On Mon, Feb 14, 2022 at 12:32:42PM +0100, Jann Horn wrote:
commit 57bc3d3ae8c14df3ceb4e17d26ddf9eeab304581 upstream.
ax88179_rx_fixup() contains several out-of-bounds accesses that can be triggered by a malicious (or defective) USB device, in particular:
- The metadata array (hdr_off..hdr_off+2*pkt_cnt) can be out of bounds, causing OOB reads and (on big-endian systems) OOB endianness flips.
- A packet can overlap the metadata array, causing a later OOB endianness flip to corrupt data used by a cloned SKB that has already been handed off into the network stack.
- A packet SKB can be constructed whose tail is far beyond its end, causing out-of-bounds heap data to be considered part of the SKB's data.
I have tested that this can be used by a malicious USB device to send a bogus ICMPv6 Echo Request and receive an ICMPv6 Echo Reply in response that contains random kernel heap data. It's probably also possible to get OOB writes from this on a little-endian system somehow - maybe by triggering skb_cow() via IP options processing -, but I haven't tested that.
Fixes: e2ca90c276e1 ("ax88179_178a: ASIX AX88179_178A USB 3.0/2.0 to gigabit ethernet adapter driver") Cc: stable@kernel.org Signed-off-by: Jann Horn jannh@google.com
drivers/net/usb/ax88179_178a.c | 68 +++++++++++++++++++--------------- 1 file changed, 39 insertions(+), 29 deletions(-)
Now queued up, thanks.
greg k-h