X-Git-Url: https://git.openpandora.org/cgi-bin/gitweb.cgi?p=pandora-kernel.git;a=blobdiff_plain;f=kernel%2Fkprobes.c;h=ec1748679b45105615776df20bec18dd14cc02f7;hp=e5d84644823b4094a4e6c629985daddd753bdd19;hb=4cecd7e369e1b252db1d64451462221b362eed1c;hpb=3cdc3acc62527ab9544c2820b5e5da482a105240

diff --git a/kernel/kprobes.c b/kernel/kprobes.c
index e5d84644823b..ec1748679b45 100644
--- a/kernel/kprobes.c
+++ b/kernel/kprobes.c
@@ -53,6 +53,9 @@
 #include <asm/cacheflush.h>
 #include <asm/errno.h>
 #include <asm/uaccess.h>
+#ifdef CONFIG_RETPOLINE
+#include <asm/nospec-branch.h>
+#endif
 
 #define KPROBE_HASH_BITS 6
 #define KPROBE_TABLE_SIZE (1 << KPROBE_HASH_BITS)
@@ -99,6 +102,11 @@ static struct kprobe_blackpoint kprobe_blacklist[] = {
 	{"irq_entries_start",},
 	{"common_interrupt",},
 	{"mcount",},	/* mcount can be called from everywhere */
+#ifdef CONFIG_RETPOLINE
+	{"__indirect_thunk_start",
+	 /* Linker scripts can't set symbol sizes */
+	 .range = (size_t)__indirect_thunk_size},
+#endif
 	{NULL}    /* Terminator */
 };
 
@@ -598,7 +606,7 @@ static __kprobes void kprobe_optimizer(struct work_struct *work)
 }
 
 /* Wait for completing optimization and unoptimization */
-static __kprobes void wait_for_kprobe_optimizer(void)
+__kprobes void wait_for_kprobe_optimizer(void)
 {
 	if (delayed_work_pending(&optimizing_work))
 		wait_for_completion(&optimizer_comp);
@@ -1077,6 +1085,7 @@ void __kprobes kprobe_flush_task(struct task_struct *tk)
 		/* Early boot.  kretprobe_table_locks not yet initialized. */
 		return;
 
+	INIT_HLIST_HEAD(&empty_rp);
 	hash = hash_ptr(tk, KPROBE_HASH_BITS);
 	head = &kretprobe_inst_table[hash];
 	kretprobe_table_lock(hash, &flags);
@@ -1085,7 +1094,6 @@ void __kprobes kprobe_flush_task(struct task_struct *tk)
 			recycle_rp_inst(ri, &empty_rp);
 	}
 	kretprobe_table_unlock(hash, &flags);
-	INIT_HLIST_HEAD(&empty_rp);
 	hlist_for_each_entry_safe(ri, node, tmp, &empty_rp, hlist) {
 		hlist_del(&ri->hlist);
 		kfree(ri);
@@ -1334,8 +1342,10 @@ int __kprobes register_kprobe(struct kprobe *p)
 	if (!kernel_text_address((unsigned long) p->addr) ||
 	    in_kprobes_functions((unsigned long) p->addr) ||
 	    ftrace_text_reserved(p->addr, p->addr) ||
-	    jump_label_text_reserved(p->addr, p->addr))
-		goto fail_with_jump_label;
+	    jump_label_text_reserved(p->addr, p->addr)) {
+		ret = -EINVAL;
+		goto cannot_probe;
+	}
 
 	/* User can pass only KPROBE_FLAG_DISABLED to register_kprobe */
 	p->flags &= KPROBE_FLAG_DISABLED;
@@ -1352,7 +1362,7 @@ int __kprobes register_kprobe(struct kprobe *p)
 		 * its code to prohibit unexpected unloading.
 		 */
 		if (unlikely(!try_module_get(probed_mod)))
-			goto fail_with_jump_label;
+			goto cannot_probe;
 
 		/*
 		 * If the module freed .init.text, we couldn't insert
@@ -1361,7 +1371,7 @@ int __kprobes register_kprobe(struct kprobe *p)
 		if (within_module_init((unsigned long)p->addr, probed_mod) &&
 		    probed_mod->state != MODULE_STATE_COMING) {
 			module_put(probed_mod);
-			goto fail_with_jump_label;
+			goto cannot_probe;
 		}
 		/* ret will be updated by following code */
 	}
@@ -1409,7 +1419,7 @@ out:
 
 	return ret;
 
-fail_with_jump_label:
+cannot_probe:
 	preempt_enable();
 	jump_label_unlock();
 	return ret;
@@ -1673,8 +1683,12 @@ static int __kprobes pre_handler_kretprobe(struct kprobe *p,
 		ri->rp = rp;
 		ri->task = current;
 
-		if (rp->entry_handler && rp->entry_handler(ri, regs))
+		if (rp->entry_handler && rp->entry_handler(ri, regs)) {
+			raw_spin_lock_irqsave(&rp->lock, flags);
+			hlist_add_head(&ri->hlist, &rp->free_instances);
+			raw_spin_unlock_irqrestore(&rp->lock, flags);
 			return 0;
+		}
 
 		arch_prepare_kretprobe(ri, regs);
 
@@ -1980,7 +1994,7 @@ static int __init init_kprobes(void)
 				&size, &offset, &modname, namebuf);
 		if (!symbol_name)
 			kb->range = 0;
-		else
+		else if (size)
 			kb->range = size;
 	}