hfs: fix memory leak when unmounting
When an HFS filesystem is unmounted, it leaks a 2-page bitmap. Also,
under extreme memory pressure, it's possible that hfs_releasepage() may
use a tree pointer that has not been initialized, and if so, the release
request should just be rejected.
[akpm@linux-foundation.org: free_pages(0) is legal, remove obvious comment]
Signed-off-by: Dave Anderson <anderson@redhat.com>
Tested-by: Eugene Teo <eugeneteo@kernel.sg>
Cc: Roman Zippel <zippel@linux-m68k.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
diff --git a/fs/hfs/inode.c b/fs/hfs/inode.c
index 9435dda..a1cbff2 100644
--- a/fs/hfs/inode.c
+++ b/fs/hfs/inode.c
@@ -70,6 +70,10 @@
BUG();
return 0;
}
+
+ if (!tree)
+ return 0;
+
if (tree->node_size >= PAGE_CACHE_SIZE) {
nidx = page->index >> (tree->node_size_shift - PAGE_CACHE_SHIFT);
spin_lock(&tree->hash_lock);