From: Harshad Shirwadkar <harshadshirwadkar@gmail.com>
Date: Wed, 17 Nov 2021 16:50:15 +0000 (-0800)
Subject: e2fsck: skip sorting extents if there are no valid extents
X-Git-Tag: v1.46.5~14
X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=54183fea07676d185b2c169c45a7c1adc7e3e26e;p=thirdparty%2Fe2fsprogs.git

e2fsck: skip sorting extents if there are no valid extents

At the end of a fast commit replay, e2fsck tries merging extents in a
inode. This patch fixes a bug in this logic where we were continuing
this action even if there were no extents to merge resulting in
accessing illegal memory.

Signed-off-by: Harshad Shirwadkar <harshadshirwadkar@gmail.com>
---

diff --git a/e2fsck/journal.c b/e2fsck/journal.c
index fe4e018df..2e867234b 100644
--- a/e2fsck/journal.c
+++ b/e2fsck/journal.c
@@ -464,6 +464,9 @@ static void ex_sort_and_merge(struct extent_list *list)
 		}
 	}
 
+	if (list->count == 0)
+		return;
+
 	/* Now sort by logical offset */
 	qsort(list->extents, list->count, sizeof(list->extents[0]),
 		ex_compar);