unsigned long stack_len = 0; |
| unsigned long start_addr; |
| int res; |
| int i, j; |
| |
| memset(&libinfo, 0, sizeof(libinfo)); |
| |
| /* |
| * We have to add the size of our arguments to our stack size |
| * otherwise it's too easy for users to create stack overflows |
| * by passing in a huge argument list. And yes, we have to be |
| * pedantic and include space for the argv/envp array as it may have |
| * a lot of entries. |
| */ |
| #ifndef CONFIG_MMU |
| stack_len += PAGE_SIZE * MAX_ARG_PAGES - bprm->p; /* the strings */ |
| #endif |
| stack_len += (bprm->argc + 1) * sizeof(char *); /* the argv array */ |
| stack_len += (bprm->envc + 1) * sizeof(char *); /* the envp array */ |
| stack_len = ALIGN(stack_len, FLAT_STACK_ALIGN); |
| |
| res = load_flat_file(bprm, &libinfo, 0, &stack_len); |
| if (res < 0) |
| return res; |
| |
| /* Update data segment pointers for all libraries */ |
| for (i = 0; i < MAX_SHARED_LIBS; i++) { |
| if (!libinfo.lib_list[i].loaded) |
| continue; |
| for (j = 0; j < MAX_SHARED_LIBS; j++) { |
| unsigned long val = libinfo.lib_list[j].loaded ? |
| libinfo.lib_list[j].start_data : UNLOADED_LIB; |
| unsigned long __user *p = (unsigned long __user *) |
| libinfo.lib_list[i].start_data; |
| p -= j + 1; |
| if (put_user(val, p)) |
| return -EFAULT; |
| } |
| } |
| |
| install_exec_creds(bprm); |
| |
| set_binfmt(&flat_format); |
| |
| #ifdef CONFIG_MMU |
| res = setup_arg_pages(bprm, STACK_TOP, EXSTACK_DEFAULT); |
| if (!res) |
| res = create_flat_tables(bprm, bprm->p); |
| #else |
| /* Stash our initial stack pointer into the mm structure */ |
| current->mm->start_stack = |
| ((current->mm->context.end_brk + stack_len + 3) & ~3) - 4; |
| pr_debug("sp=%lx\n", current->mm->start_stack); |
| |
| /* copy the arg pages onto the stack */ |
| res = transfer_args_to_stack(bprm, ¤t->mm->start_stack); |
| if (!res) |
| res = create_flat_tables(bprm, current->mm->start_stack); |
| #endif |
| if (res) |
| return res; |
| |
| /* Fake some return addresses to ensure the call chain will |
| * initialise library in order for us. We are required to call |
| * lib 1 first, then 2, ... and finally the main program (id 0). |
| */ |
| start_addr = libinfo.lib_list[0].entry; |
| |
| #ifdef CONFIG_BINFMT_SHARED_FLAT |
| for (i = MAX_SHARED_LIBS-1; i > 0; i--) { |
| if (libinfo.lib_list[i].loaded) { |
| /* Push previos first to call address */ |
| unsigned long __user *sp; |
| current->mm->start_stack -= sizeof(unsigned long); |
| sp = (unsigned long __user *)current->mm->start_stack; |
| __put_user(start_addr, sp); |
| start_addr = libinfo.lib_list[i].entry; |
| } |
| } |
| #endif |
| |
| #ifdef FLAT_PLAT_INIT |
| FLAT_PLAT_INIT(regs); |
| #endif |
| |
| finalize_exec(bprm); |
| pr_debug("start_thread(regs=0x%p, entry=0x%lx, start_stack=0x%lx)\n", |
| regs, start_addr, current->mm->start_stack); |
| start_thread(regs, start_addr, current->mm->start_stack); |
| |
| return 0; |
| } |
| |
| /****************************************************************************/ |
| |
| static int __init init_flat_binfmt(void) |
| { |
| register_binfmt(&flat_format); |
| return 0; |
| } |
| core_initcall(init_flat_binfmt); |
| |
| /****************************************************************************/ |