From patchwork Mon Nov 26 16:55:00 2012 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit Subject: [010/270] eCryptfs: check for eCryptfs cipher support at mount Date: Mon, 26 Nov 2012 06:55:00 -0000 From: Herton Ronaldo Krzesinski X-Patchwork-Id: 201743 Message-Id: <1353949160-26803-11-git-send-email-herton.krzesinski@canonical.com> To: linux-kernel@vger.kernel.org, stable@vger.kernel.org, kernel-team@lists.ubuntu.com Cc: Tim Sally 3.5.7u1 -stable review patch. If anyone has any objections, please let me know. ------------------ From: Tim Sally commit 5f5b331d5c21228a6519dcb793fc1629646c51a6 upstream. The issue occurs when eCryptfs is mounted with a cipher supported by the crypto subsystem but not by eCryptfs. The mount succeeds and an error does not occur until a write. This change checks for eCryptfs cipher support at mount time. Resolves Launchpad issue #338914, reported by Tyler Hicks in 03/2009. https://bugs.launchpad.net/ecryptfs/+bug/338914 Signed-off-by: Tim Sally Signed-off-by: Tyler Hicks Signed-off-by: Herton Ronaldo Krzesinski --- fs/ecryptfs/main.c | 13 +++++++++++++ 1 file changed, 13 insertions(+) diff --git a/fs/ecryptfs/main.c b/fs/ecryptfs/main.c index c2a9c39..240832e 100644 --- a/fs/ecryptfs/main.c +++ b/fs/ecryptfs/main.c @@ -280,6 +280,7 @@ static int ecryptfs_parse_options(struct ecryptfs_sb_info *sbi, char *options, char *fnek_src; char *cipher_key_bytes_src; char *fn_cipher_key_bytes_src; + u8 cipher_code; *check_ruid = 0; @@ -421,6 +422,18 @@ static int ecryptfs_parse_options(struct ecryptfs_sb_info *sbi, char *options, && !fn_cipher_key_bytes_set) mount_crypt_stat->global_default_fn_cipher_key_bytes = mount_crypt_stat->global_default_cipher_key_size; + + cipher_code = ecryptfs_code_for_cipher_string( + mount_crypt_stat->global_default_cipher_name, + mount_crypt_stat->global_default_cipher_key_size); + if (!cipher_code) { + ecryptfs_printk(KERN_ERR, + "eCryptfs doesn't support cipher: %s", + mount_crypt_stat->global_default_cipher_name); + rc = -EINVAL; + goto out; + } + mutex_lock(&key_tfm_list_mutex); if (!ecryptfs_tfm_exists(mount_crypt_stat->global_default_cipher_name, NULL)) {