[PATCH] fix broken lib/genalloc.c
genalloc improperly stores the sizes of freed chunks, allocates overlapping
memory regions, and oopses after its in-band data is overwritten.
Signed-off-by: Chris Humbert <mahadri-kernel@drigon.com>
Cc: Jes Sorensen <jes@trained-monkey.org>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
diff --git a/lib/genalloc.c b/lib/genalloc.c
index d6d30d2e..9ce0a6a 100644
--- a/lib/genalloc.c
+++ b/lib/genalloc.c
@@ -95,12 +95,10 @@
if (size > max_chunk_size)
return 0;
- i = 0;
-
size = max(size, 1 << ALLOC_MIN_SHIFT);
- s = roundup_pow_of_two(size);
-
- j = i;
+ i = fls(size - 1);
+ s = 1 << i;
+ j = i -= ALLOC_MIN_SHIFT;
spin_lock_irqsave(&poolp->lock, flags);
while (!h[j].next) {
@@ -153,10 +151,10 @@
if (size > max_chunk_size)
return;
- i = 0;
-
size = max(size, 1 << ALLOC_MIN_SHIFT);
- s = roundup_pow_of_two(size);
+ i = fls(size - 1);
+ s = 1 << i;
+ i -= ALLOC_MIN_SHIFT;
a = ptr;