smb3: missing inode locks in zero range

smb3 fallocate zero range was not grabbing the inode or filemap_invalidate
locks so could have race with pagemap reinstantiating the page.

Cc: stable@vger.kernel.org
Signed-off-by: David Howells <dhowells@redhat.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
This commit is contained in:
David Howells 2022-08-23 01:01:36 -05:00 committed by Steve French
parent 1c23f9e627
commit c919c164fc

View File

@ -3307,26 +3307,43 @@ get_smb2_acl(struct cifs_sb_info *cifs_sb,
return pntsd;
}
static long smb3_zero_data(struct file *file, struct cifs_tcon *tcon,
loff_t offset, loff_t len, unsigned int xid)
{
struct cifsFileInfo *cfile = file->private_data;
struct file_zero_data_information fsctl_buf;
cifs_dbg(FYI, "Offset %lld len %lld\n", offset, len);
fsctl_buf.FileOffset = cpu_to_le64(offset);
fsctl_buf.BeyondFinalZero = cpu_to_le64(offset + len);
return SMB2_ioctl(xid, tcon, cfile->fid.persistent_fid,
cfile->fid.volatile_fid, FSCTL_SET_ZERO_DATA,
(char *)&fsctl_buf,
sizeof(struct file_zero_data_information),
0, NULL, NULL);
}
static long smb3_zero_range(struct file *file, struct cifs_tcon *tcon,
loff_t offset, loff_t len, bool keep_size)
{
struct cifs_ses *ses = tcon->ses;
struct inode *inode;
struct cifsInodeInfo *cifsi;
struct inode *inode = file_inode(file);
struct cifsInodeInfo *cifsi = CIFS_I(inode);
struct cifsFileInfo *cfile = file->private_data;
struct file_zero_data_information fsctl_buf;
long rc;
unsigned int xid;
__le64 eof;
xid = get_xid();
inode = d_inode(cfile->dentry);
cifsi = CIFS_I(inode);
trace_smb3_zero_enter(xid, cfile->fid.persistent_fid, tcon->tid,
ses->Suid, offset, len);
inode_lock(inode);
filemap_invalidate_lock(inode->i_mapping);
/*
* We zero the range through ioctl, so we need remove the page caches
* first, otherwise the data may be inconsistent with the server.
@ -3334,26 +3351,12 @@ static long smb3_zero_range(struct file *file, struct cifs_tcon *tcon,
truncate_pagecache_range(inode, offset, offset + len - 1);
/* if file not oplocked can't be sure whether asking to extend size */
if (!CIFS_CACHE_READ(cifsi))
if (keep_size == false) {
rc = -EOPNOTSUPP;
trace_smb3_zero_err(xid, cfile->fid.persistent_fid,
tcon->tid, ses->Suid, offset, len, rc);
free_xid(xid);
return rc;
}
rc = -EOPNOTSUPP;
if (keep_size == false && !CIFS_CACHE_READ(cifsi))
goto zero_range_exit;
cifs_dbg(FYI, "Offset %lld len %lld\n", offset, len);
fsctl_buf.FileOffset = cpu_to_le64(offset);
fsctl_buf.BeyondFinalZero = cpu_to_le64(offset + len);
rc = SMB2_ioctl(xid, tcon, cfile->fid.persistent_fid,
cfile->fid.volatile_fid, FSCTL_SET_ZERO_DATA,
(char *)&fsctl_buf,
sizeof(struct file_zero_data_information),
0, NULL, NULL);
if (rc)
rc = smb3_zero_data(file, tcon, offset, len, xid);
if (rc < 0)
goto zero_range_exit;
/*
@ -3366,6 +3369,8 @@ static long smb3_zero_range(struct file *file, struct cifs_tcon *tcon,
}
zero_range_exit:
filemap_invalidate_unlock(inode->i_mapping);
inode_unlock(inode);
free_xid(xid);
if (rc)
trace_smb3_zero_err(xid, cfile->fid.persistent_fid, tcon->tid,