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From 68ef8adcff3acc25ddac82b808c3036b4dddaf0b Mon Sep 17 00:00:00 2001
From: Lukas Czerner <lczerner@redhat.com>
Date: Thu, 20 Feb 2014 14:14:39 +0100
Subject: [PATCH 8/8] e2fsprogs: Set pointer to NULL after ext2fs_free

ext2fs_free() does not set the ext2_filsys pointer to null so the caller
is responsible to setting it himself if it is needed.

This patch fixes some places where caller did not set ext2_filsys
pointer to NULL after ext2fs_free() which might result in use after
free. Fix it.

Signed-off-by: Lukas Czerner <lczerner@redhat.com>
---
 lib/ext2fs/openfs.c | 7 ++++---
 resize/resize2fs.c  | 5 ++++-
 2 files changed, 8 insertions(+), 4 deletions(-)

diff --git a/lib/ext2fs/openfs.c b/lib/ext2fs/openfs.c
index 4cdbde1..ef67493 100644
--- a/lib/ext2fs/openfs.c
+++ b/lib/ext2fs/openfs.c
@@ -419,10 +419,11 @@ errcode_t ext2fs_open2(const char *name, const char *io_options,
 
 	return 0;
 cleanup:
-	if (flags & EXT2_FLAG_NOFREE_ON_ERROR)
-		*ret_fs = fs;
-	else
+	if (!(flags & EXT2_FLAG_NOFREE_ON_ERROR)) {
 		ext2fs_free(fs);
+		fs = NULL;
+	}
+	*ret_fs = fs;
 	return retval;
 }
 
diff --git a/resize/resize2fs.c b/resize/resize2fs.c
index 6b32bbf..a1fdefa 100644
--- a/resize/resize2fs.c
+++ b/resize/resize2fs.c
@@ -202,6 +202,7 @@ errcode_t resize_fs(ext2_filsys fs, blk64_t *new_size, int flags,
 	rfs->flags = flags;
 
 	ext2fs_free(rfs->old_fs);
+	rfs->old_fs = NULL;
 	if (rfs->itable_buf)
 		ext2fs_free_mem(&rfs->itable_buf);
 	if (rfs->reserve_blocks)
@@ -213,8 +214,10 @@ errcode_t resize_fs(ext2_filsys fs, blk64_t *new_size, int flags,
 	return 0;
 
 errout:
-	if (rfs->new_fs)
+	if (rfs->new_fs) {
 		ext2fs_free(rfs->new_fs);
+		rfs->new_fs = NULL;
+	}
 	if (rfs->itable_buf)
 		ext2fs_free_mem(&rfs->itable_buf);
 	ext2fs_free_mem(&rfs);
-- 
1.8.3.1