[PATCH v3] fs: add the tuncate check of exfat

From: MIngyi Cong
Date: Thu Mar 16 2023 - 10:45:32 EST


EXFAT will fill zero data in truncated range.
Fix this by adding EXFAT_SUPER_MAGIC check.

Signed-off-by: MIngyi Cong <congmingyi@xxxxxxxxx>
---
V1 -> V2: add the truncate check of hfs and remove EXFAT_SUPER_MAGIC in magic.h
V2 -> V3: remove the truncate check of hfs and hfsplus
fs/ksmbd/smb2pdu.c | 3 ++-
1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/fs/ksmbd/smb2pdu.c b/fs/ksmbd/smb2pdu.c
index 0685c1c77b9f..3f2e34936b8d 100644
--- a/fs/ksmbd/smb2pdu.c
+++ b/fs/ksmbd/smb2pdu.c
@@ -5746,7 +5746,8 @@ static int set_end_of_file_info(struct ksmbd_work *work, struct ksmbd_file *fp,
* truncate of some filesystem like FAT32 fill zero data in
* truncated range.
*/
- if (inode->i_sb->s_magic != MSDOS_SUPER_MAGIC) {
+ if (inode->i_sb->s_magic != MSDOS_SUPER_MAGIC ||
+ inode->i_sb->s_magic != EXFAT_SUPER_MAGIC) {
ksmbd_debug(SMB, "truncated to newsize %lld\n", newsize);
rc = ksmbd_vfs_truncate(work, fp, newsize);
if (rc) {
--
2.34.1