6.18-stable review patch. If anyone has any objections, please let me know. ------------------ From: Wentao Liang [ Upstream commit 8d604c899f7bd1a76a2eb21c0b706c02878abd36 ] mt76_find_power_limits_node() and mt76_find_channel_node() return nodes with the reference held, but mt76_get_rate_power_limits() overwrites the "txpower-" node reference and never releases the channel node reference, leaking both. Drop the intermediate and the channel node reference on every exit path, and take a reference on the fallback node returned by mt76_find_power_limits_node() so the caller's of_node_put() is balanced. Fixes: 22b980badc0f ("mt76: add functions for parsing rate power limits from DT") Cc: stable@vger.kernel.org Signed-off-by: Wentao Liang Link: https://patch.msgid.link/20260917121944.2150737-1-vulab@iscas.ac.cn Signed-off-by: Felix Fietkau Signed-off-by: Sasha Levin --- drivers/net/wireless/mediatek/mt76/eeprom.c | 17 ++++++++++++----- 1 file changed, 12 insertions(+), 5 deletions(-) diff --git a/drivers/net/wireless/mediatek/mt76/eeprom.c b/drivers/net/wireless/mediatek/mt76/eeprom.c index 6ce8e4af18fe5..281b2c3e9e7cf 100644 --- a/drivers/net/wireless/mediatek/mt76/eeprom.c +++ b/drivers/net/wireless/mediatek/mt76/eeprom.c @@ -224,12 +224,14 @@ mt76_find_power_limits_node(struct mt76_dev *dev) struct property *regd = of_find_property(cur, "regdomain", NULL); if (!country && !regd) { - fallback = cur; + of_node_put(fallback); + fallback = of_node_get(cur); continue; } if (mt76_string_prop_find(country, dev->alpha2) || mt76_string_prop_find(regd, region_name)) { + of_node_put(fallback); of_node_put(np); return cur; } @@ -356,7 +358,7 @@ s8 mt76_get_rate_power_limits(struct mt76_phy *phy, s8 target_power) { struct mt76_dev *dev = phy->dev; - struct device_node *np; + struct device_node *np, *band_np; const s8 *val; char name[16]; u32 mcs_rates = dev->drv->mcs_rates; @@ -389,15 +391,18 @@ s8 mt76_get_rate_power_limits(struct mt76_phy *phy, band = '6'; break; default: + of_node_put(np); return target_power; } snprintf(name, sizeof(name), "txpower-%cg", band); - np = of_get_child_by_name(np, name); - if (!np) + band_np = of_get_child_by_name(np, name); + of_node_put(np); + if (!band_np) return target_power; - np = mt76_find_channel_node(np, chan); + np = mt76_find_channel_node(band_np, chan); + of_node_put(band_np); if (!np) return target_power; @@ -422,6 +427,8 @@ s8 mt76_get_rate_power_limits(struct mt76_phy *phy, ARRAY_SIZE(dest->ru), val, len, target_power, txs_delta, &max_power); + of_node_put(np); + return max_power; } EXPORT_SYMBOL_GPL(mt76_get_rate_power_limits); -- 2.53.0