3.8.13.10 -stable review patch. If anyone has any objections, please let me know. ------------------ From: Kees Cook <keescook@xxxxxxxxxxxx> commit 43622021d2e2b82ea03d883926605bdd0525e1d1 upstream. 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@xxxxxxxxxxxx> Signed-off-by: Jiri Kosina <jkosina@xxxxxxx> Signed-off-by: Kamal Mostafa <kamal@xxxxxxxxxxxxx> --- drivers/hid/hid-core.c | 10 +++++++--- include/linux/hid.h | 4 +++- 2 files changed, 10 insertions(+), 4 deletions(-) diff --git a/drivers/hid/hid-core.c b/drivers/hid/hid-core.c index 08eb32a..194597f 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); diff --git a/include/linux/hid.h b/include/linux/hid.h index 7330a0f..13d812b 100644 --- a/include/linux/hid.h +++ b/include/linux/hid.h @@ -392,10 +392,12 @@ struct hid_report { struct hid_device *device; /* associated device */ }; +#define HID_MAX_IDS 256 + struct hid_report_enum { unsigned numbered; struct list_head report_list; - struct hid_report *report_id_hash[256]; + struct hid_report *report_id_hash[HID_MAX_IDS]; }; #define HID_REPORT_TYPES 3 -- 1.8.1.2 -- To unsubscribe from this list: send the line "unsubscribe stable" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html