[libvirt] [PATCH RFC] qemu: caps: Don't try to ask for CAP_DAC_OVERRIDE if non-root
It will not work. This breaks qemu capabilities probing as a user. --- src/qemu/qemu_capabilities.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) diff --git a/src/qemu/qemu_capabilities.c b/src/qemu/qemu_capabilities.c index 7ed5f94803..81ef0357e7 100644 --- a/src/qemu/qemu_capabilities.c +++ b/src/qemu/qemu_capabilities.c @@ -4524,7 +4524,8 @@ virQEMUCapsInitQMPCommandRun(virQEMUCapsInitQMPCommandPtr cmd, #if WITH_CAPNG /* QEMU might run into permission issues, e.g. /dev/sev (0600), override * them just for the purpose of probing */ - virCommandAllowCap(cmd->cmd, CAP_DAC_OVERRIDE); + if (geteuid() == 0) + virCommandAllowCap(cmd->cmd, CAP_DAC_OVERRIDE); #endif virCommandSetGID(cmd->cmd, cmd->runGid); -- 2.20.1
On Mon, Feb 04, 2019 at 16:26:02 +0100, Peter Krempa wrote:
It will not work. This breaks qemu capabilities probing as a user. --- src/qemu/qemu_capabilities.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-)
diff --git a/src/qemu/qemu_capabilities.c b/src/qemu/qemu_capabilities.c index 7ed5f94803..81ef0357e7 100644 --- a/src/qemu/qemu_capabilities.c +++ b/src/qemu/qemu_capabilities.c @@ -4524,7 +4524,8 @@ virQEMUCapsInitQMPCommandRun(virQEMUCapsInitQMPCommandPtr cmd, #if WITH_CAPNG /* QEMU might run into permission issues, e.g. /dev/sev (0600), override * them just for the purpose of probing */ - virCommandAllowCap(cmd->cmd, CAP_DAC_OVERRIDE); + if (geteuid() == 0)
Possibly replacing this with driver->privileged for the qemu driver but that is not easily accessible.
+ virCommandAllowCap(cmd->cmd, CAP_DAC_OVERRIDE); #endif
virCommandSetGID(cmd->cmd, cmd->runGid); -- 2.20.1
-- libvir-list mailing list libvir-list@redhat.com https://www.redhat.com/mailman/listinfo/libvir-list
On Mon, Feb 04, 2019 at 04:32:52PM +0100, Peter Krempa wrote:
On Mon, Feb 04, 2019 at 16:26:02 +0100, Peter Krempa wrote:
It will not work. This breaks qemu capabilities probing as a user. --- src/qemu/qemu_capabilities.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-)
diff --git a/src/qemu/qemu_capabilities.c b/src/qemu/qemu_capabilities.c index 7ed5f94803..81ef0357e7 100644 --- a/src/qemu/qemu_capabilities.c +++ b/src/qemu/qemu_capabilities.c @@ -4524,7 +4524,8 @@ virQEMUCapsInitQMPCommandRun(virQEMUCapsInitQMPCommandPtr cmd, #if WITH_CAPNG /* QEMU might run into permission issues, e.g. /dev/sev (0600), override * them just for the purpose of probing */ - virCommandAllowCap(cmd->cmd, CAP_DAC_OVERRIDE); + if (geteuid() == 0)
Possibly replacing this with driver->privileged for the qemu driver but that is not easily accessible.
It doesn't really matter as privileged == (geteuid() == 0) since we purged the hack for Solaris that tried to run privileged libvirtd as non-root for Xen. We've got many other cases using geteuid() == 0 where they cannot access the 'privileged' flag alrady. Regards, Daniel -- |: https://berrange.com -o- https://www.flickr.com/photos/dberrange :| |: https://libvirt.org -o- https://fstop138.berrange.com :| |: https://entangle-photo.org -o- https://www.instagram.com/dberrange :|
On Mon, Feb 04, 2019 at 04:26:02PM +0100, Peter Krempa wrote:
It will not work. This breaks qemu capabilities probing as a user. --- src/qemu/qemu_capabilities.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-)
diff --git a/src/qemu/qemu_capabilities.c b/src/qemu/qemu_capabilities.c index 7ed5f94803..81ef0357e7 100644 --- a/src/qemu/qemu_capabilities.c +++ b/src/qemu/qemu_capabilities.c @@ -4524,7 +4524,8 @@ virQEMUCapsInitQMPCommandRun(virQEMUCapsInitQMPCommandPtr cmd, #if WITH_CAPNG /* QEMU might run into permission issues, e.g. /dev/sev (0600), override * them just for the purpose of probing */ - virCommandAllowCap(cmd->cmd, CAP_DAC_OVERRIDE); + if (geteuid() == 0) + virCommandAllowCap(cmd->cmd, CAP_DAC_OVERRIDE);
This should be enough of a fix with the current code base as it won't clash with the other two CAP_SYS_RAWIO and CAP_NET_ADMIN which should still fail when used with the session daemon as expected. Reviewed-by: Erik Skultety <eskultet@redhat.com>
participants (3)
-
Daniel P. Berrangé -
Erik Skultety -
Peter Krempa