Update Linux to v5.4.2
Change-Id: Idf6911045d9d382da2cfe01b1edff026404ac8fd
diff --git a/fs/overlayfs/copy_up.c b/fs/overlayfs/copy_up.c
index 1cc797a..b801c63 100644
--- a/fs/overlayfs/copy_up.c
+++ b/fs/overlayfs/copy_up.c
@@ -1,10 +1,7 @@
+// SPDX-License-Identifier: GPL-2.0-only
/*
*
* Copyright (C) 2011 Novell 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/module.h>
@@ -37,7 +34,7 @@
}
module_param_call(check_copy_up, ovl_ccup_set, ovl_ccup_get, NULL, 0644);
-MODULE_PARM_DESC(ovl_check_copy_up, "Obsolete; does nothing");
+MODULE_PARM_DESC(check_copy_up, "Obsolete; does nothing");
int ovl_copy_xattr(struct dentry *old, struct dentry *new)
{
@@ -125,6 +122,7 @@
struct file *new_file;
loff_t old_pos = 0;
loff_t new_pos = 0;
+ loff_t cloned;
int error = 0;
if (len == 0)
@@ -141,11 +139,10 @@
}
/* Try to use clone_file_range to clone up within the same fs */
- error = do_clone_file_range(old_file, 0, new_file, 0, len);
- if (!error)
+ cloned = do_clone_file_range(old_file, 0, new_file, 0, len, 0);
+ if (cloned == len)
goto out;
/* Couldn't clone, so now we try to copy the data */
- error = 0;
/* FIXME: copy up sparse files efficiently */
while (len) {
@@ -395,7 +392,6 @@
struct dentry *destdir;
struct qstr destname;
struct dentry *workdir;
- bool tmpfile;
bool origin;
bool indexed;
bool metacopy;
@@ -440,67 +436,28 @@
return err;
}
-static int ovl_install_temp(struct ovl_copy_up_ctx *c, struct dentry *temp,
- struct dentry **newdentry)
-{
- int err;
- struct dentry *upper;
- struct inode *udir = d_inode(c->destdir);
-
- upper = lookup_one_len(c->destname.name, c->destdir, c->destname.len);
- if (IS_ERR(upper))
- return PTR_ERR(upper);
-
- if (c->tmpfile)
- err = ovl_do_link(temp, udir, upper);
- else
- err = ovl_do_rename(d_inode(c->workdir), temp, udir, upper, 0);
-
- if (!err)
- *newdentry = dget(c->tmpfile ? upper : temp);
- dput(upper);
-
- return err;
-}
-
-static struct dentry *ovl_get_tmpfile(struct ovl_copy_up_ctx *c)
-{
- int err;
- struct dentry *temp;
- const struct cred *old_creds = NULL;
- struct cred *new_creds = NULL;
- struct ovl_cattr cattr = {
- /* Can't properly set mode on creation because of the umask */
- .mode = c->stat.mode & S_IFMT,
- .rdev = c->stat.rdev,
- .link = c->link
- };
-
- err = security_inode_copy_up(c->dentry, &new_creds);
- temp = ERR_PTR(err);
- if (err < 0)
- goto out;
-
- if (new_creds)
- old_creds = override_creds(new_creds);
-
- if (c->tmpfile)
- temp = ovl_do_tmpfile(c->workdir, c->stat.mode);
- else
- temp = ovl_create_temp(c->workdir, &cattr);
-out:
- if (new_creds) {
- revert_creds(old_creds);
- put_cred(new_creds);
- }
-
- return temp;
-}
-
static int ovl_copy_up_inode(struct ovl_copy_up_ctx *c, struct dentry *temp)
{
int err;
+ /*
+ * Copy up data first and then xattrs. Writing data after
+ * xattrs will remove security.capability xattr automatically.
+ */
+ if (S_ISREG(c->stat.mode) && !c->metacopy) {
+ struct path upperpath, datapath;
+
+ ovl_path_upper(c->dentry, &upperpath);
+ if (WARN_ON(upperpath.dentry != NULL))
+ return -EIO;
+ upperpath.dentry = temp;
+
+ ovl_path_lowerdata(c->dentry, &datapath);
+ err = ovl_copy_up_data(&datapath, &upperpath, c->stat.size);
+ if (err)
+ return err;
+ }
+
err = ovl_copy_xattr(c->lowerpath.dentry, temp);
if (err)
return err;
@@ -518,19 +475,6 @@
return err;
}
- if (S_ISREG(c->stat.mode) && !c->metacopy) {
- struct path upperpath, datapath;
-
- ovl_path_upper(c->dentry, &upperpath);
- BUG_ON(upperpath.dentry != NULL);
- upperpath.dentry = temp;
-
- ovl_path_lowerdata(c->dentry, &datapath);
- err = ovl_copy_up_data(&datapath, &upperpath, c->stat.size);
- if (err)
- return err;
- }
-
if (c->metacopy) {
err = ovl_check_setxattr(c->dentry, temp, OVL_XATTR_METACOPY,
NULL, 0, -EOPNOTSUPP);
@@ -548,51 +492,148 @@
return err;
}
-static int ovl_copy_up_locked(struct ovl_copy_up_ctx *c)
+struct ovl_cu_creds {
+ const struct cred *old;
+ struct cred *new;
+};
+
+static int ovl_prep_cu_creds(struct dentry *dentry, struct ovl_cu_creds *cc)
{
- struct inode *udir = c->destdir->d_inode;
- struct inode *inode;
- struct dentry *newdentry = NULL;
- struct dentry *temp;
int err;
- temp = ovl_get_tmpfile(c);
+ cc->old = cc->new = NULL;
+ err = security_inode_copy_up(dentry, &cc->new);
+ if (err < 0)
+ return err;
+
+ if (cc->new)
+ cc->old = override_creds(cc->new);
+
+ return 0;
+}
+
+static void ovl_revert_cu_creds(struct ovl_cu_creds *cc)
+{
+ if (cc->new) {
+ revert_creds(cc->old);
+ put_cred(cc->new);
+ }
+}
+
+/*
+ * Copyup using workdir to prepare temp file. Used when copying up directories,
+ * special files or when upper fs doesn't support O_TMPFILE.
+ */
+static int ovl_copy_up_workdir(struct ovl_copy_up_ctx *c)
+{
+ struct inode *inode;
+ struct inode *udir = d_inode(c->destdir), *wdir = d_inode(c->workdir);
+ struct dentry *temp, *upper;
+ struct ovl_cu_creds cc;
+ int err;
+ struct ovl_cattr cattr = {
+ /* Can't properly set mode on creation because of the umask */
+ .mode = c->stat.mode & S_IFMT,
+ .rdev = c->stat.rdev,
+ .link = c->link
+ };
+
+ err = ovl_lock_rename_workdir(c->workdir, c->destdir);
+ if (err)
+ return err;
+
+ err = ovl_prep_cu_creds(c->dentry, &cc);
+ if (err)
+ goto unlock;
+
+ temp = ovl_create_temp(c->workdir, &cattr);
+ ovl_revert_cu_creds(&cc);
+
+ err = PTR_ERR(temp);
+ if (IS_ERR(temp))
+ goto unlock;
+
+ err = ovl_copy_up_inode(c, temp);
+ if (err)
+ goto cleanup;
+
+ if (S_ISDIR(c->stat.mode) && c->indexed) {
+ err = ovl_create_index(c->dentry, c->lowerpath.dentry, temp);
+ if (err)
+ goto cleanup;
+ }
+
+ upper = lookup_one_len(c->destname.name, c->destdir, c->destname.len);
+ err = PTR_ERR(upper);
+ if (IS_ERR(upper))
+ goto cleanup;
+
+ err = ovl_do_rename(wdir, temp, udir, upper, 0);
+ dput(upper);
+ if (err)
+ goto cleanup;
+
+ if (!c->metacopy)
+ ovl_set_upperdata(d_inode(c->dentry));
+ inode = d_inode(c->dentry);
+ ovl_inode_update(inode, temp);
+ if (S_ISDIR(inode->i_mode))
+ ovl_set_flag(OVL_WHITEOUTS, inode);
+unlock:
+ unlock_rename(c->workdir, c->destdir);
+
+ return err;
+
+cleanup:
+ ovl_cleanup(wdir, temp);
+ dput(temp);
+ goto unlock;
+}
+
+/* Copyup using O_TMPFILE which does not require cross dir locking */
+static int ovl_copy_up_tmpfile(struct ovl_copy_up_ctx *c)
+{
+ struct inode *udir = d_inode(c->destdir);
+ struct dentry *temp, *upper;
+ struct ovl_cu_creds cc;
+ int err;
+
+ err = ovl_prep_cu_creds(c->dentry, &cc);
+ if (err)
+ return err;
+
+ temp = ovl_do_tmpfile(c->workdir, c->stat.mode);
+ ovl_revert_cu_creds(&cc);
+
if (IS_ERR(temp))
return PTR_ERR(temp);
err = ovl_copy_up_inode(c, temp);
if (err)
- goto out;
+ goto out_dput;
- if (S_ISDIR(c->stat.mode) && c->indexed) {
- err = ovl_create_index(c->dentry, c->lowerpath.dentry, temp);
- if (err)
- goto out;
- }
+ inode_lock_nested(udir, I_MUTEX_PARENT);
- if (c->tmpfile) {
- inode_lock_nested(udir, I_MUTEX_PARENT);
- err = ovl_install_temp(c, temp, &newdentry);
- inode_unlock(udir);
- } else {
- err = ovl_install_temp(c, temp, &newdentry);
+ upper = lookup_one_len(c->destname.name, c->destdir, c->destname.len);
+ err = PTR_ERR(upper);
+ if (!IS_ERR(upper)) {
+ err = ovl_do_link(temp, udir, upper);
+ dput(upper);
}
+ inode_unlock(udir);
+
if (err)
- goto out;
+ goto out_dput;
if (!c->metacopy)
ovl_set_upperdata(d_inode(c->dentry));
- inode = d_inode(c->dentry);
- ovl_inode_update(inode, newdentry);
- if (S_ISDIR(inode->i_mode))
- ovl_set_flag(OVL_WHITEOUTS, inode);
+ ovl_inode_update(d_inode(c->dentry), temp);
-out:
- if (err && !c->tmpfile)
- ovl_cleanup(d_inode(c->workdir), temp);
+ return 0;
+
+out_dput:
dput(temp);
return err;
-
}
/*
@@ -646,18 +687,10 @@
}
/* Should we copyup with O_TMPFILE or with workdir? */
- if (S_ISREG(c->stat.mode) && ofs->tmpfile) {
- c->tmpfile = true;
- err = ovl_copy_up_locked(c);
- } else {
- err = ovl_lock_rename_workdir(c->workdir, c->destdir);
- if (!err) {
- err = ovl_copy_up_locked(c);
- unlock_rename(c->workdir, c->destdir);
- }
- }
-
-
+ if (S_ISREG(c->stat.mode) && ofs->tmpfile)
+ err = ovl_copy_up_tmpfile(c);
+ else
+ err = ovl_copy_up_workdir(c);
if (err)
goto out;
@@ -706,6 +739,8 @@
{
struct path upperpath, datapath;
int err;
+ char *capability = NULL;
+ ssize_t uninitialized_var(cap_size);
ovl_path_upper(c->dentry, &upperpath);
if (WARN_ON(upperpath.dentry == NULL))
@@ -715,15 +750,37 @@
if (WARN_ON(datapath.dentry == NULL))
return -EIO;
+ if (c->stat.size) {
+ err = cap_size = ovl_getxattr(upperpath.dentry, XATTR_NAME_CAPS,
+ &capability, 0);
+ if (err < 0 && err != -ENODATA)
+ goto out;
+ }
+
err = ovl_copy_up_data(&datapath, &upperpath, c->stat.size);
if (err)
- return err;
+ goto out_free;
+
+ /*
+ * Writing to upper file will clear security.capability xattr. We
+ * don't want that to happen for normal copy-up operation.
+ */
+ if (capability) {
+ err = ovl_do_setxattr(upperpath.dentry, XATTR_NAME_CAPS,
+ capability, cap_size, 0);
+ if (err)
+ goto out_free;
+ }
+
err = vfs_removexattr(upperpath.dentry, OVL_XATTR_METACOPY);
if (err)
- return err;
+ goto out_free;
ovl_set_upperdata(d_inode(c->dentry));
+out_free:
+ kfree(capability);
+out:
return err;
}
@@ -849,14 +906,14 @@
return true;
}
-int ovl_open_maybe_copy_up(struct dentry *dentry, unsigned int file_flags)
+int ovl_maybe_copy_up(struct dentry *dentry, int flags)
{
int err = 0;
- if (ovl_open_need_copy_up(dentry, file_flags)) {
+ if (ovl_open_need_copy_up(dentry, flags)) {
err = ovl_want_write(dentry);
if (!err) {
- err = ovl_copy_up_flags(dentry, file_flags);
+ err = ovl_copy_up_flags(dentry, flags);
ovl_drop_write(dentry);
}
}