diff options
author | Kees Cook <keescook@chromium.org> | 2013-08-28 22:29:55 +0200 |
---|---|---|
committer | Jiri Kosina <jkosina@suse.cz> | 2013-08-29 11:01:25 +0200 |
commit | 43622021d2e2b82ea03d883926605bdd0525e1d1 (patch) | |
tree | eb347fb9b63e544151787d58f8940bdd957961a0 /drivers/hid | |
parent | 58c59bc997d86593f0bea41845885917cf304d22 (diff) |
HID: validate HID report id size
The "Report ID" field of a HID report is used to build indexes of
reports. The kernel's index of these is limited to 256 entries, so any
malicious device that sets a Report ID greater than 255 will trigger
memory corruption on the host:
[ 1347.156239] BUG: unable to handle kernel paging request at ffff88094958a878
[ 1347.156261] IP: [<ffffffff813e4da0>] hid_register_report+0x2a/0x8b
CVE-2013-2888
Signed-off-by: Kees Cook <keescook@chromium.org>
Cc: stable@kernel.org
Signed-off-by: Jiri Kosina <jkosina@suse.cz>
Diffstat (limited to 'drivers/hid')
-rw-r--r-- | drivers/hid/hid-core.c | 10 |
1 files changed, 7 insertions, 3 deletions
diff --git a/drivers/hid/hid-core.c b/drivers/hid/hid-core.c index 36668d1aca8..5ea7d51e45b 100644 --- a/drivers/hid/hid-core.c +++ b/drivers/hid/hid-core.c @@ -63,6 +63,8 @@ struct hid_report *hid_register_report(struct hid_device *device, unsigned type, struct hid_report_enum *report_enum = device->report_enum + type; struct hid_report *report; + if (id >= HID_MAX_IDS) + return NULL; if (report_enum->report_id_hash[id]) return report_enum->report_id_hash[id]; @@ -404,8 +406,10 @@ static int hid_parser_global(struct hid_parser *parser, struct hid_item *item) case HID_GLOBAL_ITEM_TAG_REPORT_ID: parser->global.report_id = item_udata(item); - if (parser->global.report_id == 0) { - hid_err(parser->device, "report_id 0 is invalid\n"); + if (parser->global.report_id == 0 || + parser->global.report_id >= HID_MAX_IDS) { + hid_err(parser->device, "report_id %u is invalid\n", + parser->global.report_id); return -1; } return 0; @@ -575,7 +579,7 @@ static void hid_close_report(struct hid_device *device) for (i = 0; i < HID_REPORT_TYPES; i++) { struct hid_report_enum *report_enum = device->report_enum + i; - for (j = 0; j < 256; j++) { + for (j = 0; j < HID_MAX_IDS; j++) { struct hid_report *report = report_enum->report_id_hash[j]; if (report) hid_free_report(report); |