On 2/6/23 19:08, Jim Fehlig wrote:

Similar to other error paths in qemuDomainUnshareNamespace(), jump to the cleanup label on umount error instead of directly returning -1.

Signed-off-by: Jim Fehlig <jfehlig@suse.com> ---

I noticed this while looking at a bug report containing the error. ATM I'm not sure why the umount failed, but have asked for more info in the bug

https://bugzilla.opensuse.org/show_bug.cgi?id=1207889

src/qemu/qemu_namespace.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/src/qemu/qemu_namespace.c b/src/qemu/qemu_namespace.c index 5769a4dfe0..833313d5a6 100644 --- a/src/qemu/qemu_namespace.c +++ b/src/qemu/qemu_namespace.c @@ -779,7 +779,7 @@ qemuDomainUnshareNamespace(virQEMUDriverConfig *cfg, #if defined(__linux__) if (umount("/dev") < 0) { virReportSystemError(errno, "%s", _("failed to umount devfs on /dev")); - return -1; + goto cleanup; } #endif /* !defined(__linux__) */

Reviewed-by: Michal Privoznik <mprivozn@redhat.com> And huge thanks to Martin Kletzander who actually came up with the root cause for this problem. My code does not handle multiple mounts on the same target. For instance: # mount | grep /dev udev on /dev type devtmpfs (rw,nosuid,noexec,relatime,size=10240k,nr_inodes=4061238,mode=755) devpts on /dev/pts type devpts (rw,relatime,gid=5,mode=620,ptmxmode=000) tmpfs on /dev/shm type tmpfs (rw,nosuid,nodev) mqueue on /dev/mqueue type mqueue (rw,nosuid,nodev,noexec,relatime) tmpfs2 on /dev/shm type tmpfs (rw,relatime) I've mounted /dev/shm for the second time as: # mount -t tmpfs tmpfs2 /dev/shm/ The problem is that qemuDomainGetPreservedMounts() drops the one of the /dev/shm entries, therefore, only one instance is moved to /var/run/libvirt/... leaving the other behind. Hence, failing umount(). I'll try to come up with a fix, unless somebody else beats me to it. Michal