[libvirt] [PATCH] qemu: Label uniqDir when probing capabilities

This does not cause a problem in usual scenarios thanks to us allowing CAP_DAC_OVERRIDE for the qemu process, however in some scenarios this might be an issue because the directory is created with mkdtemp(3) which explicitly creates that with 0700 permissions and qemu running as non-root cannot access that. The scenarios include: - Builds without CAPNG - Running libvirtd in a container [1] - and possibly others. [1] https://github.com/kubevirt/kubevirt/pull/2181#issuecomment-481840304 Signed-off-by: Martin Kletzander <mkletzan(a)redhat.com&gt; --- src/qemu/qemu_process.c | 16 ++++++++++++++++ 1 file changed, 16 insertions(+) diff --git a/src/qemu/qemu_process.c b/src/qemu/qemu_process.c index 47d8ca2ff163..2e2c4812fef7 100644 --- a/src/qemu/qemu_process.c +++ b/src/qemu/qemu_process.c @@ -8447,6 +8447,19 @@ qemuProcessQMPNew(const char *binary, } +static int +qemuProcessQEMULabelUniqPath(qemuProcessQMPPtr proc) { + /* We cannot use the security driver here, but we should not need to. */ + if (chown(proc->uniqDir, proc->runUid, -1) < 0) { + virReportSystemError(errno, + "Cannot chown uniq path: %s", proc->uniqDir); + return -1; + } + + return 0; +} + + static int qemuProcessQMPInit(qemuProcessQMPPtr proc) { @@ -8466,6 +8479,9 @@ qemuProcessQMPInit(qemuProcessQMPPtr proc) goto cleanup; } + if (qemuProcessQEMULabelUniqPath(proc) < 0) + goto cleanup; + if (virAsprintf(&proc->monpath, "%s/%s", proc->uniqDir, "qmp.monitor") < 0) goto cleanup; -- 2.21.0