From ea556ef1d9e26802842577597e3736528f54ee0f Mon Sep 17 00:00:00 2001

From: Jan Kara <jack@suse.cz>

Date: Thu, 20 Jan 2022 13:16:39 +0100

Subject: loopdev: Do not treat errors when detecting overlap as fatal

When looking for overlapping loop device we can fail getting some loop

device properties when we race with device autoclear. Just squelsh these

errors and try next loop device.

Addresses: https://bugzilla.redhat.com/bugzilla/show_bug.cgi?id=2117203

Signed-off-by: Jan Kara <jack@suse.cz>

---

 lib/loopdev.c | 15 +++++++++------

 1 file changed, 9 insertions(+), 6 deletions(-)

diff --git a/lib/loopdev.c b/lib/loopdev.c

index db3aab29f..511f8a0d6 100644

--- a/lib/loopdev.c

+++ b/lib/loopdev.c

@@ -1773,10 +1773,13 @@ int loopcxt_find_overlap(struct loopdev_cxt *lc, const char *filename,

 		rc = loopcxt_is_used(lc, hasst ? &st : NULL,

 				     filename, offset, sizelimit, 0);

-		if (!rc)

-			continue;	/* unused */

-		if (rc < 0)

-			break;		/* error */

+		/*

+		 * Either the loopdev is unused or we've got an error which can

+		 * happen when we are racing with device autoclear. Just ignore

+		 * this loopdev...

+		 */

+		if (rc <= 0)

+			continue;

 		DBG(CXT, ul_debugobj(lc, "found %s backed by %s",

 			loopcxt_get_device(lc), filename));

@@ -1785,13 +1788,13 @@ int loopcxt_find_overlap(struct loopdev_cxt *lc, const char *filename,

 		if (rc) {

 			DBG(CXT, ul_debugobj(lc, "failed to get offset for device %s",

 				loopcxt_get_device(lc)));

-			break;

+			continue;

 		}

 		rc = loopcxt_get_sizelimit(lc, &lc_sizelimit);

 		if (rc) {

 			DBG(CXT, ul_debugobj(lc, "failed to get sizelimit for device %s",

 				loopcxt_get_device(lc)));

-			break;

+			continue;

 		}

 		/* full match */

-- 

2.37.1