From a3928f877e7b153dbc243d6329b3777ac75b6004 Mon Sep 17 00:00:00 2001 From: Masami Hiramatsu Date: Thu, 9 Sep 2021 22:36:23 +0900 Subject: [PATCH] tracing/boot: Fix trace_boot_hist_add_array() to check array is value trace_boot_hist_add_array() uses the combination of xbc_node_find_child() and xbc_node_get_child() to get the child node of the key node. But since it missed to check the child node is data node or not, user can pass the subkey node for the array node (anode). To avoid this issue, check the array node is a data node. Actually, there is xbc_node_find_value(node, key, vnode), which ensures the @vnode is a value node, so use it in trace_boot_hist_add_array() to fix this issue. Link: https://lkml.kernel.org/r/163119458308.161018.1516455973625940212.stgit@devnote2 Fixes: e66ed86ca6c5 ("tracing/boot: Add per-event histogram action options") Signed-off-by: Masami Hiramatsu Signed-off-by: Steven Rostedt (VMware) --- kernel/trace/trace_boot.c | 7 +++---- 1 file changed, 3 insertions(+), 4 deletions(-) diff --git a/kernel/trace/trace_boot.c b/kernel/trace/trace_boot.c index 388e65d05978..a6be48b24774 100644 --- a/kernel/trace/trace_boot.c +++ b/kernel/trace/trace_boot.c @@ -219,13 +219,12 @@ static int __init trace_boot_hist_add_array(struct xbc_node *hnode, char **bufp, char *end, const char *key) { - struct xbc_node *knode, *anode; + struct xbc_node *anode; const char *p; char sep; - knode = xbc_node_find_child(hnode, key); - if (knode) { - anode = xbc_node_get_child(knode); + p = xbc_node_find_value(hnode, key, &anode); + if (p) { if (!anode) { pr_err("hist.%s requires value(s).\n", key); return -EINVAL; -- 2.20.1