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| author | Ignat Korchagin <ignat.korchagin@gmail.com> | 2016-03-17 18:00:29 +0000 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2016-05-04 14:48:50 -0700 |
| commit | 4a1bb501e4b65908b102f0b371b0621ff18ad5c3 (patch) | |
| tree | c6619bd925fcaaa4a6aac6433fca907f4958f65a | |
| parent | 3c6266d57c4c4fa02588070347acf21b610bbd96 (diff) | |
| download | lwn-4a1bb501e4b65908b102f0b371b0621ff18ad5c3.tar.gz lwn-4a1bb501e4b65908b102f0b371b0621ff18ad5c3.zip | |
USB: usbip: fix potential out-of-bounds write
commit b348d7dddb6c4fbfc810b7a0626e8ec9e29f7cbb upstream.
Fix potential out-of-bounds write to urb->transfer_buffer
usbip handles network communication directly in the kernel. When receiving a
packet from its peer, usbip code parses headers according to protocol. As
part of this parsing urb->actual_length is filled. Since the input for
urb->actual_length comes from the network, it should be treated as untrusted.
Any entity controlling the network may put any value in the input and the
preallocated urb->transfer_buffer may not be large enough to hold the data.
Thus, the malicious entity is able to write arbitrary data to kernel memory.
Signed-off-by: Ignat Korchagin <ignat.korchagin@gmail.com>
Cc: Sasha Levin <sasha.levin@oracle.com>
Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
| -rw-r--r-- | drivers/usb/usbip/usbip_common.c | 11 |
1 files changed, 11 insertions, 0 deletions
diff --git a/drivers/usb/usbip/usbip_common.c b/drivers/usb/usbip/usbip_common.c index facaaf003f19..e40da7759a0e 100644 --- a/drivers/usb/usbip/usbip_common.c +++ b/drivers/usb/usbip/usbip_common.c @@ -741,6 +741,17 @@ int usbip_recv_xbuff(struct usbip_device *ud, struct urb *urb) if (!(size > 0)) return 0; + if (size > urb->transfer_buffer_length) { + /* should not happen, probably malicious packet */ + if (ud->side == USBIP_STUB) { + usbip_event_add(ud, SDEV_EVENT_ERROR_TCP); + return 0; + } else { + usbip_event_add(ud, VDEV_EVENT_ERROR_TCP); + return -EPIPE; + } + } + ret = usbip_recv(ud->tcp_socket, urb->transfer_buffer, size); if (ret != size) { dev_err(&urb->dev->dev, "recv xbuf, %d\n", ret); |