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Diffstat (limited to 'kernel')
-rw-r--r--kernel/kprobes.c78
1 files changed, 53 insertions, 25 deletions
diff --git a/kernel/kprobes.c b/kernel/kprobes.c
index 2d988141ab85..102160ff5c66 100644
--- a/kernel/kprobes.c
+++ b/kernel/kprobes.c
@@ -1011,23 +1011,27 @@ err_ftrace:
}
/* Caller must lock kprobe_mutex */
-static void disarm_kprobe_ftrace(struct kprobe *p)
+static int disarm_kprobe_ftrace(struct kprobe *p)
{
- int ret;
+ int ret = 0;
- kprobe_ftrace_enabled--;
- if (kprobe_ftrace_enabled == 0) {
+ if (kprobe_ftrace_enabled == 1) {
ret = unregister_ftrace_function(&kprobe_ftrace_ops);
- WARN(ret < 0, "Failed to init kprobe-ftrace (%d)\n", ret);
+ if (WARN(ret < 0, "Failed to unregister kprobe-ftrace (%d)\n", ret))
+ return ret;
}
+
+ kprobe_ftrace_enabled--;
+
ret = ftrace_set_filter_ip(&kprobe_ftrace_ops,
(unsigned long)p->addr, 1, 0);
WARN(ret < 0, "Failed to disarm kprobe-ftrace at %p (%d)\n", p->addr, ret);
+ return ret;
}
#else /* !CONFIG_KPROBES_ON_FTRACE */
#define prepare_kprobe(p) arch_prepare_kprobe(p)
#define arm_kprobe_ftrace(p) (-ENODEV)
-#define disarm_kprobe_ftrace(p) do {} while (0)
+#define disarm_kprobe_ftrace(p) (-ENODEV)
#endif
/* Arm a kprobe with text_mutex */
@@ -1046,18 +1050,18 @@ static int arm_kprobe(struct kprobe *kp)
}
/* Disarm a kprobe with text_mutex */
-static void disarm_kprobe(struct kprobe *kp, bool reopt)
+static int disarm_kprobe(struct kprobe *kp, bool reopt)
{
- if (unlikely(kprobe_ftrace(kp))) {
- disarm_kprobe_ftrace(kp);
- return;
- }
+ if (unlikely(kprobe_ftrace(kp)))
+ return disarm_kprobe_ftrace(kp);
cpus_read_lock();
mutex_lock(&text_mutex);
__disarm_kprobe(kp, reopt);
mutex_unlock(&text_mutex);
cpus_read_unlock();
+
+ return 0;
}
/*
@@ -1639,11 +1643,12 @@ static int aggr_kprobe_disabled(struct kprobe *ap)
static struct kprobe *__disable_kprobe(struct kprobe *p)
{
struct kprobe *orig_p;
+ int ret;
/* Get an original kprobe for return */
orig_p = __get_valid_kprobe(p);
if (unlikely(orig_p == NULL))
- return NULL;
+ return ERR_PTR(-EINVAL);
if (!kprobe_disabled(p)) {
/* Disable probe if it is a child probe */
@@ -1657,8 +1662,13 @@ static struct kprobe *__disable_kprobe(struct kprobe *p)
* should have already been disarmed, so
* skip unneed disarming process.
*/
- if (!kprobes_all_disarmed)
- disarm_kprobe(orig_p, true);
+ if (!kprobes_all_disarmed) {
+ ret = disarm_kprobe(orig_p, true);
+ if (ret) {
+ p->flags &= ~KPROBE_FLAG_DISABLED;
+ return ERR_PTR(ret);
+ }
+ }
orig_p->flags |= KPROBE_FLAG_DISABLED;
}
}
@@ -1675,8 +1685,8 @@ static int __unregister_kprobe_top(struct kprobe *p)
/* Disable kprobe. This will disarm it if needed. */
ap = __disable_kprobe(p);
- if (ap == NULL)
- return -EINVAL;
+ if (IS_ERR(ap))
+ return PTR_ERR(ap);
if (ap == p)
/*
@@ -2109,12 +2119,14 @@ static void kill_kprobe(struct kprobe *p)
int disable_kprobe(struct kprobe *kp)
{
int ret = 0;
+ struct kprobe *p;
mutex_lock(&kprobe_mutex);
/* Disable this kprobe */
- if (__disable_kprobe(kp) == NULL)
- ret = -EINVAL;
+ p = __disable_kprobe(kp);
+ if (IS_ERR(p))
+ ret = PTR_ERR(p);
mutex_unlock(&kprobe_mutex);
return ret;
@@ -2486,34 +2498,50 @@ already_enabled:
return ret;
}
-static void disarm_all_kprobes(void)
+static int disarm_all_kprobes(void)
{
struct hlist_head *head;
struct kprobe *p;
- unsigned int i;
+ unsigned int i, total = 0, errors = 0;
+ int err, ret = 0;
mutex_lock(&kprobe_mutex);
/* If kprobes are already disarmed, just return */
if (kprobes_all_disarmed) {
mutex_unlock(&kprobe_mutex);
- return;
+ return 0;
}
kprobes_all_disarmed = true;
- printk(KERN_INFO "Kprobes globally disabled\n");
for (i = 0; i < KPROBE_TABLE_SIZE; i++) {
head = &kprobe_table[i];
+ /* Disarm all kprobes on a best-effort basis */
hlist_for_each_entry_rcu(p, head, hlist) {
- if (!arch_trampoline_kprobe(p) && !kprobe_disabled(p))
- disarm_kprobe(p, false);
+ if (!arch_trampoline_kprobe(p) && !kprobe_disabled(p)) {
+ err = disarm_kprobe(p, false);
+ if (err) {
+ errors++;
+ ret = err;
+ }
+ total++;
+ }
}
}
+
+ if (errors)
+ pr_warn("Kprobes globally disabled, but failed to disarm %d out of %d probes\n",
+ errors, total);
+ else
+ pr_info("Kprobes globally disabled\n");
+
mutex_unlock(&kprobe_mutex);
/* Wait for disarming all kprobes by optimizer */
wait_for_kprobe_optimizer();
+
+ return ret;
}
/*
@@ -2556,7 +2584,7 @@ static ssize_t write_enabled_file_bool(struct file *file,
case 'n':
case 'N':
case '0':
- disarm_all_kprobes();
+ ret = disarm_all_kprobes();
break;
default:
return -EINVAL;