From: Andre Osterhues Date: Tue, 13 Jul 2010 20:59:17 +0000 (-0500) Subject: ecryptfs: Bugfix for error related to ecryptfs_hash_buckets X-Git-Tag: firefly_0821_release~9833^2~1343 X-Git-Url: http://demsky.eecs.uci.edu/git/?a=commitdiff_plain;h=a6f80fb7b5986fda663d94079d3bba0937a6b6ff;p=firefly-linux-kernel-4.4.55.git ecryptfs: Bugfix for error related to ecryptfs_hash_buckets The function ecryptfs_uid_hash wrongly assumes that the second parameter to hash_long() is the number of hash buckets instead of the number of hash bits. This patch fixes that and renames the variable ecryptfs_hash_buckets to ecryptfs_hash_bits to make it clearer. Fixes: CVE-2010-2492 Signed-off-by: Andre Osterhues Signed-off-by: Tyler Hicks Signed-off-by: Linus Torvalds --- diff --git a/fs/ecryptfs/messaging.c b/fs/ecryptfs/messaging.c index 2d8dbce9d485..46c4dd8dfcc3 100644 --- a/fs/ecryptfs/messaging.c +++ b/fs/ecryptfs/messaging.c @@ -31,9 +31,9 @@ static struct mutex ecryptfs_msg_ctx_lists_mux; static struct hlist_head *ecryptfs_daemon_hash; struct mutex ecryptfs_daemon_hash_mux; -static int ecryptfs_hash_buckets; +static int ecryptfs_hash_bits; #define ecryptfs_uid_hash(uid) \ - hash_long((unsigned long)uid, ecryptfs_hash_buckets) + hash_long((unsigned long)uid, ecryptfs_hash_bits) static u32 ecryptfs_msg_counter; static struct ecryptfs_msg_ctx *ecryptfs_msg_ctx_arr; @@ -486,18 +486,19 @@ int ecryptfs_init_messaging(void) } mutex_init(&ecryptfs_daemon_hash_mux); mutex_lock(&ecryptfs_daemon_hash_mux); - ecryptfs_hash_buckets = 1; - while (ecryptfs_number_of_users >> ecryptfs_hash_buckets) - ecryptfs_hash_buckets++; + ecryptfs_hash_bits = 1; + while (ecryptfs_number_of_users >> ecryptfs_hash_bits) + ecryptfs_hash_bits++; ecryptfs_daemon_hash = kmalloc((sizeof(struct hlist_head) - * ecryptfs_hash_buckets), GFP_KERNEL); + * (1 << ecryptfs_hash_bits)), + GFP_KERNEL); if (!ecryptfs_daemon_hash) { rc = -ENOMEM; printk(KERN_ERR "%s: Failed to allocate memory\n", __func__); mutex_unlock(&ecryptfs_daemon_hash_mux); goto out; } - for (i = 0; i < ecryptfs_hash_buckets; i++) + for (i = 0; i < (1 << ecryptfs_hash_bits); i++) INIT_HLIST_HEAD(&ecryptfs_daemon_hash[i]); mutex_unlock(&ecryptfs_daemon_hash_mux); ecryptfs_msg_ctx_arr = kmalloc((sizeof(struct ecryptfs_msg_ctx) @@ -554,7 +555,7 @@ void ecryptfs_release_messaging(void) int i; mutex_lock(&ecryptfs_daemon_hash_mux); - for (i = 0; i < ecryptfs_hash_buckets; i++) { + for (i = 0; i < (1 << ecryptfs_hash_bits); i++) { int rc; hlist_for_each_entry(daemon, elem,