Module Name: src
Committed By: riastradh
Date: Tue Sep 13 09:47:17 UTC 2022
Modified Files:
src/sys/dev/usb: usbdi.c
Log Message:
usbdi(9): Rule out possible race to read xfer->ux_status.
I think this might actually be safe, because when it's synchronous,
the xfer can't be reused except by the caller after usbd_transfer
returns. But let's make it definitely not wrong instead of maybe
actually safe.
To generate a diff of this commit:
cvs rdiff -u -r1.244 -r1.245 src/sys/dev/usb/usbdi.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/usbdi.c
diff -u src/sys/dev/usb/usbdi.c:1.244 src/sys/dev/usb/usbdi.c:1.245
--- src/sys/dev/usb/usbdi.c:1.244 Wed Sep 7 10:41:34 2022
+++ src/sys/dev/usb/usbdi.c Tue Sep 13 09:47:17 2022
@@ -1,4 +1,4 @@
-/* $NetBSD: usbdi.c,v 1.244 2022/09/07 10:41:34 riastradh Exp $ */
+/* $NetBSD: usbdi.c,v 1.245 2022/09/13 09:47:17 riastradh Exp $ */
/*
* Copyright (c) 1998, 2012, 2015 The NetBSD Foundation, Inc.
@@ -32,7 +32,7 @@
*/
#include <sys/cdefs.h>
-__KERNEL_RCSID(0, "$NetBSD: usbdi.c,v 1.244 2022/09/07 10:41:34 riastradh Exp $");
+__KERNEL_RCSID(0, "$NetBSD: usbdi.c,v 1.245 2022/09/13 09:47:17 riastradh Exp $");
#ifdef _KERNEL_OPT
#include "opt_usb.h"
@@ -501,10 +501,10 @@ usbd_transfer(struct usbd_xfer *xfer)
break;
}
}
- SDT_PROBE2(usb, device, xfer, done, xfer, xfer->ux_status);
- /* XXX Race to read xfer->ux_status? */
+ err = xfer->ux_status;
+ SDT_PROBE2(usb, device, xfer, done, xfer, err);
usbd_unlock_pipe(pipe);
- return xfer->ux_status;
+ return err;
}
/* Like usbd_transfer(), but waits for completion. */
