[PATCH v2 4/7] libfs: Support revalidation of encrypted case-insensitive dentries

Gabriel Krisman Bertazi
2023-04-22T00:03:39Z

From: Gabriel Krisman Bertazi <krisman@collabora.com>

Preserve the existing behavior for encrypted directories, by rejecting
negative dentries of encrypted+casefolded directories. This allows
generic_ci_d_revalidate to be used by filesystems with both features
enabled, as long as the directory is either casefolded or encrypted, but
not both at the same time.

Signed-off-by: Gabriel Krisman Bertazi <krisman@collabora.com>
---
fs/libfs.c | 8 ++++++--
1 file changed, 6 insertions(+), 2 deletions(-)

diff --git a/fs/libfs.c b/fs/libfs.c
index f8881e29c5d5..0886044db593 100644
--- a/fs/libfs.c
+++ b/fs/libfs.c
@@ -1478,6 +1478,9 @@ static inline int generic_ci_d_revalidate(struct dentry *dentry,
const struct inode *dir = READ_ONCE(parent->d_inode);

if (dir && needs_casefold(dir)) {
+ if (IS_ENCRYPTED(dir))
+ return 0;
+
if (!d_is_casefold_lookup(dentry))
return 0;

@@ -1497,7 +1500,8 @@ static inline int generic_ci_d_revalidate(struct dentry *dentry,
}
}
}
- return 1;
+
+ return fscrypt_d_revalidate(dentry, flags);
}

static const struct dentry_operations generic_ci_dentry_ops = {
@@ -1517,7 +1521,7 @@ static const struct dentry_operations generic_encrypted_dentry_ops = {
static const struct dentry_operations generic_encrypted_ci_dentry_ops = {
.d_hash = generic_ci_d_hash,
.d_compare = generic_ci_d_compare,
- .d_revalidate = fscrypt_d_revalidate,
+ .d_revalidate_name = generic_ci_d_revalidate,
};
#endif

--
2.40.0