diff options
Diffstat (limited to 'fs/binfmt_elf_fdpic.c')
| -rw-r--r-- | fs/binfmt_elf_fdpic.c | 181 |
1 files changed, 112 insertions, 69 deletions
diff --git a/fs/binfmt_elf_fdpic.c b/fs/binfmt_elf_fdpic.c index 364fcfc..2c32d00 100644 --- a/fs/binfmt_elf_fdpic.c +++ b/fs/binfmt_elf_fdpic.c @@ -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> @@ -1216,26 +1217,6 @@ 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 +1294,35 @@ 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 +1505,22 @@ 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 +1549,7 @@ 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 +1585,17 @@ 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->vm_next) + if (maydump(vma, mm_flags)) + size += vma->vm_end - vma->vm_start; + return size; +} + /* * Actual dumper * @@ -1605,7 +1613,7 @@ 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 +1626,10 @@ 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 +1694,18 @@ 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 +1744,12 @@ 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 +1757,38 @@ 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 +1801,7 @@ 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 +1811,18 @@ 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 +1831,27 @@ 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 */ @@ -1826,7 +1869,7 @@ cleanup: list_del(tmp); kfree(list_entry(tmp, struct elf_thread_status, list)); } - + kfree(phdr4note); kfree(elf); kfree(prstatus); kfree(psinfo); |