commit 471fbbea7ff7 ("ext4: handle casefolding with encryption") is
missing a few checks for the encryption key which are needed to
support deleting enrypted casefolded files when the key is not
present.
Note from ebiggers:
(These checks for the encryption key are still racy since they happen
too late, but apparently they worked well enough...)
This bug made it impossible to delete encrypted+casefolded directories
without the encryption key, due to errors like:
W : EXT4-fs warning (device vdc): __ext4fs_dirhash:270: inode #49202: comm Binder:378_4: Siphash requires key
Repro steps in kvm-xfstests test appliance:
mkfs.ext4 -F -E encoding=utf8 -O encrypt /dev/vdc
mount /vdc
mkdir /vdc/dir
chattr +F /vdc/dir
keyid=$(head -c 64 /dev/zero | xfs_io -c add_enckey /vdc | awk '{print $NF}')
xfs_io -c "set_encpolicy $keyid" /vdc/dir
for i in `seq 1 100`; do
mkdir /vdc/dir/$i
done
xfs_io -c "rm_enckey $keyid" /vdc
rm -rf /vdc/dir # fails with the bug
Fixes: 471fbbea7ff7 ("ext4: handle casefolding with encryption")
Signed-off-by: Daniel Rosenberg <drosen@xxxxxxxxxx>
---
fs/ext4/namei.c | 6 ++++--
1 file changed, 4 insertions(+), 2 deletions(-)
diff --git a/fs/ext4/namei.c b/fs/ext4/namei.c
index afb9d05a99ba..a4af26d4459a 100644
--- a/fs/ext4/namei.c
+++ b/fs/ext4/namei.c
@@ -1376,7 +1376,8 @@ int ext4_fname_setup_ci_filename(struct inode *dir, const struct qstr *iname,
struct dx_hash_info *hinfo = &name->hinfo;
int len;
- if (!IS_CASEFOLDED(dir) || !dir->i_sb->s_encoding) {
+ if (!IS_CASEFOLDED(dir) || !dir->i_sb->s_encoding ||
+ (IS_ENCRYPTED(dir) && !fscrypt_has_encryption_key(dir))) {
cf_name->name = NULL;
return 0;
}
@@ -1427,7 +1428,8 @@ static bool ext4_match(struct inode *parent,
#endif
#ifdef CONFIG_UNICODE
- if (parent->i_sb->s_encoding && IS_CASEFOLDED(parent)) {
+ if (parent->i_sb->s_encoding && IS_CASEFOLDED(parent) &&
+ (!IS_ENCRYPTED(parent) || fscrypt_has_encryption_key(parent))) {
if (fname->cf_name.name) {
struct qstr cf = {.name = fname->cf_name.name,
.len = fname->cf_name.len};
--
2.31.1.818.g46aad6cb9e-goog
