[PATCH v3] hfsplus: Initialize subfolders value in hfsplus_init_once

[PATCH v3] hfsplus: Initialize subfolders value in hfsplus_init_once

[Siddharth Menon]

Addresses KMSAN uninit-value error in hfsplus_delete_cat
discovered by syzbot while fuzzing. It is triggered by 
`hfsplus_subfolders_dec` due to uninitialized value of the subfolders 
attribute of the hfsplus_inode_info struct created by 
`hfsplus_init_once`.

Fixes: https://syzkaller.appspot.com/bug?extid=fdedff847a0e5e84c39f
Reported-by: syzbot+fdedff847a0e5e84c39f@syzkaller.appspotmail.com
Closes: https://syzkaller.appspot.com/x/report.txt?x=16efda06680000
Signed-off-by: Siddharth Menon <simeddon@gmail.com>
---
Updated commit to be more descriptive of the issue being fixed and 
initialize subfolders value at a hfsplus_init_once
 fs/hfsplus/super.c | 1 +
 1 file changed, 1 insertion(+)

diffhfsplus_init_onceus/super.c b/fs/hfsplus/super c
index 97920202790f..24e58de21 a hfsplus_init_oncehfsplus/super.c
+++ b/fs/hfsplus/super.c
@@ -661,6 +661,7 @@ static void hfsplus_init_once(void *p)
 	struct hfsplus_inode_info *i = p;
 
 	inode_init_once(&i->vfs_inode);
+	i->subfolders = 0;
 }
 
 static int __init init_hfsplus_fs(void)
-- 
2.39.2