mirror of
https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git
synced 2026-09-22 09:34:56 +02:00
Sangho Lee
46ca5ab397
commit47778d2c20upstream. hidp_recv_ctrl_frame() and hidp_recv_intr_frame() read skb->data[0] before checking that the L2CAP SDU contains a transaction header. A connected HIDP peer can send an empty basic-mode SDU and make both paths use an uninitialized byte from skb tailroom. KMSAN reports the use in hidp_session_run(), with the uninitialized value originating in __alloc_skb() through vhci_write(). The control path produces two reports and the interrupt path produces one. The byte can also be controlled by a malformed lower-layer packet. If an HCI ACL packet contains an L2CAP PDU with a declared zero-length payload followed by an extra 0x15 byte, l2cap_recv_acldata() reduces skb->len to the declared PDU length before dispatch. The current HIDP path nevertheless consumes the extra byte as HIDP_TRANS_HID_CONTROL | HIDP_CTRL_VIRTUAL_CABLE_UNPLUG and terminates the HIDP session. With this change, the same packet is discarded and a subsequent feature report request succeeds. Pull the transaction header with skb_pull_data() and discard frames that do not contain it. Fixes:1da177e4c3("Linux-2.6.12-rc2") Cc: stable@vger.kernel.org Signed-off-by: Sangho Lee <kudo3228@gmail.com> Signed-off-by: Luiz Augusto von Dentz <luiz.von.dentz@intel.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Linux kernel
============
There are several guides for kernel developers and users. These guides can
be rendered in a number of formats, like HTML and PDF. Please read
Documentation/admin-guide/README.rst first.
In order to build the documentation, use ``make htmldocs`` or
``make pdfdocs``. The formatted documentation can also be read online at:
https://www.kernel.org/doc/html/latest/
There are various text files in the Documentation/ subdirectory,
several of them using the Restructured Text markup notation.
Please read the Documentation/process/changes.rst file, as it contains the
requirements for building and running the kernel, and information about
the problems which may result by upgrading your kernel.