From: Greg KH on
2.6.27-stable review patch. If anyone has any objections, please let us know.

------------------

From: Andre Osterhues <aosterhues(a)escrypt.com>

commit a6f80fb7b5986fda663d94079d3bba0937a6b6ff upstream.

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 <aosterhues(a)escrypt.com>
Signed-off-by: Tyler Hicks <tyhicks(a)linux.vnet.ibm.com>
Signed-off-by: Linus Torvalds <torvalds(a)linux-foundation.org>
Signed-off-by: Greg Kroah-Hartman <gregkh(a)suse.de>

---
fs/ecryptfs/messaging.c | 17 +++++++++--------
1 file changed, 9 insertions(+), 8 deletions(-)

--- a/fs/ecryptfs/messaging.c
+++ b/fs/ecryptfs/messaging.c
@@ -30,9 +30,9 @@ static struct mutex ecryptfs_msg_ctx_lis

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;
@@ -599,18 +599,19 @@ int ecryptfs_init_messaging(unsigned int
}
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)
@@ -680,7 +681,7 @@ void ecryptfs_release_messaging(unsigned
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,


--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo(a)vger.kernel.org
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/