Update Linux to v5.4.2
Change-Id: Idf6911045d9d382da2cfe01b1edff026404ac8fd
diff --git a/fs/overlayfs/file.c b/fs/overlayfs/file.c
index 986313d..e235a63 100644
--- a/fs/overlayfs/file.c
+++ b/fs/overlayfs/file.c
@@ -1,9 +1,6 @@
+// SPDX-License-Identifier: GPL-2.0-only
/*
* Copyright (C) 2017 Red Hat, Inc.
- *
- * This program is free software; you can redistribute it and/or modify it
- * under the terms of the GNU General Public License version 2 as published by
- * the Free Software Foundation.
*/
#include <linux/cred.h>
@@ -11,6 +8,7 @@
#include <linux/mount.h>
#include <linux/xattr.h>
#include <linux/uio.h>
+#include <linux/uaccess.h>
#include "overlayfs.h"
static char ovl_whatisit(struct inode *inode, struct inode *realinode)
@@ -29,10 +27,11 @@
struct inode *inode = file_inode(file);
struct file *realfile;
const struct cred *old_cred;
+ int flags = file->f_flags | O_NOATIME | FMODE_NONOTIFY;
old_cred = ovl_override_creds(inode->i_sb);
- realfile = open_with_fake_path(&file->f_path, file->f_flags | O_NOATIME,
- realinode, current_cred());
+ realfile = open_with_fake_path(&file->f_path, flags, realinode,
+ current_cred());
revert_creds(old_cred);
pr_debug("open(%p[%pD2/%c], 0%o) -> (%p, 0%o)\n",
@@ -50,7 +49,7 @@
int err;
/* No atime modificaton on underlying */
- flags |= O_NOATIME;
+ flags |= O_NOATIME | FMODE_NONOTIFY;
/* If some flag changed that cannot be changed then something's amiss */
if (WARN_ON((file->f_flags ^ flags) & ~OVL_SETFL_MASK))
@@ -116,11 +115,10 @@
static int ovl_open(struct inode *inode, struct file *file)
{
- struct dentry *dentry = file_dentry(file);
struct file *realfile;
int err;
- err = ovl_open_maybe_copy_up(dentry, file->f_flags);
+ err = ovl_maybe_copy_up(file_dentry(file), file->f_flags);
if (err)
return err;
@@ -145,11 +143,47 @@
static loff_t ovl_llseek(struct file *file, loff_t offset, int whence)
{
- struct inode *realinode = ovl_inode_real(file_inode(file));
+ struct inode *inode = file_inode(file);
+ struct fd real;
+ const struct cred *old_cred;
+ ssize_t ret;
- return generic_file_llseek_size(file, offset, whence,
- realinode->i_sb->s_maxbytes,
- i_size_read(realinode));
+ /*
+ * The two special cases below do not need to involve real fs,
+ * so we can optimizing concurrent callers.
+ */
+ if (offset == 0) {
+ if (whence == SEEK_CUR)
+ return file->f_pos;
+
+ if (whence == SEEK_SET)
+ return vfs_setpos(file, 0, 0);
+ }
+
+ ret = ovl_real_fdget(file, &real);
+ if (ret)
+ return ret;
+
+ /*
+ * Overlay file f_pos is the master copy that is preserved
+ * through copy up and modified on read/write, but only real
+ * fs knows how to SEEK_HOLE/SEEK_DATA and real fs may impose
+ * limitations that are more strict than ->s_maxbytes for specific
+ * files, so we use the real file to perform seeks.
+ */
+ inode_lock(inode);
+ real.file->f_pos = file->f_pos;
+
+ old_cred = ovl_override_creds(inode->i_sb);
+ ret = vfs_llseek(real.file, offset, whence);
+ revert_creds(old_cred);
+
+ file->f_pos = real.file->f_pos;
+ inode_unlock(inode);
+
+ fdput(real);
+
+ return ret;
}
static void ovl_file_accessed(struct file *file)
@@ -372,34 +406,118 @@
return ret;
}
-static long ovl_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
+static long ovl_ioctl_set_flags(struct file *file, unsigned int cmd,
+ unsigned long arg, unsigned int iflags)
{
long ret;
struct inode *inode = file_inode(file);
+ unsigned int old_iflags;
+
+ if (!inode_owner_or_capable(inode))
+ return -EACCES;
+
+ ret = mnt_want_write_file(file);
+ if (ret)
+ return ret;
+
+ inode_lock(inode);
+
+ /* Check the capability before cred override */
+ ret = -EPERM;
+ old_iflags = READ_ONCE(inode->i_flags);
+ if (((iflags ^ old_iflags) & (S_APPEND | S_IMMUTABLE)) &&
+ !capable(CAP_LINUX_IMMUTABLE))
+ goto unlock;
+
+ ret = ovl_maybe_copy_up(file_dentry(file), O_WRONLY);
+ if (ret)
+ goto unlock;
+
+ ret = ovl_real_ioctl(file, cmd, arg);
+
+ ovl_copyflags(ovl_inode_real(inode), inode);
+unlock:
+ inode_unlock(inode);
+
+ mnt_drop_write_file(file);
+
+ return ret;
+
+}
+
+static unsigned int ovl_fsflags_to_iflags(unsigned int flags)
+{
+ unsigned int iflags = 0;
+
+ if (flags & FS_SYNC_FL)
+ iflags |= S_SYNC;
+ if (flags & FS_APPEND_FL)
+ iflags |= S_APPEND;
+ if (flags & FS_IMMUTABLE_FL)
+ iflags |= S_IMMUTABLE;
+ if (flags & FS_NOATIME_FL)
+ iflags |= S_NOATIME;
+
+ return iflags;
+}
+
+static long ovl_ioctl_set_fsflags(struct file *file, unsigned int cmd,
+ unsigned long arg)
+{
+ unsigned int flags;
+
+ if (get_user(flags, (int __user *) arg))
+ return -EFAULT;
+
+ return ovl_ioctl_set_flags(file, cmd, arg,
+ ovl_fsflags_to_iflags(flags));
+}
+
+static unsigned int ovl_fsxflags_to_iflags(unsigned int xflags)
+{
+ unsigned int iflags = 0;
+
+ if (xflags & FS_XFLAG_SYNC)
+ iflags |= S_SYNC;
+ if (xflags & FS_XFLAG_APPEND)
+ iflags |= S_APPEND;
+ if (xflags & FS_XFLAG_IMMUTABLE)
+ iflags |= S_IMMUTABLE;
+ if (xflags & FS_XFLAG_NOATIME)
+ iflags |= S_NOATIME;
+
+ return iflags;
+}
+
+static long ovl_ioctl_set_fsxflags(struct file *file, unsigned int cmd,
+ unsigned long arg)
+{
+ struct fsxattr fa;
+
+ memset(&fa, 0, sizeof(fa));
+ if (copy_from_user(&fa, (void __user *) arg, sizeof(fa)))
+ return -EFAULT;
+
+ return ovl_ioctl_set_flags(file, cmd, arg,
+ ovl_fsxflags_to_iflags(fa.fsx_xflags));
+}
+
+static long ovl_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
+{
+ long ret;
switch (cmd) {
case FS_IOC_GETFLAGS:
+ case FS_IOC_FSGETXATTR:
ret = ovl_real_ioctl(file, cmd, arg);
break;
case FS_IOC_SETFLAGS:
- if (!inode_owner_or_capable(inode))
- return -EACCES;
+ ret = ovl_ioctl_set_fsflags(file, cmd, arg);
+ break;
- ret = mnt_want_write_file(file);
- if (ret)
- return ret;
-
- ret = ovl_copy_up_with_data(file_dentry(file));
- if (!ret) {
- ret = ovl_real_ioctl(file, cmd, arg);
-
- inode_lock(inode);
- ovl_copyflags(ovl_inode_real(inode), inode);
- inode_unlock(inode);
- }
-
- mnt_drop_write_file(file);
+ case FS_IOC_FSSETXATTR:
+ ret = ovl_ioctl_set_fsxflags(file, cmd, arg);
break;
default:
@@ -434,14 +552,14 @@
OVL_DEDUPE,
};
-static ssize_t ovl_copyfile(struct file *file_in, loff_t pos_in,
+static loff_t ovl_copyfile(struct file *file_in, loff_t pos_in,
struct file *file_out, loff_t pos_out,
- u64 len, unsigned int flags, enum ovl_copyop op)
+ loff_t len, unsigned int flags, enum ovl_copyop op)
{
struct inode *inode_out = file_inode(file_out);
struct fd real_in, real_out;
const struct cred *old_cred;
- ssize_t ret;
+ loff_t ret;
ret = ovl_real_fdget(file_out, &real_out);
if (ret)
@@ -462,12 +580,13 @@
case OVL_CLONE:
ret = vfs_clone_file_range(real_in.file, pos_in,
- real_out.file, pos_out, len);
+ real_out.file, pos_out, len, flags);
break;
case OVL_DEDUPE:
ret = vfs_dedupe_file_range_one(real_in.file, pos_in,
- real_out.file, pos_out, len);
+ real_out.file, pos_out, len,
+ flags);
break;
}
revert_creds(old_cred);
@@ -489,26 +608,31 @@
OVL_COPY);
}
-static int ovl_clone_file_range(struct file *file_in, loff_t pos_in,
- struct file *file_out, loff_t pos_out, u64 len)
+static loff_t ovl_remap_file_range(struct file *file_in, loff_t pos_in,
+ struct file *file_out, loff_t pos_out,
+ loff_t len, unsigned int remap_flags)
{
- return ovl_copyfile(file_in, pos_in, file_out, pos_out, len, 0,
- OVL_CLONE);
-}
+ enum ovl_copyop op;
-static int ovl_dedupe_file_range(struct file *file_in, loff_t pos_in,
- struct file *file_out, loff_t pos_out, u64 len)
-{
+ if (remap_flags & ~(REMAP_FILE_DEDUP | REMAP_FILE_ADVISORY))
+ return -EINVAL;
+
+ if (remap_flags & REMAP_FILE_DEDUP)
+ op = OVL_DEDUPE;
+ else
+ op = OVL_CLONE;
+
/*
* Don't copy up because of a dedupe request, this wouldn't make sense
* most of the time (data would be duplicated instead of deduplicated).
*/
- if (!ovl_inode_upper(file_inode(file_in)) ||
- !ovl_inode_upper(file_inode(file_out)))
+ if (op == OVL_DEDUPE &&
+ (!ovl_inode_upper(file_inode(file_in)) ||
+ !ovl_inode_upper(file_inode(file_out))))
return -EPERM;
- return ovl_copyfile(file_in, pos_in, file_out, pos_out, len, 0,
- OVL_DEDUPE);
+ return ovl_copyfile(file_in, pos_in, file_out, pos_out, len,
+ remap_flags, op);
}
const struct file_operations ovl_file_operations = {
@@ -525,6 +649,5 @@
.compat_ioctl = ovl_compat_ioctl,
.copy_file_range = ovl_copy_file_range,
- .clone_file_range = ovl_clone_file_range,
- .dedupe_file_range = ovl_dedupe_file_range,
+ .remap_file_range = ovl_remap_file_range,
};