Fix: event notifier: set eval_capture to false for kprobe, kretprobe and uprobe

Trying to capture fields for kprobe, kretprobe, uprobe, event
notifications will end up dereferencing NULL pointers. Prevent execution
of capture code in those cases.

Signed-off-by: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Change-Id: If86b0602351fb42047b184608b28108e9de0d183

diff --git a/src/lttng-kprobes.c b/src/lttng-kprobes.c
index cdaf68ac9d0ffdb550b1a83389589ab5fe15f734..5fa2a11a5db53c71a4ed41de8d64af2f4fd4a1d8 100644 (file)
--- a/src/lttng-kprobes.c
+++ b/src/lttng-kprobes.c
@@ -87,7 +87,7 @@ int lttng_kprobes_event_handler_pre(struct kprobe *p, struct pt_regs *regs)
                        container_of(event, struct lttng_kernel_event_notifier, parent);
                struct lttng_kernel_notification_ctx notif_ctx;
 
-               notif_ctx.eval_capture = LTTNG_READ_ONCE(event_notifier->eval_capture);
+               notif_ctx.eval_capture = false;
                event_notifier->notification_send(event_notifier, NULL, NULL, &notif_ctx);
                break;
        }

diff --git a/src/lttng-kretprobes.c b/src/lttng-kretprobes.c
index 9cb04ad3c6664c95e220f1d23a185f5dc0208cd5..29a50e37091da7e47ac6f46a8d6fd8a85651229c 100644 (file)
--- a/src/lttng-kretprobes.c
+++ b/src/lttng-kretprobes.c
@@ -116,7 +116,7 @@ int _lttng_kretprobes_handler(struct kretprobe_instance *krpi,
                        container_of(event, struct lttng_kernel_event_notifier, parent);
                struct lttng_kernel_notification_ctx notif_ctx;
 
-               notif_ctx.eval_capture = LTTNG_READ_ONCE(event_notifier->eval_capture);
+               notif_ctx.eval_capture = false;
                event_notifier->notification_send(event_notifier, NULL, NULL, &notif_ctx);
                break;
        }

diff --git a/src/lttng-uprobes.c b/src/lttng-uprobes.c
index 63a6595f1b66b02dc0c7d853bf9b2f202805e541..8144a49e264457e9ce226910334e29e28321a821 100644 (file)
--- a/src/lttng-uprobes.c
+++ b/src/lttng-uprobes.c
@@ -101,7 +101,7 @@ int lttng_uprobes_event_handler_pre(struct uprobe_consumer *uc, struct pt_regs *
                        container_of(event, struct lttng_kernel_event_notifier, parent);
                struct lttng_kernel_notification_ctx notif_ctx;
 
-               notif_ctx.eval_capture = LTTNG_READ_ONCE(event_notifier->eval_capture);
+               notif_ctx.eval_capture = false;
                event_notifier->notification_send(event_notifier, NULL, NULL, &notif_ctx);
                break;
        }