From 9deaedbfc595317976bc93c5486f87e3b45c6d53 Mon Sep 17 00:00:00 2001
From: Peter Hutterer <peter.hutterer@who-t.net>
Date: Thu, 3 Sep 2015 16:17:11 +1000
Subject: [PATCH] Add some device sanity checking

Don't allow devices with zero profiles, zero resolutions, etc.

Signed-off-by: Peter Hutterer <peter.hutterer@who-t.net>
---
 src/libratbag.c | 88 +++++++++++++++++++++++++++++++++++++++++++++++--
 1 file changed, 85 insertions(+), 3 deletions(-)

diff --git a/src/libratbag.c b/src/libratbag.c
index 28398b73..3b2729ff 100644
--- a/src/libratbag.c
+++ b/src/libratbag.c
@@ -297,6 +297,83 @@ ratbag_device_destroy(struct ratbag_device *device)
 	free(device);
 }
 
+static inline bool
+ratbag_sanity_check_device(struct ratbag_device *device)
+{
+	struct ratbag *ratbag = device->ratbag;
+	struct ratbag_profile *profile = NULL;
+	struct ratbag_resolution *res = NULL;
+	bool has_active = false;
+	bool has_default = false;
+	unsigned int nres, nprofiles;
+	bool rc = false;
+	unsigned int i;
+
+	/* arbitrary number: max 16 profiles, does any mouse have more? but
+	 * since we have num_profiles unsigned, it also checks for
+	 * accidental negative */
+	if (device->num_profiles == 0 || device->num_profiles > 16) {
+		log_bug_libratbag(ratbag,
+				  "%s: invalid number of profiles %d\n",
+				  device->name,
+				  device->num_profiles);
+		goto out;
+	}
+
+	nprofiles = ratbag_device_get_num_profiles(device);
+	for (i = 0; i < nprofiles; i++) {
+		profile = ratbag_device_get_profile_by_index(device, i);
+		/* Allow max 1 default profile */
+		if (profile->is_default) {
+			if (has_default) {
+				log_bug_libratbag(ratbag,
+						  "%s: multiple default profiles\n",
+						  device->name);
+				goto out;
+			}
+			has_default = true;
+		}
+
+		/* Allow max 1 active profile */
+		if (profile->is_active) {
+			if (has_active) {
+				log_bug_libratbag(ratbag,
+						  "%s: multiple active profiles\n",
+						  device->name);
+				goto out;
+			}
+			has_active = true;
+		}
+
+		nres = ratbag_profile_get_num_resolutions(profile);
+		if (nres == 0 || nres > 16) {
+				log_bug_libratbag(ratbag,
+						  "%s: minimum 1 resolution required\n",
+						  device->name);
+				goto out;
+		}
+
+		ratbag_profile_unref(profile);
+		profile = NULL;
+	}
+
+	/* Require 1 active profile */
+	if (!has_active) {
+		log_bug_libratbag(ratbag,
+				  "%s: no active profile found\n",
+				  device->name);
+		goto out;
+	}
+
+	rc = true;
+
+out:
+	ratbag_profile_unref(profile);
+	ratbag_resolution_unref(res);
+
+	return rc;
+}
+
 static inline bool
 ratbag_match_id(const struct input_id *dev_id, const struct input_id *match_id)
 {
@@ -326,9 +403,14 @@ ratbag_find_driver(struct ratbag_device *device, const struct input_id *dev_id)
 				device->driver = driver;
 				rc = driver->probe(device, matched_id);
 				if (rc == 0) {
-					log_debug(ratbag, "driver match found\n");
-					device->svg_name = matching_id->svg_filename;
-					return driver;
+					if (!ratbag_sanity_check_device(device)) {
+						driver->remove(device);
+						return NULL;
+					} else {
+						log_debug(ratbag, "driver match found\n");
+						device->svg_name = matching_id->svg_filename;
+						return driver;
+					}
 				}
 
 				device->driver = NULL;