From c799ba9ab61762c882c888393224f770ca51887c Mon Sep 17 00:00:00 2001
From: Giuseppe Scrivano <gscrivan@redhat.com>
Date: Mon, 11 Mar 2024 13:55:02 +0100
Subject: [PATCH] [release-1.45] overlay: create the merged path only if it
 does not exist

follow-up for ccb70a79a69a1a5137ff24720520534bfbcc2316

more information here: https://github.com/containers/storage/issues/1827#issuecomment-1988332922

Addresses: https://issues.redhat.com/browse/ACCELFIX-244

Signed-off-by: Giuseppe Scrivano <gscrivan@redhat.com>
Signed-off-by: tomsweeneyredhat <tsweeney@redhat.com>
---
 drivers/overlay/overlay.go  | 10 ++++++----
 tests/overlay-recreate.bats |  5 ++++-
 2 files changed, 10 insertions(+), 5 deletions(-)

diff --git a/drivers/overlay/overlay.go b/drivers/overlay/overlay.go
index d6abb7628c..15b343d156 100644
--- a/drivers/overlay/overlay.go
+++ b/drivers/overlay/overlay.go
@@ -1479,9 +1479,11 @@ func (d *Driver) get(id string, disableShifting bool, options graphdriver.MountO
 	}
 
 	mergedDir := path.Join(dir, "merged")
-	// Create the driver merged dir
-	if err := idtools.MkdirAs(mergedDir, 0700, rootUID, rootGID); err != nil && !os.IsExist(err) {
-		return "", err
+	// Attempt to create the merged dir only if it doesn't exist.
+	if _, err := os.Stat(mergedDir); err != nil && os.IsNotExist(err) {
+		if err := idtools.MkdirAs(mergedDir, 0o700, rootUID, rootGID); err != nil && !os.IsExist(err) {
+			return "", err
+		}
 	}
 	if count := d.ctr.Increment(mergedDir); count > 1 {
 		return mergedDir, nil
@@ -1639,7 +1641,7 @@ func (d *Driver) get(id string, disableShifting bool, options graphdriver.MountO
 
 // Put unmounts the mount path created for the give id.
 func (d *Driver) Put(id string) error {
-	dir, _, inAdditionalStore := d.dir2(id)
+	dir, inAdditionalStore := d.dir2(id)
 	if _, err := os.Stat(dir); err != nil {
 		return err
 	}
diff --git a/tests/overlay-recreate.bats b/tests/overlay-recreate.bats
index 038a48810a..c3ebbb3297 100644
--- a/tests/overlay-recreate.bats
+++ b/tests/overlay-recreate.bats
@@ -18,7 +18,8 @@ load helpers
 	storage unmount "$lowerlayer"
 	storage mount "$midlayer"
 	storage unmount "$midlayer"
-	storage mount "$upperlayer"
+	run storage --debug=false mount "$upperlayer"
+	merged_dir="$output"
 	storage unmount "$upperlayer"
 	# okay, but how about this?
 	rm -v ${TESTDIR}/root/overlay/*/link
@@ -27,6 +28,8 @@ load helpers
 	storage unmount "$lowerlayer"
 	storage mount "$midlayer"
 	storage unmount "$midlayer"
+	# check it works if we delete the merged directory.
+	rmdir "$merged_dir"
 	storage mount "$upperlayer"
 	storage unmount "$upperlayer"
 	# okay, not bad, kid.