Re: [libvirt] [PATCH 3/3] storage: Fix checking whether source filesystem is mounted

Right now, we use simple string comparison both on the source paths (mount's output vs pool's source) and the target (mount's mnt_dir vs pool's target). The problem are symlinks and mount indeed returns symlinks in its output, e.g. /dev/mappper/lvm_symlink. The same goes for the pool's source/target, so in order to successfully compare these two replace plain string comparison with virFileComparePaths which will resolve all symlinks and canonicalize the paths prior to comparison. Resolves: https://bugzilla.redhat.com/show_bug.cgi?id=1417203 Signed-off-by: Erik Skultety <eskultet(a)redhat.com&gt; --- src/storage/storage_backend_fs.c | 12 ++++++++++-- 1 file changed, 10 insertions(+), 2 deletions(-) diff --git a/src/storage/storage_backend_fs.c b/src/storage/storage_backend_fs.c index fe4705b..fae1c03 100644 --- a/src/storage/storage_backend_fs.c +++ b/src/storage/storage_backend_fs.c @@ -301,6 +301,7 @@ virStorageBackendFileSystemIsMounted(virStoragePoolObjPtr pool) FILE *mtab; struct mntent ent; char buf[1024]; + int rc1, rc2; if ((mtab = fopen(_PATH_MOUNTED, "r")) == NULL) { virReportSystemError(errno, @@ -313,8 +314,15 @@ virStorageBackendFileSystemIsMounted(virStoragePoolObjPtr pool) if (!(src = virStorageBackendFileSystemGetPoolSource(pool))) goto cleanup; - if (STREQ(ent.mnt_dir, pool->def->target.path) && - STREQ(ent.mnt_fsname, src)) { + /* compare both mount destinations and sources to be sure the mounted + * FS pool is really the one we're looking for + */ + if ((rc1 = virFileComparePaths(ent.mnt_dir, + pool->def->target.path)) < 0 || + (rc2 = virFileComparePaths(ent.mnt_fsname, src)) < 0) + goto cleanup; + + if (rc1 == 0 && rc2 == 0) {

ret = 1; goto cleanup; }