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| author | Tyler Hicks | 2011-11-05 18:45:08 +0100 |
|---|---|---|
| committer | Tyler Hicks | 2012-02-16 23:06:21 +0100 |
| commit | 4a26620df451ad46151ad21d711ed43e963c004e (patch) | |
| tree | bf035ea6a656b3e19fe93bf37991632cad96d971 /fs/ecryptfs/super.c | |
| parent | i387: fix sense of sanity check (diff) | |
| download | kernel-qcow2-linux-4a26620df451ad46151ad21d711ed43e963c004e.tar.gz kernel-qcow2-linux-4a26620df451ad46151ad21d711ed43e963c004e.tar.xz kernel-qcow2-linux-4a26620df451ad46151ad21d711ed43e963c004e.zip | |
eCryptfs: Improve statfs reporting
statfs() calls on eCryptfs files returned the wrong filesystem type and,
when using filename encryption, the wrong maximum filename length.
If mount-wide filename encryption is enabled, the cipher block size and
the lower filesystem's max filename length will determine the max
eCryptfs filename length. Pre-tested, known good lengths are used when
the lower filesystem's namelen is 255 and a cipher with 8 or 16 byte
block sizes is used. In other, less common cases, we fall back to a safe
rounded-down estimate when determining the eCryptfs namelen.
https://launchpad.net/bugs/885744
Signed-off-by: Tyler Hicks <tyhicks@canonical.com>
Reported-by: Kees Cook <keescook@chromium.org>
Reviewed-by: Kees Cook <keescook@chromium.org>
Reviewed-by: John Johansen <john.johansen@canonical.com>
Diffstat (limited to 'fs/ecryptfs/super.c')
| -rw-r--r-- | fs/ecryptfs/super.c | 14 |
1 files changed, 13 insertions, 1 deletions
diff --git a/fs/ecryptfs/super.c b/fs/ecryptfs/super.c index 9df7fd6e0c39..cf152823bbf4 100644 --- a/fs/ecryptfs/super.c +++ b/fs/ecryptfs/super.c @@ -30,6 +30,8 @@ #include <linux/seq_file.h> #include <linux/file.h> #include <linux/crypto.h> +#include <linux/statfs.h> +#include <linux/magic.h> #include "ecryptfs_kernel.h" struct kmem_cache *ecryptfs_inode_info_cache; @@ -102,10 +104,20 @@ static void ecryptfs_destroy_inode(struct inode *inode) static int ecryptfs_statfs(struct dentry *dentry, struct kstatfs *buf) { struct dentry *lower_dentry = ecryptfs_dentry_to_lower(dentry); + int rc; if (!lower_dentry->d_sb->s_op->statfs) return -ENOSYS; - return lower_dentry->d_sb->s_op->statfs(lower_dentry, buf); + + rc = lower_dentry->d_sb->s_op->statfs(lower_dentry, buf); + if (rc) + return rc; + + buf->f_type = ECRYPTFS_SUPER_MAGIC; + rc = ecryptfs_set_f_namelen(&buf->f_namelen, buf->f_namelen, + &ecryptfs_superblock_to_private(dentry->d_sb)->mount_crypt_stat); + + return rc; } /** |