From: Daniel Rosenberg <drosen@google.com>
Date: Fri, 8 Jul 2016 21:15:14 +0000 (-0700)
Subject: ANDROID: sdcardfs: Truncate packages_gid.list on overflow
X-Git-Url: https://git.stricted.de/?a=commitdiff_plain;h=6f499f0ca341ec71dd7eb1858aed0951563f0a82;p=GitHub%2Fmoto-9609%2Fandroid_kernel_motorola_exynos9610.git

ANDROID: sdcardfs: Truncate packages_gid.list on overflow

packages_gid.list was improperly returning the wrong
count. Use scnprintf instead, and inform the user that
the list was truncated if it is.

Bug: 30013843
Change-Id: Ida2b2ef7cd86dd87300bfb4c2cdb6bfe2ee1650d
Signed-off-by: Daniel Rosenberg <drosen@google.com>
---

diff --git a/fs/sdcardfs/packagelist.c b/fs/sdcardfs/packagelist.c
index 10f0d6be718b..9c3340528eee 100644
--- a/fs/sdcardfs/packagelist.c
+++ b/fs/sdcardfs/packagelist.c
@@ -335,13 +335,20 @@ static ssize_t packages_attr_show(struct config_item *item,
 	struct hashtable_entry *hash_cur;
 	struct hlist_node *h_t;
 	int i;
-	int count = 0;
+	int count = 0, written = 0;
+	char errormsg[] = "<truncated>\n";
+
 	mutex_lock(&pkgl_data_all->hashtable_lock);
-	hash_for_each_safe(pkgl_data_all->package_to_appid, i, h_t, hash_cur, hlist)
-		count += snprintf(page + count, PAGE_SIZE - count, "%s %d\n", (char *)hash_cur->key, hash_cur->value);
+	hash_for_each_safe(pkgl_data_all->package_to_appid, i, h_t, hash_cur, hlist) {
+		written = scnprintf(page + count, PAGE_SIZE - sizeof(errormsg) - count, "%s %d\n", (char *)hash_cur->key, hash_cur->value);
+		if (count + written == PAGE_SIZE - sizeof(errormsg)) {
+			count += scnprintf(page + count, PAGE_SIZE - count, errormsg);
+			break;
+		}
+		count += written;
+	}
 	mutex_unlock(&pkgl_data_all->hashtable_lock);
 
-
 	return count;
 }