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-rw-r--r--kernel/module.c336
1 files changed, 203 insertions, 133 deletions
diff --git a/kernel/module.c b/kernel/module.c
index 5f80478b746d..d8b5605132a0 100644
--- a/kernel/module.c
+++ b/kernel/module.c
@@ -70,6 +70,9 @@ static DECLARE_WAIT_QUEUE_HEAD(module_wq);
static BLOCKING_NOTIFIER_HEAD(module_notify_list);
+/* Bounds of module allocation, for speeding __module_text_address */
+static unsigned long module_addr_min = -1UL, module_addr_max = 0;
+
int register_module_notifier(struct notifier_block * nb)
{
return blocking_notifier_chain_register(&module_notify_list, nb);
@@ -134,17 +137,19 @@ extern const struct kernel_symbol __start___ksymtab_gpl[];
extern const struct kernel_symbol __stop___ksymtab_gpl[];
extern const struct kernel_symbol __start___ksymtab_gpl_future[];
extern const struct kernel_symbol __stop___ksymtab_gpl_future[];
-extern const struct kernel_symbol __start___ksymtab_unused[];
-extern const struct kernel_symbol __stop___ksymtab_unused[];
-extern const struct kernel_symbol __start___ksymtab_unused_gpl[];
-extern const struct kernel_symbol __stop___ksymtab_unused_gpl[];
extern const struct kernel_symbol __start___ksymtab_gpl_future[];
extern const struct kernel_symbol __stop___ksymtab_gpl_future[];
extern const unsigned long __start___kcrctab[];
extern const unsigned long __start___kcrctab_gpl[];
extern const unsigned long __start___kcrctab_gpl_future[];
+#ifdef CONFIG_UNUSED_SYMBOLS
+extern const struct kernel_symbol __start___ksymtab_unused[];
+extern const struct kernel_symbol __stop___ksymtab_unused[];
+extern const struct kernel_symbol __start___ksymtab_unused_gpl[];
+extern const struct kernel_symbol __stop___ksymtab_unused_gpl[];
extern const unsigned long __start___kcrctab_unused[];
extern const unsigned long __start___kcrctab_unused_gpl[];
+#endif
#ifndef CONFIG_MODVERSIONS
#define symversion(base, idx) NULL
@@ -152,156 +157,186 @@ extern const unsigned long __start___kcrctab_unused_gpl[];
#define symversion(base, idx) ((base != NULL) ? ((base) + (idx)) : NULL)
#endif
-/* lookup symbol in given range of kernel_symbols */
-static const struct kernel_symbol *lookup_symbol(const char *name,
- const struct kernel_symbol *start,
- const struct kernel_symbol *stop)
-{
- const struct kernel_symbol *ks = start;
- for (; ks < stop; ks++)
- if (strcmp(ks->name, name) == 0)
- return ks;
- return NULL;
-}
-
-static bool always_ok(bool gplok, bool warn, const char *name)
-{
- return true;
-}
-
-static bool printk_unused_warning(bool gplok, bool warn, const char *name)
-{
- if (warn) {
- printk(KERN_WARNING "Symbol %s is marked as UNUSED, "
- "however this module is using it.\n", name);
- printk(KERN_WARNING
- "This symbol will go away in the future.\n");
- printk(KERN_WARNING
- "Please evalute if this is the right api to use and if "
- "it really is, submit a report the linux kernel "
- "mailinglist together with submitting your code for "
- "inclusion.\n");
- }
- return true;
-}
-
-static bool gpl_only_unused_warning(bool gplok, bool warn, const char *name)
-{
- if (!gplok)
- return false;
- return printk_unused_warning(gplok, warn, name);
-}
-
-static bool gpl_only(bool gplok, bool warn, const char *name)
-{
- return gplok;
-}
-
-static bool warn_if_not_gpl(bool gplok, bool warn, const char *name)
-{
- if (!gplok && warn) {
- printk(KERN_WARNING "Symbol %s is being used "
- "by a non-GPL module, which will not "
- "be allowed in the future\n", name);
- printk(KERN_WARNING "Please see the file "
- "Documentation/feature-removal-schedule.txt "
- "in the kernel source tree for more details.\n");
- }
- return true;
-}
-
struct symsearch {
const struct kernel_symbol *start, *stop;
const unsigned long *crcs;
- bool (*check)(bool gplok, bool warn, const char *name);
+ enum {
+ NOT_GPL_ONLY,
+ GPL_ONLY,
+ WILL_BE_GPL_ONLY,
+ } licence;
+ bool unused;
};
-/* Look through this array of symbol tables for a symbol match which
- * passes the check function. */
-static const struct kernel_symbol *search_symarrays(const struct symsearch *arr,
- unsigned int num,
- const char *name,
- bool gplok,
- bool warn,
- const unsigned long **crc)
+static bool each_symbol_in_section(const struct symsearch *arr,
+ unsigned int arrsize,
+ struct module *owner,
+ bool (*fn)(const struct symsearch *syms,
+ struct module *owner,
+ unsigned int symnum, void *data),
+ void *data)
{
- unsigned int i;
- const struct kernel_symbol *ks;
+ unsigned int i, j;
- for (i = 0; i < num; i++) {
- ks = lookup_symbol(name, arr[i].start, arr[i].stop);
- if (!ks || !arr[i].check(gplok, warn, name))
- continue;
-
- if (crc)
- *crc = symversion(arr[i].crcs, ks - arr[i].start);
- return ks;
+ for (j = 0; j < arrsize; j++) {
+ for (i = 0; i < arr[j].stop - arr[j].start; i++)
+ if (fn(&arr[j], owner, i, data))
+ return true;
}
- return NULL;
+
+ return false;
}
-/* Find a symbol, return value, (optional) crc and (optional) module
- * which owns it */
-static unsigned long find_symbol(const char *name,
- struct module **owner,
- const unsigned long **crc,
- bool gplok,
- bool warn)
+/* Returns true as soon as fn returns true, otherwise false. */
+static bool each_symbol(bool (*fn)(const struct symsearch *arr,
+ struct module *owner,
+ unsigned int symnum, void *data),
+ void *data)
{
struct module *mod;
- const struct kernel_symbol *ks;
const struct symsearch arr[] = {
{ __start___ksymtab, __stop___ksymtab, __start___kcrctab,
- always_ok },
+ NOT_GPL_ONLY, false },
{ __start___ksymtab_gpl, __stop___ksymtab_gpl,
- __start___kcrctab_gpl, gpl_only },
+ __start___kcrctab_gpl,
+ GPL_ONLY, false },
{ __start___ksymtab_gpl_future, __stop___ksymtab_gpl_future,
- __start___kcrctab_gpl_future, warn_if_not_gpl },
+ __start___kcrctab_gpl_future,
+ WILL_BE_GPL_ONLY, false },
+#ifdef CONFIG_UNUSED_SYMBOLS
{ __start___ksymtab_unused, __stop___ksymtab_unused,
- __start___kcrctab_unused, printk_unused_warning },
+ __start___kcrctab_unused,
+ NOT_GPL_ONLY, true },
{ __start___ksymtab_unused_gpl, __stop___ksymtab_unused_gpl,
- __start___kcrctab_unused_gpl, gpl_only_unused_warning },
+ __start___kcrctab_unused_gpl,
+ GPL_ONLY, true },
+#endif
};
- /* Core kernel first. */
- ks = search_symarrays(arr, ARRAY_SIZE(arr), name, gplok, warn, crc);
- if (ks) {
- if (owner)
- *owner = NULL;
- return ks->value;
- }
+ if (each_symbol_in_section(arr, ARRAY_SIZE(arr), NULL, fn, data))
+ return true;
- /* Now try modules. */
list_for_each_entry(mod, &modules, list) {
struct symsearch arr[] = {
{ mod->syms, mod->syms + mod->num_syms, mod->crcs,
- always_ok },
+ NOT_GPL_ONLY, false },
{ mod->gpl_syms, mod->gpl_syms + mod->num_gpl_syms,
- mod->gpl_crcs, gpl_only },
+ mod->gpl_crcs,
+ GPL_ONLY, false },
{ mod->gpl_future_syms,
mod->gpl_future_syms + mod->num_gpl_future_syms,
- mod->gpl_future_crcs, warn_if_not_gpl },
+ mod->gpl_future_crcs,
+ WILL_BE_GPL_ONLY, false },
+#ifdef CONFIG_UNUSED_SYMBOLS
{ mod->unused_syms,
mod->unused_syms + mod->num_unused_syms,
- mod->unused_crcs, printk_unused_warning },
+ mod->unused_crcs,
+ NOT_GPL_ONLY, true },
{ mod->unused_gpl_syms,
mod->unused_gpl_syms + mod->num_unused_gpl_syms,
- mod->unused_gpl_crcs, gpl_only_unused_warning },
+ mod->unused_gpl_crcs,
+ GPL_ONLY, true },
+#endif
};
- ks = search_symarrays(arr, ARRAY_SIZE(arr),
- name, gplok, warn, crc);
- if (ks) {
- if (owner)
- *owner = mod;
- return ks->value;
+ if (each_symbol_in_section(arr, ARRAY_SIZE(arr), mod, fn, data))
+ return true;
+ }
+ return false;
+}
+
+struct find_symbol_arg {
+ /* Input */
+ const char *name;
+ bool gplok;
+ bool warn;
+
+ /* Output */
+ struct module *owner;
+ const unsigned long *crc;
+ unsigned long value;
+};
+
+static bool find_symbol_in_section(const struct symsearch *syms,
+ struct module *owner,
+ unsigned int symnum, void *data)
+{
+ struct find_symbol_arg *fsa = data;
+
+ if (strcmp(syms->start[symnum].name, fsa->name) != 0)
+ return false;
+
+ if (!fsa->gplok) {
+ if (syms->licence == GPL_ONLY)
+ return false;
+ if (syms->licence == WILL_BE_GPL_ONLY && fsa->warn) {
+ printk(KERN_WARNING "Symbol %s is being used "
+ "by a non-GPL module, which will not "
+ "be allowed in the future\n", fsa->name);
+ printk(KERN_WARNING "Please see the file "
+ "Documentation/feature-removal-schedule.txt "
+ "in the kernel source tree for more details.\n");
}
}
+#ifdef CONFIG_UNUSED_SYMBOLS
+ if (syms->unused && fsa->warn) {
+ printk(KERN_WARNING "Symbol %s is marked as UNUSED, "
+ "however this module is using it.\n", fsa->name);
+ printk(KERN_WARNING
+ "This symbol will go away in the future.\n");
+ printk(KERN_WARNING
+ "Please evalute if this is the right api to use and if "
+ "it really is, submit a report the linux kernel "
+ "mailinglist together with submitting your code for "
+ "inclusion.\n");
+ }
+#endif
+
+ fsa->owner = owner;
+ fsa->crc = symversion(syms->crcs, symnum);
+ fsa->value = syms->start[symnum].value;
+ return true;
+}
+
+/* Find a symbol, return value, (optional) crc and (optional) module
+ * which owns it */
+static unsigned long find_symbol(const char *name,
+ struct module **owner,
+ const unsigned long **crc,
+ bool gplok,
+ bool warn)
+{
+ struct find_symbol_arg fsa;
+
+ fsa.name = name;
+ fsa.gplok = gplok;
+ fsa.warn = warn;
+
+ if (each_symbol(find_symbol_in_section, &fsa)) {
+ if (owner)
+ *owner = fsa.owner;
+ if (crc)
+ *crc = fsa.crc;
+ return fsa.value;
+ }
+
DEBUGP("Failed to find symbol %s\n", name);
return -ENOENT;
}
+/* lookup symbol in given range of kernel_symbols */
+static const struct kernel_symbol *lookup_symbol(const char *name,
+ const struct kernel_symbol *start,
+ const struct kernel_symbol *stop)
+{
+ const struct kernel_symbol *ks = start;
+ for (; ks < stop; ks++)
+ if (strcmp(ks->name, name) == 0)
+ return ks;
+ return NULL;
+}
+
/* Search for module by name: must hold module_mutex. */
static struct module *find_module(const char *name)
{
@@ -639,8 +674,8 @@ static int __try_stop_module(void *_sref)
{
struct stopref *sref = _sref;
- /* If it's not unused, quit unless we are told to block. */
- if ((sref->flags & O_NONBLOCK) && module_refcount(sref->mod) != 0) {
+ /* If it's not unused, quit unless we're forcing. */
+ if (module_refcount(sref->mod) != 0) {
if (!(*sref->forced = try_force_unload(sref->flags)))
return -EWOULDBLOCK;
}
@@ -652,9 +687,16 @@ static int __try_stop_module(void *_sref)
static int try_stop_module(struct module *mod, int flags, int *forced)
{
- struct stopref sref = { mod, flags, forced };
+ if (flags & O_NONBLOCK) {
+ struct stopref sref = { mod, flags, forced };
- return stop_machine_run(__try_stop_module, &sref, NR_CPUS);
+ return stop_machine_run(__try_stop_module, &sref, NR_CPUS);
+ } else {
+ /* We don't need to stop the machine for this. */
+ mod->state = MODULE_STATE_GOING;
+ synchronize_sched();
+ return 0;
+ }
}
unsigned int module_refcount(struct module *mod)
@@ -1445,8 +1487,10 @@ static int verify_export_symbols(struct module *mod)
{ mod->syms, mod->num_syms },
{ mod->gpl_syms, mod->num_gpl_syms },
{ mod->gpl_future_syms, mod->num_gpl_future_syms },
+#ifdef CONFIG_UNUSED_SYMBOLS
{ mod->unused_syms, mod->num_unused_syms },
{ mod->unused_gpl_syms, mod->num_unused_gpl_syms },
+#endif
};
for (i = 0; i < ARRAY_SIZE(arr); i++) {
@@ -1526,7 +1570,7 @@ static int simplify_symbols(Elf_Shdr *sechdrs,
}
/* Update size with this section: return offset. */
-static long get_offset(unsigned long *size, Elf_Shdr *sechdr)
+static long get_offset(unsigned int *size, Elf_Shdr *sechdr)
{
long ret;
@@ -1738,6 +1782,20 @@ static inline void add_kallsyms(struct module *mod,
}
#endif /* CONFIG_KALLSYMS */
+static void *module_alloc_update_bounds(unsigned long size)
+{
+ void *ret = module_alloc(size);
+
+ if (ret) {
+ /* Update module bounds. */
+ if ((unsigned long)ret < module_addr_min)
+ module_addr_min = (unsigned long)ret;
+ if ((unsigned long)ret + size > module_addr_max)
+ module_addr_max = (unsigned long)ret + size;
+ }
+ return ret;
+}
+
/* Allocate and load the module: note that size of section 0 is always
zero, and we rely on this for optional sections. */
static struct module *load_module(void __user *umod,
@@ -1764,10 +1822,12 @@ static struct module *load_module(void __user *umod,
unsigned int gplfutureindex;
unsigned int gplfuturecrcindex;
unsigned int unwindex = 0;
+#ifdef CONFIG_UNUSED_SYMBOLS
unsigned int unusedindex;
unsigned int unusedcrcindex;
unsigned int unusedgplindex;
unsigned int unusedgplcrcindex;
+#endif
unsigned int markersindex;
unsigned int markersstringsindex;
struct module *mod;
@@ -1850,13 +1910,15 @@ static struct module *load_module(void __user *umod,
exportindex = find_sec(hdr, sechdrs, secstrings, "__ksymtab");
gplindex = find_sec(hdr, sechdrs, secstrings, "__ksymtab_gpl");
gplfutureindex = find_sec(hdr, sechdrs, secstrings, "__ksymtab_gpl_future");
- unusedindex = find_sec(hdr, sechdrs, secstrings, "__ksymtab_unused");
- unusedgplindex = find_sec(hdr, sechdrs, secstrings, "__ksymtab_unused_gpl");
crcindex = find_sec(hdr, sechdrs, secstrings, "__kcrctab");
gplcrcindex = find_sec(hdr, sechdrs, secstrings, "__kcrctab_gpl");
gplfuturecrcindex = find_sec(hdr, sechdrs, secstrings, "__kcrctab_gpl_future");
+#ifdef CONFIG_UNUSED_SYMBOLS
+ unusedindex = find_sec(hdr, sechdrs, secstrings, "__ksymtab_unused");
+ unusedgplindex = find_sec(hdr, sechdrs, secstrings, "__ksymtab_unused_gpl");
unusedcrcindex = find_sec(hdr, sechdrs, secstrings, "__kcrctab_unused");
unusedgplcrcindex = find_sec(hdr, sechdrs, secstrings, "__kcrctab_unused_gpl");
+#endif
setupindex = find_sec(hdr, sechdrs, secstrings, "__param");
exindex = find_sec(hdr, sechdrs, secstrings, "__ex_table");
obsparmindex = find_sec(hdr, sechdrs, secstrings, "__obsparm");
@@ -1935,7 +1997,7 @@ static struct module *load_module(void __user *umod,
layout_sections(mod, hdr, sechdrs, secstrings);
/* Do the allocs. */
- ptr = module_alloc(mod->core_size);
+ ptr = module_alloc_update_bounds(mod->core_size);
if (!ptr) {
err = -ENOMEM;
goto free_percpu;
@@ -1943,7 +2005,7 @@ static struct module *load_module(void __user *umod,
memset(ptr, 0, mod->core_size);
mod->module_core = ptr;
- ptr = module_alloc(mod->init_size);
+ ptr = module_alloc_update_bounds(mod->init_size);
if (!ptr && mod->init_size) {
err = -ENOMEM;
goto free_core;
@@ -2018,14 +2080,15 @@ static struct module *load_module(void __user *umod,
mod->gpl_crcs = (void *)sechdrs[gplcrcindex].sh_addr;
mod->num_gpl_future_syms = sechdrs[gplfutureindex].sh_size /
sizeof(*mod->gpl_future_syms);
- mod->num_unused_syms = sechdrs[unusedindex].sh_size /
- sizeof(*mod->unused_syms);
- mod->num_unused_gpl_syms = sechdrs[unusedgplindex].sh_size /
- sizeof(*mod->unused_gpl_syms);
mod->gpl_future_syms = (void *)sechdrs[gplfutureindex].sh_addr;
if (gplfuturecrcindex)
mod->gpl_future_crcs = (void *)sechdrs[gplfuturecrcindex].sh_addr;
+#ifdef CONFIG_UNUSED_SYMBOLS
+ mod->num_unused_syms = sechdrs[unusedindex].sh_size /
+ sizeof(*mod->unused_syms);
+ mod->num_unused_gpl_syms = sechdrs[unusedgplindex].sh_size /
+ sizeof(*mod->unused_gpl_syms);
mod->unused_syms = (void *)sechdrs[unusedindex].sh_addr;
if (unusedcrcindex)
mod->unused_crcs = (void *)sechdrs[unusedcrcindex].sh_addr;
@@ -2033,13 +2096,17 @@ static struct module *load_module(void __user *umod,
if (unusedgplcrcindex)
mod->unused_gpl_crcs
= (void *)sechdrs[unusedgplcrcindex].sh_addr;
+#endif
#ifdef CONFIG_MODVERSIONS
- if ((mod->num_syms && !crcindex) ||
- (mod->num_gpl_syms && !gplcrcindex) ||
- (mod->num_gpl_future_syms && !gplfuturecrcindex) ||
- (mod->num_unused_syms && !unusedcrcindex) ||
- (mod->num_unused_gpl_syms && !unusedgplcrcindex)) {
+ if ((mod->num_syms && !crcindex)
+ || (mod->num_gpl_syms && !gplcrcindex)
+ || (mod->num_gpl_future_syms && !gplfuturecrcindex)
+#ifdef CONFIG_UNUSED_SYMBOLS
+ || (mod->num_unused_syms && !unusedcrcindex)
+ || (mod->num_unused_gpl_syms && !unusedgplcrcindex)
+#endif
+ ) {
printk(KERN_WARNING "%s: No versions for exported symbols.\n", mod->name);
err = try_to_force_load(mod, "nocrc");
if (err)
@@ -2512,7 +2579,7 @@ static int m_show(struct seq_file *m, void *p)
struct module *mod = list_entry(p, struct module, list);
char buf[8];
- seq_printf(m, "%s %lu",
+ seq_printf(m, "%s %u",
mod->name, mod->init_size + mod->core_size);
print_unload_info(m, mod);
@@ -2595,6 +2662,9 @@ struct module *__module_text_address(unsigned long addr)
{
struct module *mod;
+ if (addr < module_addr_min || addr > module_addr_max)
+ return NULL;
+
list_for_each_entry(mod, &modules, list)
if (within(addr, mod->module_init, mod->init_text_size)
|| within(addr, mod->module_core, mod->core_text_size))
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