dissect-image: Explicitly remove partitions when done with image

When closing a loop device, the kernel will asynchronously remove
the probed partitions. This can lead to race conditions where we
try to reuse a partition device that still needs to be removed by
the kernel. To avoid such issues, let's explicitly try to remove
any partitions using BLKPG_DEL_PARTITION when we're done with an
image.

To make sure we don't try to remove partitions when we want them
to remain (e.g. systemd-dissect --mount), we add
dissected_image_relinquish() in a similar vein to loop_device_relinquish()
and decrypted_image_relinquish().

1 files changed, 2 insertions, 0 deletions

diff --git a/src/dissect/dissect.c b/src/dissect/dissect.c
index bd94a755db..0239d9b394 100644
--- a/src/dissect/dissect.c
+++ b/src/dissect/dissect.c
@@ -648,6 +648,7 @@ static int action_mount(DissectedImage *m, LoopDevice *d) {
                         return log_error_errno(r, "Failed to relinquish DM devices: %m");
         }
 
+        dissected_image_relinquish(m);
         loop_device_relinquish(d);
         return 0;
 }
@@ -700,6 +701,7 @@ static int action_copy(DissectedImage *m, LoopDevice *d) {
                         return log_error_errno(r, "Failed to relinquish DM devices: %m");
         }
 
+        dissected_image_relinquish(m);
         loop_device_relinquish(d);
 
         if (arg_action == ACTION_COPY_FROM) {