diff options
| author | hselasky <hselasky@FreeBSD.org> | 2015-08-29 06:11:50 +0000 |
|---|---|---|
| committer | hselasky <hselasky@FreeBSD.org> | 2015-08-29 06:11:50 +0000 |
| commit | 6323991c32b50145b2410f193aa0685e74466053 (patch) | |
| tree | b7513c6af1748f611077171dd75c2e98f5d02b87 /sys/dev/usb/usb_pf.c | |
| parent | 10823346a0096906e1c338f89ef960c36b5eae01 (diff) | |
| download | FreeBSD-src-6323991c32b50145b2410f193aa0685e74466053.zip FreeBSD-src-6323991c32b50145b2410f193aa0685e74466053.tar.gz | |
MFC r286799:
Fix race in USB PF which can happen if we stop tracing exactly when
the kernel is tapping an USB transfer. This leads to a NULL pointer
access. The solution is to only trace while the USB bus lock is
locked.
Diffstat (limited to 'sys/dev/usb/usb_pf.c')
| -rw-r--r-- | sys/dev/usb/usb_pf.c | 6 |
1 files changed, 6 insertions, 0 deletions
diff --git a/sys/dev/usb/usb_pf.c b/sys/dev/usb/usb_pf.c index 27ab5f7..8c47e79 100644 --- a/sys/dev/usb/usb_pf.c +++ b/sys/dev/usb/usb_pf.c @@ -220,7 +220,13 @@ usbpf_clone_destroy(struct if_clone *ifc, struct ifnet *ifp) ubus = ifp->if_softc; unit = ifp->if_dunit; + /* + * Lock USB before clearing the "ifp" pointer, to avoid + * clearing the pointer in the middle of a TAP operation: + */ + USB_BUS_LOCK(ubus); ubus->ifp = NULL; + USB_BUS_UNLOCK(ubus); bpfdetach(ifp); if_detach(ifp); if_free(ifp); |
