qemu-ns: Detect /dev/* mount point duplicates better

https://bugzilla.redhat.com/show_bug.cgi?id=1495511

When creating new /dev for domain ran in namespace we try to
preserve all sub-mounts of /dev. Well, not quite all. For
instance if /dev/foo/bar and /dev/foo are both mount points, only
/dev/foo needs preserving. /dev/foo/bar is preserved with it too.
Now, to identify such cases like this one STRPREFIX() is used.
That is not good enough. While it works for [/dev/foo/bar;
/dev/foo] case, it fails for [/dev/prefix; /dev/prefix2] where
the strings share the same prefix but are in fact two different
paths. The solution is to use STRSKIP().

Signed-off-by: Michal Privoznik <mprivozn@redhat.com>
Reviewed-by: Erik Skultety <eskultet@redhat.com>
This commit is contained in:
Michal Privoznik 2017-10-19 15:23:15 +02:00
parent eebfdcb41e
commit 4f15707202

View File

@ -8222,7 +8222,9 @@ qemuDomainGetPreservedMounts(virQEMUDriverConfigPtr cfg,
for (i = 1; i < nmounts; i++) { for (i = 1; i < nmounts; i++) {
j = i + 1; j = i + 1;
while (j < nmounts) { while (j < nmounts) {
if (STRPREFIX(mounts[j], mounts[i])) { char *c = STRSKIP(mounts[j], mounts[i]);
if (c && *c == '/') {
VIR_DEBUG("Dropping path %s because of %s", mounts[j], mounts[i]); VIR_DEBUG("Dropping path %s because of %s", mounts[j], mounts[i]);
VIR_DELETE_ELEMENT(mounts, j, nmounts); VIR_DELETE_ELEMENT(mounts, j, nmounts);
} else { } else {