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| author | Dmitry Torokhov <dmitry.torokhov@gmail.com> | 2016-06-27 14:12:34 -0700 |
|---|---|---|
| committer | Dmitry Torokhov <dmitry.torokhov@gmail.com> | 2016-07-20 17:50:23 -0700 |
| commit | 510cccb5b0c8868a2b302a0ab524da7912da648b (patch) | |
| tree | 3b56ec2823c7b2757d1dea1c97b3b02a4595f7c4 | |
| parent | e4add7b6beaff4061693d0632bc1dcb306edba10 (diff) | |
tty/vt/keyboard: fix OOB access in do_compute_shiftstate()
The size of individual keymap in drivers/tty/vt/keyboard.c is NR_KEYS,
which is currently 256, whereas number of keys/buttons in input device (and
therefor in key_down) is much larger - KEY_CNT - 768, and that can cause
out-of-bound access when we do
sym = U(key_maps[0][k]);
with large 'k'.
To fix it we should not attempt iterating beyond smaller of NR_KEYS and
KEY_CNT.
Also while at it let's switch to for_each_set_bit() instead of open-coding
it.
Reported-by: Sasha Levin <sasha.levin@oracle.com>
Reviewed-by: Guenter Roeck <linux@roeck-us.net>
Cc: stable@vger.kernel.org
Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>