1 files changed, 25 insertions, 8 deletions

diff --git a/fs/ext4/hash.c b/fs/ext4/hash.c
index 3e133793a5a3..147b5241dd94 100644
--- a/fs/ext4/hash.c
+++ b/fs/ext4/hash.c
@@ -197,7 +197,7 @@ static void str2hashbuf_unsigned(const char *msg, int len, __u32 *buf, int num)
  * represented, and whether or not the returned hash is 32 bits or 64
  * bits.  32 bit hashes will return 0 for the minor hash.
  */
-static int __ext4fs_dirhash(const char *name, int len,
+static int __ext4fs_dirhash(const struct inode *dir, const char *name, int len,
 			    struct dx_hash_info *hinfo)
 {
 	__u32	hash;
@@ -233,7 +233,7 @@ static int __ext4fs_dirhash(const char *name, int len,
 		break;
 	case DX_HASH_HALF_MD4_UNSIGNED:
 		str2hashbuf = str2hashbuf_unsigned;
-		/* fall through */
+		fallthrough;
 	case DX_HASH_HALF_MD4:
 		p = name;
 		while (len > 0) {
@@ -247,7 +247,7 @@ static int __ext4fs_dirhash(const char *name, int len,
 		break;
 	case DX_HASH_TEA_UNSIGNED:
 		str2hashbuf = str2hashbuf_unsigned;
-		/* fall through */
+		fallthrough;
 	case DX_HASH_TEA:
 		p = name;
 		while (len > 0) {
@@ -259,6 +259,22 @@ static int __ext4fs_dirhash(const char *name, int len,
 		hash = buf[0];
 		minor_hash = buf[1];
 		break;
+	case DX_HASH_SIPHASH:
+	{
+		struct qstr qname = QSTR_INIT(name, len);
+		__u64	combined_hash;
+
+		if (fscrypt_has_encryption_key(dir)) {
+			combined_hash = fscrypt_fname_siphash(dir, &qname);
+		} else {
+			ext4_warning_inode(dir, "Siphash requires key");
+			return -1;
+		}
+
+		hash = (__u32)(combined_hash >> 32);
+		minor_hash = (__u32)combined_hash;
+		break;
+	}
 	default:
 		hinfo->hash = 0;
 		return -1;
@@ -274,13 +290,14 @@ static int __ext4fs_dirhash(const char *name, int len,
 int ext4fs_dirhash(const struct inode *dir, const char *name, int len,
 		   struct dx_hash_info *hinfo)
 {
-#ifdef CONFIG_UNICODE
-	const struct unicode_map *um = EXT4_SB(dir->i_sb)->s_encoding;
+#if IS_ENABLED(CONFIG_UNICODE)
+	const struct unicode_map *um = dir->i_sb->s_encoding;
 	int r, dlen;
 	unsigned char *buff;
 	struct qstr qstr = {.name = name, .len = len };
 
-	if (len && IS_CASEFOLDED(dir) && um) {
+	if (len && IS_CASEFOLDED(dir) && um &&
+	   (!IS_ENCRYPTED(dir) || fscrypt_has_encryption_key(dir))) {
 		buff = kzalloc(sizeof(char) * PATH_MAX, GFP_KERNEL);
 		if (!buff)
 			return -ENOMEM;
@@ -291,12 +308,12 @@ int ext4fs_dirhash(const struct inode *dir, const char *name, int len,
 			goto opaque_seq;
 		}
 
-		r = __ext4fs_dirhash(buff, dlen, hinfo);
+		r = __ext4fs_dirhash(dir, buff, dlen, hinfo);
 
 		kfree(buff);
 		return r;
 	}
 opaque_seq:
 #endif
-	return __ext4fs_dirhash(name, len, hinfo);
+	return __ext4fs_dirhash(dir, name, len, hinfo);
 }