From 82ae1a485ecb6e541134f49ebe3aa322deb60c89 Mon Sep 17 00:00:00 2001 From: Benoît Ganne Date: Wed, 23 Oct 2019 13:53:49 +0200 Subject: ip: reassembly: fix use-after-free MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit 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 (cherry picked from commit cf7803d2e864fb71f14943a544ac309d3d0510cb) --- src/vnet/ip/reass/ip4_full_reass.c | 7 +++++-- src/vnet/ip/reass/ip6_full_reass.c | 8 +++++--- 2 files changed, 10 insertions(+), 5 deletions(-) (limited to 'src/vnet/ip') diff --git a/src/vnet/ip/reass/ip4_full_reass.c b/src/vnet/ip/reass/ip4_full_reass.c index 73e820f5427..a2d08a4909c 100644 --- a/src/vnet/ip/reass/ip4_full_reass.c +++ b/src/vnet/ip/reass/ip4_full_reass.c @@ -1208,13 +1208,17 @@ ip4_full_reass_inline (vlib_main_t * vm, vlib_node_runtime_t * node, 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)) @@ -1233,7 +1237,6 @@ ip4_full_reass_inline (vlib_main_t * vm, vlib_node_runtime_t * node, } 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, diff --git a/src/vnet/ip/reass/ip6_full_reass.c b/src/vnet/ip/reass/ip6_full_reass.c index 10acd0e1eda..6848f59c65c 100644 --- a/src/vnet/ip/reass/ip6_full_reass.c +++ b/src/vnet/ip/reass/ip6_full_reass.c @@ -1168,14 +1168,17 @@ ip6_full_reassembly_inline (vlib_main_t * vm, error0 = IP6_ERROR_REASS_LIMIT_REACHED; } - b0->error = node->errors[error0]; - if (~0 != bi0) { skip_reass: 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 == IP6_FULL_REASSEMBLY_NEXT_HANDOFF) { if (PREDICT_FALSE (b0->flags & VLIB_BUFFER_IS_TRACED)) @@ -1194,7 +1197,6 @@ ip6_full_reassembly_inline (vlib_main_t * vm, } else if (is_feature && IP6_ERROR_NONE == error0) { - b0 = vlib_get_buffer (vm, bi0); vnet_feature_next (&next0, b0); } vlib_validate_buffer_enqueue_x1 (vm, node, next_index, to_next, -- cgit 1.2.3-korg