From: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Date: Fri, 22 Sep 2017 20:00:13 +0000 (-0400)
Subject: Filter: catch shift undefined behavior
X-Git-Tag: v2.11.0-rc1~47
X-Git-Url: https://git.lttng.org./?a=commitdiff_plain;h=ea13ec960f55bac1d08e5ec3523797ccdbde573b;p=lttng-modules.git

Filter: catch shift undefined behavior

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

diff --git a/lttng-filter-interpreter.c b/lttng-filter-interpreter.c
index 5bf0bd60..b1e5ba73 100644
--- a/lttng-filter-interpreter.c
+++ b/lttng-filter-interpreter.c
@@ -990,6 +990,11 @@ uint64_t lttng_filter_interpret_bytecode(void *filter_data,
 		{
 			int64_t res;
 
+			/* Catch undefined behavior. */
+			if (unlikely(estack_ax_v < 0 || estack_ax_v >= 64)) {
+				ret = -EINVAL;
+				goto end;
+			}
 			res = (estack_bx_v >> estack_ax_v);
 			estack_pop(stack, top, ax, bx);
 			estack_ax_v = res;
@@ -1000,6 +1005,11 @@ uint64_t lttng_filter_interpret_bytecode(void *filter_data,
 		{
 			int64_t res;
 
+			/* Catch undefined behavior. */
+			if (unlikely(estack_ax_v < 0 || estack_ax_v >= 64)) {
+				ret = -EINVAL;
+				goto end;
+			}
 			res = (estack_bx_v << estack_ax_v);
 			estack_pop(stack, top, ax, bx);
 			estack_ax_v = res;