diff options
| -rw-r--r-- | fs/overlayfs/copy_up.c | 64 |
1 files changed, 31 insertions, 33 deletions
diff --git a/fs/overlayfs/copy_up.c b/fs/overlayfs/copy_up.c index 859e75daff8e..758611ee4475 100644 --- a/fs/overlayfs/copy_up.c +++ b/fs/overlayfs/copy_up.c @@ -724,34 +724,33 @@ static int ovl_copy_up_metadata(struct ovl_copy_up_ctx *c, struct dentry *temp) return err; } -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) +static const struct cred *ovl_prepare_copy_up_creds(struct dentry *dentry) { + struct cred *copy_up_cred = NULL; int err; - cc->old = cc->new = NULL; - err = security_inode_copy_up(dentry, &cc->new); + err = security_inode_copy_up(dentry, ©_up_cred); if (err < 0) - return err; + return ERR_PTR(err); - if (cc->new) - cc->old = override_creds(cc->new); + if (!copy_up_cred) + return NULL; - return 0; + return override_creds(copy_up_cred); } -static void ovl_revert_cu_creds(struct ovl_cu_creds *cc) +static void ovl_revert_copy_up_creds(const struct cred *orig_cred) { - if (cc->new) { - revert_creds(cc->old); - put_cred(cc->new); - } + const struct cred *copy_up_cred; + + copy_up_cred = revert_creds(orig_cred); + put_cred(copy_up_cred); } +DEFINE_CLASS(copy_up_creds, const struct cred *, + if (!IS_ERR_OR_NULL(_T)) ovl_revert_copy_up_creds(_T), + ovl_prepare_copy_up_creds(dentry), struct dentry *dentry) + /* * Copyup using workdir to prepare temp file. Used when copying up directories, * special files or when upper fs doesn't support O_TMPFILE. @@ -763,7 +762,6 @@ static int ovl_copy_up_workdir(struct ovl_copy_up_ctx *c) struct path path = { .mnt = ovl_upper_mnt(ofs) }; struct renamedata rd = {}; struct dentry *temp; - struct ovl_cu_creds cc; int err; struct ovl_cattr cattr = { /* Can't properly set mode on creation because of the umask */ @@ -772,14 +770,14 @@ static int ovl_copy_up_workdir(struct ovl_copy_up_ctx *c) .link = c->link }; - err = ovl_prep_cu_creds(c->dentry, &cc); - if (err) - return err; + scoped_class(copy_up_creds, copy_up_creds, c->dentry) { + if (IS_ERR(copy_up_creds)) + return PTR_ERR(copy_up_creds); - ovl_start_write(c->dentry); - temp = ovl_create_temp(ofs, c->workdir, &cattr); - ovl_end_write(c->dentry); - ovl_revert_cu_creds(&cc); + ovl_start_write(c->dentry); + temp = ovl_create_temp(ofs, c->workdir, &cattr); + ovl_end_write(c->dentry); + } if (IS_ERR(temp)) return PTR_ERR(temp); @@ -857,17 +855,17 @@ static int ovl_copy_up_tmpfile(struct ovl_copy_up_ctx *c) struct inode *udir = d_inode(c->destdir); struct dentry *temp, *upper; struct file *tmpfile; - struct ovl_cu_creds cc; int err; - err = ovl_prep_cu_creds(c->dentry, &cc); - if (err) - return err; + scoped_class(copy_up_creds, copy_up_creds, c->dentry) { + if (IS_ERR(copy_up_creds)) + return PTR_ERR(copy_up_creds); + + ovl_start_write(c->dentry); + tmpfile = ovl_do_tmpfile(ofs, c->workdir, c->stat.mode); + ovl_end_write(c->dentry); + } - ovl_start_write(c->dentry); - tmpfile = ovl_do_tmpfile(ofs, c->workdir, c->stat.mode); - ovl_end_write(c->dentry); - ovl_revert_cu_creds(&cc); if (IS_ERR(tmpfile)) return PTR_ERR(tmpfile); |