From b5b18160a3e7a9f55e3528d77051670cca6d9314 Mon Sep 17 00:00:00 2001 From: Jan Kara Date: Tue, 27 Oct 2020 14:27:51 +0100 Subject: [PATCH] ext4: fix mmap write protection for data=journal mode Commit afb585a97f81 "ext4: data=journal: write-protect pages on j_submit_inode_data_buffers()") added calls ext4_jbd2_inode_add_write() to track inode ranges whose mappings need to get write-protected during transaction commits. However the added calls use wrong start of a range (0 instead of page offset) and so write protection is not necessarily effective. Use correct range start to fix the problem. Fixes: afb585a97f81 ("ext4: data=journal: write-protect pages on j_submit_inode_data_buffers()") Signed-off-by: Jan Kara Link: https://lore.kernel.org/r/20201027132751.29858-1-jack@suse.cz Signed-off-by: Theodore Ts'o --- fs/ext4/inode.c | 5 +++-- 1 file changed, 3 insertions(+), 2 deletions(-) diff --git a/fs/ext4/inode.c b/fs/ext4/inode.c index 520a0209451e..b96a18679a27 100644 --- a/fs/ext4/inode.c +++ b/fs/ext4/inode.c @@ -1918,7 +1918,7 @@ static int __ext4_journalled_writepage(struct page *page, } if (ret == 0) ret = err; - err = ext4_jbd2_inode_add_write(handle, inode, 0, len); + err = ext4_jbd2_inode_add_write(handle, inode, page_offset(page), len); if (ret == 0) ret = err; EXT4_I(inode)->i_datasync_tid = handle->h_transaction->t_tid; @@ -6159,7 +6159,8 @@ retry_alloc: if (ext4_walk_page_buffers(handle, page_buffers(page), 0, len, NULL, write_end_fn)) goto out_error; - if (ext4_jbd2_inode_add_write(handle, inode, 0, len)) + if (ext4_jbd2_inode_add_write(handle, inode, + page_offset(page), len)) goto out_error; ext4_set_inode_state(inode, EXT4_STATE_JDATA); } else {