From: Nikita Kalyazin <n.kalyazin@samsung.com>
Date: Tue, 3 Jul 2012 16:12:21 +0000 (+0400)
Subject: Fix of browser instrumentation problem (#363)
X-Git-Tag: Tizen_SDK_2.3~791
X-Git-Url: http://review.tizen.org/git/?a=commitdiff_plain;h=a3af07a302b64b720794f9a7294bd7ceb2b83777;p=kernel%2Fswap-modules.git

Fix of browser instrumentation problem (#363)

The fix is raw and needs for some cleanup.
 - Added do_fork handler (separate from do_exit's one);
 - Added arch_disarm_uprobe() call when deferred uprobe unregistering
   (this matters when a process forks while another one is inside the
   insrumented function).
TODO:
 - Consider all the auxiliary handlers (do_exec, do_exit, do_fork);
 - Consider deferred probes management (disarming).
---

diff --git a/driver/probes_manager.c b/driver/probes_manager.c
index 498f4bf..cf614cb 100644
--- a/driver/probes_manager.c
+++ b/driver/probes_manager.c
@@ -406,7 +406,7 @@ def_jprobe_event_handler (unsigned long arg1, unsigned long arg2, unsigned long
 				 * TODO: call fork specific
 				 * *_probe_pre_code() function
 				 */
-				do_exit_probe_pre_code();
+				do_fork_probe_pre_code();
 			}
 		if (!(probes_flags & PROBE_FLAG_FORK_INSTLD))
 			skip = 1;
diff --git a/driver/us_proc_inst.c b/driver/us_proc_inst.c
index a081708..28a6dd5 100644
--- a/driver/us_proc_inst.c
+++ b/driver/us_proc_inst.c
@@ -1485,6 +1485,39 @@ void do_exit_probe_pre_code (void)
 }
 EXPORT_SYMBOL_GPL(do_exit_probe_pre_code);
 
+void do_fork_probe_pre_code(void)
+{
+	int ret = 0;
+	struct task_struct *task;
+	inst_us_proc_t *task_inst_info = NULL;
+
+	/* if user-space instrumentation is not set */
+	if (!us_proc_info.path) {
+	    return;
+	}
+
+	if (!strcmp(us_proc_info.path,"*")) {
+		task_inst_info = get_task_inst_node(current);
+		if (task_inst_info)  {
+			ret = uninstall_mapped_ips (current, task_inst_info, 1);
+			if (ret != 0) {
+				EPRINTF("failed to uninstall IPs (%d)!", ret);
+			}
+			dbi_unregister_all_uprobes(current, 1);
+		}
+		return;
+	} else {
+		if (current->tgid != us_proc_info.tgid) {
+			return;
+		}
+		ret = uninstall_mapped_ips(current->group_leader, &us_proc_info, 1);
+		if (ret != 0) {
+			EPRINTF("failed to uninstall IPs (%d)!", ret);
+		}
+		us_proc_info.tgid = 0;
+	}
+}
+
 DEFINE_PER_CPU (us_proc_ip_t *, gpCurIp) = NULL;
 EXPORT_PER_CPU_SYMBOL_GPL(gpCurIp);
 DEFINE_PER_CPU(struct pt_regs *, gpUserRegs) = NULL;
diff --git a/driver/us_proc_inst.h b/driver/us_proc_inst.h
index 5a5e595..a9c1dd1 100644
--- a/driver/us_proc_inst.h
+++ b/driver/us_proc_inst.h
@@ -39,6 +39,8 @@ extern void do_page_fault_ret_pre_code (void);
 */
 extern void do_exit_probe_pre_code (void);
 
+extern void do_fork_probe_pre_code (void);
+
 /*
     Detects when target process is killed and removes IPs.
 */
diff --git a/kprobe/dbi_uprobes.c b/kprobe/dbi_uprobes.c
index 536921d..1007c71 100644
--- a/kprobe/dbi_uprobes.c
+++ b/kprobe/dbi_uprobes.c
@@ -269,6 +269,7 @@ void dbi_unregister_uretprobe (struct task_struct *task, struct kretprobe *rp, i
 		{
 			DBPRINTF ("initiating deferred retprobe deletion addr %p", rp->kp.addr);
 			printk ("initiating deferred retprobe deletion addr %p\n", rp->kp.addr);
+			arch_disarm_uprobe(&rp->kp, task);
 			rp2->disarm = 1;
 		}
 		/*