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| author |   Theodore Ts'o <tytso@mit.edu> | 2016-02-08 00:54:26 -0500 |
|---|---|---|
| committer | Theodore Ts'o <tytso@mit.edu> | 2016-02-08 00:54:26 -0500 |
| commit | ff978b09f973db0d0597704eba350a994d7729e6 (patch) | |
| tree | 75f1066159641b2e1cc9891a7d6ccd5cb3b29826 /fs/ext4 | |
| parent | ext4 crypto: revalidate dentry after adding or removing the key (diff) | |
| download | linux-dev-ff978b09f973db0d0597704eba350a994d7729e6.tar.xz linux-dev-ff978b09f973db0d0597704eba350a994d7729e6.zip | |
ext4 crypto: move context consistency check to ext4_file_open()
In the case where the per-file key for the directory is cached, but
root does not have access to the key needed to derive the per-file key
for the files in the directory, we allow the lookup to succeed, so
that lstat(2) and unlink(2) can suceed. However, if a program tries
to open the file, it will get an ENOKEY error.
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Diffstat (limited to 'fs/ext4')
| -rw-r--r-- | fs/ext4/file.c | 9 | ||||
| -rw-r--r-- | fs/ext4/namei.c | 8 |
2 files changed, 15 insertions, 2 deletions
diff --git a/fs/ext4/file.c b/fs/ext4/file.c index 1126436dada1..474f1a4d2ca8 100644 --- a/fs/ext4/file.c +++ b/fs/ext4/file.c @@ -350,6 +350,7 @@ static int ext4_file_open(struct inode * inode, struct file * filp) struct super_block *sb = inode->i_sb; struct ext4_sb_info *sbi = EXT4_SB(inode->i_sb); struct vfsmount *mnt = filp->f_path.mnt; + struct inode *dir = filp->f_path.dentry->d_parent->d_inode; struct path path; char buf[64], *cp; int ret; @@ -393,6 +394,14 @@ static int ext4_file_open(struct inode * inode, struct file * filp) if (ext4_encryption_info(inode) == NULL) return -ENOKEY; } + if (ext4_encrypted_inode(dir) && + !ext4_is_child_context_consistent_with_parent(dir, inode)) { + ext4_warning(inode->i_sb, + "Inconsistent encryption contexts: %lu/%lu\n", + (unsigned long) dir->i_ino, + (unsigned long) inode->i_ino); + return -EPERM; + } /* * Set up the jbd2_inode if we are opening the inode for * writing and the journal is present diff --git a/fs/ext4/namei.c b/fs/ext4/namei.c index 5de8483f0062..48e4b8907826 100644 --- a/fs/ext4/namei.c +++ b/fs/ext4/namei.c @@ -1603,11 +1603,15 @@ static struct dentry *ext4_lookup(struct inode *dir, struct dentry *dentry, unsi return ERR_PTR(-EFSCORRUPTED); } if (!IS_ERR(inode) && ext4_encrypted_inode(dir) && - (S_ISREG(inode->i_mode) || S_ISDIR(inode->i_mode) || - S_ISLNK(inode->i_mode)) && + (S_ISDIR(inode->i_mode) || S_ISLNK(inode->i_mode)) && !ext4_is_child_context_consistent_with_parent(dir, inode)) { + int nokey = ext4_encrypted_inode(inode) && + !ext4_encryption_info(inode); + iput(inode); + if (nokey) + return ERR_PTR(-ENOKEY); ext4_warning(inode->i_sb, "Inconsistent encryption contexts: %lu/%lu\n", (unsigned long) dir->i_ino, |