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Diffstat (limited to 'fs')
-rw-r--r--fs/ext4/crypto.c56
-rw-r--r--fs/ext4/dir.c13
-rw-r--r--fs/ext4/ext4.h1
-rw-r--r--fs/ext4/namei.c18
-rw-r--r--fs/ext4/xattr.c32
5 files changed, 114 insertions, 6 deletions
diff --git a/fs/ext4/crypto.c b/fs/ext4/crypto.c
index 1a0835073663..1acac7fd21b2 100644
--- a/fs/ext4/crypto.c
+++ b/fs/ext4/crypto.c
@@ -469,3 +469,59 @@ uint32_t ext4_validate_encryption_key_size(uint32_t mode, uint32_t size)
return size;
return 0;
}
+
+/*
+ * Validate dentries for encrypted directories to make sure we aren't
+ * potentially caching stale data after a key has been added or
+ * removed.
+ */
+static int ext4_d_revalidate(struct dentry *dentry, unsigned int flags)
+{
+ struct inode *dir = d_inode(dentry->d_parent);
+ struct ext4_crypt_info *ci = EXT4_I(dir)->i_crypt_info;
+ int dir_has_key, cached_with_key;
+
+ if (!ext4_encrypted_inode(dir))
+ return 0;
+
+ if (ci && ci->ci_keyring_key &&
+ (ci->ci_keyring_key->flags & ((1 << KEY_FLAG_INVALIDATED) |
+ (1 << KEY_FLAG_REVOKED) |
+ (1 << KEY_FLAG_DEAD))))
+ ci = NULL;
+
+ /* this should eventually be an flag in d_flags */
+ cached_with_key = dentry->d_fsdata != NULL;
+ dir_has_key = (ci != NULL);
+
+ /*
+ * If the dentry was cached without the key, and it is a
+ * negative dentry, it might be a valid name. We can't check
+ * if the key has since been made available due to locking
+ * reasons, so we fail the validation so ext4_lookup() can do
+ * this check.
+ *
+ * We also fail the validation if the dentry was created with
+ * the key present, but we no longer have the key, or vice versa.
+ */
+ if ((!cached_with_key && d_is_negative(dentry)) ||
+ (!cached_with_key && dir_has_key) ||
+ (cached_with_key && !dir_has_key)) {
+#if 0 /* Revalidation debug */
+ char buf[80];
+ char *cp = simple_dname(dentry, buf, sizeof(buf));
+
+ if (IS_ERR(cp))
+ cp = (char *) "???";
+ pr_err("revalidate: %s %p %d %d %d\n", cp, dentry->d_fsdata,
+ cached_with_key, d_is_negative(dentry),
+ dir_has_key);
+#endif
+ return 0;
+ }
+ return 1;
+}
+
+const struct dentry_operations ext4_encrypted_d_ops = {
+ .d_revalidate = ext4_d_revalidate,
+};
diff --git a/fs/ext4/dir.c b/fs/ext4/dir.c
index 1d1bca74f844..33f5e2a50cf8 100644
--- a/fs/ext4/dir.c
+++ b/fs/ext4/dir.c
@@ -111,6 +111,12 @@ static int ext4_readdir(struct file *file, struct dir_context *ctx)
int dir_has_error = 0;
struct ext4_str fname_crypto_str = {.name = NULL, .len = 0};
+ if (ext4_encrypted_inode(inode)) {
+ err = ext4_get_encryption_info(inode);
+ if (err && err != -ENOKEY)
+ return err;
+ }
+
if (is_dx_dir(inode)) {
err = ext4_dx_readdir(file, ctx);
if (err != ERR_BAD_DX_DIR) {
@@ -157,8 +163,11 @@ static int ext4_readdir(struct file *file, struct dir_context *ctx)
index, 1);
file->f_ra.prev_pos = (loff_t)index << PAGE_CACHE_SHIFT;
bh = ext4_bread(NULL, inode, map.m_lblk, 0);
- if (IS_ERR(bh))
- return PTR_ERR(bh);
+ if (IS_ERR(bh)) {
+ err = PTR_ERR(bh);
+ bh = NULL;
+ goto errout;
+ }
}
if (!bh) {
diff --git a/fs/ext4/ext4.h b/fs/ext4/ext4.h
index 614b79c4576e..c1b4f6ab2148 100644
--- a/fs/ext4/ext4.h
+++ b/fs/ext4/ext4.h
@@ -2258,6 +2258,7 @@ struct page *ext4_encrypt(struct inode *inode,
struct page *plaintext_page);
int ext4_decrypt(struct page *page);
int ext4_encrypted_zeroout(struct inode *inode, struct ext4_extent *ex);
+extern const struct dentry_operations ext4_encrypted_d_ops;
#ifdef CONFIG_EXT4_FS_ENCRYPTION
int ext4_init_crypto(void);
diff --git a/fs/ext4/namei.c b/fs/ext4/namei.c
index 06c3afcbfac8..c9aad3b8951f 100644
--- a/fs/ext4/namei.c
+++ b/fs/ext4/namei.c
@@ -1558,6 +1558,24 @@ static struct dentry *ext4_lookup(struct inode *dir, struct dentry *dentry, unsi
struct ext4_dir_entry_2 *de;
struct buffer_head *bh;
+ if (ext4_encrypted_inode(dir)) {
+ int res = ext4_get_encryption_info(dir);
+
+ /*
+ * This should be a properly defined flag for
+ * dentry->d_flags when we uplift this to the VFS.
+ * d_fsdata is set to (void *) 1 if if the dentry is
+ * created while the directory was encrypted and we
+ * don't have access to the key.
+ */
+ dentry->d_fsdata = NULL;
+ if (ext4_encryption_info(dir))
+ dentry->d_fsdata = (void *) 1;
+ d_set_d_op(dentry, &ext4_encrypted_d_ops);
+ if (res && res != -ENOKEY)
+ return ERR_PTR(res);
+ }
+
if (dentry->d_name.len > EXT4_NAME_LEN)
return ERR_PTR(-ENAMETOOLONG);
diff --git a/fs/ext4/xattr.c b/fs/ext4/xattr.c
index 6b6b3e751f8c..06fd5f7f993d 100644
--- a/fs/ext4/xattr.c
+++ b/fs/ext4/xattr.c
@@ -232,6 +232,27 @@ ext4_xattr_check_block(struct inode *inode, struct buffer_head *bh)
return error;
}
+static int
+__xattr_check_inode(struct inode *inode, struct ext4_xattr_ibody_header *header,
+ void *end, const char *function, unsigned int line)
+{
+ struct ext4_xattr_entry *entry = IFIRST(header);
+ int error = -EFSCORRUPTED;
+
+ if (((void *) header >= end) ||
+ (header->h_magic != le32_to_cpu(EXT4_XATTR_MAGIC)))
+ goto errout;
+ error = ext4_xattr_check_names(entry, end, entry);
+errout:
+ if (error)
+ __ext4_error_inode(inode, function, line, 0,
+ "corrupted in-inode xattr");
+ return error;
+}
+
+#define xattr_check_inode(inode, header, end) \
+ __xattr_check_inode((inode), (header), (end), __func__, __LINE__)
+
static inline int
ext4_xattr_check_entry(struct ext4_xattr_entry *entry, size_t size)
{
@@ -343,7 +364,7 @@ ext4_xattr_ibody_get(struct inode *inode, int name_index, const char *name,
header = IHDR(inode, raw_inode);
entry = IFIRST(header);
end = (void *)raw_inode + EXT4_SB(inode->i_sb)->s_inode_size;
- error = ext4_xattr_check_names(entry, end, entry);
+ error = xattr_check_inode(inode, header, end);
if (error)
goto cleanup;
error = ext4_xattr_find_entry(&entry, name_index, name,
@@ -474,7 +495,7 @@ ext4_xattr_ibody_list(struct dentry *dentry, char *buffer, size_t buffer_size)
raw_inode = ext4_raw_inode(&iloc);
header = IHDR(inode, raw_inode);
end = (void *)raw_inode + EXT4_SB(inode->i_sb)->s_inode_size;
- error = ext4_xattr_check_names(IFIRST(header), end, IFIRST(header));
+ error = xattr_check_inode(inode, header, end);
if (error)
goto cleanup;
error = ext4_xattr_list_entries(dentry, IFIRST(header),
@@ -990,8 +1011,7 @@ int ext4_xattr_ibody_find(struct inode *inode, struct ext4_xattr_info *i,
is->s.here = is->s.first;
is->s.end = (void *)raw_inode + EXT4_SB(inode->i_sb)->s_inode_size;
if (ext4_test_inode_state(inode, EXT4_STATE_XATTR)) {
- error = ext4_xattr_check_names(IFIRST(header), is->s.end,
- IFIRST(header));
+ error = xattr_check_inode(inode, header, is->s.end);
if (error)
return error;
/* Find the named attribute. */
@@ -1288,6 +1308,10 @@ retry:
last = entry;
total_ino = sizeof(struct ext4_xattr_ibody_header);
+ error = xattr_check_inode(inode, header, end);
+ if (error)
+ goto cleanup;
+
free = ext4_xattr_free_space(last, &min_offs, base, &total_ino);
if (free >= new_extra_isize) {
entry = IFIRST(header);