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Message-ID: <tencent_CAB0DDA2192E4FE30DA8A5990DFD923A5D07@qq.com>
From: Edward Adam Davis <eadavis@qq.com>
To: syzbot+efde959319469ff8d4d7@syzkaller.appspotmail.com
Cc: linux-kernel@vger.kernel.org,
	syzkaller-bugs@googlegroups.com
Subject: Re: [syzbot] [hfs?] KMSAN: uninit-value in copy_name
Date: Tue, 21 May 2024 08:40:32 +0800
In-Reply-To: <00000000000037162f0618b6fefb@google.com>
References: <00000000000037162f0618b6fefb@google.com>
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please test uiv in copy_name

#syz test https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git a5131c3fdf26

diff --git a/fs/hfsplus/unicode.c b/fs/hfsplus/unicode.c
index 73342c925a4b..8e97df12375d 100644
--- a/fs/hfsplus/unicode.c
+++ b/fs/hfsplus/unicode.c
@@ -234,6 +234,7 @@ int hfsplus_uni2asc(struct super_block *sb,
 		}
 done:
 		res = nls->uni2char(cc, op, len);
+		printk("res: %d, cc: %d, op:%p, len: %d, ustrlen: %d, %s\n", res, cc, op, len, ustrlen, __func__);
 		if (res < 0) {
 			if (res == -ENAMETOOLONG)
 				goto out;
diff --git a/fs/hfsplus/xattr.c b/fs/hfsplus/xattr.c
index 9c9ff6b8c6f7..a02903a929a6 100644
--- a/fs/hfsplus/xattr.c
+++ b/fs/hfsplus/xattr.c
@@ -733,14 +733,16 @@ ssize_t hfsplus_listxattr(struct dentry *dentry, char *buffer, size_t size)
 			goto end_listxattr;
 
 		xattr_name_len = NLS_MAX_CHARSET_SIZE * HFSPLUS_ATTR_MAX_STRLEN;
+		printk("1sb: %p, xnl: %d, %s\n", strbuf, xattr_name_len, __func__);
 		if (hfsplus_uni2asc(inode->i_sb,
 			(const struct hfsplus_unistr *)&fd.key->attr.key_name,
-					strbuf, &xattr_name_len)) {
+					strbuf, &xattr_name_len) || !xattr_name_len) {
 			pr_err("unicode conversion failed\n");
 			res = -EIO;
 			goto end_listxattr;
 		}
 
+		printk("3s:%d, buf:%p, res:%d, sb: %s, xnl: %d, %s\n", size, buffer, res, strbuf, xattr_name_len, __func__);
 		if (!buffer || !size) {
 			if (can_list(strbuf))
 				res += name_len(strbuf, xattr_name_len);