The previous commit fixed handling of incomplete packets but broke error
handling: offsetof returns an unsigned value (size_t), but when compared
against the signed return value, the return value is interpreted as if
it were unsigned, so negative return values are never less than the
offset.
Fixes: 22d65765f211 ("HID: u2fzero: ignore incomplete packets without data")
Fixes: 42337b9d4d95 ("HID: add driver for U2F Zero built-in LED and RNG")
Signed-off-by: Andrej Shadura <andrew.shadura@xxxxxxxxxxxxxxx>
---
drivers/hid/hid-u2fzero.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/drivers/hid/hid-u2fzero.c b/drivers/hid/hid-u2fzero.c
index d70cd3d7f583..5145d758bea0 100644
--- a/drivers/hid/hid-u2fzero.c
+++ b/drivers/hid/hid-u2fzero.c
@@ -200,7 +200,7 @@ static int u2fzero_rng_read(struct hwrng *rng, void *data,
ret = u2fzero_recv(dev, &req, &resp);
/* ignore errors or packets without data */
- if (ret < offsetof(struct u2f_hid_msg, init.data))
+ if (ret < 0 || ret < offsetof(struct u2f_hid_msg, init.data))
return 0;
/* only take the minimum amount of data it is safe to take */
--
2.33.0
