xfs: reclaim inodes under a write lock
[safe/jmp/linux-2.6] / fs / binfmt_elf_fdpic.c
index 22baf1b..c57d9ce 100644 (file)
@@ -75,14 +75,14 @@ static int elf_fdpic_map_file_constdisp_on_uclinux(struct elf_fdpic_params *,
 static int elf_fdpic_map_file_by_direct_mmap(struct elf_fdpic_params *,
                                             struct file *, struct mm_struct *);
 
-#if defined(USE_ELF_CORE_DUMP) && defined(CONFIG_ELF_CORE)
-static int elf_fdpic_core_dump(long, struct pt_regs *, struct file *, unsigned long limit);
+#ifdef CONFIG_ELF_CORE
+static int elf_fdpic_core_dump(struct coredump_params *cprm);
 #endif
 
 static struct linux_binfmt elf_fdpic_format = {
        .module         = THIS_MODULE,
        .load_binary    = load_elf_fdpic_binary,
-#if defined(USE_ELF_CORE_DUMP) && defined(CONFIG_ELF_CORE)
+#ifdef CONFIG_ELF_CORE
        .core_dump      = elf_fdpic_core_dump,
 #endif
        .min_coredump   = ELF_EXEC_PAGESIZE,
@@ -168,12 +168,12 @@ static int load_elf_fdpic_binary(struct linux_binprm *bprm,
        struct elf_fdpic_params exec_params, interp_params;
        struct elf_phdr *phdr;
        unsigned long stack_size, entryaddr;
-#ifndef CONFIG_MMU
-       unsigned long fullsize;
-#endif
 #ifdef ELF_FDPIC_PLAT_INIT
        unsigned long dynaddr;
 #endif
+#ifndef CONFIG_MMU
+       unsigned long stack_prot;
+#endif
        struct file *interpreter = NULL; /* to shut gcc up */
        char *interpreter_name = NULL;
        int executable_stack;
@@ -286,20 +286,23 @@ static int load_elf_fdpic_binary(struct linux_binprm *bprm,
        }
 
        stack_size = exec_params.stack_size;
-       if (stack_size < interp_params.stack_size)
-               stack_size = interp_params.stack_size;
-
        if (exec_params.flags & ELF_FDPIC_FLAG_EXEC_STACK)
                executable_stack = EXSTACK_ENABLE_X;
        else if (exec_params.flags & ELF_FDPIC_FLAG_NOEXEC_STACK)
                executable_stack = EXSTACK_DISABLE_X;
-       else if (interp_params.flags & ELF_FDPIC_FLAG_EXEC_STACK)
-               executable_stack = EXSTACK_ENABLE_X;
-       else if (interp_params.flags & ELF_FDPIC_FLAG_NOEXEC_STACK)
-               executable_stack = EXSTACK_DISABLE_X;
        else
                executable_stack = EXSTACK_DEFAULT;
 
+       if (stack_size == 0) {
+               stack_size = interp_params.stack_size;
+               if (interp_params.flags & ELF_FDPIC_FLAG_EXEC_STACK)
+                       executable_stack = EXSTACK_ENABLE_X;
+               else if (interp_params.flags & ELF_FDPIC_FLAG_NOEXEC_STACK)
+                       executable_stack = EXSTACK_DISABLE_X;
+               else
+                       executable_stack = EXSTACK_DEFAULT;
+       }
+
        retval = -ENOEXEC;
        if (stack_size == 0)
                goto error;
@@ -316,6 +319,8 @@ static int load_elf_fdpic_binary(struct linux_binprm *bprm,
         * defunct, deceased, etc. after this point we have to exit via
         * error_kill */
        set_personality(PER_LINUX_FDPIC);
+       if (elf_read_implies_exec(&exec_params.hdr, executable_stack))
+               current->personality |= READ_IMPLIES_EXEC;
        set_binfmt(&elf_fdpic_format);
 
        current->mm->start_code = 0;
@@ -377,10 +382,15 @@ static int load_elf_fdpic_binary(struct linux_binprm *bprm,
        if (stack_size < PAGE_SIZE * 2)
                stack_size = PAGE_SIZE * 2;
 
+       stack_prot = PROT_READ | PROT_WRITE;
+       if (executable_stack == EXSTACK_ENABLE_X ||
+           (executable_stack == EXSTACK_DEFAULT && VM_STACK_FLAGS & VM_EXEC))
+               stack_prot |= PROT_EXEC;
+
        down_write(&current->mm->mmap_sem);
-       current->mm->start_brk = do_mmap(NULL, 0, stack_size,
-                                        PROT_READ | PROT_WRITE | PROT_EXEC,
-                                        MAP_PRIVATE | MAP_ANONYMOUS | MAP_GROWSDOWN,
+       current->mm->start_brk = do_mmap(NULL, 0, stack_size, stack_prot,
+                                        MAP_PRIVATE | MAP_ANONYMOUS |
+                                        MAP_UNINITIALIZED | MAP_GROWSDOWN,
                                         0);
 
        if (IS_ERR_VALUE(current->mm->start_brk)) {
@@ -390,11 +400,6 @@ static int load_elf_fdpic_binary(struct linux_binprm *bprm,
                goto error_kill;
        }
 
-       /* expand the stack mapping to use up the entire allocation granule */
-       fullsize = kobjsize((char *) current->mm->start_brk);
-       if (!IS_ERR_VALUE(do_mremap(current->mm->start_brk, stack_size,
-                                   fullsize, 0, 0)))
-               stack_size = fullsize;
        up_write(&current->mm->mmap_sem);
 
        current->mm->brk = current->mm->start_brk;
@@ -980,9 +985,12 @@ static int elf_fdpic_map_file_constdisp_on_uclinux(
                        params->elfhdr_addr = seg->addr;
 
                /* clear any space allocated but not loaded */
-               if (phdr->p_filesz < phdr->p_memsz)
-                       clear_user((void *) (seg->addr + phdr->p_filesz),
-                                  phdr->p_memsz - phdr->p_filesz);
+               if (phdr->p_filesz < phdr->p_memsz) {
+                       ret = clear_user((void *) (seg->addr + phdr->p_filesz),
+                                        phdr->p_memsz - phdr->p_filesz);
+                       if (ret)
+                               return ret;
+               }
 
                if (mm) {
                        if (phdr->p_flags & PF_X) {
@@ -1022,7 +1030,7 @@ static int elf_fdpic_map_file_by_direct_mmap(struct elf_fdpic_params *params,
        struct elf32_fdpic_loadseg *seg;
        struct elf32_phdr *phdr;
        unsigned long load_addr, delta_vaddr;
-       int loop, dvset;
+       int loop, dvset, ret;
 
        load_addr = params->load_addr;
        delta_vaddr = 0;
@@ -1122,7 +1130,9 @@ static int elf_fdpic_map_file_by_direct_mmap(struct elf_fdpic_params *params,
                 * PT_LOAD */
                if (prot & PROT_WRITE && disp > 0) {
                        kdebug("clear[%d] ad=%lx sz=%lx", loop, maddr, disp);
-                       clear_user((void __user *) maddr, disp);
+                       ret = clear_user((void __user *) maddr, disp);
+                       if (ret)
+                               return ret;
                        maddr += disp;
                }
 
@@ -1157,15 +1167,19 @@ static int elf_fdpic_map_file_by_direct_mmap(struct elf_fdpic_params *params,
                if (prot & PROT_WRITE && excess1 > 0) {
                        kdebug("clear[%d] ad=%lx sz=%lx",
                               loop, maddr + phdr->p_filesz, excess1);
-                       clear_user((void __user *) maddr + phdr->p_filesz,
-                                  excess1);
+                       ret = clear_user((void __user *) maddr + phdr->p_filesz,
+                                        excess1);
+                       if (ret)
+                               return ret;
                }
 
 #else
                if (excess > 0) {
                        kdebug("clear[%d] ad=%lx sz=%lx",
                               loop, maddr + phdr->p_filesz, excess);
-                       clear_user((void *) maddr + phdr->p_filesz, excess);
+                       ret = clear_user((void *) maddr + phdr->p_filesz, excess);
+                       if (ret)
+                               return ret;
                }
 #endif
 
@@ -1196,7 +1210,7 @@ static int elf_fdpic_map_file_by_direct_mmap(struct elf_fdpic_params *params,
  *
  * Modelled on fs/binfmt_elf.c core dumper
  */
-#if defined(USE_ELF_CORE_DUMP) && defined(CONFIG_ELF_CORE)
+#ifdef CONFIG_ELF_CORE
 
 /*
  * These are the only things you should do on a core-file: use only these
@@ -1321,11 +1335,9 @@ static int writenote(struct memelfnote *men, struct file *file)
 #undef DUMP_WRITE
 #undef DUMP_SEEK
 
-#define DUMP_WRITE(addr, nr)   \
-       if ((size += (nr)) > limit || !dump_write(file, (addr), (nr))) \
-               goto end_coredump;
-#define DUMP_SEEK(off) \
-       if (!dump_seek(file, (off))) \
+#define DUMP_WRITE(addr, nr)                           \
+       if ((size += (nr)) > cprm->limit ||             \
+           !dump_write(cprm->file, (addr), (nr)))      \
                goto end_coredump;
 
 static inline void fill_elf_fdpic_header(struct elfhdr *elf, int segs)
@@ -1386,8 +1398,10 @@ static void fill_prstatus(struct elf_prstatus *prstatus,
        prstatus->pr_info.si_signo = prstatus->pr_cursig = signr;
        prstatus->pr_sigpend = p->pending.signal.sig[0];
        prstatus->pr_sighold = p->blocked.sig[0];
+       rcu_read_lock();
+       prstatus->pr_ppid = task_pid_vnr(rcu_dereference(p->real_parent));
+       rcu_read_unlock();
        prstatus->pr_pid = task_pid_vnr(p);
-       prstatus->pr_ppid = task_pid_vnr(p->parent);
        prstatus->pr_pgrp = task_pgrp_vnr(p);
        prstatus->pr_sid = task_session_vnr(p);
        if (thread_group_leader(p)) {
@@ -1431,8 +1445,10 @@ static int fill_psinfo(struct elf_prpsinfo *psinfo, struct task_struct *p,
                        psinfo->pr_psargs[i] = ' ';
        psinfo->pr_psargs[len] = 0;
 
+       rcu_read_lock();
+       psinfo->pr_ppid = task_pid_vnr(rcu_dereference(p->real_parent));
+       rcu_read_unlock();
        psinfo->pr_pid = task_pid_vnr(p);
-       psinfo->pr_ppid = task_pid_vnr(p->parent);
        psinfo->pr_pgrp = task_pgrp_vnr(p);
        psinfo->pr_sid = task_session_vnr(p);
 
@@ -1513,6 +1529,7 @@ static int elf_fdpic_dump_segments(struct file *file, size_t *size,
                           unsigned long *limit, unsigned long mm_flags)
 {
        struct vm_area_struct *vma;
+       int err = 0;
 
        for (vma = current->mm->mmap; vma; vma = vma->vm_next) {
                unsigned long addr;
@@ -1520,43 +1537,26 @@ static int elf_fdpic_dump_segments(struct file *file, size_t *size,
                if (!maydump(vma, mm_flags))
                        continue;
 
-               for (addr = vma->vm_start;
-                    addr < vma->vm_end;
-                    addr += PAGE_SIZE
-                    ) {
-                       struct vm_area_struct *vma;
-                       struct page *page;
-
-                       if (get_user_pages(current, current->mm, addr, 1, 0, 1,
-                                          &page, &vma) <= 0) {
-                               DUMP_SEEK(file->f_pos + PAGE_SIZE);
-                       }
-                       else if (page == ZERO_PAGE(0)) {
-                               page_cache_release(page);
-                               DUMP_SEEK(file->f_pos + PAGE_SIZE);
-                       }
-                       else {
-                               void *kaddr;
-
-                               flush_cache_page(vma, addr, page_to_pfn(page));
-                               kaddr = kmap(page);
-                               if ((*size += PAGE_SIZE) > *limit ||
-                                   !dump_write(file, kaddr, PAGE_SIZE)
-                                   ) {
-                                       kunmap(page);
-                                       page_cache_release(page);
-                                       return -EIO;
-                               }
+               for (addr = vma->vm_start; addr < vma->vm_end;
+                                                       addr += PAGE_SIZE) {
+                       struct page *page = get_dump_page(addr);
+                       if (page) {
+                               void *kaddr = kmap(page);
+                               *size += PAGE_SIZE;
+                               if (*size > *limit)
+                                       err = -EFBIG;
+                               else if (!dump_write(file, kaddr, PAGE_SIZE))
+                                       err = -EIO;
                                kunmap(page);
                                page_cache_release(page);
-                       }
+                       } else if (!dump_seek(file, file->f_pos + PAGE_SIZE))
+                               err = -EFBIG;
+                       if (err)
+                               goto out;
                }
        }
-
-       return 0;
-
-end_coredump:
-       return -EFBIG;
+out:
+       return err;
 }
 #endif
 
@@ -1592,8 +1592,7 @@ static int elf_fdpic_dump_segments(struct file *file, size_t *size,
  * and then they are actually written out.  If we run out of core limit
  * we just truncate.
  */
-static int elf_fdpic_core_dump(long signr, struct pt_regs *regs,
-                              struct file *file, unsigned long limit)
+static int elf_fdpic_core_dump(struct coredump_params *cprm)
 {
 #define        NUM_NOTES       6
        int has_dumped = 0;
@@ -1652,7 +1651,7 @@ static int elf_fdpic_core_dump(long signr, struct pt_regs *regs,
                goto cleanup;
 #endif
 
-       if (signr) {
+       if (cprm->signr) {
                struct core_thread *ct;
                struct elf_thread_status *tmp;
 
@@ -1671,14 +1670,14 @@ static int elf_fdpic_core_dump(long signr, struct pt_regs *regs,
                        int sz;
 
                        tmp = list_entry(t, struct elf_thread_status, list);
-                       sz = elf_dump_thread_status(signr, tmp);
+                       sz = elf_dump_thread_status(cprm->signr, tmp);
                        thread_status_size += sz;
                }
        }
 
        /* now collect the dump for the current */
-       fill_prstatus(prstatus, current, signr);
-       elf_core_copy_regs(&prstatus->pr_reg, regs);
+       fill_prstatus(prstatus, current, cprm->signr);
+       elf_core_copy_regs(&prstatus->pr_reg, cprm->regs);
 
        segs = current->mm->map_count;
 #ifdef ELF_CORE_EXTRA_PHDRS
@@ -1713,7 +1712,7 @@ static int elf_fdpic_core_dump(long signr, struct pt_regs *regs,
 
        /* Try to dump the FPU. */
        if ((prstatus->pr_fpvalid =
-            elf_core_copy_task_fpregs(current, regs, fpu)))
+            elf_core_copy_task_fpregs(current, cprm->regs, fpu)))
                fill_note(notes + numnote++,
                          "CORE", NT_PRFPREG, sizeof(*fpu), fpu);
 #ifdef ELF_CORE_COPY_XFPREGS
@@ -1784,7 +1783,7 @@ static int elf_fdpic_core_dump(long signr, struct pt_regs *regs,
 
        /* write out the notes section */
        for (i = 0; i < numnote; i++)
-               if (!writenote(notes + i, file))
+               if (!writenote(notes + i, cprm->file))
                        goto end_coredump;
 
        /* write out the thread status notes section */
@@ -1793,24 +1792,26 @@ static int elf_fdpic_core_dump(long signr, struct pt_regs *regs,
                                list_entry(t, struct elf_thread_status, list);
 
                for (i = 0; i < tmp->num_notes; i++)
-                       if (!writenote(&tmp->notes[i], file))
+                       if (!writenote(&tmp->notes[i], cprm->file))
                                goto end_coredump;
        }
 
-       DUMP_SEEK(dataoff);
+       if (!dump_seek(cprm->file, dataoff))
+               goto end_coredump;
 
-       if (elf_fdpic_dump_segments(file, &size, &limit, mm_flags) < 0)
+       if (elf_fdpic_dump_segments(cprm->file, &size, &cprm->limit,
+                                   mm_flags) < 0)
                goto end_coredump;
 
 #ifdef ELF_CORE_WRITE_EXTRA_DATA
        ELF_CORE_WRITE_EXTRA_DATA;
 #endif
 
-       if (file->f_pos != offset) {
+       if (cprm->file->f_pos != offset) {
                /* Sanity check */
                printk(KERN_WARNING
                       "elf_core_dump: file->f_pos (%lld) != offset (%lld)\n",
-                      file->f_pos, offset);
+                      cprm->file->f_pos, offset);
        }
 
 end_coredump:
@@ -1835,4 +1836,4 @@ cleanup:
 #undef NUM_NOTES
 }
 
-#endif         /* USE_ELF_CORE_DUMP */
+#endif         /* CONFIG_ELF_CORE */