[PATCH v3] HID: ft260: improve error handling of ft260_hid_feature_report_get()
From: Michael Zaidman <michael.zaidman@gmail.com>
Date: 2021-05-11 10:06:55
Also in:
linux-i2c, lkml
Subsystem:
ft260 ftdi usb-hid to i2c bridge driver, hid core layer, the rest · Maintainers:
Michael Zaidman, Jiri Kosina, Benjamin Tissoires, Linus Torvalds
Fixes: 6a82582d9fa4 ("HID: ft260: add usb hid to i2c host bridge driver")
The ft260_hid_feature_report_get() checks if the return size matches
the requested size. But the function can also fail with at least -ENOMEM.
Add the < 0 checks.
In ft260_hid_feature_report_get(), do not do the memcpy to the caller's
buffer if there is an error.
Fixes: 6a82582d9fa4 ("HID: ft260: add usb hid to i2c host bridge driver")
Signed-off-by: Tom Rix <trix@redhat.com>
---
v3 Simplify and optimize the changes
---
v2: add unlikely()'s for error conditions
---
Signed-off-by: Tom Rix <trix@redhat.com>
Signed-off-by: Michael Zaidman <michael.zaidman@gmail.com>
---
drivers/hid/hid-ft260.c | 24 ++++++++++++------------
1 file changed, 12 insertions(+), 12 deletions(-)
diff --git a/drivers/hid/hid-ft260.c b/drivers/hid/hid-ft260.c
index 047aa85a7c83..7f4cb823129e 100644
--- a/drivers/hid/hid-ft260.c
+++ b/drivers/hid/hid-ft260.c@@ -249,7 +249,10 @@ static int ft260_hid_feature_report_get(struct hid_device *hdev, ret = hid_hw_raw_request(hdev, report_id, buf, len, HID_FEATURE_REPORT, HID_REQ_GET_REPORT); - memcpy(data, buf, len); + if (likely(ret == len)) + memcpy(data, buf, len); + else if (ret >= 0) + ret = -EIO; kfree(buf); return ret; }
@@ -298,7 +301,7 @@ static int ft260_xfer_status(struct ft260_device *dev) ret = ft260_hid_feature_report_get(hdev, FT260_I2C_STATUS, (u8 *)&report, sizeof(report)); - if (ret < 0) { + if (unlikely(ret < 0)) { hid_err(hdev, "failed to retrieve status: %d\n", ret); return ret; }
@@ -720,10 +723,9 @@ static int ft260_get_system_config(struct hid_device *hdev, ret = ft260_hid_feature_report_get(hdev, FT260_SYSTEM_SETTINGS, (u8 *)cfg, len); - if (ret != len) { + if (ret < 0) { hid_err(hdev, "failed to retrieve system status\n"); - if (ret >= 0) - return -EIO; + return ret; } return 0; }
@@ -776,8 +778,8 @@ static int ft260_byte_show(struct hid_device *hdev, int id, u8 *cfg, int len, int ret; ret = ft260_hid_feature_report_get(hdev, id, cfg, len); - if (ret != len && ret >= 0) - return -EIO; + if (ret < 0) + return ret; return scnprintf(buf, PAGE_SIZE, "%hi\n", *field); }
@@ -788,8 +790,8 @@ static int ft260_word_show(struct hid_device *hdev, int id, u8 *cfg, int len, int ret; ret = ft260_hid_feature_report_get(hdev, id, cfg, len); - if (ret != len && ret >= 0) - return -EIO; + if (ret < 0) + return ret; return scnprintf(buf, PAGE_SIZE, "%hi\n", le16_to_cpu(*field)); }
@@ -940,10 +942,8 @@ static int ft260_probe(struct hid_device *hdev, const struct hid_device_id *id) ret = ft260_hid_feature_report_get(hdev, FT260_CHIP_VERSION, (u8 *)&version, sizeof(version)); - if (ret != sizeof(version)) { + if (ret < 0) { hid_err(hdev, "failed to retrieve chip version\n"); - if (ret >= 0) - ret = -EIO; goto err_hid_close; }
--
2.25.1