[PATCH 03/10] of: Correct child specifier used as input of the 2nd nexus node

From: Zijun Hu
Date: Thu Dec 05 2024 - 19:53:58 EST


From: Zijun Hu <quic_zijuhu@xxxxxxxxxxx>

API of_parse_phandle_with_args_map() will use wrong input for nexus node
Nexus_2 as shown below:

Node_1 Nexus_1 Nexus_2
&Nexus_1,arg_1 -> arg_1,&Nexus_2,arg_2' -> &Nexus_2,arg_2 -> arg_2,...
map-pass-thru=<...>

Nexus_1's output arg_2 should be used as input of Nexus_2, but the API
wrongly uses arg_2' instead which != arg_2 due to Nexus_1's map-pass-thru.

Fix by always making @match_array point to @initial_match_array into
which to store nexus output.

Fixes: bd6f2fd5a1d5 ("of: Support parsing phandle argument lists through a nexus node")
Cc: stable@xxxxxxxxxxxxxxx
Signed-off-by: Zijun Hu <quic_zijuhu@xxxxxxxxxxx>
---
drivers/of/base.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/of/base.c b/drivers/of/base.c
index b294924aa31cfed1ec06983f420a445f7fae7394..1c62cda4ebcd9e3dc5f91d10fa68f975226693dd 100644
--- a/drivers/of/base.c
+++ b/drivers/of/base.c
@@ -1542,7 +1542,6 @@ int of_parse_phandle_with_args_map(const struct device_node *np,
* specifier into the out_args structure, keeping the
* bits specified in <list>-map-pass-thru.
*/
- match_array = map - new_size;
for (i = 0; i < new_size; i++) {
__be32 val = *(map - new_size + i);

@@ -1551,6 +1550,7 @@ int of_parse_phandle_with_args_map(const struct device_node *np,
val |= cpu_to_be32(out_args->args[i]) & pass[i];
}

+ initial_match_array[i] = val;
out_args->args[i] = be32_to_cpu(val);
}
out_args->args_count = list_size = new_size;

--
2.34.1