5.4-stable review patch. If anyone has any objections, please let me know.
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From: Carlos Llamas cmllamas@google.com
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@google.com Signed-off-by: Carlos Llamas cmllamas@google.com Link: https://lore.kernel.org/r/20231201172212.1813387-5-cmllamas@google.com Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org --- 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 @@ -378,6 +378,10 @@ 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, @@ -386,9 +390,6 @@ 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);