Fix hfsplus oops on image without extents

Fix an oops with a corrupted hfs+ image.

See http://bugzilla.kernel.org/show_bug.cgi?id=10548 for details.

Problem is that we call hfs_btree_open() from hfsplus_fill_super() to set
HFSPLUS_SB(sb).[ext_tree|cat_tree] Both trees are still NULL at this moment.
If hfs_btree_open() fails for any reason it calls iput() on the page, which
gets to hfsplus_releasepage() which tries to access HFSPLUS_SB(sb).* which is
still NULL and oopses while dereferencing it.

[akpm@linux-foundation.org: build fix]
Signed-off-by: Eric Sesterhenn <snakebyte@gmx.de>
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>
This commit is contained in:
Eric Sesterhenn 2008-05-12 14:02:21 -07:00 committed by Linus Torvalds
parent 4413a0f637
commit 706322496b

View file

@ -65,6 +65,8 @@ static int hfsplus_releasepage(struct page *page, gfp_t mask)
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);