From cfe5e3905201349e9cf3f95d52ff4bd100bde37d Mon Sep 17 00:00:00 2001 From: Daniel Baumann Date: Sun, 14 Apr 2024 21:10:49 +0200 Subject: Adding upstream version 2.39.3. Signed-off-by: Daniel Baumann --- libmount/src/hook_mkdir.c | 139 ++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 139 insertions(+) create mode 100644 libmount/src/hook_mkdir.c (limited to 'libmount/src/hook_mkdir.c') diff --git a/libmount/src/hook_mkdir.c b/libmount/src/hook_mkdir.c new file mode 100644 index 0000000..da9c407 --- /dev/null +++ b/libmount/src/hook_mkdir.c @@ -0,0 +1,139 @@ +/* SPDX-License-Identifier: LGPL-2.1-or-later */ +/* + * This file is part of libmount from util-linux project. + * + * Copyright (C) 2022 Karel Zak + * + * libmount is free software; you can redistribute it and/or modify it + * under the terms of the GNU Lesser General Public License as published by + * the Free Software Foundation; either version 2.1 of the License, or + * (at your option) any later version. + * + * + * Please, see the comment in libmount/src/hooks.c to understand how hooks work. + */ +#include "mountP.h" +#include "fileutils.h" + +static int hookset_deinit(struct libmnt_context *cxt, const struct libmnt_hookset *hs) +{ + void *data = NULL; + + DBG(HOOK, ul_debugobj(hs, "deinit '%s'", hs->name)); + + /* remove all our hooks and free hook data */ + while (mnt_context_remove_hook(cxt, hs, 0, &data) == 0) { + if (data) + free(data); + data = NULL; + } + + return 0; +} + +static int is_mkdir_required(struct libmnt_context *cxt, const char *tgt, mode_t *mode, int *rc) +{ + struct libmnt_optlist *ol; + struct libmnt_opt *opt; + const char *mstr = NULL; + + assert(cxt); + assert(cxt->map_userspace); + assert(tgt); + assert(mode); + assert(rc); + + *mode = 0; + *rc = 0; + + ol = mnt_context_get_optlist(cxt); + if (!ol) + return -ENOMEM; + + opt = mnt_optlist_get_named(ol, "X-mount.mkdir", cxt->map_userspace); + if (!opt) + opt = mnt_optlist_get_named(ol, "x-mount.mkdir", cxt->map_userspace); + if (!opt) + return 0; + + if (mnt_is_path(tgt)) + return 0; + + mstr = mnt_opt_get_value(opt); + + if (mstr && *mstr) { + char *end = NULL; + + if (*mstr == '"') + mstr++; + + errno = 0; + *mode = strtol(mstr, &end, 8); + + if (errno || !end || !(*end == '"' || *end == '\0')) { + DBG(HOOK, ul_debug("failed to parse mkdir mode '%s'", mstr)); + *rc = -MNT_ERR_MOUNTOPT; + return 0; + } + } + + if (!*mode) + *mode = S_IRWXU | /* 0755 */ + S_IRGRP | S_IXGRP | + S_IROTH | S_IXOTH; + + DBG(HOOK, ul_debug("mkdir %s (%o) wanted", tgt, *mode)); + + return 1; +} + +static int hook_prepare_target( + struct libmnt_context *cxt, + const struct libmnt_hookset *hs, + void *data __attribute__((__unused__))) +{ + int rc = 0; + mode_t mode = 0; + const char *tgt; + + assert(cxt); + + tgt = mnt_fs_get_target(cxt->fs); + if (!tgt) + return 0; + + if (cxt->action == MNT_ACT_MOUNT + && is_mkdir_required(cxt, tgt, &mode, &rc)) { + + struct libmnt_cache *cache; + + /* supported only for root or non-suid mount(8) */ + if (!mnt_context_is_restricted(cxt)) { + rc = ul_mkdir_p(tgt, mode); + if (rc) + DBG(HOOK, ul_debugobj(hs, "mkdir %s failed: %m", tgt)); + } else + rc = -EPERM; + + if (rc == 0) { + cache = mnt_context_get_cache(cxt); + if (cache) { + char *path = mnt_resolve_path(tgt, cache); + if (path && strcmp(path, tgt) != 0) + rc = mnt_fs_set_target(cxt->fs, path); + } + } + } + + return rc; +} + +const struct libmnt_hookset hookset_mkdir = +{ + .name = "__mkdir", + + .firststage = MNT_STAGE_PREP_TARGET, + .firstcall = hook_prepare_target, + + .deinit = hookset_deinit +}; -- cgit v1.2.3