ip: reassembly: fix use-after-free
When processing the last buffer of a reassembled packet, the current
buffer will be freed and must be reloaded using the updated index.
Type: fix
Change-Id: Ib39e29e60eb527b4cd4828a3aa37d82c8dddd709
Signed-off-by: Benoît Ganne <bganne@cisco.com>
diff --git a/src/vnet/ip/reass/ip4_full_reass.c b/src/vnet/ip/reass/ip4_full_reass.c
index 303f233..f6c0546 100644
--- a/src/vnet/ip/reass/ip4_full_reass.c
+++ b/src/vnet/ip/reass/ip4_full_reass.c
@@ -1224,13 +1224,17 @@
packet_enqueue:
- b0->error = node->errors[error0];
if (bi0 != ~0)
{
to_next[0] = bi0;
to_next += 1;
n_left_to_next -= 1;
+
+ /* bi0 might have been updated by reass_finalize, reload */
+ b0 = vlib_get_buffer (vm, bi0);
+ b0->error = node->errors[error0];
+
if (next0 == IP4_FULL_REASS_NEXT_HANDOFF)
{
if (PREDICT_FALSE (b0->flags & VLIB_BUFFER_IS_TRACED))
@@ -1243,7 +1247,6 @@
}
else if (is_feature && IP4_ERROR_NONE == error0)
{
- b0 = vlib_get_buffer (vm, bi0);
vnet_feature_next (&next0, b0);
}
vlib_validate_buffer_enqueue_x1 (vm, node, next_index,