From d49c95c944c15732ef57f1c876e24838b2ddf34b Mon Sep 17 00:00:00 2001 From: Todd Kjos Date: Tue, 19 Mar 2019 09:53:01 -0700 Subject: [PATCH] binder: fix BUG_ON found by selinux-testsuite The selinux-testsuite found an issue resulting in a BUG_ON() where a conditional relied on a size_t going negative when checking the validity of a buffer offset. Fixes: 7a67a39320df ("binder: add function to copy binder object from buffer") Reported-by: Paul Moore Tested-by: Paul Moore Signed-off-by: Todd Kjos --- Please add to 5.1 (fixes problem introduced in 5.1-rc1) drivers/android/binder.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) diff --git a/drivers/android/binder.c b/drivers/android/binder.c index 8685882da64cd..4b9c7ca492e6d 100644 --- a/drivers/android/binder.c +++ b/drivers/android/binder.c @@ -2057,7 +2057,8 @@ static size_t binder_get_object(struct binder_proc *proc, size_t object_size = 0; read_size = min_t(size_t, sizeof(*object), buffer->data_size - offset); - if (read_size < sizeof(*hdr) || !IS_ALIGNED(offset, sizeof(u32))) + if (offset > buffer->data_size || read_size < sizeof(*hdr) || + !IS_ALIGNED(offset, sizeof(u32))) return 0; binder_alloc_copy_from_buffer(&proc->alloc, object, buffer, offset, read_size); -- 2.21.0.225.g810b269d1ac-goog