From 9c8b7a293f50253e694f19161c045817a938e551 Mon Sep 17 00:00:00 2001 From: David Howells Date: Tue, 23 Aug 2022 14:07:55 +0100 Subject: [PATCH] smb3: fix temporary data corruption in insert range insert range doesn't discard the affected cached region so can risk temporarily corrupting file data. Also includes some minor cleanup (avoiding rereading inode size repeatedly unnecessarily) to make it clearer. Cc: stable@vger.kernel.org Fixes: 7fe6fe95b936 ("cifs: add FALLOC_FL_INSERT_RANGE support") Signed-off-by: David Howells cc: Ronnie Sahlberg Signed-off-by: Steve French --- fs/cifs/smb2ops.c | 24 ++++++++++++++++-------- 1 file changed, 16 insertions(+), 8 deletions(-) diff --git a/fs/cifs/smb2ops.c b/fs/cifs/smb2ops.c index 5b5ddc1..7c941ce 100644 --- a/fs/cifs/smb2ops.c +++ b/fs/cifs/smb2ops.c @@ -3722,35 +3722,43 @@ static long smb3_insert_range(struct file *file, struct cifs_tcon *tcon, struct cifsFileInfo *cfile = file->private_data; struct inode *inode = file_inode(file); __le64 eof; - __u64 count; + __u64 count, old_eof; xid = get_xid(); - if (off >= i_size_read(inode)) { + inode_lock(inode); + + old_eof = i_size_read(inode); + if (off >= old_eof) { rc = -EINVAL; goto out; } - count = i_size_read(inode) - off; - eof = cpu_to_le64(i_size_read(inode) + len); + count = old_eof - off; + eof = cpu_to_le64(old_eof + len); + filemap_invalidate_lock(inode->i_mapping); filemap_write_and_wait(inode->i_mapping); + truncate_pagecache_range(inode, off, old_eof); rc = SMB2_set_eof(xid, tcon, cfile->fid.persistent_fid, cfile->fid.volatile_fid, cfile->pid, &eof); if (rc < 0) - goto out; + goto out_2; rc = smb2_copychunk_range(xid, cfile, cfile, off, count, off + len); if (rc < 0) - goto out; + goto out_2; - rc = smb3_zero_range(file, tcon, off, len, 1); + rc = smb3_zero_data(file, tcon, off, len, xid); if (rc < 0) - goto out; + goto out_2; rc = 0; +out_2: + filemap_invalidate_unlock(inode->i_mapping); out: + inode_unlock(inode); free_xid(xid); return rc; } -- 2.7.4