[PATCH 1/2] fs/ntfs3: Update log->page_{mask,bits} if log->page_size changed

[Huacai Chen]

If an NTFS file system is mounted to another system with different
PAGE_SIZE from the original system, log->page_size will change in
log_replay(), but log->page_{mask,bits} don't change correspondingly.
This will cause a panic because "u32 bytes = log->page_size - page_off"
will get a negative value in the later read_log_page().

Cc: stable@xxxxxxxxxxxxxxx
Fixes: b46acd6a6a627d876898e ("fs/ntfs3: Add NTFS journal")
Signed-off-by: Huacai Chen <chenhuacai@xxxxxxxxxxx>
---
 fs/ntfs3/fslog.c | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/fs/ntfs3/fslog.c b/fs/ntfs3/fslog.c
index 855519713bf7..19c448093df7 100644
--- a/fs/ntfs3/fslog.c
+++ b/fs/ntfs3/fslog.c
@@ -3914,6 +3914,9 @@ int log_replay(struct ntfs_inode *ni, bool *initialized)
 		goto out;
 	}
 
+	log->page_mask = log->page_size - 1;
+	log->page_bits = blksize_bits(log->page_size);
+
 	/* If the file size has shrunk then we won't mount it. */
 	if (log->l_size < le64_to_cpu(ra2->l_size)) {
 		err = -EINVAL;
-- 
2.43.0