6.6-stable review patch. If anyone has any objections, please let me know. ------------------ From: Huiwen He [ Upstream commit d7d2adcd022baade5cab65ca492ce63421ce3a6e ] Punching a hole after a large buffered write may leave the range reported as data. Reproduce it with: xfs_io -f \ -c "pwrite -b 3m -S 0x61 0 3m" \ -c "fpunch 1m 1m" \ -c "seek -h 0" \ -c "seek -d 1m" \ /mnt/test/repro Punching 1 MiB at offset 1 MiB should produce: 0 1 MiB 2 MiB 3 MiB | DATA | HOLE | DATA | EOF Instead, the entire file is reported as data. SEEK_HOLE(0) returns EOF, and SEEK_DATA(1M) returns 1M. This happens because a dirty folio spanning the punched range can be written back after the punch and refill the hole. Fix this by flushing and waiting for dirty data in the punched range before invalidating the page cache and issuing FSCTL_SET_ZERO_DATA. The xfstests generic/539 pass against Samba/ksmbd with this change. Signed-off-by: Huiwen He Reviewed-by: ChenXiaoSong Signed-off-by: Steve French Signed-off-by: Sasha Levin --- fs/smb/client/smb2ops.c | 9 +++++++++ 1 file changed, 9 insertions(+) diff --git a/fs/smb/client/smb2ops.c b/fs/smb/client/smb2ops.c index 07ed4bfd40977..956d1dc8bca39 100644 --- a/fs/smb/client/smb2ops.c +++ b/fs/smb/client/smb2ops.c @@ -3328,6 +3328,15 @@ static long smb3_punch_hole(struct file *file, struct cifs_tcon *tcon, goto out; filemap_invalidate_lock(inode->i_mapping); + /* + * Flush dirty data first, otherwise a dirty folio spanning the punched + * range may be written back after the ioctl and refill the hole. + */ + rc = filemap_write_and_wait_range(inode->i_mapping, offset, + offset + len - 1); + if (rc < 0) + goto unlock; + /* * We implement the punch hole through ioctl, so we need remove the page * caches first, otherwise the data may be inconsistent with the server. -- 2.53.0