zfs_ioc_snapshot: check user-prop permissions on snapshotted datasets

Previously, the permissions were checked on the pool which was obviously
incorrect.

After this change, zfs_check_userprops() only validates the properties
without any permission checks.  The permissions are checked individually
for each snapshotted dataset.

This was also committed to ZoL: zfsonlinux/zfs@e6203d2

Reported by:	CyberSecure
MFC after:	1 week
Sponsored by:	CyberSecure
This commit is contained in:
avg 2019-08-29 07:19:06 +00:00
parent dc45f45b15
commit 3dd6b8e5c7

View File

@ -2747,10 +2747,9 @@ zfs_set_prop_nvlist(const char *dsname, zprop_source_t source, nvlist_t *nvl,
* Check that all the properties are valid user properties.
*/
static int
zfs_check_userprops(const char *fsname, nvlist_t *nvl)
zfs_check_userprops(nvlist_t *nvl)
{
nvpair_t *pair = NULL;
int error = 0;
while ((pair = nvlist_next_nvpair(nvl, pair)) != NULL) {
const char *propname = nvpair_name(pair);
@ -2759,10 +2758,6 @@ zfs_check_userprops(const char *fsname, nvlist_t *nvl)
nvpair_type(pair) != DATA_TYPE_STRING)
return (SET_ERROR(EINVAL));
if (error = zfs_secpolicy_write_perms(fsname,
ZFS_DELEG_PERM_USERPROP, CRED()))
return (error);
if (strlen(propname) >= ZAP_MAXNAMELEN)
return (SET_ERROR(ENAMETOOLONG));
@ -3429,12 +3424,11 @@ zfs_ioc_snapshot(const char *poolname, nvlist_t *innvl, nvlist_t *outnvl)
nvpair_t *pair;
(void) nvlist_lookup_nvlist(innvl, "props", &props);
if ((error = zfs_check_userprops(poolname, props)) != 0)
return (error);
if (!nvlist_empty(props) &&
zfs_earlier_version(poolname, SPA_VERSION_SNAP_PROPS))
return (SET_ERROR(ENOTSUP));
if ((error = zfs_check_userprops(props)) != 0)
return (error);
if (nvlist_lookup_nvlist(innvl, "snaps", &snaps) != 0)
return (SET_ERROR(EINVAL));
@ -3442,7 +3436,7 @@ zfs_ioc_snapshot(const char *poolname, nvlist_t *innvl, nvlist_t *outnvl)
for (pair = nvlist_next_nvpair(snaps, NULL); pair != NULL;
pair = nvlist_next_nvpair(snaps, pair)) {
const char *name = nvpair_name(pair);
const char *cp = strchr(name, '@');
char *cp = strchr(name, '@');
/*
* The snap name must contain an @, and the part after it must
@ -3459,6 +3453,18 @@ zfs_ioc_snapshot(const char *poolname, nvlist_t *innvl, nvlist_t *outnvl)
(name[poollen] != '/' && name[poollen] != '@'))
return (SET_ERROR(EXDEV));
/*
* Check for permission to set the properties on the fs.
*/
if (!nvlist_empty(props)) {
*cp = '\0';
error = zfs_secpolicy_write_perms(name,
ZFS_DELEG_PERM_USERPROP, CRED());
*cp = '@';
if (error != 0)
return (error);
}
/* This must be the only snap of this fs. */
for (nvpair_t *pair2 = nvlist_next_nvpair(snaps, pair);
pair2 != NULL; pair2 = nvlist_next_nvpair(snaps, pair2)) {