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author | Benjamin Tissoires <benjamin.tissoires@redhat.com> | 2013-09-11 21:56:57 +0200 |
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committer | Jiri Kosina <jkosina@suse.cz> | 2013-09-13 15:13:22 +0200 |
commit | cc6b54aa54bf40b762cab45a9fc8aa81653146eb (patch) | |
tree | 311d5b5b18d0d59e2cda8b45146c8a6ab3cc5fee /drivers/hid/hid-input.c | |
parent | 0a9cd0a80ac559357c6a90d26c55270ed752aa26 (diff) | |
download | linux-cc6b54aa54bf40b762cab45a9fc8aa81653146eb.tar.gz linux-cc6b54aa54bf40b762cab45a9fc8aa81653146eb.tar.xz |
HID: validate feature and input report details
When dealing with usage_index, be sure to properly use unsigned instead of
int to avoid overflows.
When working on report fields, always validate that their report_counts are
in bounds.
Without this, a HID device could report a malicious feature report that
could trick the driver into a heap overflow:
[ 634.885003] usb 1-1: New USB device found, idVendor=0596, idProduct=0500
...
[ 676.469629] BUG kmalloc-192 (Tainted: G W ): Redzone overwritten
CVE-2013-2897
Cc: stable@vger.kernel.org
Signed-off-by: Benjamin Tissoires <benjamin.tissoires@redhat.com>
Acked-by: Kees Cook <keescook@chromium.org>
Signed-off-by: Jiri Kosina <jkosina@suse.cz>
Diffstat (limited to 'drivers/hid/hid-input.c')
-rw-r--r-- | drivers/hid/hid-input.c | 11 |
1 files changed, 10 insertions, 1 deletions
diff --git a/drivers/hid/hid-input.c b/drivers/hid/hid-input.c index b420f4a0fd28..8741d953dcc8 100644 --- a/drivers/hid/hid-input.c +++ b/drivers/hid/hid-input.c @@ -485,6 +485,10 @@ static void hidinput_configure_usage(struct hid_input *hidinput, struct hid_fiel if (field->flags & HID_MAIN_ITEM_CONSTANT) goto ignore; + /* Ignore if report count is out of bounds. */ + if (field->report_count < 1) + goto ignore; + /* only LED usages are supported in output fields */ if (field->report_type == HID_OUTPUT_REPORT && (usage->hid & HID_USAGE_PAGE) != HID_UP_LED) { @@ -1236,7 +1240,11 @@ static void report_features(struct hid_device *hid) rep_enum = &hid->report_enum[HID_FEATURE_REPORT]; list_for_each_entry(rep, &rep_enum->report_list, list) - for (i = 0; i < rep->maxfield; i++) + for (i = 0; i < rep->maxfield; i++) { + /* Ignore if report count is out of bounds. */ + if (rep->field[i]->report_count < 1) + continue; + for (j = 0; j < rep->field[i]->maxusage; j++) { /* Verify if Battery Strength feature is available */ hidinput_setup_battery(hid, HID_FEATURE_REPORT, rep->field[i]); @@ -1245,6 +1253,7 @@ static void report_features(struct hid_device *hid) drv->feature_mapping(hid, rep->field[i], rep->field[i]->usage + j); } + } } static struct hid_input *hidinput_allocate(struct hid_device *hid) |