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| author | Dmitry Torokhov <dmitry.torokhov@gmail.com> | 2019-12-08 00:05:18 +0300 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2020-01-14 22:05:44 +0300 |
| commit | cb0a3edf8d00740303e5b42e9c0e72d924fc23d2 (patch) | |
| tree | b4d66fb1a1964e22510070a049d7da0aadf460a0 /drivers/hid/hid-input.c | |
| parent | 912cb3eac58deadf051138c2021cbb3b0acb14b4 (diff) | |
| download | linux-cb0a3edf8d00740303e5b42e9c0e72d924fc23d2.tar.xz | |
HID: hid-input: clear unmapped usages
commit 4f3882177240a1f55e45a3d241d3121341bead78 upstream.
We should not be leaving half-mapped usages with potentially invalid
keycodes, as that may confuse hidinput_find_key() when the key is located
by index, which may end up feeding way too large keycode into the VT
keyboard handler and cause OOB write there:
BUG: KASAN: global-out-of-bounds in clear_bit include/asm-generic/bitops-instrumented.h:56 [inline]
BUG: KASAN: global-out-of-bounds in kbd_keycode drivers/tty/vt/keyboard.c:1411 [inline]
BUG: KASAN: global-out-of-bounds in kbd_event+0xe6b/0x3790 drivers/tty/vt/keyboard.c:1495
Write of size 8 at addr ffffffff89a1b2d8 by task syz-executor108/1722
...
kbd_keycode drivers/tty/vt/keyboard.c:1411 [inline]
kbd_event+0xe6b/0x3790 drivers/tty/vt/keyboard.c:1495
input_to_handler+0x3b6/0x4c0 drivers/input/input.c:118
input_pass_values.part.0+0x2e3/0x720 drivers/input/input.c:145
input_pass_values drivers/input/input.c:949 [inline]
input_set_keycode+0x290/0x320 drivers/input/input.c:954
evdev_handle_set_keycode_v2+0xc4/0x120 drivers/input/evdev.c:882
evdev_do_ioctl drivers/input/evdev.c:1150 [inline]
Cc: stable@vger.kernel.org
Reported-by: syzbot+19340dff067c2d3835c0@syzkaller.appspotmail.com
Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>
Tested-by: Benjamin Tissoires <benjamin.tissoires@redhat.com>
Signed-off-by: Jiri Kosina <jkosina@suse.cz>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Diffstat (limited to 'drivers/hid/hid-input.c')
| -rw-r--r-- | drivers/hid/hid-input.c | 16 |
1 files changed, 12 insertions, 4 deletions
diff --git a/drivers/hid/hid-input.c b/drivers/hid/hid-input.c index 9d24fb0715ba..14e4003fde4d 100644 --- a/drivers/hid/hid-input.c +++ b/drivers/hid/hid-input.c @@ -1116,9 +1116,15 @@ static void hidinput_configure_usage(struct hid_input *hidinput, struct hid_fiel } mapped: - if (device->driver->input_mapped && device->driver->input_mapped(device, - hidinput, field, usage, &bit, &max) < 0) - goto ignore; + if (device->driver->input_mapped && + device->driver->input_mapped(device, hidinput, field, usage, + &bit, &max) < 0) { + /* + * The driver indicated that no further generic handling + * of the usage is desired. + */ + return; + } set_bit(usage->type, input->evbit); @@ -1176,9 +1182,11 @@ mapped: set_bit(MSC_SCAN, input->mscbit); } -ignore: return; +ignore: + usage->type = 0; + usage->code = 0; } void hidinput_hid_event(struct hid_device *hid, struct hid_field *field, struct hid_usage *usage, __s32 value) |