X-Git-Url: http://ftp.safe.ca/?a=blobdiff_plain;f=fs%2Fbinfmt_elf.c;h=535e763ab1a61e56ef5d25d725dc4f39eb899a49;hb=94d09a98cdb163be12fb5c76841fa295f0bee22a;hp=b9b3bb51b1e485ff0caa0b7555d468804b552b9a;hpb=0cf062d0ffa33d491e2695b0d298ccf9cbb58d3d;p=safe%2Fjmp%2Flinux-2.6 diff --git a/fs/binfmt_elf.c b/fs/binfmt_elf.c index b9b3bb5..535e763 100644 --- a/fs/binfmt_elf.c +++ b/fs/binfmt_elf.c @@ -31,6 +31,7 @@ #include #include #include +#include #include #include #include @@ -44,8 +45,8 @@ static unsigned long elf_map(struct file *, unsigned long, struct elf_phdr *, * If we don't support core dumping, then supply a NULL so we * don't even try. */ -#if defined(USE_ELF_CORE_DUMP) && defined(CONFIG_ELF_CORE) -static int elf_core_dump(long signr, struct pt_regs *regs, struct file *file, unsigned long limit); +#ifdef CONFIG_ELF_CORE +static int elf_core_dump(struct coredump_params *cprm); #else #define elf_core_dump NULL #endif @@ -662,27 +663,6 @@ static int load_elf_binary(struct linux_binprm *bprm, struct pt_regs *regs) if (elf_interpreter[elf_ppnt->p_filesz - 1] != '\0') goto out_free_interp; - /* - * The early SET_PERSONALITY here is so that the lookup - * for the interpreter happens in the namespace of the - * to-be-execed image. SET_PERSONALITY can select an - * alternate root. - * - * However, SET_PERSONALITY is NOT allowed to switch - * this task into the new images's memory mapping - * policy - that is, TASK_SIZE must still evaluate to - * that which is appropriate to the execing application. - * This is because exit_mmap() needs to have TASK_SIZE - * evaluate to the size of the old image. - * - * So if (say) a 64-bit application is execing a 32-bit - * application it is the architecture's responsibility - * to defer changing the value of TASK_SIZE until the - * switch really is going to happen - do this in - * flush_thread(). - akpm - */ - SET_PERSONALITY(loc->elf_ex); - interpreter = open_exec(elf_interpreter); retval = PTR_ERR(interpreter); if (IS_ERR(interpreter)) @@ -730,9 +710,6 @@ static int load_elf_binary(struct linux_binprm *bprm, struct pt_regs *regs) /* Verify the interpreter has a valid arch */ if (!elf_check_arch(&loc->interp_elf_ex)) goto out_free_dentry; - } else { - /* Executables without an interpreter also need a personality */ - SET_PERSONALITY(loc->elf_ex); } /* Flush all traces of the currently running executable */ @@ -752,7 +729,8 @@ static int load_elf_binary(struct linux_binprm *bprm, struct pt_regs *regs) if (!(current->personality & ADDR_NO_RANDOMIZE) && randomize_va_space) current->flags |= PF_RANDOMIZE; - arch_pick_mmap_layout(current->mm); + + setup_new_exec(bprm); /* Do this so that we can load the interpreter, if need be. We will change some of these later */ @@ -767,7 +745,7 @@ static int load_elf_binary(struct linux_binprm *bprm, struct pt_regs *regs) current->mm->start_stack = bprm->p; - /* Now we do a little grungy work by mmaping the ELF image into + /* Now we do a little grungy work by mmapping the ELF image into the correct location in memory. */ for(i = 0, elf_ppnt = elf_phdata; i < loc->elf_ex.e_phnum; i++, elf_ppnt++) { @@ -1101,48 +1079,13 @@ out: return error; } -/* - * Note that some platforms still use traditional core dumps and not - * the ELF core dump. Each platform can select it as appropriate. - */ -#if defined(USE_ELF_CORE_DUMP) && defined(CONFIG_ELF_CORE) - +#ifdef CONFIG_ELF_CORE /* * ELF core dumper * * Modelled on fs/exec.c:aout_core_dump() * Jeremy Fitzhardinge */ -/* - * These are the only things you should do on a core-file: use only these - * functions to write out all the necessary info. - */ -static int dump_write(struct file *file, const void *addr, int nr) -{ - return file->f_op->write(file, addr, nr, &file->f_pos) == nr; -} - -static int dump_seek(struct file *file, loff_t off) -{ - if (file->f_op->llseek && file->f_op->llseek != no_llseek) { - if (file->f_op->llseek(file, off, SEEK_CUR) < 0) - return 0; - } else { - char *buf = (char *)get_zeroed_page(GFP_KERNEL); - if (!buf) - return 0; - while (off > 0) { - unsigned long n = off; - if (n > PAGE_SIZE) - n = PAGE_SIZE; - if (!dump_write(file, buf, n)) - return 0; - off -= n; - } - free_page((unsigned long)buf); - } - return 1; -} /* * Decide what to dump of a segment, part, all or none. @@ -1277,10 +1220,6 @@ static int writenote(struct memelfnote *men, struct file *file, } #undef DUMP_WRITE -#define DUMP_WRITE(addr, nr) \ - if ((size += (nr)) > limit || !dump_write(file, (addr), (nr))) \ - goto end_coredump; - static void fill_elf_header(struct elfhdr *elf, int segs, u16 machine, u32 flags, u8 osabi) { @@ -1899,6 +1838,34 @@ static struct vm_area_struct *next_vma(struct vm_area_struct *this_vma, return gate_vma; } +static void fill_extnum_info(struct elfhdr *elf, struct elf_shdr *shdr4extnum, + elf_addr_t e_shoff, int segs) +{ + elf->e_shoff = e_shoff; + elf->e_shentsize = sizeof(*shdr4extnum); + elf->e_shnum = 1; + elf->e_shstrndx = SHN_UNDEF; + + memset(shdr4extnum, 0, sizeof(*shdr4extnum)); + + shdr4extnum->sh_type = SHT_NULL; + shdr4extnum->sh_size = elf->e_shnum; + shdr4extnum->sh_link = elf->e_shstrndx; + shdr4extnum->sh_info = segs; +} + +static size_t elf_core_vma_data_size(struct vm_area_struct *gate_vma, + unsigned long mm_flags) +{ + struct vm_area_struct *vma; + size_t size = 0; + + for (vma = first_vma(current, gate_vma); vma != NULL; + vma = next_vma(vma, gate_vma)) + size += vma_dump_size(vma, mm_flags); + return size; +} + /* * Actual dumper * @@ -1906,7 +1873,7 @@ static struct vm_area_struct *next_vma(struct vm_area_struct *this_vma, * and then they are actually written out. If we run out of core limit * we just truncate. */ -static int elf_core_dump(long signr, struct pt_regs *regs, struct file *file, unsigned long limit) +static int elf_core_dump(struct coredump_params *cprm) { int has_dumped = 0; mm_segment_t fs; @@ -1915,8 +1882,11 @@ static int elf_core_dump(long signr, struct pt_regs *regs, struct file *file, un struct vm_area_struct *vma, *gate_vma; struct elfhdr *elf = NULL; loff_t offset = 0, dataoff, foffset; - unsigned long mm_flags; struct elf_note_info info; + struct elf_phdr *phdr4note = NULL; + struct elf_shdr *shdr4extnum = NULL; + Elf_Half e_phnum; + elf_addr_t e_shoff; /* * We no longer stop all VM operations. @@ -1939,20 +1909,25 @@ static int elf_core_dump(long signr, struct pt_regs *regs, struct file *file, un * Please check DEFAULT_MAX_MAP_COUNT definition when you modify here. */ segs = current->mm->map_count; -#ifdef ELF_CORE_EXTRA_PHDRS - segs += ELF_CORE_EXTRA_PHDRS; -#endif + segs += elf_core_extra_phdrs(); gate_vma = get_gate_vma(current); if (gate_vma != NULL) segs++; + /* for notes section */ + segs++; + + /* If segs > PN_XNUM(0xffff), then e_phnum overflows. To avoid + * this, kernel supports extended numbering. Have a look at + * include/linux/elf.h for further information. */ + e_phnum = segs > PN_XNUM ? PN_XNUM : segs; + /* * Collect all the non-memory information about the process for the * notes. This also sets up the file header. */ - if (!fill_note_info(elf, segs + 1, /* including notes section */ - &info, signr, regs)) + if (!fill_note_info(elf, e_phnum, &info, cprm->signr, cprm->regs)) goto cleanup; has_dumped = 1; @@ -1961,31 +1936,47 @@ static int elf_core_dump(long signr, struct pt_regs *regs, struct file *file, un fs = get_fs(); set_fs(KERNEL_DS); - DUMP_WRITE(elf, sizeof(*elf)); offset += sizeof(*elf); /* Elf header */ - offset += (segs + 1) * sizeof(struct elf_phdr); /* Program headers */ + offset += segs * sizeof(struct elf_phdr); /* Program headers */ foffset = offset; /* Write notes phdr entry */ { - struct elf_phdr phdr; size_t sz = get_note_info_size(&info); sz += elf_coredump_extra_notes_size(); - fill_elf_note_phdr(&phdr, sz, offset); + phdr4note = kmalloc(sizeof(*phdr4note), GFP_KERNEL); + if (!phdr4note) + goto end_coredump; + + fill_elf_note_phdr(phdr4note, sz, offset); offset += sz; - DUMP_WRITE(&phdr, sizeof(phdr)); } dataoff = offset = roundup(offset, ELF_EXEC_PAGESIZE); - /* - * We must use the same mm->flags while dumping core to avoid - * inconsistency between the program headers and bodies, otherwise an - * unusable core file can be generated. - */ - mm_flags = current->mm->flags; + offset += elf_core_vma_data_size(gate_vma, cprm->mm_flags); + offset += elf_core_extra_data_size(); + e_shoff = offset; + + if (e_phnum == PN_XNUM) { + shdr4extnum = kmalloc(sizeof(*shdr4extnum), GFP_KERNEL); + if (!shdr4extnum) + goto end_coredump; + fill_extnum_info(elf, shdr4extnum, e_shoff, segs); + } + + offset = dataoff; + + size += sizeof(*elf); + if (size > cprm->limit || !dump_write(cprm->file, elf, sizeof(*elf))) + goto end_coredump; + + size += sizeof(*phdr4note); + if (size > cprm->limit + || !dump_write(cprm->file, phdr4note, sizeof(*phdr4note))) + goto end_coredump; /* Write program headers for segments dump */ for (vma = first_vma(current, gate_vma); vma != NULL; @@ -1996,7 +1987,7 @@ static int elf_core_dump(long signr, struct pt_regs *regs, struct file *file, un phdr.p_offset = offset; phdr.p_vaddr = vma->vm_start; phdr.p_paddr = 0; - phdr.p_filesz = vma_dump_size(vma, mm_flags); + phdr.p_filesz = vma_dump_size(vma, cprm->mm_flags); phdr.p_memsz = vma->vm_end - vma->vm_start; offset += phdr.p_filesz; phdr.p_flags = vma->vm_flags & VM_READ ? PF_R : 0; @@ -2006,22 +1997,24 @@ static int elf_core_dump(long signr, struct pt_regs *regs, struct file *file, un phdr.p_flags |= PF_X; phdr.p_align = ELF_EXEC_PAGESIZE; - DUMP_WRITE(&phdr, sizeof(phdr)); + size += sizeof(phdr); + if (size > cprm->limit + || !dump_write(cprm->file, &phdr, sizeof(phdr))) + goto end_coredump; } -#ifdef ELF_CORE_WRITE_EXTRA_PHDRS - ELF_CORE_WRITE_EXTRA_PHDRS; -#endif + if (!elf_core_write_extra_phdrs(cprm->file, offset, &size, cprm->limit)) + goto end_coredump; /* write out the notes section */ - if (!write_note_info(&info, file, &foffset)) + if (!write_note_info(&info, cprm->file, &foffset)) goto end_coredump; - if (elf_coredump_extra_notes_write(file, &foffset)) + if (elf_coredump_extra_notes_write(cprm->file, &foffset)) goto end_coredump; /* Align to page */ - if (!dump_seek(file, dataoff - foffset)) + if (!dump_seek(cprm->file, dataoff - foffset)) goto end_coredump; for (vma = first_vma(current, gate_vma); vma != NULL; @@ -2029,7 +2022,7 @@ static int elf_core_dump(long signr, struct pt_regs *regs, struct file *file, un unsigned long addr; unsigned long end; - end = vma->vm_start + vma_dump_size(vma, mm_flags); + end = vma->vm_start + vma_dump_size(vma, cprm->mm_flags); for (addr = vma->vm_start; addr < end; addr += PAGE_SIZE) { struct page *page; @@ -2038,32 +2031,42 @@ static int elf_core_dump(long signr, struct pt_regs *regs, struct file *file, un page = get_dump_page(addr); if (page) { void *kaddr = kmap(page); - stop = ((size += PAGE_SIZE) > limit) || - !dump_write(file, kaddr, PAGE_SIZE); + stop = ((size += PAGE_SIZE) > cprm->limit) || + !dump_write(cprm->file, kaddr, + PAGE_SIZE); kunmap(page); page_cache_release(page); } else - stop = !dump_seek(file, PAGE_SIZE); + stop = !dump_seek(cprm->file, PAGE_SIZE); if (stop) goto end_coredump; } } -#ifdef ELF_CORE_WRITE_EXTRA_DATA - ELF_CORE_WRITE_EXTRA_DATA; -#endif + if (!elf_core_write_extra_data(cprm->file, &size, cprm->limit)) + goto end_coredump; + + if (e_phnum == PN_XNUM) { + size += sizeof(*shdr4extnum); + if (size > cprm->limit + || !dump_write(cprm->file, shdr4extnum, + sizeof(*shdr4extnum))) + goto end_coredump; + } end_coredump: set_fs(fs); cleanup: free_note_info(&info); + kfree(shdr4extnum); + kfree(phdr4note); kfree(elf); out: return has_dumped; } -#endif /* USE_ELF_CORE_DUMP */ +#endif /* CONFIG_ELF_CORE */ static int __init init_elf_binfmt(void) {