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-rw-r--r--kernel/kprobes.c39
1 files changed, 27 insertions, 12 deletions
diff --git a/kernel/kprobes.c b/kernel/kprobes.c
index ab257be..90e98e2 100644
--- a/kernel/kprobes.c
+++ b/kernel/kprobes.c
@@ -546,8 +546,14 @@ static void do_free_cleaned_kprobes(void)
struct optimized_kprobe *op, *tmp;
list_for_each_entry_safe(op, tmp, &freeing_list, list) {
- BUG_ON(!kprobe_unused(&op->kp));
list_del_init(&op->list);
+ if (WARN_ON_ONCE(!kprobe_unused(&op->kp))) {
+ /*
+ * This must not happen, but if there is a kprobe
+ * still in use, keep it on kprobes hash list.
+ */
+ continue;
+ }
free_aggr_kprobe(&op->kp);
}
}
@@ -700,11 +706,11 @@ static void unoptimize_kprobe(struct kprobe *p, bool force)
}
/* Cancel unoptimizing for reusing */
-static void reuse_unused_kprobe(struct kprobe *ap)
+static int reuse_unused_kprobe(struct kprobe *ap)
{
struct optimized_kprobe *op;
+ int ret;
- BUG_ON(!kprobe_unused(ap));
/*
* Unused kprobe MUST be on the way of delayed unoptimizing (means
* there is still a relative jump) and disabled.
@@ -714,8 +720,12 @@ static void reuse_unused_kprobe(struct kprobe *ap)
/* Enable the probe again */
ap->flags &= ~KPROBE_FLAG_DISABLED;
/* Optimize it again (remove from op->list) */
- BUG_ON(!kprobe_optready(ap));
+ ret = kprobe_optready(ap);
+ if (ret)
+ return ret;
+
optimize_kprobe(ap);
+ return 0;
}
/* Remove optimized instructions */
@@ -940,11 +950,16 @@ static void __disarm_kprobe(struct kprobe *p, bool reopt)
#define kprobe_disarmed(p) kprobe_disabled(p)
#define wait_for_kprobe_optimizer() do {} while (0)
-/* There should be no unused kprobes can be reused without optimization */
-static void reuse_unused_kprobe(struct kprobe *ap)
+static int reuse_unused_kprobe(struct kprobe *ap)
{
+ /*
+ * If the optimized kprobe is NOT supported, the aggr kprobe is
+ * released at the same time that the last aggregated kprobe is
+ * unregistered.
+ * Thus there should be no chance to reuse unused kprobe.
+ */
printk(KERN_ERR "Error: There should be no unused kprobe here.\n");
- BUG_ON(kprobe_unused(ap));
+ return -EINVAL;
}
static void free_aggr_kprobe(struct kprobe *p)
@@ -1259,8 +1274,6 @@ NOKPROBE_SYMBOL(cleanup_rp_inst);
/* Add the new probe to ap->list */
static int add_new_kprobe(struct kprobe *ap, struct kprobe *p)
{
- BUG_ON(kprobe_gone(ap) || kprobe_gone(p));
-
if (p->post_handler)
unoptimize_kprobe(ap, true); /* Fall back to normal kprobe */
@@ -1318,9 +1331,12 @@ static int register_aggr_kprobe(struct kprobe *orig_p, struct kprobe *p)
goto out;
}
init_aggr_kprobe(ap, orig_p);
- } else if (kprobe_unused(ap))
+ } else if (kprobe_unused(ap)) {
/* This probe is going to die. Rescue it */
- reuse_unused_kprobe(ap);
+ ret = reuse_unused_kprobe(ap);
+ if (ret)
+ goto out;
+ }
if (kprobe_gone(ap)) {
/*
@@ -1704,7 +1720,6 @@ noclean:
return 0;
disarmed:
- BUG_ON(!kprobe_disarmed(ap));
hlist_del_rcu(&ap->hlist);
return 0;
}
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