From 3bfcf396081ace536733b454ff128d53116581e5 Mon Sep 17 00:00:00 2001 From: Kohei Enju Date: Mon, 20 Apr 2026 10:54:23 +0000 Subject: net: validate skb->napi_id in RX tracepoints Since commit 2bd82484bb4c ("xps: fix xps for stacked devices"), skb->napi_id shares storage with sender_cpu. RX tracepoints using net_dev_rx_verbose_template read skb->napi_id directly and can therefore report sender_cpu values as if they were NAPI IDs. For example, on the loopback path this can report 1 as napi_id, where 1 comes from raw_smp_processor_id() + 1 in the XPS path: # bpftrace -e 'tracepoint:net:netif_rx_entry{ print(args->napi_id); }' # taskset -c 0 ping -c 1 ::1 Report only valid NAPI IDs in these tracepoints and use 0 otherwise. Fixes: 2bd82484bb4c ("xps: fix xps for stacked devices") Signed-off-by: Kohei Enju Reviewed-by: Simon Horman Reviewed-by: Jiayuan Chen Link: https://patch.msgid.link/20260420105427.162816-1-kohei@enjuk.jp Signed-off-by: Jakub Kicinski --- include/trace/events/net.h | 4 +++- 1 file changed, 3 insertions(+), 1 deletion(-) (limited to 'include') diff --git a/include/trace/events/net.h b/include/trace/events/net.h index fdd9ad474ce3..dbc2c5598e35 100644 --- a/include/trace/events/net.h +++ b/include/trace/events/net.h @@ -10,6 +10,7 @@ #include #include #include +#include TRACE_EVENT(net_dev_start_xmit, @@ -208,7 +209,8 @@ DECLARE_EVENT_CLASS(net_dev_rx_verbose_template, TP_fast_assign( __assign_str(name); #ifdef CONFIG_NET_RX_BUSY_POLL - __entry->napi_id = skb->napi_id; + __entry->napi_id = napi_id_valid(skb->napi_id) ? + skb->napi_id : 0; #else __entry->napi_id = 0; #endif -- cgit v1.2.3