From: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Date: Fri, 22 Sep 2017 20:00:29 +0000 (-0400)
Subject: Filter: catch shift undefined behavior
X-Git-Tag: v2.11.0-rc1~10
X-Git-Url: https://git.lttng.org./?a=commitdiff_plain;h=3703f1d2e6e5a48c5fe066a7df0d1cc7f76ea4f0;p=lttng-ust.git

Filter: catch shift undefined behavior

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

diff --git a/liblttng-ust/lttng-filter-interpreter.c b/liblttng-ust/lttng-filter-interpreter.c
index 1e7b12a5..1354d9c1 100644
--- a/liblttng-ust/lttng-filter-interpreter.c
+++ b/liblttng-ust/lttng-filter-interpreter.c
@@ -1557,7 +1557,11 @@ uint64_t lttng_filter_interpret_bytecode(void *filter_data,
 				ret = -EINVAL;
 				goto end;
 			}
-
+			/* Catch undefined behavior. */
+			if (caa_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, ax_t, bx_t);
 			estack_ax_v = res;
@@ -1574,7 +1578,11 @@ uint64_t lttng_filter_interpret_bytecode(void *filter_data,
 				ret = -EINVAL;
 				goto end;
 			}
-
+			/* Catch undefined behavior. */
+			if (caa_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, ax_t, bx_t);
 			estack_ax_v = res;