it is strange from what I test, it seems o+x is not necessary but sufficient.Sorry this took me a while to get back to you. Answers below. Do you want to pick this back up in the overall kimchi thread? On Thu, 2014-03-06 at 13:29 +0800, Sheldon wrote:On 03/04/2014 06:38 AM, Christy Perez wrote:On Wed, 2014-02-26 at 20:26 +0800, Sheldon wrote:On 02/25/2014 08:23 AM, Christy Perez wrote:qemu can't use an ISO if 'other' can't execute all the directories containing the file. Return an error explaning this, and suggest the way to fix it. Signed-off-by: Christy Perez <christy@linux.vnet.ibm.com> --- po/en_US.po | 6 ++++++ src/kimchi/exception.py | 4 ++++ src/kimchi/i18n.py | 2 ++ src/kimchi/utils.py | 9 +++++++++ src/kimchi/vmtemplate.py | 7 +++++-- 5 files changed, 26 insertions(+), 2 deletions(-) diff --git a/po/en_US.po b/po/en_US.po index ca1fe86..38af64c 100644 --- a/po/en_US.po +++ b/po/en_US.po @@ -674,6 +674,12 @@ msgid "Bad format while reading volume descriptor in ISO %(filename)s" msgstr "" #, python-format +msgid "The hypervisor doesn't have permission to use this ISO %(filename)s. \ + Consider moving it under /var/lib/libvirt, or \ + (not recommended) 'chmod -R o+x 'path_to_iso'." +msgstr "" + +#, python-format msgid "Virtual machine %(name)s already exists" msgstr "" diff --git a/src/kimchi/exception.py b/src/kimchi/exception.py index 2d974a8..263bd0c 100644 --- a/src/kimchi/exception.py +++ b/src/kimchi/exception.py @@ -75,6 +75,10 @@ class InvalidParameter(KimchiException): pass +class InvalidPermission(KimchiException): + pass + + class InvalidOperation(KimchiException): pass diff --git a/src/kimchi/i18n.py b/src/kimchi/i18n.py index fea0184..05b347c 100644 --- a/src/kimchi/i18n.py +++ b/src/kimchi/i18n.py @@ -57,6 +57,8 @@ messages = { "KCHISO0005E": _("Invalid El Torito boot indicator in ISO %(filename)s"), "KCHISO0006E": _("Unexpected volume type for primary volume in ISO %(filename)s"), "KCHISO0007E": _("Bad format while reading volume descriptor in ISO %(filename)s"), + "KCHISO0008E": _("The hypervisor doesn't have permission to use this ISO %(filename)s. \ + Consider moving it under /var/lib/libvirt, or (not recommended) 'chmod -R o+x 'path_to_iso'." ), "KCHVM0001E": _("Virtual machine %(name)s already exists"), "KCHVM0002E": _("Virtual machine %(name)s does not exist"), diff --git a/src/kimchi/utils.py b/src/kimchi/utils.py index 6be1c04..c325be3 100644 --- a/src/kimchi/utils.py +++ b/src/kimchi/utils.py @@ -27,6 +27,7 @@ import psutil import re import subprocess import urllib2 +import stat from threading import Timer from cherrypy.lib.reprconf import Parser @@ -234,3 +235,11 @@ def run_setfacl_set_attr(path, attr="r", user=""): set_user = ["setfacl", "--modify", "user:%s:%s" % (user, attr), path] out, error, ret = run_command(set_user) return ret == 0 + +def check_iso_path_perm(path): + """ + libvirt requires that all parent dirs have o+x + """ + if path == '/': return True + return os.stat(path).st_mode & stat.S_IXOTH and \ + check_iso_path_perm(os.path.dirname(path))just test other's permission is not enough. 1. when the path user is qemu. why we need S_IXOTH?That's what the libvirt doc says, and what I've found is needed: " The directories containing disk images must either have their ownership set to match the user/group configured for QEMU, or their UNIX file permissions must have the 'execute/search' bit enabled for 'others'. " Source: http://libvirt.org/drvqemu.htmlso that's means the disk images without S_IXOTH, qemu still can have search permissions right?Yep. The images themselves won't have S_IXOTH. qemu will own them, though: [root@kop4 kimchi-ginger-pkvm]# ls -lah /var/lib | grep libvirt drwxr-xr-x. 9 root root 4.0K Feb 19 11:16 libvirt [root@kop4 kimchi-ginger-pkvm]# ls -lah /var/lib/libvirt | grep images drwx--x--x. 2 root root 4.0K Mar 7 06:22 images [root@kop4 kimchi-ginger-pkvm]# ls -lah /var/lib/libvirt/images/ total 2.9G drwx--x--x. 2 root root 4.0K Mar 7 06:22 . drwxr-xr-x. 9 root root 4.0K Feb 19 11:16 .. -rw-------. 1 qemu qemu 193K Mar 7 06:22 2f7130eb-539c-4401-82eb-cccd18708f56-0.img -r--r--r--. 1 qemu qemu 2.9G Mar 7 06:20 RHEL-7.0-20140226.0-Server-ppc64-dvd1.isoo+x is sufficient but not necessary condition?o+x is necessary.2. as you said "libvirt requires that all parent dirs have o+x" you has adding 'X' to the ACL for each directory to try it. I wander have check your ACL enable?I don't think the ACL will be enough. It looks like it has to have o+x for all parent paths. And yes, my ACLs were enabled on my filesystem.That's strangely. but the docs http://libvirt.org/drvqemu.html says: it simple to set o+x, means this is the only way.Yes, I think so.
""" The simplest option is the latter one, of just enabling the 'execute/search' bit. For any directory to be used for storing disk images, this can be achieved by running the following command on the directory itself, and any parent directories chmod o+x /path/to/directory In particular note that if using the "system" instance and attempting to store disk images in a user home directory, the default permissions on $HOME are typically too restrictive to allow access. """3. have you check add qemu in all the paths group? and open set g+x? can you try my patch, seen it can works? add a method to probe the permission as qemu userI don't see how the patch listed there will apply. Maybe github reformats it strangely when you paste it in? Even so, as I pasted from the libvirt doc, I don't think that will be enough to make libvirt happy.save as, and git apply. but I think it will not successfully, for the upstream changes so quickly. Yes, we should make libvirt and kimchi user happy?I think it's a security leak to allow someone to put a file in one directory, and then we give o+x to every parent of it. If I put an ISO at /home/christy/example.iso and kimchi changed recursively all parents to o+x, it would give all users the ability to see what's in /home/.diff --git a/src/kimchi/vmtemplate.py b/src/kimchi/vmtemplate.py index af07ee3..76ac772 100644 --- a/src/kimchi/vmtemplate.py +++ b/src/kimchi/vmtemplate.py @@ -29,9 +29,9 @@ import urlparse from kimchi import isoinfo from kimchi import osinfo -from kimchi.exception import InvalidParameter, IsoFormatError +from kimchi.exception import InvalidParameter, IsoFormatError, InvalidPermission from kimchi.isoinfo import IsoImage - +from kimchi.utils import check_iso_path_perm QEMU_NAMESPACE = "xmlns:qemu='http://libvirt.org/schemas/domain/qemu/1.0'" @@ -55,6 +55,9 @@ class VMTemplate(object): iso_distro = iso_version = 'unknown' iso = args.get('cdrom', '') + if iso.startswith('/') and \ + not check_iso_path_perm(os.path.dirname(iso)): + raise InvalidPermission("KCHISO0008E", {'filename': iso}) if scan and len(iso) > 0: iso_distro, iso_version = self.get_iso_info(iso) if not iso.startswith('/'):Regards, - ChristyRegards, - Christy
-- Thanks and best regards! Sheldon Feng(冯少合)<shaohef@linux.vnet.ibm.com> IBM Linux Technology Center