ARM: report present cpus instead of online CPUs
[linux-2.6.git] / fs / binfmt_elf_fdpic.c
index 364fcfc..30745f4 100644 (file)
@@ -34,6 +34,7 @@
 #include <linux/elf.h>
 #include <linux/elf-fdpic.h>
 #include <linux/elfcore.h>
+#include <linux/coredump.h>
 
 #include <asm/uaccess.h>
 #include <asm/param.h>
@@ -244,8 +245,7 @@ static int load_elf_fdpic_binary(struct linux_binprm *bprm,
                         * mm->dumpable = 0 regardless of the interpreter's
                         * permissions.
                         */
-                       if (file_permission(interpreter, MAY_READ) < 0)
-                               bprm->interp_flags |= BINPRM_FLAGS_ENFORCE_NONDUMP;
+                       would_dump(bprm, interpreter);
 
                        retval = kernel_read(interpreter, 0, bprm->buf,
                                             BINPRM_BUF_SIZE);
@@ -989,10 +989,9 @@ static int elf_fdpic_map_file_constdisp_on_uclinux(
 
                /* clear any space allocated but not loaded */
                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 (clear_user((void *) (seg->addr + phdr->p_filesz),
+                                      phdr->p_memsz - phdr->p_filesz))
+                               return -EFAULT;
                }
 
                if (mm) {
@@ -1004,15 +1003,8 @@ static int elf_fdpic_map_file_constdisp_on_uclinux(
                                }
                        } else if (!mm->start_data) {
                                mm->start_data = seg->addr;
-#ifndef CONFIG_MMU
                                mm->end_data = seg->addr + phdr->p_memsz;
-#endif
                        }
-
-#ifdef CONFIG_MMU
-                       if (seg->addr + phdr->p_memsz > mm->end_data)
-                               mm->end_data = seg->addr + phdr->p_memsz;
-#endif
                }
 
                seg++;
@@ -1033,7 +1025,7 @@ 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, ret;
+       int loop, dvset;
 
        load_addr = params->load_addr;
        delta_vaddr = 0;
@@ -1133,9 +1125,8 @@ 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);
-                       ret = clear_user((void __user *) maddr, disp);
-                       if (ret)
-                               return ret;
+                       if (clear_user((void __user *) maddr, disp))
+                               return -EFAULT;
                        maddr += disp;
                }
 
@@ -1170,19 +1161,17 @@ 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);
-                       ret = clear_user((void __user *) maddr + phdr->p_filesz,
-                                        excess1);
-                       if (ret)
-                               return ret;
+                       if (clear_user((void __user *) maddr + phdr->p_filesz,
+                                      excess1))
+                               return -EFAULT;
                }
 
 #else
                if (excess > 0) {
                        kdebug("clear[%d] ad=%lx sz=%lx",
                               loop, maddr + phdr->p_filesz, excess);
-                       ret = clear_user((void *) maddr + phdr->p_filesz, excess);
-                       if (ret)
-                               return ret;
+                       if (clear_user((void *) maddr + phdr->p_filesz, excess))
+                               return -EFAULT;
                }
 #endif
 
@@ -1216,26 +1205,6 @@ static int elf_fdpic_map_file_by_direct_mmap(struct elf_fdpic_params *params,
 #ifdef CONFIG_ELF_CORE
 
 /*
- * 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) {
-               if (file->f_op->llseek(file, off, SEEK_SET) != off)
-                       return 0;
-       } else {
-               file->f_pos = off;
-       }
-       return 1;
-}
-
-/*
  * Decide whether a segment is worth dumping; default is yes to be
  * sure (missing info is worse than too much; etc).
  * Personally I'd include everything, and use the coredump limit...
@@ -1313,35 +1282,35 @@ static int notesize(struct memelfnote *en)
 
 /* #define DEBUG */
 
-#define DUMP_WRITE(addr, nr)   \
-       do { if (!dump_write(file, (addr), (nr))) return 0; } while(0)
-#define DUMP_SEEK(off) \
-       do { if (!dump_seek(file, (off))) return 0; } while(0)
+#define DUMP_WRITE(addr, nr, foffset)  \
+       do { if (!dump_write(file, (addr), (nr))) return 0; *foffset += (nr); } while(0)
 
-static int writenote(struct memelfnote *men, struct file *file)
+static int alignfile(struct file *file, loff_t *foffset)
 {
-       struct elf_note en;
+       static const char buf[4] = { 0, };
+       DUMP_WRITE(buf, roundup(*foffset, 4) - *foffset, foffset);
+       return 1;
+}
 
+static int writenote(struct memelfnote *men, struct file *file,
+                       loff_t *foffset)
+{
+       struct elf_note en;
        en.n_namesz = strlen(men->name) + 1;
        en.n_descsz = men->datasz;
        en.n_type = men->type;
 
-       DUMP_WRITE(&en, sizeof(en));
-       DUMP_WRITE(men->name, en.n_namesz);
-       /* XXX - cast from long long to long to avoid need for libgcc.a */
-       DUMP_SEEK(roundup((unsigned long)file->f_pos, 4));      /* XXX */
-       DUMP_WRITE(men->data, men->datasz);
-       DUMP_SEEK(roundup((unsigned long)file->f_pos, 4));      /* XXX */
+       DUMP_WRITE(&en, sizeof(en), foffset);
+       DUMP_WRITE(men->name, en.n_namesz, foffset);
+       if (!alignfile(file, foffset))
+               return 0;
+       DUMP_WRITE(men->data, men->datasz, foffset);
+       if (!alignfile(file, foffset))
+               return 0;
 
        return 1;
 }
 #undef DUMP_WRITE
-#undef DUMP_SEEK
-
-#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)
 {
@@ -1524,6 +1493,22 @@ static int elf_dump_thread_status(long signr, struct elf_thread_status *t)
        return sz;
 }
 
+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;
+}
+
 /*
  * dump the segments for an MMU process
  */
@@ -1552,7 +1537,7 @@ static int elf_fdpic_dump_segments(struct file *file, size_t *size,
                                        err = -EIO;
                                kunmap(page);
                                page_cache_release(page);
-                       } else if (!dump_seek(file, file->f_pos + PAGE_SIZE))
+                       } else if (!dump_seek(file, PAGE_SIZE))
                                err = -EFBIG;
                        if (err)
                                goto out;
@@ -1588,6 +1573,17 @@ static int elf_fdpic_dump_segments(struct file *file, size_t *size,
 }
 #endif
 
+static size_t elf_core_vma_data_size(unsigned long mm_flags)
+{
+       struct vm_area_struct *vma;
+       size_t size = 0;
+
+       for (vma = current->mm->mmap; vma; vma = vma->vm_next)
+               if (maydump(vma, mm_flags))
+                       size += vma->vm_end - vma->vm_start;
+       return size;
+}
+
 /*
  * Actual dumper
  *
@@ -1605,7 +1601,7 @@ static int elf_fdpic_core_dump(struct coredump_params *cprm)
        int i;
        struct vm_area_struct *vma;
        struct elfhdr *elf = NULL;
-       loff_t offset = 0, dataoff;
+       loff_t offset = 0, dataoff, foffset;
        int numnote;
        struct memelfnote *notes = NULL;
        struct elf_prstatus *prstatus = NULL;   /* NT_PRSTATUS */
@@ -1618,7 +1614,10 @@ static int elf_fdpic_core_dump(struct coredump_params *cprm)
 #endif
        int thread_status_size = 0;
        elf_addr_t *auxv;
-       unsigned long mm_flags;
+       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.
@@ -1683,12 +1682,18 @@ static int elf_fdpic_core_dump(struct coredump_params *cprm)
        elf_core_copy_regs(&prstatus->pr_reg, cprm->regs);
 
        segs = current->mm->map_count;
-#ifdef ELF_CORE_EXTRA_PHDRS
-       segs += ELF_CORE_EXTRA_PHDRS;
-#endif
+       segs += elf_core_extra_phdrs();
+
+       /* 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;
 
        /* Set up header */
-       fill_elf_fdpic_header(elf, segs + 1);   /* including notes section */
+       fill_elf_fdpic_header(elf, e_phnum);
 
        has_dumped = 1;
        current->flags |= PF_DUMPCORE;
@@ -1727,13 +1732,12 @@ static int elf_fdpic_core_dump(struct coredump_params *cprm)
        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;
                int sz = 0;
 
                for (i = 0; i < numnote; i++)
@@ -1741,20 +1745,38 @@ static int elf_fdpic_core_dump(struct coredump_params *cprm)
 
                sz += thread_status_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));
        }
 
        /* Page-align dumped data */
        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(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 = current->mm->mmap; vma; vma = vma->vm_next) {
@@ -1767,7 +1789,7 @@ static int elf_fdpic_core_dump(struct coredump_params *cprm)
                phdr.p_offset = offset;
                phdr.p_vaddr = vma->vm_start;
                phdr.p_paddr = 0;
-               phdr.p_filesz = maydump(vma, mm_flags) ? sz : 0;
+               phdr.p_filesz = maydump(vma, cprm->mm_flags) ? sz : 0;
                phdr.p_memsz = sz;
                offset += phdr.p_filesz;
                phdr.p_flags = vma->vm_flags & VM_READ ? PF_R : 0;
@@ -1777,16 +1799,18 @@ static int elf_fdpic_core_dump(struct coredump_params *cprm)
                        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 */
        for (i = 0; i < numnote; i++)
-               if (!writenote(notes + i, cprm->file))
+               if (!writenote(notes + i, cprm->file, &foffset))
                        goto end_coredump;
 
        /* write out the thread status notes section */
@@ -1795,20 +1819,27 @@ static int elf_fdpic_core_dump(struct coredump_params *cprm)
                                list_entry(t, struct elf_thread_status, list);
 
                for (i = 0; i < tmp->num_notes; i++)
-                       if (!writenote(&tmp->notes[i], cprm->file))
+                       if (!writenote(&tmp->notes[i], cprm->file, &foffset))
                                goto end_coredump;
        }
 
-       if (!dump_seek(cprm->file, dataoff))
+       if (!dump_seek(cprm->file, dataoff - foffset))
                goto end_coredump;
 
        if (elf_fdpic_dump_segments(cprm->file, &size, &cprm->limit,
-                                   mm_flags) < 0)
+                                   cprm->mm_flags) < 0)
                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;
+       }
 
        if (cprm->file->f_pos != offset) {
                /* Sanity check */
@@ -1826,12 +1857,13 @@ cleanup:
                list_del(tmp);
                kfree(list_entry(tmp, struct elf_thread_status, list));
        }
-
+       kfree(phdr4note);
        kfree(elf);
        kfree(prstatus);
        kfree(psinfo);
        kfree(notes);
        kfree(fpu);
+       kfree(shdr4extnum);
 #ifdef ELF_CORE_COPY_XFPREGS
        kfree(xfpu);
 #endif