From 8bdab83b34efb0b598be4e5b98e4f466ca5f2f80 Mon Sep 17 00:00:00 2001 From: Zhang Chen Date: Fri, 1 Apr 2022 11:47:02 +0800 Subject: [PATCH] net/colo.c: fix segmentation fault when packet is not parsed correctly When COLO use only one vnet_hdr_support parameter between filter-redirector and filter-mirror(or colo-compare), COLO will crash with segmentation fault. Back track as follow: Thread 1 "qemu-system-x86" received signal SIGSEGV, Segmentation fault. 0x0000555555cb200b in eth_get_l2_hdr_length (p=0x0) at /home/tao/project/COLO/colo-qemu/include/net/eth.h:296 296 uint16_t proto = be16_to_cpu(PKT_GET_ETH_HDR(p)->h_proto); (gdb) bt 0 0x0000555555cb200b in eth_get_l2_hdr_length (p=0x0) at /home/tao/project/COLO/colo-qemu/include/net/eth.h:296 1 0x0000555555cb22b4 in parse_packet_early (pkt=0x555556a44840) at net/colo.c:49 2 0x0000555555cb2b91 in is_tcp_packet (pkt=0x555556a44840) at net/filter-rewriter.c:63 So wrong vnet_hdr_len will cause pkt->data become NULL. Add check to raise error and add trace-events to track vnet_hdr_len. Signed-off-by: Tao Xu Signed-off-by: Zhang Chen Reviewed-by: Li Zhijian Signed-off-by: Jason Wang --- net/colo.c | 9 ++++++++- net/trace-events | 1 + 2 files changed, 9 insertions(+), 1 deletion(-) diff --git a/net/colo.c b/net/colo.c index 694f3c93ef..6b0ff562ad 100644 --- a/net/colo.c +++ b/net/colo.c @@ -46,7 +46,14 @@ int parse_packet_early(Packet *pkt) static const uint8_t vlan[] = {0x81, 0x00}; uint8_t *data = pkt->data + pkt->vnet_hdr_len; uint16_t l3_proto; - ssize_t l2hdr_len = eth_get_l2_hdr_length(data); + ssize_t l2hdr_len; + + if (data == NULL) { + trace_colo_proxy_main_vnet_info("This packet is not parsed correctly, " + "pkt->vnet_hdr_len", pkt->vnet_hdr_len); + return 1; + } + l2hdr_len = eth_get_l2_hdr_length(data); if (pkt->size < ETH_HLEN + pkt->vnet_hdr_len) { trace_colo_proxy_main("pkt->size < ETH_HLEN"); diff --git a/net/trace-events b/net/trace-events index d7a17256cc..6af927b4b9 100644 --- a/net/trace-events +++ b/net/trace-events @@ -9,6 +9,7 @@ vhost_user_event(const char *chr, int event) "chr: %s got event: %d" # colo.c colo_proxy_main(const char *chr) ": %s" +colo_proxy_main_vnet_info(const char *sta, int size) ": %s = %d" # colo-compare.c colo_compare_main(const char *chr) ": %s" -- 2.11.0