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authorLinus Torvalds <torvalds@linux-foundation.org>2023-02-20 23:29:27 +0300
committerLinus Torvalds <torvalds@linux-foundation.org>2023-02-20 23:29:27 +0300
commitf18f9845f2f10d3d1fc63e4ad16ee52d2d9292fa (patch)
tree2c959ab3f3bdb1280dd741664daef8edd9532c99 /fs/crypto
parentdc483c851ff9a3505069cb326221dc0242d44015 (diff)
parent097d7c1fcb8d4b52c62a36f94b8f18bc21a24934 (diff)
downloadlinux-f18f9845f2f10d3d1fc63e4ad16ee52d2d9292fa.tar.xz
Merge tag 'fscrypt-for-linus' of git://git.kernel.org/pub/scm/fs/fscrypt/linux
Pull fscrypt updates from Eric Biggers: "Simplify the implementation of the test_dummy_encryption mount option by adding the 'test dummy key' on-demand" * tag 'fscrypt-for-linus' of git://git.kernel.org/pub/scm/fs/fscrypt/linux: fscrypt: clean up fscrypt_add_test_dummy_key() fs/super.c: stop calling fscrypt_destroy_keyring() from __put_super() f2fs: stop calling fscrypt_add_test_dummy_key() ext4: stop calling fscrypt_add_test_dummy_key() fscrypt: add the test dummy encryption key on-demand
Diffstat (limited to 'fs/crypto')
-rw-r--r--fs/crypto/fscrypt_private.h4
-rw-r--r--fs/crypto/keyring.c26
-rw-r--r--fs/crypto/keysetup.c23
-rw-r--r--fs/crypto/policy.c3
4 files changed, 33 insertions, 23 deletions
diff --git a/fs/crypto/fscrypt_private.h b/fs/crypto/fscrypt_private.h
index 316a778cec0f..0fec2dfc36eb 100644
--- a/fs/crypto/fscrypt_private.h
+++ b/fs/crypto/fscrypt_private.h
@@ -573,6 +573,9 @@ fscrypt_find_master_key(struct super_block *sb,
int fscrypt_get_test_dummy_key_identifier(
u8 key_identifier[FSCRYPT_KEY_IDENTIFIER_SIZE]);
+int fscrypt_add_test_dummy_key(struct super_block *sb,
+ struct fscrypt_key_specifier *key_spec);
+
int fscrypt_verify_key_added(struct super_block *sb,
const u8 identifier[FSCRYPT_KEY_IDENTIFIER_SIZE]);
@@ -651,6 +654,7 @@ bool fscrypt_policies_equal(const union fscrypt_policy *policy1,
const union fscrypt_policy *policy2);
int fscrypt_policy_to_key_spec(const union fscrypt_policy *policy,
struct fscrypt_key_specifier *key_spec);
+const union fscrypt_policy *fscrypt_get_dummy_policy(struct super_block *sb);
bool fscrypt_supported_policy(const union fscrypt_policy *policy_u,
const struct inode *inode);
int fscrypt_policy_from_context(union fscrypt_policy *policy_u,
diff --git a/fs/crypto/keyring.c b/fs/crypto/keyring.c
index 78dd2ff306bd..78086f8dbda5 100644
--- a/fs/crypto/keyring.c
+++ b/fs/crypto/keyring.c
@@ -211,10 +211,6 @@ static int allocate_filesystem_keyring(struct super_block *sb)
* are still available at this time; this is important because after user file
* accesses have been allowed, this function may need to evict keys from the
* keyslots of an inline crypto engine, which requires the block device(s).
- *
- * This is also called when the super_block is being freed. This is needed to
- * avoid a memory leak if mounting fails after the "test_dummy_encryption"
- * option was processed, as in that case the unmount-time call isn't made.
*/
void fscrypt_destroy_keyring(struct super_block *sb)
{
@@ -778,34 +774,26 @@ out:
/**
* fscrypt_add_test_dummy_key() - add the test dummy encryption key
* @sb: the filesystem instance to add the key to
- * @dummy_policy: the encryption policy for test_dummy_encryption
+ * @key_spec: the key specifier of the test dummy encryption key
*
- * If needed, add the key for the test_dummy_encryption mount option to the
- * filesystem. To prevent misuse of this mount option, a per-boot random key is
- * used instead of a hardcoded one. This makes it so that any encrypted files
- * created using this option won't be accessible after a reboot.
+ * Add the key for the test_dummy_encryption mount option to the filesystem. To
+ * prevent misuse of this mount option, a per-boot random key is used instead of
+ * a hardcoded one. This makes it so that any encrypted files created using
+ * this option won't be accessible after a reboot.
*
* Return: 0 on success, -errno on failure
*/
int fscrypt_add_test_dummy_key(struct super_block *sb,
- const struct fscrypt_dummy_policy *dummy_policy)
+ struct fscrypt_key_specifier *key_spec)
{
- const union fscrypt_policy *policy = dummy_policy->policy;
- struct fscrypt_key_specifier key_spec;
struct fscrypt_master_key_secret secret;
int err;
- if (!policy)
- return 0;
- err = fscrypt_policy_to_key_spec(policy, &key_spec);
- if (err)
- return err;
fscrypt_get_test_dummy_secret(&secret);
- err = add_master_key(sb, &secret, &key_spec);
+ err = add_master_key(sb, &secret, key_spec);
wipe_master_key_secret(&secret);
return err;
}
-EXPORT_SYMBOL_GPL(fscrypt_add_test_dummy_key);
/*
* Verify that the current user has added a master key with the given identifier
diff --git a/fs/crypto/keysetup.c b/fs/crypto/keysetup.c
index 94757ccd3056..aa94fba9d17e 100644
--- a/fs/crypto/keysetup.c
+++ b/fs/crypto/keysetup.c
@@ -438,6 +438,7 @@ static int setup_file_encryption_key(struct fscrypt_info *ci,
bool need_dirhash_key,
struct fscrypt_master_key **mk_ret)
{
+ struct super_block *sb = ci->ci_inode->i_sb;
struct fscrypt_key_specifier mk_spec;
struct fscrypt_master_key *mk;
int err;
@@ -450,8 +451,26 @@ static int setup_file_encryption_key(struct fscrypt_info *ci,
if (err)
return err;
- mk = fscrypt_find_master_key(ci->ci_inode->i_sb, &mk_spec);
- if (!mk) {
+ mk = fscrypt_find_master_key(sb, &mk_spec);
+ if (unlikely(!mk)) {
+ const union fscrypt_policy *dummy_policy =
+ fscrypt_get_dummy_policy(sb);
+
+ /*
+ * Add the test_dummy_encryption key on-demand. In principle,
+ * it should be added at mount time. Do it here instead so that
+ * the individual filesystems don't need to worry about adding
+ * this key at mount time and cleaning up on mount failure.
+ */
+ if (dummy_policy &&
+ fscrypt_policies_equal(dummy_policy, &ci->ci_policy)) {
+ err = fscrypt_add_test_dummy_key(sb, &mk_spec);
+ if (err)
+ return err;
+ mk = fscrypt_find_master_key(sb, &mk_spec);
+ }
+ }
+ if (unlikely(!mk)) {
if (ci->ci_policy.version != FSCRYPT_POLICY_V1)
return -ENOKEY;
diff --git a/fs/crypto/policy.c b/fs/crypto/policy.c
index fa09c925bda8..3b5fcb6402ea 100644
--- a/fs/crypto/policy.c
+++ b/fs/crypto/policy.c
@@ -53,8 +53,7 @@ int fscrypt_policy_to_key_spec(const union fscrypt_policy *policy,
}
}
-static const union fscrypt_policy *
-fscrypt_get_dummy_policy(struct super_block *sb)
+const union fscrypt_policy *fscrypt_get_dummy_policy(struct super_block *sb)
{
if (!sb->s_cop->get_dummy_policy)
return NULL;