Fix LVM2 volume names containing hyphens (#245)

(DIS-1982)
fox-it · May 2, 2023 · 6e02f7a · 6e02f7a
1 parent e3a68de
commit 6e02f7a
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Showing 3 changed files with 16 additions and 6 deletions.
diff --git a/dissect/target/plugins/os/unix/_os.py b/dissect/target/plugins/os/unix/_os.py
@@ -4,7 +4,7 @@
 import re
 import uuid
 from struct import unpack
-from typing import Iterator, Optional, Tuple, Union
+from typing import Iterator, Optional, Union
 
 from dissect.target.filesystem import Filesystem
 from dissect.target.helpers.fsutil import TargetPath
@@ -277,7 +277,7 @@ def _get_architecture(self, os: str = "unix") -> Optional[str]:
 def parse_fstab(
     fstab: TargetPath,
     log: logging.Logger = log,
-) -> Iterator[Tuple[Union[uuid.UUID, str], str, str, str]]:
+) -> Iterator[tuple[Union[uuid.UUID, str], str, str, str]]:
     """Parse fstab file and return a generator that streams the details of entries,
     with unsupported FS types and block devices filtered away.
     """
@@ -315,7 +315,9 @@ def parse_fstab(
         if dev.startswith(("/dev/mapper", "/dev/gpt")):
             volume_name = dev.rsplit("/")[-1]
         elif dev.startswith("/dev/") and dev.count("/") == 3:
-            volume_name = "-".join(dev.rsplit("/")[-2:])
+            # When composing a vg-lv name, LVM2 replaces hyphens with double hyphens in the vg and lv names
+            # Emulate that here when combining the vg and lv names
+            volume_name = "-".join(part.replace("-", "--") for part in dev.rsplit("/")[-2:])
         elif dev.startswith("UUID="):
             dev_id = dev.split("=")[1]
             try:

diff --git a/dissect/target/volumes/lvm.py b/dissect/target/volumes/lvm.py
@@ -48,5 +48,7 @@ def _detect_volume(fh: BinaryIO) -> bool:
 
     def _volumes(self) -> Iterator[Volume]:
         for num, lv in enumerate(self.lvm.volume_group.logical_volumes):
-            name = f"{lv.vg.name}-{lv.metadata.name}"
+            # When composing a vg-lv name, LVM2 replaces hyphens with double hyphens in the vg and lv names
+            # Emulate that here for the volume name
+            name = f"{lv.vg.name.replace('-', '--')}-{lv.metadata.name.replace('-', '--')}"
             yield Volume(lv, num, None, lv.size, None, name, raw=lv, vs=self)
diff --git a/tests/test_plugins_os_unix.py b/tests/test_plugins_os_unix.py
@@ -28,6 +28,10 @@
 UUID=F631-BECA                            /boot/efi    vfat    defaults,discard,umask=0077   0    0
 
 /dev/disk/cloud/azure_resource-part1      /mnt         auto    defaults,nofail,x-systemd.requires=cloud-init.service,comment=cloudconfig   0   2
+
+/dev/mapper/vg--main-lv--var              /var         auto    default             0    2
+
+/dev/vg-main/lv-data                      /data        auto    default             0    2
 """  # noqa
 
 
@@ -41,14 +45,16 @@ def test_parse_fstab():
 
         records = list(parse_fstab(fs.path("/etc/fstab")))
 
-    # 8 input records minus
+    # 10 input records minus
     #   2 unsupported mount devices (proc, /dev/disk/cloud/azure_resource-part1)
     #   2 swap partitions
     #   1 root partition
-    # = 3 expected results
+    # = 5 expected results
 
     assert set(records) == {
         (UUID("5d1f1508-069b-4274-9bfa-ae2bf7ffb5e0"), None, "ext4", "/home"),
         (UUID("28a25297-9825-4f87-ac41-f9c20cd5db4f"), None, "ext4", "/boot"),
         ("F631-BECA", None, "vfat", "/boot/efi"),
+        (None, "vg--main-lv--var", "auto", "/var"),
+        (None, "vg--main-lv--data", "auto", "/data"),
     }