No thanks to 64-bit windows, with 64-bit pid_t, we have to avoid
constructs like 'int pid'. Our API in libvirt-qemu cannot be
changed without breaking ABI; but then again, libvirt-qemu can
only be used on systems that support UNIX sockets, which rules
out Windows (even if qemu could be compiled there) - so for all
points on the call chain that interact with this API decision,
we require a different variable name to make it clear that we
audited the use for safety.
Adding a syntax-check rule only solves half the battle; anywhere
that uses printf on a pid_t still needs to be converted, but that
will be a separate patch.
* cfg.mk (sc_correct_id_types): New syntax check.
* src/libvirt-qemu.c (virDomainQemuAttach): Document why we didn't
use pid_t for pid, and validate for overflow.
* include/libvirt/libvirt-qemu.h (virDomainQemuAttach): Tweak name
for syntax check.
* src/vmware/vmware_conf.c (vmwareExtractPid): Likewise.
* src/driver.h (virDrvDomainQemuAttach): Likewise.
* tools/virsh.c (cmdQemuAttach): Likewise.
* src/remote/qemu_protocol.x (qemu_domain_attach_args): Likewise.
* src/qemu_protocol-structs (qemu_domain_attach_args): Likewise.
* src/util/cgroup.c (virCgroupPidCode, virCgroupKillInternal):
Likewise.
* src/qemu/qemu_command.c(qemuParseProcFileStrings): Likewise.
(qemuParseCommandLinePid): Use pid_t for pid.
* daemon/libvirtd.c (daemonForkIntoBackground): Likewise.
* src/conf/domain_conf.h (_virDomainObj): Likewise.
* src/probes.d (rpc_socket_new): Likewise.
* src/qemu/qemu_command.h (qemuParseCommandLinePid): Likewise.
* src/qemu/qemu_driver.c (qemudGetProcessInfo, qemuDomainAttach):
Likewise.
* src/qemu/qemu_process.c (qemuProcessAttach): Likewise.
* src/qemu/qemu_process.h (qemuProcessAttach): Likewise.
* src/uml/uml_driver.c (umlGetProcessInfo): Likewise.
* src/util/virnetdev.h (virNetDevSetNamespace): Likewise.
* src/util/virnetdev.c (virNetDevSetNamespace): Likewise.
* tests/testutils.c (virtTestCaptureProgramOutput): Likewise.
* src/conf/storage_conf.h (_virStoragePerms): Use mode_t, uid_t,
and gid_t rather than int.
* src/security/security_dac.c (virSecurityDACSetOwnership): Likewise.
* src/conf/storage_conf.c (virStorageDefParsePerms): Avoid
compiler warning.
This eliminates the warning message reported in:
https://bugzilla.redhat.com/show_bug.cgi?id=624447
It was caused by a failure to open an image file that is not
accessible by root (the uid libvirtd is running as) because it's on a
root-squash NFS share, owned by a different user, with permissions of
660 (or maybe 600).
The solution is to use virFileOpenAs() rather than open(). The
codepath that generates the error is during qemuSetupDiskCGroup(), but
the actual open() is in a lower-level generic function called from
many places (virDomainDiskDefForeachPath), so some other pieces of the
code were touched just to add dummy (or possibly useful) uid and gid
arguments.
Eliminating this warning message has the nice side effect that the
requested operation may even succeed (which in this case isn't
necessary, but shouldn't hurt anything either).
When sVirt is integrated with the LXC driver, it will be neccessary
to invoke the security driver APIs using only a virDomainDefPtr
since the lxc_container.c code has no virDomainObjPtr available.
Aside from two functions which want obj->pid, every bit of the
security driver code only touches obj->def. So we don't need to
pass a virDomainObjPtr into the security drivers, a virDomainDefPtr
is sufficient. Two functions also gain a 'pid_t pid' argument.
* src/qemu/qemu_driver.c, src/qemu/qemu_hotplug.c,
src/qemu/qemu_migration.c, src/qemu/qemu_process.c,
src/security/security_apparmor.c,
src/security/security_dac.c,
src/security/security_driver.h,
src/security/security_manager.c,
src/security/security_manager.h,
src/security/security_nop.c,
src/security/security_selinux.c,
src/security/security_stack.c: Change all security APIs to use a
virDomainDefPtr instead of virDomainObjPtr
Network disks don't have paths to be resolved or files to be checked
for ownership. ee3efc41e6 checked this
for some image label functions, but was partially reverted in a
refactor. This finishes adding the check to each security driver's
set and restore label methods for images.
Signed-off-by: Josh Durgin <josh.durgin@dreamhost.com>
This patch fixes the regression with using named pipes for qemu serial
devices noted in:
https://bugzilla.redhat.com/show_bug.cgi?id=740478
The problem was that, while new code in libvirt looks for a single
bidirectional fifo of the name given in the config, then relabels that
and continues without looking for / relabelling the two unidirectional
fifos named ${name}.in and ${name}.out, qemu looks in the opposite
order. So if the user had naively created all three fifos, libvirt
would relabel the bidirectional fifo to allow qemu access, but qemu
would attempt to use the two unidirectional fifos and fail (because it
didn't have proper permissions/rights).
This patch changes the order that libvirt looks for the fifos to match
what qemu does - first it looks for the dual fifos, then it looks for
the single bidirectional fifo. If it finds the dual unidirectional
fifos first, it labels/chowns them and ignores any possible
bidirectional fifo.
(Note commit d37c6a3a (which first appeared in libvirt-0.9.2) added
the code that checked for a bidirectional fifo. Prior to that commit,
bidirectional fifos for serial devices didn't work because libvirt
always required the ${name}.(in|out) fifos to exist, and qemu would
always prefer those.
The virSecurityManagerSetProcessFDLabel method was introduced
after a mis-understanding from a conversation about SELinux
socket labelling. The virSecurityManagerSetSocketLabel method
should have been used for all such scenarios.
* src/security/security_apparmor.c, src/security/security_apparmor.c,
src/security/security_driver.h, src/security/security_manager.c,
src/security/security_manager.h, src/security/security_selinux.c,
src/security/security_stack.c: Remove SetProcessFDLabel driver
This API labels all sockets created until ClearSocketLabel is called in
a way that a vm can access them (i.e., they are labeled with svirt_t
based label in SELinux).
The APIs are designed to label a socket in a way that the libvirt daemon
itself is able to access it (i.e., in SELinux the label is virtd_t based
as opposed to svirt_* we use for labeling resources that need to be
accessed by a vm). The new name reflects this.
Add a new security driver method for labelling an FD with
the process label, rather than the image label
* src/libvirt_private.syms, src/security/security_apparmor.c,
src/security/security_dac.c, src/security/security_driver.h,
src/security/security_manager.c, src/security/security_manager.h,
src/security/security_selinux.c, src/security/security_stack.c:
Add virSecurityManagerSetProcessFDLabel & impl
The virSecurityManagerSetFDLabel method is used to label
file descriptors associated with disk images. There will
shortly be a need to label other file descriptors in a
different way. So the current name is ambiguous. Rename
the method to virSecurityManagerSetImageFDLabel to clarify
its purpose
* src/libvirt_private.syms,
src/qemu/qemu_migration.c, src/qemu/qemu_process.c,
src/security/security_apparmor.c, src/security/security_dac.c,
src/security/security_driver.h, src/security/security_manager.c,
src/security/security_manager.h, src/security/security_selinux.c,
src/security/security_stack.c: s/FDLabel/ImageFDLabel/
This fixes:
https://bugzilla.redhat.com/show_bug.cgi?id=702044https://bugzilla.redhat.com/show_bug.cgi?id=709454
Both of these complain of a failure to use an image file that resides
on a read-only NFS volume. The function in the DAC security driver
that chowns image files to the qemu user:group before using them
already has special cases to ignore failure of chown on read-only file
systems, and in a few other cases, but it hadn't been checking for
EINVAL, which is what is returned if the qemu user doesn't even exist
on the NFS server.
Since the explanation of EINVAL in the chown man page almost exactly
matches the log message already present for the case of EOPNOTSUPP,
I've just added EINVAL to that same conditional.
When setting up a FIFO for QEMU, it allows either a pair
of fifos used unidirectionally, or a single fifo used
bidirectionally. Look for the bidirectional fifo first
when labelling since that is more useful
* src/security/security_dac.c,
src/security/security_selinux.c: Fix fifo handling
On cygwin:
CC libvirt_driver_security_la-security_dac.lo
security/security_dac.c: In function 'virSecurityDACSetProcessLabel':
security/security_dac.c:618: warning: format '%d' expects type 'int', but argument 7 has type 'uid_t' [-Wformat]
We've done this before (see src/util/util.c).
* src/security/security_dac.c (virSecurityDACSetProcessLabel): On
cygwin, uid_t is a 32-bit long.
virSecurityDAC{Set,Restore}ChardevCallback expect virSecurityManagerPtr,
but are passed virDomainObjPtr instead. This makes
virSecurityDACSetChardevLabel set a wrong uid/gid on chardevs. This
patch fixes this behaviour.
Signed-off-by: Soren Hansen <soren@linux2go.dk>
Done mechanically with:
$ git grep -l '\bDEBUG0\? *(' | xargs -L1 sed -i 's/\bDEBUG0\? *(/VIR_&/'
followed by manual deletion of qemudDebug in daemon/libvirtd.c, along
with a single 'make syntax-check' fallout in the same file, and the
actual deletion in src/util/logging.h.
* src/util/logging.h (DEBUG, DEBUG0): Delete.
* daemon/libvirtd.h (qemudDebug): Likewise.
* global: Change remaining clients over to VIR_DEBUG counterpart.
A need was found to set the SELinux context label on an open fd (a
pipe, as a matter of fact). This patch adds a function to the security
driver API that will set the label on an open fd to secdef.label. For
all drivers other than the SELinux driver, it's a NOP. For the SElinux
driver, it calls fsetfilecon().
If the return is a failure, it only returns error up to the caller if
1) the desired label is different from the existing label, 2) the
destination fd is of a type that supports setting the selinux context,
and 3) selinux is in enforcing mode. Otherwise it will return
success. This follows the pattern of the existing function
SELinuxSetFilecon().
The current security driver usage requires horrible code like
if (driver->securityDriver &&
driver->securityDriver->domainSetSecurityHostdevLabel &&
driver->securityDriver->domainSetSecurityHostdevLabel(driver->securityDriver,
vm, hostdev) < 0)
This pair of checks for NULL clutters up the code, making the driver
calls 2 lines longer than they really need to be. The goal of the
patchset is to change the calling convention to simply
if (virSecurityManagerSetHostdevLabel(driver->securityDriver,
vm, hostdev) < 0)
The first check for 'driver->securityDriver' being NULL is removed
by introducing a 'no op' security driver that will always be present
if no real driver is enabled. This guarentees driver->securityDriver
!= NULL.
The second check for 'driver->securityDriver->domainSetSecurityHostdevLabel'
being non-NULL is hidden in a new abstraction called virSecurityManager.
This separates the driver callbacks, from main internal API. The addition
of a virSecurityManager object, that is separate from the virSecurityDriver
struct also allows for security drivers to carry state / configuration
information directly. Thus the DAC/Stack drivers from src/qemu which
used to pull config from 'struct qemud_driver' can now be moved into
the 'src/security' directory and store their config directly.
* src/qemu/qemu_conf.h, src/qemu/qemu_driver.c: Update to
use new virSecurityManager APIs
* src/qemu/qemu_security_dac.c, src/qemu/qemu_security_dac.h
src/qemu/qemu_security_stacked.c, src/qemu/qemu_security_stacked.h:
Move into src/security directory
* src/security/security_stack.c, src/security/security_stack.h,
src/security/security_dac.c, src/security/security_dac.h: Generic
versions of previous QEMU specific drivers
* src/security/security_apparmor.c, src/security/security_apparmor.h,
src/security/security_driver.c, src/security/security_driver.h,
src/security/security_selinux.c, src/security/security_selinux.h:
Update to take virSecurityManagerPtr object as the first param
in all callbacks
* src/security/security_nop.c, src/security/security_nop.h: Stub
implementation of all security driver APIs.
* src/security/security_manager.h, src/security/security_manager.c:
New internal API for invoking security drivers
* src/libvirt.c: Add missing debug for security APIs
