From 3ddfe3bdd3cf199676737fbd8cb7878b962acd2a Mon Sep 17 00:00:00 2001 From: Zong-Zhe Yang Date: Fri, 2 Dec 2022 14:05:20 +0800 Subject: wifi: rtw89: don't request partial firmware if SECURITY_LOADPIN_ENFORCE Kernel logs on platform enabling SECURITY_LOADPIN_ENFORCE ------ ``` LoadPin: firmware old-api-denied obj= pid=810 cmdline="modprobe -q -- rtw89_8852ce" rtw89_8852ce 0000:01:00.0: loading /lib/firmware/rtw89/rtw8852c_fw.bin failed with error -1 rtw89_8852ce 0000:01:00.0: Direct firmware load for rtw89/rtw8852c_fw.bin failed with error -1 rtw89_8852ce 0000:01:00.0: failed to early request firmware: -1 ``` Trace ------ ``` request_partial_firmware_into_buf() > _request_firmware() >> fw_get_filesystem_firmware() >>> kernel_read_file_from_path_initns() >>>> kernel_read_file() >>>>> security_kernel_read_file() // It will iterate enabled LSMs' hooks for kernel_read_file. // With loadpin, it hooks loadpin_read_file. ``` If SECURITY_LOADPIN_ENFORCE is enabled, doing kernel_read_file() on partial files will be denied and return -EPERM (-1). Then, the outer API based on it, e.g. request_partial_firmware_into_buf(), will get the error. In the case, we cannot get the firmware stuffs right, even though there might be no error other than a permission issue on reading a partial file. So we have to request full firmware if SECURITY_LOADPIN_ENFORCE is enabled. It makes us still have a chance to do early firmware work on this kind of platforms. Signed-off-by: Zong-Zhe Yang Signed-off-by: Ping-Ke Shih Signed-off-by: Kalle Valo Link: https://lore.kernel.org/r/20221202060521.501512-2-pkshih@realtek.com --- drivers/net/wireless/realtek/rtw89/fw.c | 30 +++++++++++++++++++++--------- drivers/net/wireless/realtek/rtw89/fw.h | 15 +++++++++++++++ 2 files changed, 36 insertions(+), 9 deletions(-) (limited to 'drivers/net/wireless') diff --git a/drivers/net/wireless/realtek/rtw89/fw.c b/drivers/net/wireless/realtek/rtw89/fw.c index 7e682709232d..f5daea0d4f93 100644 --- a/drivers/net/wireless/realtek/rtw89/fw.c +++ b/drivers/net/wireless/realtek/rtw89/fw.c @@ -277,25 +277,37 @@ void rtw89_early_fw_feature_recognize(struct device *device, const struct rtw89_chip_info *chip, u32 *early_feat_map) { - union { - struct rtw89_mfw_hdr mfw_hdr; - u8 fw_hdr[RTW89_FW_HDR_SIZE]; - } buf = {}; + union rtw89_compat_fw_hdr buf = {}; const struct firmware *firmware; + bool full_req = false; u32 ver_code; int ret; int i; - ret = request_partial_firmware_into_buf(&firmware, chip->fw_name, - device, &buf, sizeof(buf), 0); + /* If SECURITY_LOADPIN_ENFORCE is enabled, reading partial files will + * be denied (-EPERM). Then, we don't get right firmware things as + * expected. So, in this case, we have to request full firmware here. + */ + if (IS_ENABLED(CONFIG_SECURITY_LOADPIN_ENFORCE)) + full_req = true; + + if (full_req) + ret = request_firmware(&firmware, chip->fw_name, device); + else + ret = request_partial_firmware_into_buf(&firmware, chip->fw_name, + device, &buf, sizeof(buf), + 0); + if (ret) { dev_err(device, "failed to early request firmware: %d\n", ret); return; } - ver_code = buf.mfw_hdr.sig != RTW89_MFW_SIG ? - RTW89_FW_HDR_VER_CODE(&buf.fw_hdr) : - RTW89_MFW_HDR_VER_CODE(&buf.mfw_hdr); + if (full_req) + ver_code = rtw89_compat_fw_hdr_ver_code(firmware->data); + else + ver_code = rtw89_compat_fw_hdr_ver_code(&buf); + if (!ver_code) goto out; diff --git a/drivers/net/wireless/realtek/rtw89/fw.h b/drivers/net/wireless/realtek/rtw89/fw.h index 46d57414f24e..5c4c7de1b4f5 100644 --- a/drivers/net/wireless/realtek/rtw89/fw.h +++ b/drivers/net/wireless/realtek/rtw89/fw.h @@ -3291,6 +3291,21 @@ struct fwcmd_hdr { __le32 hdr1; }; +union rtw89_compat_fw_hdr { + struct rtw89_mfw_hdr mfw_hdr; + u8 fw_hdr[RTW89_FW_HDR_SIZE]; +}; + +static inline u32 rtw89_compat_fw_hdr_ver_code(const void *fw_buf) +{ + const union rtw89_compat_fw_hdr *compat = (typeof(compat))fw_buf; + + if (compat->mfw_hdr.sig == RTW89_MFW_SIG) + return RTW89_MFW_HDR_VER_CODE(&compat->mfw_hdr); + else + return RTW89_FW_HDR_VER_CODE(&compat->fw_hdr); +} + #define RTW89_H2C_RF_PAGE_SIZE 500 #define RTW89_H2C_RF_PAGE_NUM 3 struct rtw89_fw_h2c_rf_reg_info { -- cgit v1.2.3