[PATCH] wifi: rtw89: debug: Fix memory leak in __print_txpwr_map()

[Zilin Guan]

In __print_txpwr_map(), memory is allocated to bufp via vzalloc().
If max_valid_addr is 0, the function returns -EOPNOTSUPP immediately
without freeing bufp, leading to a memory leak.

Fix this by freeing the temporary buffer bufp in the error path.

Compile tested only. Issue found using a prototype static analysis tool
and code review.

Fixes: 036042e15770 ("wifi: rtw89: debug: txpwr table supports Wi-Fi 7 chips")
Signed-off-by: Zilin Guan <zilin@xxxxxxxxxx>
---
 drivers/net/wireless/realtek/rtw89/debug.c | 4 +++-
 1 file changed, 3 insertions(+), 1 deletion(-)

diff --git a/drivers/net/wireless/realtek/rtw89/debug.c b/drivers/net/wireless/realtek/rtw89/debug.c
index 1264c2f82600..c7bd1d0212b6 100644
--- a/drivers/net/wireless/realtek/rtw89/debug.c
+++ b/drivers/net/wireless/realtek/rtw89/debug.c
@@ -834,8 +834,10 @@ static ssize_t __print_txpwr_map(struct rtw89_dev *rtwdev, char *buf, size_t buf
 	else
 		max_valid_addr = map->addr_to;
 
-	if (max_valid_addr == 0)
+	if (max_valid_addr == 0) {
+		vfree(bufp);
 		return -EOPNOTSUPP;
+	}
 
 	for (addr = map->addr_from; addr <= max_valid_addr; addr += 4) {
 		ret = rtw89_mac_txpwr_read32(rtwdev, RTW89_PHY_0, addr, &val);
-- 
2.34.1