From: Zach Brown <zab@redhat.com>
Date: Wed, 23 Jan 2013 20:18:32 +0000 (-0800)
Subject: btrfs-progs: don't leak in set_extent_bits
X-Git-Tag: upstream/4.16.1~3459^2~21
X-Git-Url: http://review.tizen.org/git/?a=commitdiff_plain;h=09fac3824db462368f24d3dd4deccafedf5b3c8c;p=platform%2Fupstream%2Fbtrfs-progs.git

btrfs-progs: don't leak in set_extent_bits

It looks possible to hit the search_again label without using the
prealloc.  A new prealloc is allocated, leaking the current one.

Every use of prealloc sets it to null so let's just allocate a new
prealloc when we don't already have one.

Signed-off-by: Zach Brown <zab@redhat.com>
---

diff --git a/extent_io.c b/extent_io.c
index ebb35b2..d59f207 100644
--- a/extent_io.c
+++ b/extent_io.c
@@ -300,9 +300,11 @@ int set_extent_bits(struct extent_io_tree *tree, u64 start,
 	u64 last_start;
 	u64 last_end;
 again:
-	prealloc = alloc_extent_state();
-	if (!prealloc)
-		return -ENOMEM;
+	if (!prealloc) {
+		prealloc = alloc_extent_state();
+		if (!prealloc)
+			return -ENOMEM;
+	}
 
 	/*
 	 * this search will find the extents that end after