i8254: fix out-of-bounds memory access in pit_ioport_read()
commitd4862a87e31a51de9eb260f25c9e99a75efe3235
authorPetr Matousek <pmatouse@redhat.com>
Wed, 17 Jun 2015 10:46:11 +0000 (17 12:46 +0200)
committerPaolo Bonzini <pbonzini@redhat.com>
Wed, 17 Jun 2015 14:03:47 +0000 (17 16:03 +0200)
tree94c601e5faf63509c6d9f43f98db955566d9033b
parent9dacf32d2cbd66cbcce7944ebdfd6b2df20e33b8
i8254: fix out-of-bounds memory access in pit_ioport_read()

Due converting PIO to the new memory read/write api we no longer provide
separate I/O region lenghts for read and write operations. As a result,
reading from PIT Mode/Command register will end with accessing
pit->channels with invalid index.

Fix this by ignoring read from the Mode/Command register.

This is CVE-2015-3214.

Reported-by: Matt Tait <matttait@google.com>
Fixes: 0505bcdec8228d8de39ab1a02644e71999e7c052
Cc: qemu-stable@nongnu.org
Signed-off-by: Petr Matousek <pmatouse@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
hw/timer/i8254.c