From 3091c21d3e9322428691ce0b7a0cfa9c0b239eeb Mon Sep 17 00:00:00 2001 From: Carlos Llamas Date: Fri, 1 Dec 2023 17:21:33 +0000 Subject: binder: fix async space check for 0-sized buffers Move the padding of 0-sized buffers to an earlier stage to account for this round up during the alloc->free_async_space check. Fixes: 74310e06be4d ("android: binder: Move buffer out of area shared with user space") Reviewed-by: Alice Ryhl Signed-off-by: Carlos Llamas Link: https://lore.kernel.org/r/20231201172212.1813387-5-cmllamas@google.com Signed-off-by: Greg Kroah-Hartman --- drivers/android/binder_alloc.c | 7 ++++--- 1 file changed, 4 insertions(+), 3 deletions(-) (limited to 'drivers/android') diff --git a/drivers/android/binder_alloc.c b/drivers/android/binder_alloc.c index adcec5ec0959..abff1bafcc43 100644 --- a/drivers/android/binder_alloc.c +++ b/drivers/android/binder_alloc.c @@ -407,6 +407,10 @@ static struct binder_buffer *binder_alloc_new_buf_locked( alloc->pid, extra_buffers_size); return ERR_PTR(-EINVAL); } + + /* Pad 0-size buffers so they get assigned unique addresses */ + size = max(size, sizeof(void *)); + if (is_async && alloc->free_async_space < size + sizeof(struct binder_buffer)) { binder_alloc_debug(BINDER_DEBUG_BUFFER_ALLOC, @@ -415,9 +419,6 @@ static struct binder_buffer *binder_alloc_new_buf_locked( return ERR_PTR(-ENOSPC); } - /* Pad 0-size buffers so they get assigned unique addresses */ - size = max(size, sizeof(void *)); - while (n) { buffer = rb_entry(n, struct binder_buffer, rb_node); BUG_ON(!buffer->free); -- cgit