Merge git://git.kernel.org/pub/scm/linux/kernel/git/rusty/linux-2.6-for-linus

* git://git.kernel.org/pub/scm/linux/kernel/git/rusty/linux-2.6-for-linus:
  module: don't call percpu_modfree on NULL pointer.
  module: fix memory leak when load fails after srcversion/version allocated
  module: preferred way to use MODULE_AUTHOR
  param: allow whitespace as kernel parameter separator
  module: reduce string table for loaded modules (v2)
  module: reduce symbol table for loaded modules (v2)
This commit is contained in:
Linus Torvalds 2009-09-24 09:01:05 -07:00
commit 2c9871de0a
3 changed files with 165 additions and 18 deletions

View file

@ -128,7 +128,10 @@ extern struct module __this_module;
*/ */
#define MODULE_LICENSE(_license) MODULE_INFO(license, _license) #define MODULE_LICENSE(_license) MODULE_INFO(license, _license)
/* Author, ideally of form NAME[, NAME]*[ and NAME] */ /*
* Author(s), use "Name <email>" or just "Name", for multiple
* authors use multiple MODULE_AUTHOR() statements/lines.
*/
#define MODULE_AUTHOR(_author) MODULE_INFO(author, _author) #define MODULE_AUTHOR(_author) MODULE_INFO(author, _author)
/* What your module does. */ /* What your module does. */
@ -308,10 +311,14 @@ struct module
#endif #endif
#ifdef CONFIG_KALLSYMS #ifdef CONFIG_KALLSYMS
/* We keep the symbol and string tables for kallsyms. */ /*
Elf_Sym *symtab; * We keep the symbol and string tables for kallsyms.
unsigned int num_symtab; * The core_* fields below are temporary, loader-only (they
char *strtab; * could really be discarded after module init).
*/
Elf_Sym *symtab, *core_symtab;
unsigned int num_symtab, core_num_syms;
char *strtab, *core_strtab;
/* Section attributes */ /* Section attributes */
struct module_sect_attrs *sect_attrs; struct module_sect_attrs *sect_attrs;

View file

@ -1797,6 +1797,17 @@ static void setup_modinfo(struct module *mod, Elf_Shdr *sechdrs,
} }
} }
static void free_modinfo(struct module *mod)
{
struct module_attribute *attr;
int i;
for (i = 0; (attr = modinfo_attrs[i]); i++) {
if (attr->free)
attr->free(mod);
}
}
#ifdef CONFIG_KALLSYMS #ifdef CONFIG_KALLSYMS
/* lookup symbol in given range of kernel_symbols */ /* lookup symbol in given range of kernel_symbols */
@ -1862,13 +1873,93 @@ static char elf_type(const Elf_Sym *sym,
return '?'; return '?';
} }
static void add_kallsyms(struct module *mod, static bool is_core_symbol(const Elf_Sym *src, const Elf_Shdr *sechdrs,
unsigned int shnum)
{
const Elf_Shdr *sec;
if (src->st_shndx == SHN_UNDEF
|| src->st_shndx >= shnum
|| !src->st_name)
return false;
sec = sechdrs + src->st_shndx;
if (!(sec->sh_flags & SHF_ALLOC)
#ifndef CONFIG_KALLSYMS_ALL
|| !(sec->sh_flags & SHF_EXECINSTR)
#endif
|| (sec->sh_entsize & INIT_OFFSET_MASK))
return false;
return true;
}
static unsigned long layout_symtab(struct module *mod,
Elf_Shdr *sechdrs, Elf_Shdr *sechdrs,
unsigned int symindex, unsigned int symindex,
unsigned int strindex, unsigned int strindex,
const char *secstrings) const Elf_Ehdr *hdr,
const char *secstrings,
unsigned long *pstroffs,
unsigned long *strmap)
{ {
unsigned int i; unsigned long symoffs;
Elf_Shdr *symsect = sechdrs + symindex;
Elf_Shdr *strsect = sechdrs + strindex;
const Elf_Sym *src;
const char *strtab;
unsigned int i, nsrc, ndst;
/* Put symbol section at end of init part of module. */
symsect->sh_flags |= SHF_ALLOC;
symsect->sh_entsize = get_offset(mod, &mod->init_size, symsect,
symindex) | INIT_OFFSET_MASK;
DEBUGP("\t%s\n", secstrings + symsect->sh_name);
src = (void *)hdr + symsect->sh_offset;
nsrc = symsect->sh_size / sizeof(*src);
strtab = (void *)hdr + strsect->sh_offset;
for (ndst = i = 1; i < nsrc; ++i, ++src)
if (is_core_symbol(src, sechdrs, hdr->e_shnum)) {
unsigned int j = src->st_name;
while(!__test_and_set_bit(j, strmap) && strtab[j])
++j;
++ndst;
}
/* Append room for core symbols at end of core part. */
symoffs = ALIGN(mod->core_size, symsect->sh_addralign ?: 1);
mod->core_size = symoffs + ndst * sizeof(Elf_Sym);
/* Put string table section at end of init part of module. */
strsect->sh_flags |= SHF_ALLOC;
strsect->sh_entsize = get_offset(mod, &mod->init_size, strsect,
strindex) | INIT_OFFSET_MASK;
DEBUGP("\t%s\n", secstrings + strsect->sh_name);
/* Append room for core symbols' strings at end of core part. */
*pstroffs = mod->core_size;
__set_bit(0, strmap);
mod->core_size += bitmap_weight(strmap, strsect->sh_size);
return symoffs;
}
static void add_kallsyms(struct module *mod,
Elf_Shdr *sechdrs,
unsigned int shnum,
unsigned int symindex,
unsigned int strindex,
unsigned long symoffs,
unsigned long stroffs,
const char *secstrings,
unsigned long *strmap)
{
unsigned int i, ndst;
const Elf_Sym *src;
Elf_Sym *dst;
char *s;
mod->symtab = (void *)sechdrs[symindex].sh_addr; mod->symtab = (void *)sechdrs[symindex].sh_addr;
mod->num_symtab = sechdrs[symindex].sh_size / sizeof(Elf_Sym); mod->num_symtab = sechdrs[symindex].sh_size / sizeof(Elf_Sym);
@ -1878,13 +1969,44 @@ static void add_kallsyms(struct module *mod,
for (i = 0; i < mod->num_symtab; i++) for (i = 0; i < mod->num_symtab; i++)
mod->symtab[i].st_info mod->symtab[i].st_info
= elf_type(&mod->symtab[i], sechdrs, secstrings, mod); = elf_type(&mod->symtab[i], sechdrs, secstrings, mod);
mod->core_symtab = dst = mod->module_core + symoffs;
src = mod->symtab;
*dst = *src;
for (ndst = i = 1; i < mod->num_symtab; ++i, ++src) {
if (!is_core_symbol(src, sechdrs, shnum))
continue;
dst[ndst] = *src;
dst[ndst].st_name = bitmap_weight(strmap, dst[ndst].st_name);
++ndst;
}
mod->core_num_syms = ndst;
mod->core_strtab = s = mod->module_core + stroffs;
for (*s = 0, i = 1; i < sechdrs[strindex].sh_size; ++i)
if (test_bit(i, strmap))
*++s = mod->strtab[i];
} }
#else #else
static inline void add_kallsyms(struct module *mod, static inline unsigned long layout_symtab(struct module *mod,
Elf_Shdr *sechdrs, Elf_Shdr *sechdrs,
unsigned int symindex, unsigned int symindex,
unsigned int strindex, unsigned int strindex,
const char *secstrings) const Elf_Hdr *hdr,
const char *secstrings,
unsigned long *pstroffs,
unsigned long *strmap)
{
}
static inline void add_kallsyms(struct module *mod,
Elf_Shdr *sechdrs,
unsigned int shnum,
unsigned int symindex,
unsigned int strindex,
unsigned long symoffs,
unsigned long stroffs,
const char *secstrings,
const unsigned long *strmap)
{ {
} }
#endif /* CONFIG_KALLSYMS */ #endif /* CONFIG_KALLSYMS */
@ -1959,6 +2081,9 @@ static noinline struct module *load_module(void __user *umod,
struct module *mod; struct module *mod;
long err = 0; long err = 0;
void *percpu = NULL, *ptr = NULL; /* Stops spurious gcc warning */ void *percpu = NULL, *ptr = NULL; /* Stops spurious gcc warning */
#ifdef CONFIG_KALLSYMS
unsigned long symoffs, stroffs, *strmap;
#endif
mm_segment_t old_fs; mm_segment_t old_fs;
DEBUGP("load_module: umod=%p, len=%lu, uargs=%p\n", DEBUGP("load_module: umod=%p, len=%lu, uargs=%p\n",
@ -2040,11 +2165,6 @@ static noinline struct module *load_module(void __user *umod,
/* Don't keep modinfo and version sections. */ /* Don't keep modinfo and version sections. */
sechdrs[infoindex].sh_flags &= ~(unsigned long)SHF_ALLOC; sechdrs[infoindex].sh_flags &= ~(unsigned long)SHF_ALLOC;
sechdrs[versindex].sh_flags &= ~(unsigned long)SHF_ALLOC; sechdrs[versindex].sh_flags &= ~(unsigned long)SHF_ALLOC;
#ifdef CONFIG_KALLSYMS
/* Keep symbol and string tables for decoding later. */
sechdrs[symindex].sh_flags |= SHF_ALLOC;
sechdrs[strindex].sh_flags |= SHF_ALLOC;
#endif
/* Check module struct version now, before we try to use module. */ /* Check module struct version now, before we try to use module. */
if (!check_modstruct_version(sechdrs, versindex, mod)) { if (!check_modstruct_version(sechdrs, versindex, mod)) {
@ -2080,6 +2200,13 @@ static noinline struct module *load_module(void __user *umod,
goto free_hdr; goto free_hdr;
} }
strmap = kzalloc(BITS_TO_LONGS(sechdrs[strindex].sh_size)
* sizeof(long), GFP_KERNEL);
if (!strmap) {
err = -ENOMEM;
goto free_mod;
}
if (find_module(mod->name)) { if (find_module(mod->name)) {
err = -EEXIST; err = -EEXIST;
goto free_mod; goto free_mod;
@ -2109,6 +2236,8 @@ static noinline struct module *load_module(void __user *umod,
this is done generically; there doesn't appear to be any this is done generically; there doesn't appear to be any
special cases for the architectures. */ special cases for the architectures. */
layout_sections(mod, hdr, sechdrs, secstrings); layout_sections(mod, hdr, sechdrs, secstrings);
symoffs = layout_symtab(mod, sechdrs, symindex, strindex, hdr,
secstrings, &stroffs, strmap);
/* Do the allocs. */ /* Do the allocs. */
ptr = module_alloc_update_bounds(mod->core_size); ptr = module_alloc_update_bounds(mod->core_size);
@ -2313,7 +2442,10 @@ static noinline struct module *load_module(void __user *umod,
percpu_modcopy(mod->percpu, (void *)sechdrs[pcpuindex].sh_addr, percpu_modcopy(mod->percpu, (void *)sechdrs[pcpuindex].sh_addr,
sechdrs[pcpuindex].sh_size); sechdrs[pcpuindex].sh_size);
add_kallsyms(mod, sechdrs, symindex, strindex, secstrings); add_kallsyms(mod, sechdrs, hdr->e_shnum, symindex, strindex,
symoffs, stroffs, secstrings, strmap);
kfree(strmap);
strmap = NULL;
if (!mod->taints) { if (!mod->taints) {
struct _ddebug *debug; struct _ddebug *debug;
@ -2385,13 +2517,14 @@ static noinline struct module *load_module(void __user *umod,
synchronize_sched(); synchronize_sched();
module_arch_cleanup(mod); module_arch_cleanup(mod);
cleanup: cleanup:
free_modinfo(mod);
kobject_del(&mod->mkobj.kobj); kobject_del(&mod->mkobj.kobj);
kobject_put(&mod->mkobj.kobj); kobject_put(&mod->mkobj.kobj);
free_unload: free_unload:
module_unload_free(mod); module_unload_free(mod);
#if defined(CONFIG_MODULE_UNLOAD) && defined(CONFIG_SMP) #if defined(CONFIG_MODULE_UNLOAD) && defined(CONFIG_SMP)
free_init:
percpu_modfree(mod->refptr); percpu_modfree(mod->refptr);
free_init:
#endif #endif
module_free(mod, mod->module_init); module_free(mod, mod->module_init);
free_core: free_core:
@ -2402,6 +2535,7 @@ static noinline struct module *load_module(void __user *umod,
percpu_modfree(percpu); percpu_modfree(percpu);
free_mod: free_mod:
kfree(args); kfree(args);
kfree(strmap);
free_hdr: free_hdr:
vfree(hdr); vfree(hdr);
return ERR_PTR(err); return ERR_PTR(err);
@ -2491,6 +2625,11 @@ SYSCALL_DEFINE3(init_module, void __user *, umod,
/* Drop initial reference. */ /* Drop initial reference. */
module_put(mod); module_put(mod);
trim_init_extable(mod); trim_init_extable(mod);
#ifdef CONFIG_KALLSYMS
mod->num_symtab = mod->core_num_syms;
mod->symtab = mod->core_symtab;
mod->strtab = mod->core_strtab;
#endif
module_free(mod, mod->module_init); module_free(mod, mod->module_init);
mod->module_init = NULL; mod->module_init = NULL;
mod->init_size = 0; mod->init_size = 0;

View file

@ -23,6 +23,7 @@
#include <linux/device.h> #include <linux/device.h>
#include <linux/err.h> #include <linux/err.h>
#include <linux/slab.h> #include <linux/slab.h>
#include <linux/ctype.h>
#if 0 #if 0
#define DEBUGP printk #define DEBUGP printk
@ -87,7 +88,7 @@ static char *next_arg(char *args, char **param, char **val)
} }
for (i = 0; args[i]; i++) { for (i = 0; args[i]; i++) {
if (args[i] == ' ' && !in_quote) if (isspace(args[i]) && !in_quote)
break; break;
if (equals == 0) { if (equals == 0) {
if (args[i] == '=') if (args[i] == '=')
@ -121,7 +122,7 @@ static char *next_arg(char *args, char **param, char **val)
next = args + i; next = args + i;
/* Chew up trailing spaces. */ /* Chew up trailing spaces. */
while (*next == ' ') while (isspace(*next))
next++; next++;
return next; return next;
} }
@ -138,7 +139,7 @@ int parse_args(const char *name,
DEBUGP("Parsing ARGS: %s\n", args); DEBUGP("Parsing ARGS: %s\n", args);
/* Chew leading spaces */ /* Chew leading spaces */
while (*args == ' ') while (isspace(*args))
args++; args++;
while (*args) { while (*args) {