The ':=' override path in xbc_parse_kv() calls xbc_init_node() to
re-initialize an existing value node but does not check the return
value. If xbc_init_node() fails (data offset out of range), parsing
silently continues with stale node data.
Add the missing error check to match the xbc_add_node() call path
which already checks for failure.
In practice, a bootconfig using ':=' to override a value near the
32KB data limit could silently retain the old value, meaning a
security-relevant boot parameter override (e.g., a trace filter or
debug setting) would not take effect as intended.
Fixes: e5efaeb8a8f5 ("bootconfig: Support mixing a value and subkeys under a key")
Signed-off-by: Josh Law <objecting@objecting.org>
---
lib/bootconfig.c | 3 ++-
1 file changed, 2 insertions(+), 1 deletion(-)
diff --git a/lib/bootconfig.c b/lib/bootconfig.c
index 1adf592cc038..ecc4e8d93547 100644
--- a/lib/bootconfig.c
+++ b/lib/bootconfig.c
@@ -728,7 +728,8 @@ static int __init xbc_parse_kv(char **k, char *v, int op)
if (op == ':') {
unsigned short nidx = child->next;
- xbc_init_node(child, v, XBC_VALUE);
+ if (xbc_init_node(child, v, XBC_VALUE) < 0)
+ return xbc_parse_error("Failed to override value", v);
child->next = nidx; /* keep subkeys */
goto array;
}
--
2.34.1