diff options
| -rw-r--r-- | fs/proc/kcore.c | 350 |
1 files changed, 141 insertions, 209 deletions
diff --git a/fs/proc/kcore.c b/fs/proc/kcore.c index dc34642bbdb7..808ef9afd084 100644 --- a/fs/proc/kcore.c +++ b/fs/proc/kcore.c @@ -49,15 +49,6 @@ static struct proc_dir_entry *proc_root_kcore; #define kc_offset_to_vaddr(o) ((o) + PAGE_OFFSET) #endif -/* An ELF note in memory */ -struct memelfnote -{ - const char *name; - int type; - unsigned int datasz; - void *data; -}; - static LIST_HEAD(kclist_head); static DECLARE_RWSEM(kclist_lock); static int kcore_need_update = 1; @@ -73,7 +64,8 @@ void __init kclist_add(struct kcore_list *new, void *addr, size_t size, list_add_tail(&new->list, &kclist_head); } -static size_t get_kcore_size(int *nphdr, size_t *elf_buflen) +static size_t get_kcore_size(int *nphdr, size_t *phdrs_len, size_t *notes_len, + size_t *data_offset) { size_t try, size; struct kcore_list *m; @@ -87,15 +79,15 @@ static size_t get_kcore_size(int *nphdr, size_t *elf_buflen) size = try; *nphdr = *nphdr + 1; } - *elf_buflen = sizeof(struct elfhdr) + - (*nphdr + 2)*sizeof(struct elf_phdr) + - 3 * ((sizeof(struct elf_note)) + - roundup(sizeof(CORE_STR), 4)) + - roundup(sizeof(struct elf_prstatus), 4) + - roundup(sizeof(struct elf_prpsinfo), 4) + - roundup(arch_task_struct_size, 4); - *elf_buflen = PAGE_ALIGN(*elf_buflen); - return size + *elf_buflen; + + *phdrs_len = *nphdr * sizeof(struct elf_phdr); + *notes_len = (3 * (sizeof(struct elf_note) + ALIGN(sizeof(CORE_STR), 4)) + + ALIGN(sizeof(struct elf_prstatus), 4) + + ALIGN(sizeof(struct elf_prpsinfo), 4) + + ALIGN(arch_task_struct_size, 4)); + *data_offset = PAGE_ALIGN(sizeof(struct elfhdr) + *phdrs_len + + *notes_len); + return *data_offset + size; } #ifdef CONFIG_HIGHMEM @@ -241,7 +233,7 @@ static int kcore_update_ram(void) LIST_HEAD(list); LIST_HEAD(garbage); int nphdr; - size_t size; + size_t phdrs_len, notes_len, data_offset; struct kcore_list *tmp, *pos; int ret = 0; @@ -263,7 +255,8 @@ static int kcore_update_ram(void) } list_splice_tail(&list, &kclist_head); - proc_root_kcore->size = get_kcore_size(&nphdr, &size); + proc_root_kcore->size = get_kcore_size(&nphdr, &phdrs_len, ¬es_len, + &data_offset); out: up_write(&kclist_lock); @@ -274,228 +267,168 @@ out: return ret; } -/*****************************************************************************/ -/* - * determine size of ELF note - */ -static int notesize(struct memelfnote *en) +static void append_kcore_note(char *notes, size_t *i, const char *name, + unsigned int type, const void *desc, + size_t descsz) { - int sz; - - sz = sizeof(struct elf_note); - sz += roundup((strlen(en->name) + 1), 4); - sz += roundup(en->datasz, 4); - - return sz; -} /* end notesize() */ - -/*****************************************************************************/ -/* - * store a note in the header buffer - */ -static char *storenote(struct memelfnote *men, char *bufp) -{ - struct elf_note en; - -#define DUMP_WRITE(addr,nr) do { memcpy(bufp,addr,nr); bufp += nr; } while(0) - - 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 */ - bufp = (char*) roundup((unsigned long)bufp,4); - DUMP_WRITE(men->data, men->datasz); - bufp = (char*) roundup((unsigned long)bufp,4); - -#undef DUMP_WRITE - - return bufp; -} /* end storenote() */ - -/* - * store an ELF coredump header in the supplied buffer - * nphdr is the number of elf_phdr to insert - */ -static void elf_kcore_store_hdr(char *bufp, int nphdr, int dataoff) -{ - struct elf_prstatus prstatus; /* NT_PRSTATUS */ - struct elf_prpsinfo prpsinfo; /* NT_PRPSINFO */ - struct elf_phdr *nhdr, *phdr; - struct elfhdr *elf; - struct memelfnote notes[3]; - off_t offset = 0; - struct kcore_list *m; - - /* setup ELF header */ - elf = (struct elfhdr *) bufp; - bufp += sizeof(struct elfhdr); - offset += sizeof(struct elfhdr); - memcpy(elf->e_ident, ELFMAG, SELFMAG); - elf->e_ident[EI_CLASS] = ELF_CLASS; - elf->e_ident[EI_DATA] = ELF_DATA; - elf->e_ident[EI_VERSION]= EV_CURRENT; - elf->e_ident[EI_OSABI] = ELF_OSABI; - memset(elf->e_ident+EI_PAD, 0, EI_NIDENT-EI_PAD); - elf->e_type = ET_CORE; - elf->e_machine = ELF_ARCH; - elf->e_version = EV_CURRENT; - elf->e_entry = 0; - elf->e_phoff = sizeof(struct elfhdr); - elf->e_shoff = 0; - elf->e_flags = ELF_CORE_EFLAGS; - elf->e_ehsize = sizeof(struct elfhdr); - elf->e_phentsize= sizeof(struct elf_phdr); - elf->e_phnum = nphdr; - elf->e_shentsize= 0; - elf->e_shnum = 0; - elf->e_shstrndx = 0; - - /* setup ELF PT_NOTE program header */ - nhdr = (struct elf_phdr *) bufp; - bufp += sizeof(struct elf_phdr); - offset += sizeof(struct elf_phdr); - nhdr->p_type = PT_NOTE; - nhdr->p_offset = 0; - nhdr->p_vaddr = 0; - nhdr->p_paddr = 0; - nhdr->p_filesz = 0; - nhdr->p_memsz = 0; - nhdr->p_flags = 0; - nhdr->p_align = 0; - - /* setup ELF PT_LOAD program header for every area */ - list_for_each_entry(m, &kclist_head, list) { - phdr = (struct elf_phdr *) bufp; - bufp += sizeof(struct elf_phdr); - offset += sizeof(struct elf_phdr); - - phdr->p_type = PT_LOAD; - phdr->p_flags = PF_R|PF_W|PF_X; - phdr->p_offset = kc_vaddr_to_offset(m->addr) + dataoff; - phdr->p_vaddr = (size_t)m->addr; - if (m->type == KCORE_RAM) - phdr->p_paddr = __pa(m->addr); - else if (m->type == KCORE_TEXT) - phdr->p_paddr = __pa_symbol(m->addr); - else - phdr->p_paddr = (elf_addr_t)-1; - phdr->p_filesz = phdr->p_memsz = m->size; - phdr->p_align = PAGE_SIZE; - } - - /* - * Set up the notes in similar form to SVR4 core dumps made - * with info from their /proc. - */ - nhdr->p_offset = offset; - - /* set up the process status */ - notes[0].name = CORE_STR; - notes[0].type = NT_PRSTATUS; - notes[0].datasz = sizeof(struct elf_prstatus); - notes[0].data = &prstatus; - - memset(&prstatus, 0, sizeof(struct elf_prstatus)); - - nhdr->p_filesz = notesize(¬es[0]); - bufp = storenote(¬es[0], bufp); - - /* set up the process info */ - notes[1].name = CORE_STR; - notes[1].type = NT_PRPSINFO; - notes[1].datasz = sizeof(struct elf_prpsinfo); - notes[1].data = &prpsinfo; - - memset(&prpsinfo, 0, sizeof(struct elf_prpsinfo)); - prpsinfo.pr_state = 0; - prpsinfo.pr_sname = 'R'; - prpsinfo.pr_zomb = 0; - - strcpy(prpsinfo.pr_fname, "vmlinux"); - strlcpy(prpsinfo.pr_psargs, saved_command_line, sizeof(prpsinfo.pr_psargs)); - - nhdr->p_filesz += notesize(¬es[1]); - bufp = storenote(¬es[1], bufp); - - /* set up the task structure */ - notes[2].name = CORE_STR; - notes[2].type = NT_TASKSTRUCT; - notes[2].datasz = arch_task_struct_size; - notes[2].data = current; - - nhdr->p_filesz += notesize(¬es[2]); - bufp = storenote(¬es[2], bufp); - -} /* end elf_kcore_store_hdr() */ + struct elf_note *note = (struct elf_note *)¬es[*i]; + + note->n_namesz = strlen(name) + 1; + note->n_descsz = descsz; + note->n_type = type; + *i += sizeof(*note); + memcpy(¬es[*i], name, note->n_namesz); + *i = ALIGN(*i + note->n_namesz, 4); + memcpy(¬es[*i], desc, descsz); + *i = ALIGN(*i + descsz, 4); +} -/*****************************************************************************/ -/* - * read from the ELF header and then kernel memory - */ static ssize_t read_kcore(struct file *file, char __user *buffer, size_t buflen, loff_t *fpos) { char *buf = file->private_data; - size_t size, tsz; - size_t elf_buflen; + size_t phdrs_offset, notes_offset, data_offset; + size_t phdrs_len, notes_len; + struct kcore_list *m; + size_t tsz; int nphdr; unsigned long start; size_t orig_buflen = buflen; int ret = 0; down_read(&kclist_lock); - size = get_kcore_size(&nphdr, &elf_buflen); - if (buflen == 0 || *fpos >= size) - goto out; + get_kcore_size(&nphdr, &phdrs_len, ¬es_len, &data_offset); + phdrs_offset = sizeof(struct elfhdr); + notes_offset = phdrs_offset + phdrs_len; + + /* ELF file header. */ + if (buflen && *fpos < sizeof(struct elfhdr)) { + struct elfhdr ehdr = { + .e_ident = { + [EI_MAG0] = ELFMAG0, + [EI_MAG1] = ELFMAG1, + [EI_MAG2] = ELFMAG2, + [EI_MAG3] = ELFMAG3, + [EI_CLASS] = ELF_CLASS, + [EI_DATA] = ELF_DATA, + [EI_VERSION] = EV_CURRENT, + [EI_OSABI] = ELF_OSABI, + }, + .e_type = ET_CORE, + .e_machine = ELF_ARCH, + .e_version = EV_CURRENT, + .e_phoff = sizeof(struct elfhdr), + .e_flags = ELF_CORE_EFLAGS, + .e_ehsize = sizeof(struct elfhdr), + .e_phentsize = sizeof(struct elf_phdr), + .e_phnum = nphdr, + }; + + tsz = min_t(size_t, buflen, sizeof(struct elfhdr) - *fpos); + if (copy_to_user(buffer, (char *)&ehdr + *fpos, tsz)) { + ret = -EFAULT; + goto out; + } - /* trim buflen to not go beyond EOF */ - if (buflen > size - *fpos) - buflen = size - *fpos; + buffer += tsz; + buflen -= tsz; + *fpos += tsz; + } - /* construct an ELF core header if we'll need some of it */ - if (*fpos < elf_buflen) { - char * elf_buf; + /* ELF program headers. */ + if (buflen && *fpos < phdrs_offset + phdrs_len) { + struct elf_phdr *phdrs, *phdr; - tsz = elf_buflen - *fpos; - if (buflen < tsz) - tsz = buflen; - elf_buf = kzalloc(elf_buflen, GFP_KERNEL); - if (!elf_buf) { + phdrs = kzalloc(phdrs_len, GFP_KERNEL); + if (!phdrs) { ret = -ENOMEM; goto out; } - elf_kcore_store_hdr(elf_buf, nphdr, elf_buflen); - if (copy_to_user(buffer, elf_buf + *fpos, tsz)) { - kfree(elf_buf); + + phdrs[0].p_type = PT_NOTE; + phdrs[0].p_offset = notes_offset; + phdrs[0].p_filesz = notes_len; + + phdr = &phdrs[1]; + list_for_each_entry(m, &kclist_head, list) { + phdr->p_type = PT_LOAD; + phdr->p_flags = PF_R | PF_W | PF_X; + phdr->p_offset = kc_vaddr_to_offset(m->addr) + data_offset; + phdr->p_vaddr = (size_t)m->addr; + if (m->type == KCORE_RAM) + phdr->p_paddr = __pa(m->addr); + else if (m->type == KCORE_TEXT) + phdr->p_paddr = __pa_symbol(m->addr); + else + phdr->p_paddr = (elf_addr_t)-1; + phdr->p_filesz = phdr->p_memsz = m->size; + phdr->p_align = PAGE_SIZE; + phdr++; + } + + tsz = min_t(size_t, buflen, phdrs_offset + phdrs_len - *fpos); + if (copy_to_user(buffer, (char *)phdrs + *fpos - phdrs_offset, + tsz)) { + kfree(phdrs); ret = -EFAULT; goto out; } - kfree(elf_buf); + kfree(phdrs); + + buffer += tsz; buflen -= tsz; *fpos += tsz; - buffer += tsz; + } + + /* ELF note segment. */ + if (buflen && *fpos < notes_offset + notes_len) { + struct elf_prstatus prstatus = {}; + struct elf_prpsinfo prpsinfo = { + .pr_sname = 'R', + .pr_fname = "vmlinux", + }; + char *notes; + size_t i = 0; + + strlcpy(prpsinfo.pr_psargs, saved_command_line, + sizeof(prpsinfo.pr_psargs)); + + notes = kzalloc(notes_len, GFP_KERNEL); + if (!notes) { + ret = -ENOMEM; + goto out; + } + + append_kcore_note(notes, &i, CORE_STR, NT_PRSTATUS, &prstatus, + sizeof(prstatus)); + append_kcore_note(notes, &i, CORE_STR, NT_PRPSINFO, &prpsinfo, + sizeof(prpsinfo)); + append_kcore_note(notes, &i, CORE_STR, NT_TASKSTRUCT, current, + arch_task_struct_size); - /* leave now if filled buffer already */ - if (buflen == 0) + tsz = min_t(size_t, buflen, notes_offset + notes_len - *fpos); + if (copy_to_user(buffer, notes + *fpos - notes_offset, tsz)) { + kfree(notes); + ret = -EFAULT; goto out; + } + kfree(notes); + + buffer += tsz; + buflen -= tsz; + *fpos += tsz; } /* * Check to see if our file offset matches with any of * the addresses in the elf_phdr on our list. */ - start = kc_offset_to_vaddr(*fpos - elf_buflen); + start = kc_offset_to_vaddr(*fpos - data_offset); if ((tsz = (PAGE_SIZE - (start & ~PAGE_MASK))) > buflen) tsz = buflen; - - while (buflen) { - struct kcore_list *m; + while (buflen) { list_for_each_entry(m, &kclist_head, list) { if (start >= m->addr && start < (m->addr+m->size)) break; @@ -557,7 +490,6 @@ out: return orig_buflen - buflen; } - static int open_kcore(struct inode *inode, struct file *filp) { if (!capable(CAP_SYS_RAWIO)) |