Module Name: src
Committed By: riastradh
Date: Sun Mar 20 13:13:10 UTC 2022
Modified Files:
src/sys/dev/usb: ualea.c
Log Message:
ualea(4): Simplify xfer error branches.
- Avoid going into a loop in case the transfer fails repeatedly --
just give up immediately if it fails.
- Assert result size is reasonable; no need to assume usbdi(9) is
malicious. If it can return ux_actlen > ux_length, that's a bug in
usbdi(9) that we should fix.
To generate a diff of this commit:
cvs rdiff -u -r1.17 -r1.18 src/sys/dev/usb/ualea.c
Please note that diffs are not public domain; they are subject to the
copyright notices on the relevant files.
Modified files:
Index: src/sys/dev/usb/ualea.c
diff -u src/sys/dev/usb/ualea.c:1.17 src/sys/dev/usb/ualea.c:1.18
--- src/sys/dev/usb/ualea.c:1.17 Sun Mar 20 00:41:01 2022
+++ src/sys/dev/usb/ualea.c Sun Mar 20 13:13:10 2022
@@ -1,4 +1,4 @@
-/* $NetBSD: ualea.c,v 1.17 2022/03/20 00:41:01 riastradh Exp $ */
+/* $NetBSD: ualea.c,v 1.18 2022/03/20 13:13:10 riastradh Exp $ */
/*-
* Copyright (c) 2017 The NetBSD Foundation, Inc.
@@ -30,7 +30,7 @@
*/
#include <sys/cdefs.h>
-__KERNEL_RCSID(0, "$NetBSD: ualea.c,v 1.17 2022/03/20 00:41:01 riastradh Exp $");
+__KERNEL_RCSID(0, "$NetBSD: ualea.c,v 1.18 2022/03/20 13:13:10 riastradh Exp $");
#include <sys/types.h>
#include <sys/atomic.h>
@@ -230,39 +230,37 @@ ualea_xfer_done(struct usbd_xfer *xfer,
void *pkt;
uint32_t pktsize;
- /* Check the transfer status. */
+ /*
+ * If the transfer failed, give up -- forget what we need and
+ * don't reschedule ourselves.
+ */
if (status) {
device_printf(sc->sc_dev, "xfer failed: %s\n",
usbd_errstr(status));
- pktsize = 0;
- goto out;
+ mutex_enter(&sc->sc_lock);
+ sc->sc_needed = 0;
+ sc->sc_inflight = false;
+ mutex_exit(&sc->sc_lock);
+ return;
}
- /* Get and sanity-check the transferred size. */
+ /* Get the transferred size. */
usbd_get_xfer_status(xfer, NULL, &pkt, &pktsize, NULL);
- if (pktsize > sc->sc_maxpktsize) {
- device_printf(sc->sc_dev,
- "bogus packet size: %"PRIu32" > %"PRIu16" (max), ignoring"
- "\n",
- pktsize, sc->sc_maxpktsize);
- goto out;
- }
+ KASSERTMSG(pktsize <= sc->sc_maxpktsize,
+ "pktsize %"PRIu32" > %"PRIu16" (max)",
+ pktsize, sc->sc_maxpktsize);
/* Add the data to the pool. */
rnd_add_data(&sc->sc_rnd, pkt, pktsize, NBBY*pktsize);
-out:
+ /*
+ * Debit what we contributed from what we need, mark the xfer
+ * as done, and reschedule the xfer if we still need more.
+ */
mutex_enter(&sc->sc_lock);
-
- /* Debit what we contributed from what we need. */
sc->sc_needed -= MIN(sc->sc_needed, pktsize);
-
- /* Mark xfer done. */
sc->sc_inflight = false;
-
- /* Reissue xfer if we still need more. */
ualea_xfer(sc);
-
mutex_exit(&sc->sc_lock);
}
