*/
#include <linux/export.h>
#include <linux/moduleloader.h>
-#include <linux/ftrace_event.h>
+#include <linux/trace_events.h>
#include <linux/init.h>
#include <linux/kallsyms.h>
#include <linux/file.h>
#include <linux/vermagic.h>
#include <linux/notifier.h>
#include <linux/sched.h>
-#include <linux/stop_machine.h>
#include <linux/device.h>
#include <linux/string.h>
#include <linux/mutex.h>
#include <linux/jump_label.h>
#include <linux/pfn.h>
#include <linux/bsearch.h>
-#include <linux/fips.h>
#include <uapi/linux/module.h>
#include "module-internal.h"
* 1) List of modules (also safely readable with preempt_disable),
* 2) module_use links,
* 3) module_addr_min/module_addr_max.
- * (delete uses stop_machine/add uses RCU list operations). */
+ * (delete and add uses RCU list operations). */
DEFINE_MUTEX(module_mutex);
EXPORT_SYMBOL_GPL(module_mutex);
static LIST_HEAD(modules);
-#ifdef CONFIG_KGDB_KDB
-struct list_head *kdb_modules = &modules; /* kdb needs the list of modules */
-#endif /* CONFIG_KGDB_KDB */
-#ifdef CONFIG_MODULE_SIG
-#ifdef CONFIG_MODULE_SIG_FORCE
-static bool sig_enforce = true;
-#else
-static bool sig_enforce = false;
+#ifdef CONFIG_MODULES_TREE_LOOKUP
+
+/*
+ * Use a latched RB-tree for __module_address(); this allows us to use
+ * RCU-sched lookups of the address from any context.
+ *
+ * Because modules have two address ranges: init and core, we need two
+ * latch_tree_nodes entries. Therefore we need the back-pointer from
+ * mod_tree_node.
+ *
+ * Because init ranges are short lived we mark them unlikely and have placed
+ * them outside the critical cacheline in struct module.
+ *
+ * This is conditional on PERF_EVENTS || TRACING because those can really hit
+ * __module_address() hard by doing a lot of stack unwinding; potentially from
+ * NMI context.
+ */
-static int param_set_bool_enable_only(const char *val,
- const struct kernel_param *kp)
+static __always_inline unsigned long __mod_tree_val(struct latch_tree_node *n)
{
- int err;
- bool test;
- struct kernel_param dummy_kp = *kp;
+ struct mod_tree_node *mtn = container_of(n, struct mod_tree_node, node);
+ struct module *mod = mtn->mod;
- dummy_kp.arg = &test;
+ if (unlikely(mtn == &mod->mtn_init))
+ return (unsigned long)mod->module_init;
- err = param_set_bool(val, &dummy_kp);
- if (err)
- return err;
+ return (unsigned long)mod->module_core;
+}
+
+static __always_inline unsigned long __mod_tree_size(struct latch_tree_node *n)
+{
+ struct mod_tree_node *mtn = container_of(n, struct mod_tree_node, node);
+ struct module *mod = mtn->mod;
+
+ if (unlikely(mtn == &mod->mtn_init))
+ return (unsigned long)mod->init_size;
+
+ return (unsigned long)mod->core_size;
+}
+
+static __always_inline bool
+mod_tree_less(struct latch_tree_node *a, struct latch_tree_node *b)
+{
+ return __mod_tree_val(a) < __mod_tree_val(b);
+}
+
+static __always_inline int
+mod_tree_comp(void *key, struct latch_tree_node *n)
+{
+ unsigned long val = (unsigned long)key;
+ unsigned long start, end;
- /* Don't let them unset it once it's set! */
- if (!test && sig_enforce)
- return -EROFS;
+ start = __mod_tree_val(n);
+ if (val < start)
+ return -1;
+
+ end = start + __mod_tree_size(n);
+ if (val >= end)
+ return 1;
- if (test)
- sig_enforce = true;
return 0;
}
-static const struct kernel_param_ops param_ops_bool_enable_only = {
- .set = param_set_bool_enable_only,
- .get = param_get_bool,
+static const struct latch_tree_ops mod_tree_ops = {
+ .less = mod_tree_less,
+ .comp = mod_tree_comp,
};
-#define param_check_bool_enable_only param_check_bool
+static struct mod_tree_root {
+ struct latch_tree_root root;
+ unsigned long addr_min;
+ unsigned long addr_max;
+} mod_tree __cacheline_aligned = {
+ .addr_min = -1UL,
+};
+
+#define module_addr_min mod_tree.addr_min
+#define module_addr_max mod_tree.addr_max
+
+static noinline void __mod_tree_insert(struct mod_tree_node *node)
+{
+ latch_tree_insert(&node->node, &mod_tree.root, &mod_tree_ops);
+}
+
+static void __mod_tree_remove(struct mod_tree_node *node)
+{
+ latch_tree_erase(&node->node, &mod_tree.root, &mod_tree_ops);
+}
+
+/*
+ * These modifications: insert, remove_init and remove; are serialized by the
+ * module_mutex.
+ */
+static void mod_tree_insert(struct module *mod)
+{
+ mod->mtn_core.mod = mod;
+ mod->mtn_init.mod = mod;
+
+ __mod_tree_insert(&mod->mtn_core);
+ if (mod->init_size)
+ __mod_tree_insert(&mod->mtn_init);
+}
+
+static void mod_tree_remove_init(struct module *mod)
+{
+ if (mod->init_size)
+ __mod_tree_remove(&mod->mtn_init);
+}
+
+static void mod_tree_remove(struct module *mod)
+{
+ __mod_tree_remove(&mod->mtn_core);
+ mod_tree_remove_init(mod);
+}
+
+static struct module *mod_find(unsigned long addr)
+{
+ struct latch_tree_node *ltn;
+
+ ltn = latch_tree_find((void *)addr, &mod_tree.root, &mod_tree_ops);
+ if (!ltn)
+ return NULL;
+
+ return container_of(ltn, struct mod_tree_node, node)->mod;
+}
+
+#else /* MODULES_TREE_LOOKUP */
+
+static unsigned long module_addr_min = -1UL, module_addr_max = 0;
+
+static void mod_tree_insert(struct module *mod) { }
+static void mod_tree_remove_init(struct module *mod) { }
+static void mod_tree_remove(struct module *mod) { }
+
+static struct module *mod_find(unsigned long addr)
+{
+ struct module *mod;
+
+ list_for_each_entry_rcu(mod, &modules, list) {
+ if (within_module(addr, mod))
+ return mod;
+ }
+
+ return NULL;
+}
+
+#endif /* MODULES_TREE_LOOKUP */
+
+/*
+ * Bounds of module text, for speeding up __module_address.
+ * Protected by module_mutex.
+ */
+static void __mod_update_bounds(void *base, unsigned int size)
+{
+ unsigned long min = (unsigned long)base;
+ unsigned long max = min + size;
+
+ if (min < module_addr_min)
+ module_addr_min = min;
+ if (max > module_addr_max)
+ module_addr_max = max;
+}
+
+static void mod_update_bounds(struct module *mod)
+{
+ __mod_update_bounds(mod->module_core, mod->core_size);
+ if (mod->init_size)
+ __mod_update_bounds(mod->module_init, mod->init_size);
+}
+
+#ifdef CONFIG_KGDB_KDB
+struct list_head *kdb_modules = &modules; /* kdb needs the list of modules */
+#endif /* CONFIG_KGDB_KDB */
+
+static void module_assert_mutex(void)
+{
+ lockdep_assert_held(&module_mutex);
+}
+
+static void module_assert_mutex_or_preempt(void)
+{
+#ifdef CONFIG_LOCKDEP
+ if (unlikely(!debug_locks))
+ return;
+
+ WARN_ON(!rcu_read_lock_sched_held() &&
+ !lockdep_is_held(&module_mutex));
+#endif
+}
+
+static bool sig_enforce = IS_ENABLED(CONFIG_MODULE_SIG_FORCE);
+#ifndef CONFIG_MODULE_SIG_FORCE
module_param(sig_enforce, bool_enable_only, 0644);
#endif /* !CONFIG_MODULE_SIG_FORCE */
-#endif /* CONFIG_MODULE_SIG */
/* Block module loading/unloading? */
int modules_disabled = 0;
static BLOCKING_NOTIFIER_HEAD(module_notify_list);
-/* Bounds of module allocation, for speeding __module_address.
- * Protected by module_mutex. */
-static unsigned long module_addr_min = -1UL, module_addr_max = 0;
-
-int register_module_notifier(struct notifier_block * nb)
+int register_module_notifier(struct notifier_block *nb)
{
return blocking_notifier_chain_register(&module_notify_list, nb);
}
EXPORT_SYMBOL(register_module_notifier);
-int unregister_module_notifier(struct notifier_block * nb)
+int unregister_module_notifier(struct notifier_block *nb)
{
return blocking_notifier_chain_unregister(&module_notify_list, nb);
}
struct _ddebug *debug;
unsigned int num_debug;
bool sig_ok;
+#ifdef CONFIG_KALLSYMS
+ unsigned long mod_kallsyms_init_off;
+#endif
struct {
unsigned int sym, str, mod, vers, info, pcpu;
} index;
#endif
};
+ module_assert_mutex_or_preempt();
+
if (each_symbol_in_section(arr, ARRAY_SIZE(arr), NULL, fn, data))
return true;
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);
+ pr_warn("Symbol %s is being used by a non-GPL module, "
+ "which will not be allowed in the future\n",
+ fsa->name);
}
}
#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");
+ pr_warn("Symbol %s is marked as UNUSED, however this module is "
+ "using it.\n", fsa->name);
+ pr_warn("This symbol will go away in the future.\n");
+ pr_warn("Please evaluate if this is the right api to use and "
+ "if it really is, submit a report to the linux kernel "
+ "mailing list together with submitting your code for "
+ "inclusion.\n");
}
#endif
}
EXPORT_SYMBOL_GPL(find_symbol);
-/* Search for module by name: must hold module_mutex. */
-static struct module *find_module_all(const char *name,
+/*
+ * Search for module by name: must hold module_mutex (or preempt disabled
+ * for read-only access).
+ */
+static struct module *find_module_all(const char *name, size_t len,
bool even_unformed)
{
struct module *mod;
+ module_assert_mutex_or_preempt();
+
list_for_each_entry(mod, &modules, list) {
if (!even_unformed && mod->state == MODULE_STATE_UNFORMED)
continue;
- if (strcmp(mod->name, name) == 0)
+ if (strlen(mod->name) == len && !memcmp(mod->name, name, len))
return mod;
}
return NULL;
struct module *find_module(const char *name)
{
- return find_module_all(name, false);
+ module_assert_mutex();
+ return find_module_all(name, strlen(name), false);
}
EXPORT_SYMBOL_GPL(find_module);
return mod->percpu;
}
-static int percpu_modalloc(struct module *mod,
- unsigned long size, unsigned long align)
+static int percpu_modalloc(struct module *mod, struct load_info *info)
{
+ Elf_Shdr *pcpusec = &info->sechdrs[info->index.pcpu];
+ unsigned long align = pcpusec->sh_addralign;
+
+ if (!pcpusec->sh_size)
+ return 0;
+
if (align > PAGE_SIZE) {
- printk(KERN_WARNING "%s: per-cpu alignment %li > %li\n",
- mod->name, align, PAGE_SIZE);
+ pr_warn("%s: per-cpu alignment %li > %li\n",
+ mod->name, align, PAGE_SIZE);
align = PAGE_SIZE;
}
- mod->percpu = __alloc_reserved_percpu(size, align);
+ mod->percpu = __alloc_reserved_percpu(pcpusec->sh_size, align);
if (!mod->percpu) {
- printk(KERN_WARNING
- "%s: Could not allocate %lu bytes percpu data\n",
- mod->name, size);
+ pr_warn("%s: Could not allocate %lu bytes percpu data\n",
+ mod->name, (unsigned long)pcpusec->sh_size);
return -ENOMEM;
}
- mod->percpu_size = size;
+ mod->percpu_size = pcpusec->sh_size;
return 0;
}
{
return NULL;
}
-static inline int percpu_modalloc(struct module *mod,
- unsigned long size, unsigned long align)
+static int percpu_modalloc(struct module *mod, struct load_info *info)
{
- return -ENOMEM;
+ /* UP modules shouldn't have this section: ENOMEM isn't quite right */
+ if (info->sechdrs[info->index.pcpu].sh_size != 0)
+ return -ENOMEM;
+ return 0;
}
static inline void percpu_modfree(struct module *mod)
{
static ssize_t show_modinfo_##field(struct module_attribute *mattr, \
struct module_kobject *mk, char *buffer) \
{ \
- return sprintf(buffer, "%s\n", mk->mod->field); \
+ return scnprintf(buffer, PAGE_SIZE, "%s\n", mk->mod->field); \
} \
static int modinfo_##field##_exists(struct module *mod) \
{ \
EXPORT_TRACEPOINT_SYMBOL(module_get);
+/* MODULE_REF_BASE is the base reference count by kmodule loader. */
+#define MODULE_REF_BASE 1
+
/* Init the unload section of the module. */
static int module_unload_init(struct module *mod)
{
- mod->refptr = alloc_percpu(struct module_ref);
- if (!mod->refptr)
- return -ENOMEM;
+ /*
+ * Initialize reference counter to MODULE_REF_BASE.
+ * refcnt == 0 means module is going.
+ */
+ atomic_set(&mod->refcnt, MODULE_REF_BASE);
INIT_LIST_HEAD(&mod->source_list);
INIT_LIST_HEAD(&mod->target_list);
/* Hold reference count during initialization. */
- __this_cpu_write(mod->refptr->incs, 1);
- /* Backwards compatibility macros put refcount during init. */
- mod->waiter = current;
+ atomic_inc(&mod->refcnt);
return 0;
}
pr_debug("Allocating new usage for %s.\n", a->name);
use = kmalloc(sizeof(*use), GFP_ATOMIC);
if (!use) {
- printk(KERN_WARNING "%s: out of memory loading\n", a->name);
+ pr_warn("%s: out of memory loading\n", a->name);
return -ENOMEM;
}
kfree(use);
}
mutex_unlock(&module_mutex);
-
- free_percpu(mod->refptr);
}
#ifdef CONFIG_MODULE_FORCE_UNLOAD
}
#endif /* CONFIG_MODULE_FORCE_UNLOAD */
-struct stopref
+/* Try to release refcount of module, 0 means success. */
+static int try_release_module_ref(struct module *mod)
{
- struct module *mod;
- int flags;
- int *forced;
-};
+ int ret;
-/* Whole machine is stopped with interrupts off when this runs. */
-static int __try_stop_module(void *_sref)
-{
- struct stopref *sref = _sref;
+ /* Try to decrement refcnt which we set at loading */
+ ret = atomic_sub_return(MODULE_REF_BASE, &mod->refcnt);
+ BUG_ON(ret < 0);
+ if (ret)
+ /* Someone can put this right now, recover with checking */
+ ret = atomic_add_unless(&mod->refcnt, MODULE_REF_BASE, 0);
+ return ret;
+}
+
+static int try_stop_module(struct module *mod, int flags, int *forced)
+{
/* If it's not unused, quit unless we're forcing. */
- if (module_refcount(sref->mod) != 0) {
- if (!(*sref->forced = try_force_unload(sref->flags)))
+ if (try_release_module_ref(mod) != 0) {
+ *forced = try_force_unload(flags);
+ if (!(*forced))
return -EWOULDBLOCK;
}
/* Mark it as dying. */
- sref->mod->state = MODULE_STATE_GOING;
+ mod->state = MODULE_STATE_GOING;
+
return 0;
}
-static int try_stop_module(struct module *mod, int flags, int *forced)
+/**
+ * module_refcount - return the refcount or -1 if unloading
+ *
+ * @mod: the module we're checking
+ *
+ * Returns:
+ * -1 if the module is in the process of unloading
+ * otherwise the number of references in the kernel to the module
+ */
+int module_refcount(struct module *mod)
{
- if (flags & O_NONBLOCK) {
- struct stopref sref = { mod, flags, forced };
-
- return stop_machine(__try_stop_module, &sref, NULL);
- } else {
- /* We don't need to stop the machine for this. */
- mod->state = MODULE_STATE_GOING;
- synchronize_sched();
- return 0;
- }
-}
-
-unsigned long module_refcount(struct module *mod)
-{
- unsigned long incs = 0, decs = 0;
- int cpu;
-
- for_each_possible_cpu(cpu)
- decs += per_cpu_ptr(mod->refptr, cpu)->decs;
- /*
- * ensure the incs are added up after the decs.
- * module_put ensures incs are visible before decs with smp_wmb.
- *
- * This 2-count scheme avoids the situation where the refcount
- * for CPU0 is read, then CPU0 increments the module refcount,
- * then CPU1 drops that refcount, then the refcount for CPU1 is
- * read. We would record a decrement but not its corresponding
- * increment so we would see a low count (disaster).
- *
- * Rare situation? But module_refcount can be preempted, and we
- * might be tallying up 4096+ CPUs. So it is not impossible.
- */
- smp_rmb();
- for_each_possible_cpu(cpu)
- incs += per_cpu_ptr(mod->refptr, cpu)->incs;
- return incs - decs;
+ return atomic_read(&mod->refcnt) - MODULE_REF_BASE;
}
EXPORT_SYMBOL(module_refcount);
/* This exists whether we can unload or not */
static void free_module(struct module *mod);
-static void wait_for_zero_refcount(struct module *mod)
-{
- /* Since we might sleep for some time, release the mutex first */
- mutex_unlock(&module_mutex);
- for (;;) {
- pr_debug("Looking at refcount...\n");
- set_current_state(TASK_UNINTERRUPTIBLE);
- if (module_refcount(mod) == 0)
- break;
- schedule();
- }
- current->state = TASK_RUNNING;
- mutex_lock(&module_mutex);
-}
-
SYSCALL_DEFINE2(delete_module, const char __user *, name_user,
unsigned int, flags)
{
/* Doing init or already dying? */
if (mod->state != MODULE_STATE_LIVE) {
- /* FIXME: if (force), slam module count and wake up
- waiter --RR */
+ /* FIXME: if (force), slam module count damn the torpedoes */
pr_debug("%s already dying\n", mod->name);
ret = -EBUSY;
goto out;
}
}
- /* Set this up before setting mod->state */
- mod->waiter = current;
-
/* Stop the machine so refcounts can't move and disable module. */
ret = try_stop_module(mod, flags, &forced);
if (ret != 0)
goto out;
- /* Never wait if forced. */
- if (!forced && module_refcount(mod) != 0)
- wait_for_zero_refcount(mod);
-
mutex_unlock(&module_mutex);
/* Final destruction now no one is using it. */
if (mod->exit != NULL)
struct module_use *use;
int printed_something = 0;
- seq_printf(m, " %lu ", module_refcount(mod));
+ seq_printf(m, " %i ", module_refcount(mod));
- /* Always include a trailing , so userspace can differentiate
- between this and the old multi-field proc format. */
+ /*
+ * Always include a trailing , so userspace can differentiate
+ * between this and the old multi-field proc format.
+ */
list_for_each_entry(use, &mod->source_list, source_list) {
printed_something = 1;
seq_printf(m, "%s,", use->source->name);
if (mod->init != NULL && mod->exit == NULL) {
printed_something = 1;
- seq_printf(m, "[permanent],");
+ seq_puts(m, "[permanent],");
}
if (!printed_something)
- seq_printf(m, "-");
+ seq_puts(m, "-");
}
void __symbol_put(const char *symbol)
if (core_kernel_text(a))
return;
- /* module_text_address is safe here: we're supposed to have reference
- * to module from symbol_get, so it can't go away. */
+ /*
+ * Even though we hold a reference on the module; we still need to
+ * disable preemption in order to safely traverse the data structure.
+ */
+ preempt_disable();
modaddr = __module_text_address(a);
BUG_ON(!modaddr);
module_put(modaddr);
+ preempt_enable();
}
EXPORT_SYMBOL_GPL(symbol_put_addr);
static ssize_t show_refcnt(struct module_attribute *mattr,
struct module_kobject *mk, char *buffer)
{
- return sprintf(buffer, "%lu\n", module_refcount(mk->mod));
+ return sprintf(buffer, "%i\n", module_refcount(mk->mod));
}
static struct module_attribute modinfo_refcnt =
{
if (module) {
preempt_disable();
- __this_cpu_inc(module->refptr->incs);
+ atomic_inc(&module->refcnt);
trace_module_get(module, _RET_IP_);
preempt_enable();
}
if (module) {
preempt_disable();
-
- if (likely(module_is_live(module))) {
- __this_cpu_inc(module->refptr->incs);
+ /* Note: here, we can fail to get a reference */
+ if (likely(module_is_live(module) &&
+ atomic_inc_not_zero(&module->refcnt) != 0))
trace_module_get(module, _RET_IP_);
- } else
+ else
ret = false;
preempt_enable();
void module_put(struct module *module)
{
+ int ret;
+
if (module) {
preempt_disable();
- smp_wmb(); /* see comment in module_refcount */
- __this_cpu_inc(module->refptr->decs);
-
+ ret = atomic_dec_if_positive(&module->refcnt);
+ WARN_ON(ret < 0); /* Failed to put refcount */
trace_module_put(module, _RET_IP_);
- /* Maybe they're waiting for us to drop reference? */
- if (unlikely(!module_is_live(module)))
- wake_up_process(module->waiter);
preempt_enable();
}
}
static inline void print_unload_info(struct seq_file *m, struct module *mod)
{
/* We don't know the usage count, or what modules are using. */
- seq_printf(m, " - -");
+ seq_puts(m, " - -");
}
static inline void module_unload_free(struct module *mod)
buf[l++] = 'F';
if (mod->taints & (1 << TAINT_CRAP))
buf[l++] = 'C';
+ if (mod->taints & (1 << TAINT_UNSIGNED_MODULE))
+ buf[l++] = 'E';
/*
* TAINT_FORCED_RMMOD: could be added.
- * TAINT_UNSAFE_SMP, TAINT_MACHINE_CHECK, TAINT_BAD_PAGE don't
+ * TAINT_CPU_OUT_OF_SPEC, TAINT_MACHINE_CHECK, TAINT_BAD_PAGE don't
* apply to modules.
*/
return l;
{
#ifdef CONFIG_MODULE_FORCE_LOAD
if (!test_taint(TAINT_FORCED_MODULE))
- printk(KERN_WARNING "%s: %s: kernel tainted.\n",
- mod->name, reason);
+ pr_warn("%s: %s: kernel tainted.\n", mod->name, reason);
add_taint_module(mod, TAINT_FORCED_MODULE, LOCKDEP_NOW_UNRELIABLE);
return 0;
#else
static int check_version(Elf_Shdr *sechdrs,
unsigned int versindex,
const char *symname,
- struct module *mod,
+ struct module *mod,
const unsigned long *crc,
const struct module *crc_owner)
{
goto bad_version;
}
- printk(KERN_WARNING "%s: no symbol version for %s\n",
- mod->name, symname);
+ pr_warn("%s: no symbol version for %s\n", mod->name, symname);
return 0;
bad_version:
- printk("%s: disagrees about version of symbol %s\n",
+ pr_warn("%s: disagrees about version of symbol %s\n",
mod->name, symname);
return 0;
}
{
const unsigned long *crc;
- /* Since this should be found in kernel (which can't be removed),
- * no locking is necessary. */
+ /*
+ * Since this should be found in kernel (which can't be removed), no
+ * locking is necessary -- use preempt_disable() to placate lockdep.
+ */
+ preempt_disable();
if (!find_symbol(VMLINUX_SYMBOL_STR(module_layout), NULL,
- &crc, true, false))
+ &crc, true, false)) {
+ preempt_enable();
BUG();
+ }
+ preempt_enable();
return check_version(sechdrs, versindex,
VMLINUX_SYMBOL_STR(module_layout), mod, crc,
NULL);
static inline int check_version(Elf_Shdr *sechdrs,
unsigned int versindex,
const char *symname,
- struct module *mod,
+ struct module *mod,
const unsigned long *crc,
const struct module *crc_owner)
{
const unsigned long *crc;
int err;
+ /*
+ * The module_mutex should not be a heavily contended lock;
+ * if we get the occasional sleep here, we'll go an extra iteration
+ * in the wait_event_interruptible(), which is harmless.
+ */
+ sched_annotate_sleep();
mutex_lock(&module_mutex);
sym = find_symbol(name, &owner, &crc,
!(mod->taints & (1 << TAINT_PROPRIETARY_MODULE)), true);
!IS_ERR(ksym = resolve_symbol(mod, info, name, owner))
|| PTR_ERR(ksym) != -EBUSY,
30 * HZ) <= 0) {
- printk(KERN_WARNING "%s: gave up waiting for init of module %s.\n",
- mod->name, owner);
+ pr_warn("%s: gave up waiting for init of module %s.\n",
+ mod->name, owner);
}
return ksym;
}
return !(sect->sh_flags & SHF_ALLOC) || sect->sh_size == 0;
}
-struct module_sect_attr
-{
+struct module_sect_attr {
struct module_attribute mattr;
char *name;
unsigned long address;
};
-struct module_sect_attrs
-{
+struct module_sect_attrs {
struct attribute_group grp;
unsigned int nsections;
struct module_sect_attr attrs[0];
(attr->test && attr->test(mod))) {
memcpy(temp_attr, attr, sizeof(*temp_attr));
sysfs_attr_init(&temp_attr->attr);
- error = sysfs_create_file(&mod->mkobj.kobj,&temp_attr->attr);
+ error = sysfs_create_file(&mod->mkobj.kobj,
+ &temp_attr->attr);
++temp_attr;
}
}
/* pick a field to test for end of list */
if (!attr->attr.name)
break;
- sysfs_remove_file(&mod->mkobj.kobj,&attr->attr);
+ sysfs_remove_file(&mod->mkobj.kobj, &attr->attr);
if (attr->free)
attr->free(mod);
}
kfree(mod->modinfo_attrs);
}
+static void mod_kobject_put(struct module *mod)
+{
+ DECLARE_COMPLETION_ONSTACK(c);
+ mod->mkobj.kobj_completion = &c;
+ kobject_put(&mod->mkobj.kobj);
+ wait_for_completion(&c);
+}
+
static int mod_sysfs_init(struct module *mod)
{
int err;
struct kobject *kobj;
if (!module_sysfs_initialized) {
- printk(KERN_ERR "%s: module sysfs not initialized\n",
- mod->name);
+ pr_err("%s: module sysfs not initialized\n", mod->name);
err = -EINVAL;
goto out;
}
kobj = kset_find_obj(module_kset, mod->name);
if (kobj) {
- printk(KERN_ERR "%s: module is already loaded\n", mod->name);
+ pr_err("%s: module is already loaded\n", mod->name);
kobject_put(kobj);
err = -EINVAL;
goto out;
err = kobject_init_and_add(&mod->mkobj.kobj, &module_ktype, NULL,
"%s", mod->name);
if (err)
- kobject_put(&mod->mkobj.kobj);
+ mod_kobject_put(mod);
/* delay uevent until full sysfs population */
out:
out_unreg_holders:
kobject_put(mod->holders_dir);
out_unreg:
- kobject_put(&mod->mkobj.kobj);
+ mod_kobject_put(mod);
out:
return err;
}
{
remove_notes_attrs(mod);
remove_sect_attrs(mod);
- kobject_put(&mod->mkobj.kobj);
+ mod_kobject_put(mod);
}
+static void init_param_lock(struct module *mod)
+{
+ mutex_init(&mod->param_lock);
+}
#else /* !CONFIG_SYSFS */
static int mod_sysfs_setup(struct module *mod,
{
}
+static void init_param_lock(struct module *mod)
+{
+}
#endif /* CONFIG_SYSFS */
static void mod_sysfs_teardown(struct module *mod)
mod_sysfs_fini(mod);
}
-/*
- * unlink the module with the whole machine is stopped with interrupts off
- * - this defends against kallsyms not taking locks
- */
-static int __unlink_module(void *_mod)
-{
- struct module *mod = _mod;
- list_del(&mod->list);
- module_bug_cleanup(mod);
- return 0;
-}
-
#ifdef CONFIG_DEBUG_SET_MODULE_RONX
/*
* LKM RO/NX protection: protect module's text/ro-data
static void unset_module_init_ro_nx(struct module *mod) { }
#endif
-void __weak module_free(struct module *mod, void *module_region)
+void __weak module_memfree(void *module_region)
{
vfree(module_region);
}
{
}
+void __weak module_arch_freeing_init(struct module *mod)
+{
+}
+
/* Free a module, remove from lists, etc. */
static void free_module(struct module *mod)
{
/* We leave it in list to prevent duplicate loads, but make sure
* that noone uses it while it's being deconstructed. */
+ mutex_lock(&module_mutex);
mod->state = MODULE_STATE_UNFORMED;
+ mutex_unlock(&module_mutex);
/* Remove dynamic debug info */
ddebug_remove_module(mod->name);
/* Now we can delete it from the lists */
mutex_lock(&module_mutex);
- stop_machine(__unlink_module, mod, NULL);
+ /* Unlink carefully: kallsyms could be walking list. */
+ list_del_rcu(&mod->list);
+ mod_tree_remove(mod);
+ /* Remove this module from bug list, this uses list_del_rcu */
+ module_bug_cleanup(mod);
+ /* Wait for RCU-sched synchronizing before releasing mod->list and buglist. */
+ synchronize_sched();
mutex_unlock(&module_mutex);
/* This may be NULL, but that's OK */
unset_module_init_ro_nx(mod);
- module_free(mod, mod->module_init);
+ module_arch_freeing_init(mod);
+ module_memfree(mod->module_init);
kfree(mod->args);
percpu_modfree(mod);
- /* Free lock-classes: */
+ /* Free lock-classes; relies on the preceding sync_rcu(). */
lockdep_free_key_range(mod->module_core, mod->core_size);
/* Finally, free the core (containing the module structure) */
unset_module_core_ro_nx(mod);
- module_free(mod, mod->module_core);
+ module_memfree(mod->module_core);
#ifdef CONFIG_MPU
update_protections(current->mm);
for (i = 0; i < ARRAY_SIZE(arr); i++) {
for (s = arr[i].sym; s < arr[i].sym + arr[i].num; s++) {
if (find_symbol(s->name, &owner, NULL, true, false)) {
- printk(KERN_ERR
- "%s: exports duplicate symbol %s"
+ pr_err("%s: exports duplicate symbol %s"
" (owned by %s)\n",
mod->name, s->name, module_name(owner));
return -ENOEXEC;
switch (sym[i].st_shndx) {
case SHN_COMMON:
+ /* Ignore common symbols */
+ if (!strncmp(name, "__gnu_lto", 9))
+ break;
+
/* We compiled with -fno-common. These are not
supposed to happen. */
pr_debug("Common symbol: %s\n", name);
- printk("%s: please compile with -fno-common\n",
+ pr_warn("%s: please compile with -fno-common\n",
mod->name);
ret = -ENOEXEC;
break;
if (!ksym && ELF_ST_BIND(sym[i].st_info) == STB_WEAK)
break;
- printk(KERN_WARNING "%s: Unknown symbol %s (err %li)\n",
- mod->name, name, PTR_ERR(ksym));
+ pr_warn("%s: Unknown symbol %s (err %li)\n",
+ mod->name, name, PTR_ERR(ksym));
ret = PTR_ERR(ksym) ?: -ENOENT;
break;
if (!license_is_gpl_compatible(license)) {
if (!test_taint(TAINT_PROPRIETARY_MODULE))
- printk(KERN_WARNING "%s: module license '%s' taints "
- "kernel.\n", mod->name, license);
+ pr_warn("%s: module license '%s' taints kernel.\n",
+ mod->name, license);
add_taint_module(mod, TAINT_PROPRIETARY_MODULE,
LOCKDEP_NOW_UNRELIABLE);
}
}
static bool is_core_symbol(const Elf_Sym *src, const Elf_Shdr *sechdrs,
- unsigned int shnum)
+ unsigned int shnum)
{
const Elf_Shdr *sec;
info->symoffs = ALIGN(mod->core_size, symsect->sh_addralign ?: 1);
info->stroffs = mod->core_size = info->symoffs + ndst * sizeof(Elf_Sym);
mod->core_size += strtab_size;
+ mod->core_size = debug_align(mod->core_size);
/* 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,
info->index.str) | INIT_OFFSET_MASK;
pr_debug("\t%s\n", info->secstrings + strsect->sh_name);
+
+ /* We'll tack temporary mod_kallsyms on the end. */
+ mod->init_size = ALIGN(mod->init_size,
+ __alignof__(struct mod_kallsyms));
+ info->mod_kallsyms_init_off = mod->init_size;
+ mod->init_size += sizeof(struct mod_kallsyms);
+ mod->init_size = debug_align(mod->init_size);
}
+/*
+ * We use the full symtab and strtab which layout_symtab arranged to
+ * be appended to the init section. Later we switch to the cut-down
+ * core-only ones.
+ */
static void add_kallsyms(struct module *mod, const struct load_info *info)
{
unsigned int i, ndst;
char *s;
Elf_Shdr *symsec = &info->sechdrs[info->index.sym];
- mod->symtab = (void *)symsec->sh_addr;
- mod->num_symtab = symsec->sh_size / sizeof(Elf_Sym);
+ /* Set up to point into init section. */
+ mod->kallsyms = mod->module_init + info->mod_kallsyms_init_off;
+
+ mod->kallsyms->symtab = (void *)symsec->sh_addr;
+ mod->kallsyms->num_symtab = symsec->sh_size / sizeof(Elf_Sym);
/* Make sure we get permanent strtab: don't use info->strtab. */
- mod->strtab = (void *)info->sechdrs[info->index.str].sh_addr;
+ mod->kallsyms->strtab = (void *)info->sechdrs[info->index.str].sh_addr;
/* Set types up while we still have access to sections. */
- for (i = 0; i < mod->num_symtab; i++)
- mod->symtab[i].st_info = elf_type(&mod->symtab[i], info);
-
- mod->core_symtab = dst = mod->module_core + info->symoffs;
- mod->core_strtab = s = mod->module_core + info->stroffs;
- src = mod->symtab;
- for (ndst = i = 0; i < mod->num_symtab; i++) {
+ for (i = 0; i < mod->kallsyms->num_symtab; i++)
+ mod->kallsyms->symtab[i].st_info
+ = elf_type(&mod->kallsyms->symtab[i], info);
+
+ /* Now populate the cut down core kallsyms for after init. */
+ mod->core_kallsyms.symtab = dst = mod->module_core + info->symoffs;
+ mod->core_kallsyms.strtab = s = mod->module_core + info->stroffs;
+ src = mod->kallsyms->symtab;
+ for (ndst = i = 0; i < mod->kallsyms->num_symtab; i++) {
if (i == 0 ||
is_core_symbol(src+i, info->sechdrs, info->hdr->e_shnum)) {
dst[ndst] = src[i];
- dst[ndst++].st_name = s - mod->core_strtab;
- s += strlcpy(s, &mod->strtab[src[i].st_name],
+ dst[ndst++].st_name = s - mod->core_kallsyms.strtab;
+ s += strlcpy(s, &mod->kallsyms->strtab[src[i].st_name],
KSYM_NAME_LEN) + 1;
}
}
- mod->core_num_syms = ndst;
+ mod->core_kallsyms.num_symtab = ndst;
}
#else
static inline void layout_symtab(struct module *mod, struct load_info *info)
return;
#ifdef CONFIG_DYNAMIC_DEBUG
if (ddebug_add_module(debug, num, debug->modname))
- printk(KERN_ERR "dynamic debug error adding module: %s\n",
- debug->modname);
+ pr_err("dynamic debug error adding module: %s\n",
+ debug->modname);
#endif
}
return vmalloc_exec(size);
}
-static void *module_alloc_update_bounds(unsigned long size)
-{
- void *ret = module_alloc(size);
-
- if (ret) {
- mutex_lock(&module_mutex);
- /* 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;
- mutex_unlock(&module_mutex);
- }
- return ret;
-}
-
#ifdef CONFIG_DEBUG_KMEMLEAK
static void kmemleak_load_module(const struct module *mod,
const struct load_info *info)
#endif
#ifdef CONFIG_MODULE_SIG
-static int module_sig_check(struct load_info *info)
+static int module_sig_check(struct load_info *info, int flags)
{
int err = -ENOKEY;
const unsigned long markerlen = sizeof(MODULE_SIG_STRING) - 1;
const void *mod = info->hdr;
- if (info->len > markerlen &&
+ /*
+ * Require flags == 0, as a module with version information
+ * removed is no longer the module that was signed
+ */
+ if (flags == 0 &&
+ info->len > markerlen &&
memcmp(mod + info->len - markerlen, MODULE_SIG_STRING, markerlen) == 0) {
/* We truncate the module to discard the signature */
info->len -= markerlen;
}
/* Not having a signature is only an error if we're strict. */
- if (err < 0 && fips_enabled)
- panic("Module verification failed with error %d in FIPS mode\n",
- err);
if (err == -ENOKEY && !sig_enforce)
err = 0;
return err;
}
#else /* !CONFIG_MODULE_SIG */
-static int module_sig_check(struct load_info *info)
+static int module_sig_check(struct load_info *info, int flags)
{
return 0;
}
return 0;
}
+#define COPY_CHUNK_SIZE (16*PAGE_SIZE)
+
+static int copy_chunked_from_user(void *dst, const void __user *usrc, unsigned long len)
+{
+ do {
+ unsigned long n = min(len, COPY_CHUNK_SIZE);
+
+ if (copy_from_user(dst, usrc, n) != 0)
+ return -EFAULT;
+ cond_resched();
+ dst += n;
+ usrc += n;
+ len -= n;
+ } while (len);
+ return 0;
+}
+
/* Sets info->hdr and info->len. */
static int copy_module_from_user(const void __user *umod, unsigned long len,
struct load_info *info)
return err;
/* Suck in entire file: we'll want most of it. */
- info->hdr = vmalloc(info->len);
+ info->hdr = __vmalloc(info->len,
+ GFP_KERNEL | __GFP_HIGHMEM | __GFP_NOWARN, PAGE_KERNEL);
if (!info->hdr)
return -ENOMEM;
- if (copy_from_user(info->hdr, umod, info->len) != 0) {
+ if (copy_chunked_from_user(info->hdr, umod, info->len) != 0) {
vfree(info->hdr);
return -EFAULT;
}
/* Sets info->hdr and info->len. */
static int copy_module_from_fd(int fd, struct load_info *info)
{
- struct file *file;
+ struct fd f = fdget(fd);
int err;
struct kstat stat;
loff_t pos;
ssize_t bytes = 0;
- file = fget(fd);
- if (!file)
+ if (!f.file)
return -ENOEXEC;
- err = security_kernel_module_from_file(file);
+ err = security_kernel_module_from_file(f.file);
if (err)
goto out;
- err = vfs_getattr(&file->f_path, &stat);
+ err = vfs_getattr(&f.file->f_path, &stat);
if (err)
goto out;
pos = 0;
while (pos < stat.size) {
- bytes = kernel_read(file, pos, (char *)(info->hdr) + pos,
+ bytes = kernel_read(f.file, pos, (char *)(info->hdr) + pos,
stat.size - pos);
if (bytes < 0) {
vfree(info->hdr);
info->len = pos;
out:
- fput(file);
+ fdput(f);
return err;
}
Elf_Shdr *shdr = &info->sechdrs[i];
if (shdr->sh_type != SHT_NOBITS
&& info->len < shdr->sh_offset + shdr->sh_size) {
- printk(KERN_ERR "Module len %lu truncated\n",
- info->len);
+ pr_err("Module len %lu truncated\n", info->len);
return -ENOEXEC;
}
info->index.mod = find_sec(info, ".gnu.linkonce.this_module");
if (!info->index.mod) {
- printk(KERN_WARNING "No module found in object\n");
+ pr_warn("No module found in object\n");
return ERR_PTR(-ENOEXEC);
}
/* This is temporary: point mod into copy of data. */
mod = (void *)info->sechdrs[info->index.mod].sh_addr;
if (info->index.sym == 0) {
- printk(KERN_WARNING "%s: module has no symbols (stripped?)\n",
- mod->name);
+ pr_warn("%s: module has no symbols (stripped?)\n", mod->name);
return ERR_PTR(-ENOEXEC);
}
if (err)
return err;
} else if (!same_magic(modmagic, vermagic, info->index.vers)) {
- printk(KERN_ERR "%s: version magic '%s' should be '%s'\n",
+ pr_err("%s: version magic '%s' should be '%s'\n",
mod->name, modmagic, vermagic);
return -ENOEXEC;
}
if (get_modinfo(info, "staging")) {
add_taint_module(mod, TAINT_CRAP, LOCKDEP_STILL_OK);
- printk(KERN_WARNING "%s: module is from the staging directory,"
- " the quality is unknown, you have been warned.\n",
- mod->name);
+ pr_warn("%s: module is from the staging directory, the quality "
+ "is unknown, you have been warned.\n", mod->name);
}
/* Set up license info based on the info section */
return 0;
}
-static void find_module_sections(struct module *mod, struct load_info *info)
+static int find_module_sections(struct module *mod, struct load_info *info)
{
mod->kp = section_objs(info, "__param",
sizeof(*mod->kp), &mod->num_kp);
#ifdef CONFIG_CONSTRUCTORS
mod->ctors = section_objs(info, ".ctors",
sizeof(*mod->ctors), &mod->num_ctors);
+ if (!mod->ctors)
+ mod->ctors = section_objs(info, ".init_array",
+ sizeof(*mod->ctors), &mod->num_ctors);
+ else if (find_sec(info, ".init_array")) {
+ /*
+ * This shouldn't happen with same compiler and binutils
+ * building all parts of the module.
+ */
+ pr_warn("%s: has both .ctors and .init_array.\n",
+ mod->name);
+ return -EINVAL;
+ }
#endif
#ifdef CONFIG_TRACEPOINTS
mod->trace_events = section_objs(info, "_ftrace_events",
sizeof(*mod->trace_events),
&mod->num_trace_events);
+ mod->trace_enums = section_objs(info, "_ftrace_enum_map",
+ sizeof(*mod->trace_enums),
+ &mod->num_trace_enums);
#endif
#ifdef CONFIG_TRACING
mod->trace_bprintk_fmt_start = section_objs(info, "__trace_printk_fmt",
sizeof(*mod->extable), &mod->num_exentries);
if (section_addr(info, "__obsparm"))
- printk(KERN_WARNING "%s: Ignoring obsolete parameters\n",
- mod->name);
+ pr_warn("%s: Ignoring obsolete parameters\n", mod->name);
info->debug = section_objs(info, "__verbose",
sizeof(*info->debug), &info->num_debug);
+
+ return 0;
}
static int move_module(struct module *mod, struct load_info *info)
void *ptr;
/* Do the allocs. */
- ptr = module_alloc_update_bounds(mod->core_size);
+ ptr = module_alloc(mod->core_size);
/*
* The pointer to this block is stored in the module structure
* which is inside the block. Just mark it as not being a
mod->module_core = ptr;
if (mod->init_size) {
- ptr = module_alloc_update_bounds(mod->init_size);
+ ptr = module_alloc(mod->init_size);
/*
* The pointer to this block is stored in the module structure
* which is inside the block. This block doesn't need to be
*/
kmemleak_ignore(ptr);
if (!ptr) {
- module_free(mod, mod->module_core);
+ module_memfree(mod->module_core);
return -ENOMEM;
}
memset(ptr, 0, mod->init_size);
{
/* Module within temporary copy. */
struct module *mod;
- Elf_Shdr *pcpusec;
int err;
mod = setup_load_info(info, flags);
err = module_frob_arch_sections(info->hdr, info->sechdrs,
info->secstrings, mod);
if (err < 0)
- goto out;
+ return ERR_PTR(err);
- pcpusec = &info->sechdrs[info->index.pcpu];
- if (pcpusec->sh_size) {
- /* We have a special allocation for this section. */
- err = percpu_modalloc(mod,
- pcpusec->sh_size, pcpusec->sh_addralign);
- if (err)
- goto out;
- pcpusec->sh_flags &= ~(unsigned long)SHF_ALLOC;
- }
+ /* We will do a special allocation for per-cpu sections later. */
+ info->sechdrs[info->index.pcpu].sh_flags &= ~(unsigned long)SHF_ALLOC;
/* Determine total sizes, and put offsets in sh_entsize. For now
this is done generically; there doesn't appear to be any
/* Allocate and move to the final place */
err = move_module(mod, info);
if (err)
- goto free_percpu;
+ return ERR_PTR(err);
/* Module has been copied to its final place now: return it. */
mod = (void *)info->sechdrs[info->index.mod].sh_addr;
kmemleak_load_module(mod, info);
return mod;
-
-free_percpu:
- percpu_modfree(mod);
-out:
- return ERR_PTR(err);
}
/* mod is no longer valid after this! */
static void module_deallocate(struct module *mod, struct load_info *info)
{
percpu_modfree(mod);
- module_free(mod, mod->module_init);
- module_free(mod, mod->module_core);
+ module_arch_freeing_init(mod);
+ module_memfree(mod->module_init);
+ module_memfree(mod->module_core);
}
int __weak module_finalize(const Elf_Ehdr *hdr,
struct module *mod;
bool ret;
+ /*
+ * The module_mutex should not be a heavily contended lock;
+ * if we get the occasional sleep here, we'll go an extra iteration
+ * in the wait_event_interruptible(), which is harmless.
+ */
+ sched_annotate_sleep();
mutex_lock(&module_mutex);
- mod = find_module_all(name, true);
+ mod = find_module_all(name, strlen(name), true);
ret = !mod || mod->state == MODULE_STATE_LIVE
|| mod->state == MODULE_STATE_GOING;
mutex_unlock(&module_mutex);
#endif
}
-/* This is where the real work happens */
-static int do_init_module(struct module *mod)
+/* For freeing module_init on success, in case kallsyms traversing */
+struct mod_initfree {
+ struct rcu_head rcu;
+ void *module_init;
+};
+
+static void do_free_init(struct rcu_head *head)
+{
+ struct mod_initfree *m = container_of(head, struct mod_initfree, rcu);
+ module_memfree(m->module_init);
+ kfree(m);
+}
+
+/*
+ * This is where the real work happens.
+ *
+ * Keep it uninlined to provide a reliable breakpoint target, e.g. for the gdb
+ * helper command 'lx-symbols'.
+ */
+static noinline int do_init_module(struct module *mod)
{
int ret = 0;
+ struct mod_initfree *freeinit;
+
+ freeinit = kmalloc(sizeof(*freeinit), GFP_KERNEL);
+ if (!freeinit) {
+ ret = -ENOMEM;
+ goto fail;
+ }
+ freeinit->module_init = mod->module_init;
/*
* We want to find out whether @mod uses async during init. Clear
*/
current->flags &= ~PF_USED_ASYNC;
- blocking_notifier_call_chain(&module_notify_list,
- MODULE_STATE_COMING, mod);
-
- /* Set RO and NX regions for core */
- set_section_ro_nx(mod->module_core,
- mod->core_text_size,
- mod->core_ro_size,
- mod->core_size);
-
- /* Set RO and NX regions for init */
- set_section_ro_nx(mod->module_init,
- mod->init_text_size,
- mod->init_ro_size,
- mod->init_size);
-
do_mod_ctors(mod);
/* Start the module */
if (mod->init != NULL)
ret = do_one_initcall(mod->init);
if (ret < 0) {
- /* Init routine failed: abort. Try to protect us from
- buggy refcounters. */
- mod->state = MODULE_STATE_GOING;
- synchronize_sched();
- module_put(mod);
- blocking_notifier_call_chain(&module_notify_list,
- MODULE_STATE_GOING, mod);
- free_module(mod);
- wake_up_all(&module_wq);
- return ret;
+ goto fail_free_freeinit;
}
if (ret > 0) {
- printk(KERN_WARNING
-"%s: '%s'->init suspiciously returned %d, it should follow 0/-E convention\n"
-"%s: loading module anyway...\n",
- __func__, mod->name, ret,
- __func__);
+ pr_warn("%s: '%s'->init suspiciously returned %d, it should "
+ "follow 0/-E convention\n"
+ "%s: loading module anyway...\n",
+ __func__, mod->name, ret, __func__);
dump_stack();
}
*
* http://thread.gmane.org/gmane.linux.kernel/1420814
*/
- if (current->flags & PF_USED_ASYNC)
+ if (!mod->async_probe_requested && (current->flags & PF_USED_ASYNC))
async_synchronize_full();
mutex_lock(&module_mutex);
module_put(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;
+ /* Switch to core kallsyms now init is done: kallsyms may be walking! */
+ rcu_assign_pointer(mod->kallsyms, &mod->core_kallsyms);
#endif
+ mod_tree_remove_init(mod);
unset_module_init_ro_nx(mod);
- module_free(mod, mod->module_init);
+ module_arch_freeing_init(mod);
mod->module_init = NULL;
mod->init_size = 0;
mod->init_ro_size = 0;
mod->init_text_size = 0;
+ /*
+ * We want to free module_init, but be aware that kallsyms may be
+ * walking this with preempt disabled. In all the failure paths, we
+ * call synchronize_sched(), but we don't want to slow down the success
+ * path, so use actual RCU here.
+ */
+ call_rcu_sched(&freeinit->rcu, do_free_init);
mutex_unlock(&module_mutex);
wake_up_all(&module_wq);
return 0;
+
+fail_free_freeinit:
+ kfree(freeinit);
+fail:
+ /* Try to protect us from buggy refcounters. */
+ mod->state = MODULE_STATE_GOING;
+ synchronize_sched();
+ module_put(mod);
+ blocking_notifier_call_chain(&module_notify_list,
+ MODULE_STATE_GOING, mod);
+ free_module(mod);
+ wake_up_all(&module_wq);
+ return ret;
}
static int may_init_module(void)
again:
mutex_lock(&module_mutex);
- if ((old = find_module_all(mod->name, true)) != NULL) {
+ old = find_module_all(mod->name, strlen(mod->name), true);
+ if (old != NULL) {
if (old->state == MODULE_STATE_COMING
|| old->state == MODULE_STATE_UNFORMED) {
/* Wait in case it fails to load. */
err = -EEXIST;
goto out;
}
+ mod_update_bounds(mod);
list_add_rcu(&mod->list, &modules);
+ mod_tree_insert(mod);
err = 0;
out:
/* This relies on module_mutex for list integrity. */
module_bug_finalize(info->hdr, info->sechdrs, mod);
+ /* Set RO and NX regions for core */
+ set_section_ro_nx(mod->module_core,
+ mod->core_text_size,
+ mod->core_ro_size,
+ mod->core_size);
+
+ /* Set RO and NX regions for init */
+ set_section_ro_nx(mod->module_init,
+ mod->init_text_size,
+ mod->init_ro_size,
+ mod->init_size);
+
/* Mark state as coming so strong_try_module_get() ignores us,
* but kallsyms etc. can see us. */
mod->state = MODULE_STATE_COMING;
+ mutex_unlock(&module_mutex);
+
+ blocking_notifier_call_chain(&module_notify_list,
+ MODULE_STATE_COMING, mod);
+ return 0;
out:
mutex_unlock(&module_mutex);
return err;
}
+static int unknown_module_param_cb(char *param, char *val, const char *modname,
+ void *arg)
+{
+ struct module *mod = arg;
+ int ret;
+
+ if (strcmp(param, "async_probe") == 0) {
+ mod->async_probe_requested = true;
+ return 0;
+ }
+
+ /* Check for magic 'dyndbg' arg */
+ ret = ddebug_dyndbg_module_param_cb(param, val, modname);
+ if (ret != 0)
+ pr_warn("%s: unknown parameter '%s' ignored\n", modname, param);
+ return 0;
+}
+
/* Allocate and load the module: note that size of section 0 is always
zero, and we rely on this for optional sections. */
static int load_module(struct load_info *info, const char __user *uargs,
{
struct module *mod;
long err;
+ char *after_dashes;
- err = module_sig_check(info);
+ err = module_sig_check(info, flags);
if (err)
goto free_copy;
#ifdef CONFIG_MODULE_SIG
mod->sig_ok = info->sig_ok;
if (!mod->sig_ok) {
- printk_once(KERN_NOTICE
- "%s: module verification failed: signature and/or"
- " required key missing - tainting kernel\n",
- mod->name);
- add_taint_module(mod, TAINT_FORCED_MODULE, LOCKDEP_STILL_OK);
+ pr_notice_once("%s: module verification failed: signature "
+ "and/or required key missing - tainting "
+ "kernel\n", mod->name);
+ add_taint_module(mod, TAINT_UNSIGNED_MODULE, LOCKDEP_STILL_OK);
}
#endif
+ /* To avoid stressing percpu allocator, do this once we're unique. */
+ err = percpu_modalloc(mod, info);
+ if (err)
+ goto unlink_mod;
+
/* Now module is in final location, initialize linked lists, etc. */
err = module_unload_init(mod);
if (err)
goto unlink_mod;
+ init_param_lock(mod);
+
/* Now we've got everything in the final locations, we can
* find optional sections. */
- find_module_sections(mod, info);
+ err = find_module_sections(mod, info);
+ if (err)
+ goto free_unload;
err = check_module_license_and_versions(mod);
if (err)
dynamic_debug_setup(info->debug, info->num_debug);
+ /* Ftrace init must be called in the MODULE_STATE_UNFORMED state */
+ ftrace_module_init(mod);
+
/* Finally it's fully formed, ready to start executing. */
err = complete_formation(mod, info);
if (err)
goto ddebug_cleanup;
/* Module is ready to execute: parsing args may do that. */
- err = parse_args(mod->name, mod->args, mod->kp, mod->num_kp,
- -32768, 32767, &ddebug_dyndbg_module_param_cb);
- if (err < 0)
+ after_dashes = parse_args(mod->name, mod->args, mod->kp, mod->num_kp,
+ -32768, 32767, mod,
+ unknown_module_param_cb);
+ if (IS_ERR(after_dashes)) {
+ err = PTR_ERR(after_dashes);
goto bug_cleanup;
+ } else if (after_dashes) {
+ pr_warn("%s: parameters '%s' after `--' ignored\n",
+ mod->name, after_dashes);
+ }
/* Link in to syfs. */
err = mod_sysfs_setup(mod, info, mod->kp, mod->num_kp);
mutex_lock(&module_mutex);
module_bug_cleanup(mod);
mutex_unlock(&module_mutex);
+
+ blocking_notifier_call_chain(&module_notify_list,
+ MODULE_STATE_GOING, mod);
+
+ /* we can't deallocate the module until we clear memory protection */
+ unset_module_init_ro_nx(mod);
+ unset_module_core_ro_nx(mod);
+
ddebug_cleanup:
dynamic_debug_remove(info->debug);
synchronize_sched();
mutex_lock(&module_mutex);
/* Unlink carefully: kallsyms could be walking list. */
list_del_rcu(&mod->list);
+ mod_tree_remove(mod);
wake_up_all(&module_wq);
+ /* Wait for RCU-sched synchronizing before releasing mod->list. */
+ synchronize_sched();
mutex_unlock(&module_mutex);
free_module:
+ /*
+ * Ftrace needs to clean up what it initialized.
+ * This does nothing if ftrace_module_init() wasn't called,
+ * but it must be called outside of module_mutex.
+ */
+ ftrace_release_mod(mod);
+ /* Free lock-classes; relies on the preceding sync_rcu() */
+ lockdep_free_key_range(mod->module_core, mod->core_size);
+
module_deallocate(mod, info);
free_copy:
free_copy(info);
*/
static inline int is_arm_mapping_symbol(const char *str)
{
- return str[0] == '$' && strchr("atd", str[1])
+ if (str[0] == '.' && str[1] == 'L')
+ return true;
+ return str[0] == '$' && strchr("axtd", str[1])
&& (str[2] == '\0' || str[2] == '.');
}
+static const char *symname(struct mod_kallsyms *kallsyms, unsigned int symnum)
+{
+ return kallsyms->strtab + kallsyms->symtab[symnum].st_name;
+}
+
static const char *get_ksymbol(struct module *mod,
unsigned long addr,
unsigned long *size,
{
unsigned int i, best = 0;
unsigned long nextval;
+ struct mod_kallsyms *kallsyms = rcu_dereference_sched(mod->kallsyms);
/* At worse, next value is at end of module */
if (within_module_init(addr, mod))
/* Scan for closest preceding symbol, and next symbol. (ELF
starts real symbols at 1). */
- for (i = 1; i < mod->num_symtab; i++) {
- if (mod->symtab[i].st_shndx == SHN_UNDEF)
+ for (i = 1; i < kallsyms->num_symtab; i++) {
+ if (kallsyms->symtab[i].st_shndx == SHN_UNDEF)
continue;
/* We ignore unnamed symbols: they're uninformative
* and inserted at a whim. */
- if (mod->symtab[i].st_value <= addr
- && mod->symtab[i].st_value > mod->symtab[best].st_value
- && *(mod->strtab + mod->symtab[i].st_name) != '\0'
- && !is_arm_mapping_symbol(mod->strtab + mod->symtab[i].st_name))
+ if (*symname(kallsyms, i) == '\0'
+ || is_arm_mapping_symbol(symname(kallsyms, i)))
+ continue;
+
+ if (kallsyms->symtab[i].st_value <= addr
+ && kallsyms->symtab[i].st_value > kallsyms->symtab[best].st_value)
best = i;
- if (mod->symtab[i].st_value > addr
- && mod->symtab[i].st_value < nextval
- && *(mod->strtab + mod->symtab[i].st_name) != '\0'
- && !is_arm_mapping_symbol(mod->strtab + mod->symtab[i].st_name))
- nextval = mod->symtab[i].st_value;
+ if (kallsyms->symtab[i].st_value > addr
+ && kallsyms->symtab[i].st_value < nextval)
+ nextval = kallsyms->symtab[i].st_value;
}
if (!best)
return NULL;
if (size)
- *size = nextval - mod->symtab[best].st_value;
+ *size = nextval - kallsyms->symtab[best].st_value;
if (offset)
- *offset = addr - mod->symtab[best].st_value;
- return mod->strtab + mod->symtab[best].st_name;
+ *offset = addr - kallsyms->symtab[best].st_value;
+ return symname(kallsyms, best);
}
/* For kallsyms to ask for address resolution. NULL means not found. Careful
char **modname,
char *namebuf)
{
- struct module *mod;
const char *ret = NULL;
+ struct module *mod;
preempt_disable();
- list_for_each_entry_rcu(mod, &modules, list) {
- if (mod->state == MODULE_STATE_UNFORMED)
- continue;
- if (within_module_init(addr, mod) ||
- within_module_core(addr, mod)) {
- if (modname)
- *modname = mod->name;
- ret = get_ksymbol(mod, addr, size, offset);
- break;
- }
+ mod = __module_address(addr);
+ if (mod) {
+ if (modname)
+ *modname = mod->name;
+ ret = get_ksymbol(mod, addr, size, offset);
}
/* Make a copy in here where it's safe */
if (ret) {
ret = namebuf;
}
preempt_enable();
+
return ret;
}
list_for_each_entry_rcu(mod, &modules, list) {
if (mod->state == MODULE_STATE_UNFORMED)
continue;
- if (within_module_init(addr, mod) ||
- within_module_core(addr, mod)) {
+ if (within_module(addr, mod)) {
const char *sym;
sym = get_ksymbol(mod, addr, NULL, NULL);
list_for_each_entry_rcu(mod, &modules, list) {
if (mod->state == MODULE_STATE_UNFORMED)
continue;
- if (within_module_init(addr, mod) ||
- within_module_core(addr, mod)) {
+ if (within_module(addr, mod)) {
const char *sym;
sym = get_ksymbol(mod, addr, size, offset);
preempt_disable();
list_for_each_entry_rcu(mod, &modules, list) {
+ struct mod_kallsyms *kallsyms;
+
if (mod->state == MODULE_STATE_UNFORMED)
continue;
- if (symnum < mod->num_symtab) {
- *value = mod->symtab[symnum].st_value;
- *type = mod->symtab[symnum].st_info;
- strlcpy(name, mod->strtab + mod->symtab[symnum].st_name,
- KSYM_NAME_LEN);
+ kallsyms = rcu_dereference_sched(mod->kallsyms);
+ if (symnum < kallsyms->num_symtab) {
+ *value = kallsyms->symtab[symnum].st_value;
+ *type = kallsyms->symtab[symnum].st_info;
+ strlcpy(name, symname(kallsyms, symnum), KSYM_NAME_LEN);
strlcpy(module_name, mod->name, MODULE_NAME_LEN);
*exported = is_exported(name, *value, mod);
preempt_enable();
return 0;
}
- symnum -= mod->num_symtab;
+ symnum -= kallsyms->num_symtab;
}
preempt_enable();
return -ERANGE;
static unsigned long mod_find_symname(struct module *mod, const char *name)
{
unsigned int i;
+ struct mod_kallsyms *kallsyms = rcu_dereference_sched(mod->kallsyms);
- for (i = 0; i < mod->num_symtab; i++)
- if (strcmp(name, mod->strtab+mod->symtab[i].st_name) == 0 &&
- mod->symtab[i].st_info != 'U')
- return mod->symtab[i].st_value;
+ for (i = 0; i < kallsyms->num_symtab; i++)
+ if (strcmp(name, symname(kallsyms, i)) == 0 &&
+ kallsyms->symtab[i].st_info != 'U')
+ return kallsyms->symtab[i].st_value;
return 0;
}
/* Don't lock: we're in enough trouble already. */
preempt_disable();
if ((colon = strchr(name, ':')) != NULL) {
- *colon = '\0';
- if ((mod = find_module(name)) != NULL)
+ if ((mod = find_module_all(name, colon - name, false)) != NULL)
ret = mod_find_symname(mod, colon+1);
- *colon = ':';
} else {
list_for_each_entry_rcu(mod, &modules, list) {
if (mod->state == MODULE_STATE_UNFORMED)
unsigned int i;
int ret;
+ module_assert_mutex();
+
list_for_each_entry(mod, &modules, list) {
+ /* We hold module_mutex: no need for rcu_dereference_sched */
+ struct mod_kallsyms *kallsyms = mod->kallsyms;
+
if (mod->state == MODULE_STATE_UNFORMED)
continue;
- for (i = 0; i < mod->num_symtab; i++) {
- ret = fn(data, mod->strtab + mod->symtab[i].st_name,
- mod, mod->symtab[i].st_value);
+ for (i = 0; i < kallsyms->num_symtab; i++) {
+ ret = fn(data, symname(kallsyms, i),
+ mod, kallsyms->symtab[i].st_value);
if (ret != 0)
return ret;
}
/* Informative for users. */
seq_printf(m, " %s",
- mod->state == MODULE_STATE_GOING ? "Unloading":
- mod->state == MODULE_STATE_COMING ? "Loading":
+ mod->state == MODULE_STATE_GOING ? "Unloading" :
+ mod->state == MODULE_STATE_COMING ? "Loading" :
"Live");
/* Used by oprofile and other similar tools. */
seq_printf(m, " 0x%pK", mod->module_core);
if (mod->taints)
seq_printf(m, " %s", module_flags(mod, buf));
- seq_printf(m, "\n");
+ seq_puts(m, "\n");
return 0;
}
if (addr < module_addr_min || addr > module_addr_max)
return NULL;
- list_for_each_entry_rcu(mod, &modules, list) {
+ module_assert_mutex_or_preempt();
+
+ mod = mod_find(addr);
+ if (mod) {
+ BUG_ON(!within_module(addr, mod));
if (mod->state == MODULE_STATE_UNFORMED)
- continue;
- if (within_module_core(addr, mod)
- || within_module_init(addr, mod))
- return mod;
+ mod = NULL;
}
- return NULL;
+ return mod;
}
EXPORT_SYMBOL_GPL(__module_address);
list_for_each_entry_rcu(mod, &modules, list) {
if (mod->state == MODULE_STATE_UNFORMED)
continue;
- printk(" %s%s", mod->name, module_flags(mod, buf));
+ pr_cont(" %s%s", mod->name, module_flags(mod, buf));
}
preempt_enable();
if (last_unloaded_module[0])
- printk(" [last unloaded: %s]", last_unloaded_module);
- printk("\n");
+ pr_cont(" [last unloaded: %s]", last_unloaded_module);
+ pr_cont("\n");
}
#ifdef CONFIG_MODVERSIONS
projects / firefly-linux-kernel-4.4.55.git / blobdiff