The patch below does not apply to the 5.19-stable tree. If someone wants it applied there, or to any other stable or longterm tree, then please email the backport, including the original git commit id to stable@vger.kernel.org.
thanks,
greg k-h
------------------ original commit in Linus's tree ------------------
From 9c8b7a293f50253e694f19161c045817a938e551 Mon Sep 17 00:00:00 2001 From: David Howells dhowells@redhat.com 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 dhowells@redhat.com cc: Ronnie Sahlberg lsahlber@redhat.com Signed-off-by: Steve French stfrench@microsoft.com
diff --git a/fs/cifs/smb2ops.c b/fs/cifs/smb2ops.c index 5b5ddc1b4638..7c941ce1e7a9 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; }