On 6/14/23 08:10, Azeem Shaikh wrote:
strlcpy() reads the entire source buffer first.
This read may exceed the destination size limit.
This is both inefficient and can lead to linear read
overflows if a source string is not NUL-terminated [1].
In an effort to remove strlcpy() completely [2], replace
strlcpy() here with strscpy().
Direct replacement is safe here since return value of -errno
is used to check for truncation instead of sizeof(dest).
[1] https://www.kernel.org/doc/html/latest/process/deprecated.html#strlcpy
[2] https://github.com/KSPP/linux/issues/89
Signed-off-by: Azeem Shaikh <azeemshaikh38@xxxxxxxxx>
---
v1: https://lore.kernel.org/all/20230613004402.3540432-1-azeemshaikh38@xxxxxxxxx/
Changes from v1 - uses "< 0" instead of "== -E2BIG".
drivers/usb/usbip/stub_main.c | 3 +--
1 file changed, 1 insertion(+), 2 deletions(-)
diff --git a/drivers/usb/usbip/stub_main.c b/drivers/usb/usbip/stub_main.c
index e8c3131a8543..97043b4df275 100644
--- a/drivers/usb/usbip/stub_main.c
+++ b/drivers/usb/usbip/stub_main.c
@@ -174,8 +174,7 @@ static ssize_t match_busid_store(struct device_driver *dev, const char *buf,
return -EINVAL;
/* busid needs to include \0 termination */
- len = strlcpy(busid, buf + 4, BUSID_SIZE);
- if (sizeof(busid) <= len)
+ if (strscpy(busid, buf + 4, BUSID_SIZE) < 0)
return -EINVAL;
if (!strncmp(buf, "add ", 4)) {
Than you Kees for the review.
If Kees is happy, I am happy :)
Acked-by: Shuah Khan <skhan@xxxxxxxxxxxxxxxxxxx>
thanks,
-- Shuah
