diff options
| author | Anton Lindqvist <anton@cvs.openbsd.org> | 2021-08-25 05:46:32 +0000 |
|---|---|---|
| committer | Anton Lindqvist <anton@cvs.openbsd.org> | 2021-08-25 05:46:32 +0000 |
| commit | e4d6b6591d7758b6e4e65ed17394b82b5bb2c6a5 (patch) | |
| tree | e5b6c9d4045931b45ec8180f9b400d4ac1f6e3bf /sys/dev | |
| parent | 58ed82de6472515cd4420a639041dd3fa3e62973 (diff) | |
If the buffer given to the ucc interrupt handler is too long, do not
discard it but instead just inspect the first bytes that can make up a
usage. This is a work around as the correct solution is to only inspect
a limited number of bits as given by the report count and size
associated with the Consumer usage page.
Final piece to get florian@'s Microsoft Sculpt keyboard working.
Diffstat (limited to 'sys/dev')
| -rw-r--r-- | sys/dev/usb/ucc.c | 12 |
1 files changed, 10 insertions, 2 deletions
diff --git a/sys/dev/usb/ucc.c b/sys/dev/usb/ucc.c index 6043d707e14..0e1986b83d3 100644 --- a/sys/dev/usb/ucc.c +++ b/sys/dev/usb/ucc.c @@ -1,4 +1,4 @@ -/* $OpenBSD: ucc.c,v 1.7 2021/08/25 05:45:33 anton Exp $ */ +/* $OpenBSD: ucc.c,v 1.8 2021/08/25 05:46:31 anton Exp $ */ /* * Copyright (c) 2021 Anton Lindqvist <anton@openbsd.org> @@ -479,11 +479,19 @@ int ucc_intr_to_usage(u_char *buf, u_int buflen, int32_t *usage) { int32_t x = 0; + int maxlen = sizeof(*usage); int i; - if (buflen == 0 || buflen > sizeof(*usage)) + if (buflen == 0) return 1; + /* + * XXX should only look at the bits given by the report size and report + * count associated with the Consumer usage page. + */ + if (buflen > maxlen) + buflen = maxlen; + for (i = buflen - 1; i >= 0; i--) { x |= buf[i]; if (i > 0) |