Re: [syzbot] Re: [syzbot] [fscrypt?] WARNING in fscrypt_fname_siphash

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Subject: Re: [syzbot] [fscrypt?] WARNING in fscrypt_fname_siphash
Author: lizhi.xu@xxxxxxxxxxxxx

#syz test https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git 74eca356f6d4

diff --git a/fs/ext4/hash.c b/fs/ext4/hash.c
index deabe29da7fb..c8840cfc01dd 100644
--- a/fs/ext4/hash.c
+++ b/fs/ext4/hash.c
@@ -265,6 +265,10 @@ static int __ext4fs_dirhash(const struct inode *dir, const char *name, int len,
 		__u64	combined_hash;
 
 		if (fscrypt_has_encryption_key(dir)) {
+			if (!IS_CASEFOLDED(dir)) {
+				ext4_warning_inode(dir, "Siphash requires Casefolded file");
+				return -2;
+			}
 			combined_hash = fscrypt_fname_siphash(dir, &qname);
 		} else {
 			ext4_warning_inode(dir, "Siphash requires key");