4.19-stable review patch. If anyone has any objections, please let me know.
------------------
From: Carlos Llamas <cmllamas@xxxxxxxxxx>
commit 3091c21d3e9322428691ce0b7a0cfa9c0b239eeb upstream.
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 <aliceryhl@xxxxxxxxxx>
Signed-off-by: Carlos Llamas <cmllamas@xxxxxxxxxx>
Link: https://lore.kernel.org/r/20231201172212.1813387-5-cmllamas@xxxxxxxxxx
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
drivers/android/binder_alloc.c | 7 ++++---
1 file changed, 4 insertions(+), 3 deletions(-)
--- a/drivers/android/binder_alloc.c
+++ b/drivers/android/binder_alloc.c
@@ -398,6 +398,10 @@ static struct binder_buffer *binder_allo
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,
@@ -406,9 +410,6 @@ static struct binder_buffer *binder_allo
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);
