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-rw-r--r--kernel/async.c30
-rw-r--r--kernel/audit.c40
-rw-r--r--kernel/audit_tree.c26
-rw-r--r--kernel/audit_watch.c2
-rw-r--r--kernel/auditfilter.c1
-rw-r--r--kernel/auditsc.c20
-rw-r--r--kernel/compat.c23
-rw-r--r--kernel/debug/kdb/kdb_main.c2
-rw-r--r--kernel/fork.c6
-rw-r--r--kernel/module.c181
-rw-r--r--kernel/ptrace.c74
-rw-r--r--kernel/rwsem.c10
-rw-r--r--kernel/sched/core.c3
-rw-r--r--kernel/signal.c24
-rw-r--r--kernel/trace/ftrace.c2
-rw-r--r--kernel/trace/trace.c17
16 files changed, 335 insertions, 126 deletions
diff --git a/kernel/async.c b/kernel/async.c
index 9d31183..6f34904 100644
--- a/kernel/async.c
+++ b/kernel/async.c
@@ -86,18 +86,27 @@ static atomic_t entry_count;
*/
static async_cookie_t __lowest_in_progress(struct async_domain *running)
{
+ async_cookie_t first_running = next_cookie; /* infinity value */
+ async_cookie_t first_pending = next_cookie; /* ditto */
struct async_entry *entry;
+ /*
+ * Both running and pending lists are sorted but not disjoint.
+ * Take the first cookies from both and return the min.
+ */
if (!list_empty(&running->domain)) {
entry = list_first_entry(&running->domain, typeof(*entry), list);
- return entry->cookie;
+ first_running = entry->cookie;
}
- list_for_each_entry(entry, &async_pending, list)
- if (entry->running == running)
- return entry->cookie;
+ list_for_each_entry(entry, &async_pending, list) {
+ if (entry->running == running) {
+ first_pending = entry->cookie;
+ break;
+ }
+ }
- return next_cookie; /* "infinity" value */
+ return min(first_running, first_pending);
}
static async_cookie_t lowest_in_progress(struct async_domain *running)
@@ -118,13 +127,17 @@ static void async_run_entry_fn(struct work_struct *work)
{
struct async_entry *entry =
container_of(work, struct async_entry, work);
+ struct async_entry *pos;
unsigned long flags;
ktime_t uninitialized_var(calltime), delta, rettime;
struct async_domain *running = entry->running;
- /* 1) move self to the running queue */
+ /* 1) move self to the running queue, make sure it stays sorted */
spin_lock_irqsave(&async_lock, flags);
- list_move_tail(&entry->list, &running->domain);
+ list_for_each_entry_reverse(pos, &running->domain, list)
+ if (entry->cookie < pos->cookie)
+ break;
+ list_move_tail(&entry->list, &pos->list);
spin_unlock_irqrestore(&async_lock, flags);
/* 2) run (and print duration) */
@@ -196,6 +209,9 @@ static async_cookie_t __async_schedule(async_func_ptr *ptr, void *data, struct a
atomic_inc(&entry_count);
spin_unlock_irqrestore(&async_lock, flags);
+ /* mark that this task has queued an async job, used by module init */
+ current->flags |= PF_USED_ASYNC;
+
/* schedule for execution */
queue_work(system_unbound_wq, &entry->work);
diff --git a/kernel/audit.c b/kernel/audit.c
index 40414e9..d596e53 100644
--- a/kernel/audit.c
+++ b/kernel/audit.c
@@ -272,6 +272,8 @@ static int audit_log_config_change(char *function_name, int new, int old,
int rc = 0;
ab = audit_log_start(NULL, GFP_KERNEL, AUDIT_CONFIG_CHANGE);
+ if (unlikely(!ab))
+ return rc;
audit_log_format(ab, "%s=%d old=%d auid=%u ses=%u", function_name, new,
old, from_kuid(&init_user_ns, loginuid), sessionid);
if (sid) {
@@ -619,6 +621,8 @@ static int audit_log_common_recv_msg(struct audit_buffer **ab, u16 msg_type,
}
*ab = audit_log_start(NULL, GFP_KERNEL, msg_type);
+ if (unlikely(!*ab))
+ return rc;
audit_log_format(*ab, "pid=%d uid=%u auid=%u ses=%u",
task_tgid_vnr(current),
from_kuid(&init_user_ns, current_uid()),
@@ -1097,6 +1101,23 @@ static inline void audit_get_stamp(struct audit_context *ctx,
}
}
+/*
+ * Wait for auditd to drain the queue a little
+ */
+static void wait_for_auditd(unsigned long sleep_time)
+{
+ DECLARE_WAITQUEUE(wait, current);
+ set_current_state(TASK_INTERRUPTIBLE);
+ add_wait_queue(&audit_backlog_wait, &wait);
+
+ if (audit_backlog_limit &&
+ skb_queue_len(&audit_skb_queue) > audit_backlog_limit)
+ schedule_timeout(sleep_time);
+
+ __set_current_state(TASK_RUNNING);
+ remove_wait_queue(&audit_backlog_wait, &wait);
+}
+
/* Obtain an audit buffer. This routine does locking to obtain the
* audit buffer, but then no locking is required for calls to
* audit_log_*format. If the tsk is a task that is currently in a
@@ -1142,20 +1163,13 @@ struct audit_buffer *audit_log_start(struct audit_context *ctx, gfp_t gfp_mask,
while (audit_backlog_limit
&& skb_queue_len(&audit_skb_queue) > audit_backlog_limit + reserve) {
- if (gfp_mask & __GFP_WAIT && audit_backlog_wait_time
- && time_before(jiffies, timeout_start + audit_backlog_wait_time)) {
+ if (gfp_mask & __GFP_WAIT && audit_backlog_wait_time) {
+ unsigned long sleep_time;
- /* Wait for auditd to drain the queue a little */
- DECLARE_WAITQUEUE(wait, current);
- set_current_state(TASK_INTERRUPTIBLE);
- add_wait_queue(&audit_backlog_wait, &wait);
-
- if (audit_backlog_limit &&
- skb_queue_len(&audit_skb_queue) > audit_backlog_limit)
- schedule_timeout(timeout_start + audit_backlog_wait_time - jiffies);
-
- __set_current_state(TASK_RUNNING);
- remove_wait_queue(&audit_backlog_wait, &wait);
+ sleep_time = timeout_start + audit_backlog_wait_time -
+ jiffies;
+ if ((long)sleep_time > 0)
+ wait_for_auditd(sleep_time);
continue;
}
if (audit_rate_check() && printk_ratelimit())
diff --git a/kernel/audit_tree.c b/kernel/audit_tree.c
index e81175e..642a89c 100644
--- a/kernel/audit_tree.c
+++ b/kernel/audit_tree.c
@@ -449,11 +449,26 @@ static int tag_chunk(struct inode *inode, struct audit_tree *tree)
return 0;
}
+static void audit_log_remove_rule(struct audit_krule *rule)
+{
+ struct audit_buffer *ab;
+
+ ab = audit_log_start(NULL, GFP_KERNEL, AUDIT_CONFIG_CHANGE);
+ if (unlikely(!ab))
+ return;
+ audit_log_format(ab, "op=");
+ audit_log_string(ab, "remove rule");
+ audit_log_format(ab, " dir=");
+ audit_log_untrustedstring(ab, rule->tree->pathname);
+ audit_log_key(ab, rule->filterkey);
+ audit_log_format(ab, " list=%d res=1", rule->listnr);
+ audit_log_end(ab);
+}
+
static void kill_rules(struct audit_tree *tree)
{
struct audit_krule *rule, *next;
struct audit_entry *entry;
- struct audit_buffer *ab;
list_for_each_entry_safe(rule, next, &tree->rules, rlist) {
entry = container_of(rule, struct audit_entry, rule);
@@ -461,14 +476,7 @@ static void kill_rules(struct audit_tree *tree)
list_del_init(&rule->rlist);
if (rule->tree) {
/* not a half-baked one */
- ab = audit_log_start(NULL, GFP_KERNEL, AUDIT_CONFIG_CHANGE);
- audit_log_format(ab, "op=");
- audit_log_string(ab, "remove rule");
- audit_log_format(ab, " dir=");
- audit_log_untrustedstring(ab, rule->tree->pathname);
- audit_log_key(ab, rule->filterkey);
- audit_log_format(ab, " list=%d res=1", rule->listnr);
- audit_log_end(ab);
+ audit_log_remove_rule(rule);
rule->tree = NULL;
list_del_rcu(&entry->list);
list_del(&entry->rule.list);
diff --git a/kernel/audit_watch.c b/kernel/audit_watch.c
index 4a599f6..22831c4 100644
--- a/kernel/audit_watch.c
+++ b/kernel/audit_watch.c
@@ -240,6 +240,8 @@ static void audit_watch_log_rule_change(struct audit_krule *r, struct audit_watc
if (audit_enabled) {
struct audit_buffer *ab;
ab = audit_log_start(NULL, GFP_NOFS, AUDIT_CONFIG_CHANGE);
+ if (unlikely(!ab))
+ return;
audit_log_format(ab, "auid=%u ses=%u op=",
from_kuid(&init_user_ns, audit_get_loginuid(current)),
audit_get_sessionid(current));
diff --git a/kernel/auditfilter.c b/kernel/auditfilter.c
index 7f19f23..f9fc54b 100644
--- a/kernel/auditfilter.c
+++ b/kernel/auditfilter.c
@@ -1144,7 +1144,6 @@ static void audit_log_rule_change(kuid_t loginuid, u32 sessionid, u32 sid,
* audit_receive_filter - apply all rules to the specified message type
* @type: audit message type
* @pid: target pid for netlink audit messages
- * @uid: target uid for netlink audit messages
* @seq: netlink audit message sequence (serial) number
* @data: payload data
* @datasz: size of payload data
diff --git a/kernel/auditsc.c b/kernel/auditsc.c
index e37e6a1..a371f85 100644
--- a/kernel/auditsc.c
+++ b/kernel/auditsc.c
@@ -1464,14 +1464,14 @@ static void show_special(struct audit_context *context, int *call_panic)
audit_log_end(ab);
ab = audit_log_start(context, GFP_KERNEL,
AUDIT_IPC_SET_PERM);
+ if (unlikely(!ab))
+ return;
audit_log_format(ab,
"qbytes=%lx ouid=%u ogid=%u mode=%#ho",
context->ipc.qbytes,
context->ipc.perm_uid,
context->ipc.perm_gid,
context->ipc.perm_mode);
- if (!ab)
- return;
}
break; }
case AUDIT_MQ_OPEN: {
@@ -2675,7 +2675,7 @@ void __audit_mmap_fd(int fd, int flags)
context->type = AUDIT_MMAP;
}
-static void audit_log_abend(struct audit_buffer *ab, char *reason, long signr)
+static void audit_log_task(struct audit_buffer *ab)
{
kuid_t auid, uid;
kgid_t gid;
@@ -2693,6 +2693,11 @@ static void audit_log_abend(struct audit_buffer *ab, char *reason, long signr)
audit_log_task_context(ab);
audit_log_format(ab, " pid=%d comm=", current->pid);
audit_log_untrustedstring(ab, current->comm);
+}
+
+static void audit_log_abend(struct audit_buffer *ab, char *reason, long signr)
+{
+ audit_log_task(ab);
audit_log_format(ab, " reason=");
audit_log_string(ab, reason);
audit_log_format(ab, " sig=%ld", signr);
@@ -2715,6 +2720,8 @@ void audit_core_dumps(long signr)
return;
ab = audit_log_start(NULL, GFP_KERNEL, AUDIT_ANOM_ABEND);
+ if (unlikely(!ab))
+ return;
audit_log_abend(ab, "memory violation", signr);
audit_log_end(ab);
}
@@ -2723,8 +2730,11 @@ void __audit_seccomp(unsigned long syscall, long signr, int code)
{
struct audit_buffer *ab;
- ab = audit_log_start(NULL, GFP_KERNEL, AUDIT_ANOM_ABEND);
- audit_log_abend(ab, "seccomp", signr);
+ ab = audit_log_start(NULL, GFP_KERNEL, AUDIT_SECCOMP);
+ if (unlikely(!ab))
+ return;
+ audit_log_task(ab);
+ audit_log_format(ab, " sig=%ld", signr);
audit_log_format(ab, " syscall=%ld", syscall);
audit_log_format(ab, " compat=%d", is_compat_task());
audit_log_format(ab, " ip=0x%lx", KSTK_EIP(current));
diff --git a/kernel/compat.c b/kernel/compat.c
index f6150e9..36700e9 100644
--- a/kernel/compat.c
+++ b/kernel/compat.c
@@ -535,9 +535,11 @@ asmlinkage long compat_sys_getrusage(int who, struct compat_rusage __user *ru)
return 0;
}
-asmlinkage long
-compat_sys_wait4(compat_pid_t pid, compat_uint_t __user *stat_addr, int options,
- struct compat_rusage __user *ru)
+COMPAT_SYSCALL_DEFINE4(wait4,
+ compat_pid_t, pid,
+ compat_uint_t __user *, stat_addr,
+ int, options,
+ struct compat_rusage __user *, ru)
{
if (!ru) {
return sys_wait4(pid, stat_addr, options, NULL);
@@ -564,9 +566,10 @@ compat_sys_wait4(compat_pid_t pid, compat_uint_t __user *stat_addr, int options,
}
}
-asmlinkage long compat_sys_waitid(int which, compat_pid_t pid,
- struct compat_siginfo __user *uinfo, int options,
- struct compat_rusage __user *uru)
+COMPAT_SYSCALL_DEFINE5(waitid,
+ int, which, compat_pid_t, pid,
+ struct compat_siginfo __user *, uinfo, int, options,
+ struct compat_rusage __user *, uru)
{
siginfo_t info;
struct rusage ru;
@@ -584,7 +587,11 @@ asmlinkage long compat_sys_waitid(int which, compat_pid_t pid,
return ret;
if (uru) {
- ret = put_compat_rusage(&ru, uru);
+ /* sys_waitid() overwrites everything in ru */
+ if (COMPAT_USE_64BIT_TIME)
+ ret = copy_to_user(uru, &ru, sizeof(ru));
+ else
+ ret = put_compat_rusage(&ru, uru);
if (ret)
return ret;
}
@@ -994,7 +1001,7 @@ compat_sys_rt_sigtimedwait (compat_sigset_t __user *uthese,
sigset_from_compat(&s, &s32);
if (uts) {
- if (get_compat_timespec(&t, uts))
+ if (compat_get_timespec(&t, uts))
return -EFAULT;
}
diff --git a/kernel/debug/kdb/kdb_main.c b/kernel/debug/kdb/kdb_main.c
index 4d5f8d5..8875254 100644
--- a/kernel/debug/kdb/kdb_main.c
+++ b/kernel/debug/kdb/kdb_main.c
@@ -1970,6 +1970,8 @@ static int kdb_lsmod(int argc, const char **argv)
kdb_printf("Module Size modstruct Used by\n");
list_for_each_entry(mod, kdb_modules, list) {
+ if (mod->state == MODULE_STATE_UNFORMED)
+ continue;
kdb_printf("%-20s%8u 0x%p ", mod->name,
mod->core_size, (void *)mod);
diff --git a/kernel/fork.c b/kernel/fork.c
index 65ca6d2..c535f33 100644
--- a/kernel/fork.c
+++ b/kernel/fork.c
@@ -1668,8 +1668,10 @@ SYSCALL_DEFINE5(clone, unsigned long, clone_flags, unsigned long, newsp,
int, tls_val)
#endif
{
- return do_fork(clone_flags, newsp, 0,
- parent_tidptr, child_tidptr);
+ long ret = do_fork(clone_flags, newsp, 0, parent_tidptr, child_tidptr);
+ asmlinkage_protect(5, ret, clone_flags, newsp,
+ parent_tidptr, child_tidptr, tls_val);
+ return ret;
}
#endif
diff --git a/kernel/module.c b/kernel/module.c
index 250092c..eab0827 100644
--- a/kernel/module.c
+++ b/kernel/module.c
@@ -188,6 +188,7 @@ struct load_info {
ongoing or failed initialization etc. */
static inline int strong_try_module_get(struct module *mod)
{
+ BUG_ON(mod && mod->state == MODULE_STATE_UNFORMED);
if (mod && mod->state == MODULE_STATE_COMING)
return -EBUSY;
if (try_module_get(mod))
@@ -343,6 +344,9 @@ bool each_symbol_section(bool (*fn)(const struct symsearch *arr,
#endif
};
+ if (mod->state == MODULE_STATE_UNFORMED)
+ continue;
+
if (each_symbol_in_section(arr, ARRAY_SIZE(arr), mod, fn, data))
return true;
}
@@ -450,16 +454,24 @@ const struct kernel_symbol *find_symbol(const char *name,
EXPORT_SYMBOL_GPL(find_symbol);
/* Search for module by name: must hold module_mutex. */
-struct module *find_module(const char *name)
+static struct module *find_module_all(const char *name,
+ bool even_unformed)
{
struct module *mod;
list_for_each_entry(mod, &modules, list) {
+ if (!even_unformed && mod->state == MODULE_STATE_UNFORMED)
+ continue;
if (strcmp(mod->name, name) == 0)
return mod;
}
return NULL;
}
+
+struct module *find_module(const char *name)
+{
+ return find_module_all(name, false);
+}
EXPORT_SYMBOL_GPL(find_module);
#ifdef CONFIG_SMP
@@ -525,6 +537,8 @@ bool is_module_percpu_address(unsigned long addr)
preempt_disable();
list_for_each_entry_rcu(mod, &modules, list) {
+ if (mod->state == MODULE_STATE_UNFORMED)
+ continue;
if (!mod->percpu_size)
continue;
for_each_possible_cpu(cpu) {
@@ -1048,6 +1062,8 @@ static ssize_t show_initstate(struct module_attribute *mattr,
case MODULE_STATE_GOING:
state = "going";
break;
+ default:
+ BUG();
}
return sprintf(buffer, "%s\n", state);
}
@@ -1786,6 +1802,8 @@ void set_all_modules_text_rw(void)
mutex_lock(&module_mutex);
list_for_each_entry_rcu(mod, &modules, list) {
+ if (mod->state == MODULE_STATE_UNFORMED)
+ continue;
if ((mod->module_core) && (mod->core_text_size)) {
set_page_attributes(mod->module_core,
mod->module_core + mod->core_text_size,
@@ -1807,6 +1825,8 @@ void set_all_modules_text_ro(void)
mutex_lock(&module_mutex);
list_for_each_entry_rcu(mod, &modules, list) {
+ if (mod->state == MODULE_STATE_UNFORMED)
+ continue;
if ((mod->module_core) && (mod->core_text_size)) {
set_page_attributes(mod->module_core,
mod->module_core + mod->core_text_size,
@@ -2527,6 +2547,13 @@ static int copy_module_from_fd(int fd, struct load_info *info)
err = -EFBIG;
goto out;
}
+
+ /* Don't hand 0 to vmalloc, it whines. */
+ if (stat.size == 0) {
+ err = -EINVAL;
+ goto out;
+ }
+
info->hdr = vmalloc(stat.size);
if (!info->hdr) {
err = -ENOMEM;
@@ -2990,8 +3017,9 @@ static bool finished_loading(const char *name)
bool ret;
mutex_lock(&module_mutex);
- mod = find_module(name);
- ret = !mod || mod->state != MODULE_STATE_COMING;
+ mod = find_module_all(name, true);
+ ret = !mod || mod->state == MODULE_STATE_LIVE
+ || mod->state == MODULE_STATE_GOING;
mutex_unlock(&module_mutex);
return ret;
@@ -3013,6 +3041,12 @@ static int do_init_module(struct module *mod)
{
int ret = 0;
+ /*
+ * We want to find out whether @mod uses async during init. Clear
+ * PF_USED_ASYNC. async_schedule*() will set it.
+ */
+ current->flags &= ~PF_USED_ASYNC;
+
blocking_notifier_call_chain(&module_notify_list,
MODULE_STATE_COMING, mod);
@@ -3058,8 +3092,25 @@ static int do_init_module(struct module *mod)
blocking_notifier_call_chain(&module_notify_list,
MODULE_STATE_LIVE, mod);
- /* We need to finish all async code before the module init sequence is done */
- async_synchronize_full();
+ /*
+ * We need to finish all async code before the module init sequence
+ * is done. This has potential to deadlock. For example, a newly
+ * detected block device can trigger request_module() of the
+ * default iosched from async probing task. Once userland helper
+ * reaches here, async_synchronize_full() will wait on the async
+ * task waiting on request_module() and deadlock.
+ *
+ * This deadlock is avoided by perfomring async_synchronize_full()
+ * iff module init queued any async jobs. This isn't a full
+ * solution as it will deadlock the same if module loading from
+ * async jobs nests more than once; however, due to the various
+ * constraints, this hack seems to be the best option for now.
+ * Please refer to the following thread for details.
+ *
+ * http://thread.gmane.org/gmane.linux.kernel/1420814
+ */
+ if (current->flags & PF_USED_ASYNC)
+ async_synchronize_full();
mutex_lock(&module_mutex);
/* Drop initial reference. */
@@ -3113,6 +3164,32 @@ static int load_module(struct load_info *info, const char __user *uargs,
goto free_copy;
}
+ /*
+ * We try to place it in the list now to make sure it's unique
+ * before we dedicate too many resources. In particular,
+ * temporary percpu memory exhaustion.
+ */
+ mod->state = MODULE_STATE_UNFORMED;
+again:
+ mutex_lock(&module_mutex);
+ if ((old = find_module_all(mod->name, true)) != NULL) {
+ if (old->state == MODULE_STATE_COMING
+ || old->state == MODULE_STATE_UNFORMED) {
+ /* Wait in case it fails to load. */
+ mutex_unlock(&module_mutex);
+ err = wait_event_interruptible(module_wq,
+ finished_loading(mod->name));
+ if (err)
+ goto free_module;
+ goto again;
+ }
+ err = -EEXIST;
+ mutex_unlock(&module_mutex);
+ goto free_module;
+ }
+ list_add_rcu(&mod->list, &modules);
+ mutex_unlock(&module_mutex);
+
#ifdef CONFIG_MODULE_SIG
mod->sig_ok = info->sig_ok;
if (!mod->sig_ok)
@@ -3122,7 +3199,7 @@ static int load_module(struct load_info *info, const char __user *uargs,
/* Now module is in final location, initialize linked lists, etc. */
err = module_unload_init(mod);
if (err)
- goto free_module;
+ goto unlink_mod;
/* Now we've got everything in the final locations, we can
* find optional sections. */
@@ -3157,54 +3234,33 @@ static int load_module(struct load_info *info, const char __user *uargs,
goto free_arch_cleanup;
}
- /* Mark state as coming so strong_try_module_get() ignores us. */
- mod->state = MODULE_STATE_COMING;
-
- /* Now sew it into the lists so we can get lockdep and oops
- * info during argument parsing. No one should access us, since
- * strong_try_module_get() will fail.
- * lockdep/oops can run asynchronous, so use the RCU list insertion
- * function to insert in a way safe to concurrent readers.
- * The mutex protects against concurrent writers.
- */
-again:
- mutex_lock(&module_mutex);
- if ((old = find_module(mod->name)) != NULL) {
- if (old->state == MODULE_STATE_COMING) {
- /* Wait in case it fails to load. */
- mutex_unlock(&module_mutex);
- err = wait_event_interruptible(module_wq,
- finished_loading(mod->name));
- if (err)
- goto free_arch_cleanup;
- goto again;
- }
- err = -EEXIST;
- goto unlock;
- }
-
- /* This has to be done once we're sure module name is unique. */
dynamic_debug_setup(info->debug, info->num_debug);
- /* Find duplicate symbols */
+ mutex_lock(&module_mutex);
+ /* Find duplicate symbols (must be called under lock). */
err = verify_export_symbols(mod);
if (err < 0)
- goto ddebug;
+ goto ddebug_cleanup;
+ /* This relies on module_mutex for list integrity. */
module_bug_finalize(info->hdr, info->sechdrs, mod);
- list_add_rcu(&mod->list, &modules);
+
+ /* 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);
/* 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)
- goto unlink;
+ goto bug_cleanup;
/* Link in to syfs. */
err = mod_sysfs_setup(mod, info, mod->kp, mod->num_kp);
if (err < 0)
- goto unlink;
+ goto bug_cleanup;
/* Get rid of temporary copy. */
free_copy(info);
@@ -3214,16 +3270,13 @@ again:
return do_init_module(mod);
- unlink:
+ bug_cleanup:
+ /* module_bug_cleanup needs module_mutex protection */
mutex_lock(&module_mutex);
- /* Unlink carefully: kallsyms could be walking list. */
- list_del_rcu(&mod->list);
module_bug_cleanup(mod);
- wake_up_all(&module_wq);
- ddebug:
- dynamic_debug_remove(info->debug);
- unlock:
+ ddebug_cleanup:
mutex_unlock(&module_mutex);
+ dynamic_debug_remove(info->debug);
synchronize_sched();
kfree(mod->args);
free_arch_cleanup:
@@ -3232,6 +3285,12 @@ again:
free_modinfo(mod);
free_unload:
module_unload_free(mod);
+ unlink_mod:
+ mutex_lock(&module_mutex);
+ /* Unlink carefully: kallsyms could be walking list. */
+ list_del_rcu(&mod->list);
+ wake_up_all(&module_wq);
+ mutex_unlock(&module_mutex);
free_module:
module_deallocate(mod, info);
free_copy:
@@ -3354,6 +3413,8 @@ const char *module_address_lookup(unsigned long addr,
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)
@@ -3377,6 +3438,8 @@ int lookup_module_symbol_name(unsigned long addr, char *symname)
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)) {
const char *sym;
@@ -3401,6 +3464,8 @@ int lookup_module_symbol_attrs(unsigned long addr, unsigned long *size,
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)) {
const char *sym;
@@ -3428,6 +3493,8 @@ int module_get_kallsym(unsigned int symnum, unsigned long *value, char *type,
preempt_disable();
list_for_each_entry_rcu(mod, &modules, list) {
+ if (mod->state == MODULE_STATE_UNFORMED)
+ continue;
if (symnum < mod->num_symtab) {
*value = mod->symtab[symnum].st_value;
*type = mod->symtab[symnum].st_info;
@@ -3470,9 +3537,12 @@ unsigned long module_kallsyms_lookup_name(const char *name)
ret = mod_find_symname(mod, colon+1);
*colon = ':';
} else {
- list_for_each_entry_rcu(mod, &modules, list)
+ list_for_each_entry_rcu(mod, &modules, list) {
+ if (mod->state == MODULE_STATE_UNFORMED)
+ continue;
if ((ret = mod_find_symname(mod, name)) != 0)
break;
+ }
}
preempt_enable();
return ret;
@@ -3487,6 +3557,8 @@ int module_kallsyms_on_each_symbol(int (*fn)(void *, const char *,
int ret;
list_for_each_entry(mod, &modules, list) {
+ 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);
@@ -3502,6 +3574,7 @@ static char *module_flags(struct module *mod, char *buf)
{
int bx = 0;
+ BUG_ON(mod->state == MODULE_STATE_UNFORMED);
if (mod->taints ||
mod->state == MODULE_STATE_GOING ||
mod->state == MODULE_STATE_COMING) {
@@ -3543,6 +3616,10 @@ static int m_show(struct seq_file *m, void *p)
struct module *mod = list_entry(p, struct module, list);
char buf[8];
+ /* We always ignore unformed modules. */
+ if (mod->state == MODULE_STATE_UNFORMED)
+ return 0;
+
seq_printf(m, "%s %u",
mod->name, mod->init_size + mod->core_size);
print_unload_info(m, mod);
@@ -3603,6 +3680,8 @@ const struct exception_table_entry *search_module_extables(unsigned long addr)
preempt_disable();
list_for_each_entry_rcu(mod, &modules, list) {
+ if (mod->state == MODULE_STATE_UNFORMED)
+ continue;
if (mod->num_exentries == 0)
continue;
@@ -3651,10 +3730,13 @@ struct module *__module_address(unsigned long addr)
if (addr < module_addr_min || addr > module_addr_max)
return NULL;
- list_for_each_entry_rcu(mod, &modules, list)
+ list_for_each_entry_rcu(mod, &modules, list) {
+ if (mod->state == MODULE_STATE_UNFORMED)
+ continue;
if (within_module_core(addr, mod)
|| within_module_init(addr, mod))
return mod;
+ }
return NULL;
}
EXPORT_SYMBOL_GPL(__module_address);
@@ -3707,8 +3789,11 @@ void print_modules(void)
printk(KERN_DEFAULT "Modules linked in:");
/* Most callers should already have preempt disabled, but make sure */
preempt_disable();
- list_for_each_entry_rcu(mod, &modules, list)
+ list_for_each_entry_rcu(mod, &modules, list) {
+ if (mod->state == MODULE_STATE_UNFORMED)
+ continue;
printk(" %s%s", mod->name, module_flags(mod, buf));
+ }
preempt_enable();
if (last_unloaded_module[0])
printk(" [last unloaded: %s]", last_unloaded_module);
diff --git a/kernel/ptrace.c b/kernel/ptrace.c
index 1599157..6cbeaae 100644
--- a/kernel/ptrace.c
+++ b/kernel/ptrace.c
@@ -117,11 +117,45 @@ void __ptrace_unlink(struct task_struct *child)
* TASK_KILLABLE sleeps.
*/
if (child->jobctl & JOBCTL_STOP_PENDING || task_is_traced(child))
- signal_wake_up(child, task_is_traced(child));
+ ptrace_signal_wake_up(child, true);
spin_unlock(&child->sighand->siglock);
}
+/* Ensure that nothing can wake it up, even SIGKILL */
+static bool ptrace_freeze_traced(struct task_struct *task)
+{
+ bool ret = false;
+
+ /* Lockless, nobody but us can set this flag */
+ if (task->jobctl & JOBCTL_LISTENING)
+ return ret;
+
+ spin_lock_irq(&task->sighand->siglock);
+ if (task_is_traced(task) && !__fatal_signal_pending(task)) {
+ task->state = __TASK_TRACED;
+ ret = true;
+ }
+ spin_unlock_irq(&task->sighand->siglock);
+
+ return ret;
+}
+
+static void ptrace_unfreeze_traced(struct task_struct *task)
+{
+ if (task->state != __TASK_TRACED)
+ return;
+
+ WARN_ON(!task->ptrace || task->parent != current);
+
+ spin_lock_irq(&task->sighand->siglock);
+ if (__fatal_signal_pending(task))
+ wake_up_state(task, __TASK_TRACED);
+ else
+ task->state = TASK_TRACED;
+ spin_unlock_irq(&task->sighand->siglock);
+}
+
/**
* ptrace_check_attach - check whether ptracee is ready for ptrace operation
* @child: ptracee to check for
@@ -139,7 +173,7 @@ void __ptrace_unlink(struct task_struct *child)
* RETURNS:
* 0 on success, -ESRCH if %child is not ready.
*/
-int ptrace_check_attach(struct task_struct *child, bool ignore_state)
+static int ptrace_check_attach(struct task_struct *child, bool ignore_state)
{
int ret = -ESRCH;
@@ -151,24 +185,29 @@ int ptrace_check_attach(struct task_struct *child, bool ignore_state)
* be changed by us so it's not changing right after this.
*/
read_lock(&tasklist_lock);
- if ((child->ptrace & PT_PTRACED) && child->parent == current) {
+ if (child->ptrace && child->parent == current) {
+ WARN_ON(child->state == __TASK_TRACED);
/*
* child->sighand can't be NULL, release_task()
* does ptrace_unlink() before __exit_signal().
*/
- spin_lock_irq(&child->sighand->siglock);
- WARN_ON_ONCE(task_is_stopped(child));
- if (ignore_state || (task_is_traced(child) &&
- !(child->jobctl & JOBCTL_LISTENING)))
+ if (ignore_state || ptrace_freeze_traced(child))
ret = 0;
- spin_unlock_irq(&child->sighand->siglock);
}
read_unlock(&tasklist_lock);
- if (!ret && !ignore_state)
- ret = wait_task_inactive(child, TASK_TRACED) ? 0 : -ESRCH;
+ if (!ret && !ignore_state) {
+ if (!wait_task_inactive(child, __TASK_TRACED)) {
+ /*
+ * This can only happen if may_ptrace_stop() fails and
+ * ptrace_stop() changes ->state back to TASK_RUNNING,
+ * so we should not worry about leaking __TASK_TRACED.
+ */
+ WARN_ON(child->state == __TASK_TRACED);
+ ret = -ESRCH;
+ }
+ }
- /* All systems go.. */
return ret;
}
@@ -317,7 +356,7 @@ static int ptrace_attach(struct task_struct *task, long request,
*/
if (task_is_stopped(task) &&
task_set_jobctl_pending(task, JOBCTL_TRAP_STOP | JOBCTL_TRAPPING))
- signal_wake_up(task, 1);
+ signal_wake_up_state(task, __TASK_STOPPED);
spin_unlock(&task->sighand->siglock);
@@ -737,7 +776,7 @@ int ptrace_request(struct task_struct *child, long request,
* tracee into STOP.
*/
if (likely(task_set_jobctl_pending(child, JOBCTL_TRAP_STOP)))
- signal_wake_up(child, child->jobctl & JOBCTL_LISTENING);
+ ptrace_signal_wake_up(child, child->jobctl & JOBCTL_LISTENING);
unlock_task_sighand(child, &flags);
ret = 0;
@@ -763,7 +802,7 @@ int ptrace_request(struct task_struct *child, long request,
* start of this trap and now. Trigger re-trap.
*/
if (child->jobctl & JOBCTL_TRAP_NOTIFY)
- signal_wake_up(child, true);
+ ptrace_signal_wake_up(child, true);
ret = 0;
}
unlock_task_sighand(child, &flags);
@@ -900,6 +939,8 @@ SYSCALL_DEFINE4(ptrace, long, request, long, pid, unsigned long, addr,
goto out_put_task_struct;
ret = arch_ptrace(child, request, addr, data);
+ if (ret || request != PTRACE_DETACH)
+ ptrace_unfreeze_traced(child);
out_put_task_struct:
put_task_struct(child);
@@ -1039,8 +1080,11 @@ asmlinkage long compat_sys_ptrace(compat_long_t request, compat_long_t pid,
ret = ptrace_check_attach(child, request == PTRACE_KILL ||
request == PTRACE_INTERRUPT);
- if (!ret)
+ if (!ret) {
ret = compat_arch_ptrace(child, request, addr, data);
+ if (ret || request != PTRACE_DETACH)
+ ptrace_unfreeze_traced(child);
+ }
out_put_task_struct:
put_task_struct(child);
diff --git a/kernel/rwsem.c b/kernel/rwsem.c
index 6850f53..b3c6c3f 100644
--- a/kernel/rwsem.c
+++ b/kernel/rwsem.c
@@ -116,6 +116,16 @@ void down_read_nested(struct rw_semaphore *sem, int subclass)
EXPORT_SYMBOL(down_read_nested);
+void _down_write_nest_lock(struct rw_semaphore *sem, struct lockdep_map *nest)
+{
+ might_sleep();
+ rwsem_acquire_nest(&sem->dep_map, 0, 0, nest, _RET_IP_);
+
+ LOCK_CONTENDED(sem, __down_write_trylock, __down_write);
+}
+
+EXPORT_SYMBOL(_down_write_nest_lock);
+
void down_write_nested(struct rw_semaphore *sem, int subclass)
{
might_sleep();
diff --git a/kernel/sched/core.c b/kernel/sched/core.c
index 257002c..26058d0 100644
--- a/kernel/sched/core.c
+++ b/kernel/sched/core.c
@@ -1523,7 +1523,8 @@ out:
*/
int wake_up_process(struct task_struct *p)
{
- return try_to_wake_up(p, TASK_ALL, 0);
+ WARN_ON(task_is_stopped_or_traced(p));
+ return try_to_wake_up(p, TASK_NORMAL, 0);
}
EXPORT_SYMBOL(wake_up_process);
diff --git a/kernel/signal.c b/kernel/signal.c
index 372771e..3d09cf6 100644
--- a/kernel/signal.c
+++ b/kernel/signal.c
@@ -680,23 +680,17 @@ int dequeue_signal(struct task_struct *tsk, sigset_t *mask, siginfo_t *info)
* No need to set need_resched since signal event passing
* goes through ->blocked
*/
-void signal_wake_up(struct task_struct *t, int resume)
+void signal_wake_up_state(struct task_struct *t, unsigned int state)
{
- unsigned int mask;
-
set_tsk_thread_flag(t, TIF_SIGPENDING);
-
/*
- * For SIGKILL, we want to wake it up in the stopped/traced/killable
+ * TASK_WAKEKILL also means wake it up in the stopped/traced/killable
* case. We don't check t->state here because there is a race with it
* executing another processor and just now entering stopped state.
* By using wake_up_state, we ensure the process will wake up and
* handle its death signal.
*/
- mask = TASK_INTERRUPTIBLE;
- if (resume)
- mask |= TASK_WAKEKILL;
- if (!wake_up_state(t, mask))
+ if (!wake_up_state(t, state | TASK_INTERRUPTIBLE))
kick_process(t);
}
@@ -844,7 +838,7 @@ static void ptrace_trap_notify(struct task_struct *t)
assert_spin_locked(&t->sighand->siglock);
task_set_jobctl_pending(t, JOBCTL_TRAP_NOTIFY);
- signal_wake_up(t, t->jobctl & JOBCTL_LISTENING);
+ ptrace_signal_wake_up(t, t->jobctl & JOBCTL_LISTENING);
}
/*
@@ -1800,6 +1794,10 @@ static inline int may_ptrace_stop(void)
* If SIGKILL was already sent before the caller unlocked
* ->siglock we must see ->core_state != NULL. Otherwise it
* is safe to enter schedule().
+ *
+ * This is almost outdated, a task with the pending SIGKILL can't
+ * block in TASK_TRACED. But PTRACE_EVENT_EXIT can be reported
+ * after SIGKILL was already dequeued.
*/
if (unlikely(current->mm->core_state) &&
unlikely(current->mm == current->parent->mm))
@@ -1925,6 +1923,7 @@ static void ptrace_stop(int exit_code, int why, int clear_code, siginfo_t *info)
if (gstop_done)
do_notify_parent_cldstop(current, false, why);
+ /* tasklist protects us from ptrace_freeze_traced() */
__set_current_state(TASK_RUNNING);
if (clear_code)
current->exit_code = 0;
@@ -3116,8 +3115,9 @@ int __save_altstack(stack_t __user *uss, unsigned long sp)
#ifdef CONFIG_COMPAT
#ifdef CONFIG_GENERIC_SIGALTSTACK
-asmlinkage long compat_sys_sigaltstack(const compat_stack_t __user *uss_ptr,
- compat_stack_t __user *uoss_ptr)
+COMPAT_SYSCALL_DEFINE2(sigaltstack,
+ const compat_stack_t __user *, uss_ptr,
+ compat_stack_t __user *, uoss_ptr)
{
stack_t uss, uoss;
int ret;
diff --git a/kernel/trace/ftrace.c b/kernel/trace/ftrace.c
index 3ffe4c5..41473b4 100644
--- a/kernel/trace/ftrace.c
+++ b/kernel/trace/ftrace.c
@@ -3998,7 +3998,7 @@ static int ftrace_module_notify(struct notifier_block *self,
struct notifier_block ftrace_module_nb = {
.notifier_call = ftrace_module_notify,
- .priority = 0,
+ .priority = INT_MAX, /* Run before anything that can use kprobes */
};
extern unsigned long __start_mcount_loc[];
diff --git a/kernel/trace/trace.c b/kernel/trace/trace.c
index e512567..3c13e46 100644
--- a/kernel/trace/trace.c
+++ b/kernel/trace/trace.c
@@ -2899,6 +2899,8 @@ tracing_trace_options_write(struct file *filp, const char __user *ubuf,
if (copy_from_user(&buf, ubuf, cnt))
return -EFAULT;
+ buf[cnt] = 0;
+
trace_set_options(buf);
*ppos += cnt;
@@ -3452,7 +3454,7 @@ static int tracing_wait_pipe(struct file *filp)
return -EINTR;
/*
- * We block until we read something and tracing is enabled.
+ * We block until we read something and tracing is disabled.
* We still block if tracing is disabled, but we have never
* read anything. This allows a user to cat this file, and
* then enable tracing. But after we have read something,
@@ -3460,7 +3462,7 @@ static int tracing_wait_pipe(struct file *filp)
*
* iter->pos will be 0 if we haven't read anything.
*/
- if (tracing_is_enabled() && iter->pos)
+ if (!tracing_is_enabled() && iter->pos)
break;
}
@@ -4815,10 +4817,17 @@ rb_simple_write(struct file *filp, const char __user *ubuf,
return ret;
if (buffer) {
- if (val)
+ mutex_lock(&trace_types_lock);
+ if (val) {
ring_buffer_record_on(buffer);
- else
+ if (current_trace->start)
+ current_trace->start(tr);
+ } else {
ring_buffer_record_off(buffer);
+ if (current_trace->stop)
+ current_trace->stop(tr);
+ }
+ mutex_unlock(&trace_types_lock);
}
(*ppos)++;
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