eCryptfs: parse_tag_3_packet check tag 3 packet encrypted key size (CVE-2009-2407)

eCryptfs: parse_tag_3_packet check tag 3 packet encrypted key size (CVE-2009-2407)

commit f151cd2c54ddc7714e2f740681350476cda03a28 upstream.

The parse_tag_3_packet function does not check if the tag 3 packet contains a
encrypted key size larger than ECRYPTFS_MAX_ENCRYPTED_KEY_BYTES.

Signed-off-by: Ramon de Carvalho Valle <ramon@risesecurity.org>
[tyhicks@linux.vnet.ibm.com: Added printk newline and changed goto to out_free]
Signed-off-by: Tyler Hicks <tyhicks@linux.vnet.ibm.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>