Revert "binder: fix UAF caused by faulty buffer cleanup"

This reverts commit e1e198eff1.

It breaks the Android KABI and will be brought back at a later time when
it is safe to do so.

Bug: 161946584
Change-Id: I66f4d99f9adce21b7eb4a78cb6775f1df69a4343
Signed-off-by: Greg Kroah-Hartman <gregkh@google.com>
This commit is contained in:
Greg Kroah-Hartman 2023-06-13 19:37:40 +00:00
parent 940f3dad8f
commit 9f67f4f500

View File

@ -2126,23 +2126,24 @@ static void binder_deferred_fd_close(int fd)
static void binder_transaction_buffer_release(struct binder_proc *proc,
struct binder_thread *thread,
struct binder_buffer *buffer,
binder_size_t off_end_offset,
binder_size_t failed_at,
bool is_failure)
{
int debug_id = buffer->debug_id;
binder_size_t off_start_offset, buffer_offset;
binder_size_t off_start_offset, buffer_offset, off_end_offset;
binder_debug(BINDER_DEBUG_TRANSACTION,
"%d buffer release %d, size %zd-%zd, failed at %llx\n",
proc->pid, buffer->debug_id,
buffer->data_size, buffer->offsets_size,
(unsigned long long)off_end_offset);
(unsigned long long)failed_at);
if (buffer->target_node)
binder_dec_node(buffer->target_node, 1, 0);
off_start_offset = ALIGN(buffer->data_size, sizeof(void *));
off_end_offset = is_failure && failed_at ? failed_at :
off_start_offset + buffer->offsets_size;
for (buffer_offset = off_start_offset; buffer_offset < off_end_offset;
buffer_offset += sizeof(binder_size_t)) {
struct binder_object_header *hdr;
@ -2302,21 +2303,6 @@ static void binder_transaction_buffer_release(struct binder_proc *proc,
}
}
/* Clean up all the objects in the buffer */
static inline void binder_release_entire_buffer(struct binder_proc *proc,
struct binder_thread *thread,
struct binder_buffer *buffer,
bool is_failure)
{
binder_size_t off_end_offset;
off_end_offset = ALIGN(buffer->data_size, sizeof(void *));
off_end_offset += buffer->offsets_size;
binder_transaction_buffer_release(proc, thread, buffer,
off_end_offset, is_failure);
}
static int binder_translate_binder(struct flat_binder_object *fp,
struct binder_transaction *t,
struct binder_thread *thread)
@ -3019,7 +3005,7 @@ static int binder_proc_transaction(struct binder_transaction *t,
t_outdated->buffer = NULL;
buffer->transaction = NULL;
trace_binder_transaction_update_buffer_release(buffer);
binder_release_entire_buffer(proc, NULL, buffer, false);
binder_transaction_buffer_release(proc, NULL, buffer, 0, 0);
binder_alloc_free_buf(&proc->alloc, buffer);
kfree(t_outdated);
binder_stats_deleted(BINDER_STAT_TRANSACTION);
@ -4004,7 +3990,7 @@ binder_free_buf(struct binder_proc *proc,
binder_node_inner_unlock(buf_node);
}
trace_binder_transaction_buffer_release(buffer);
binder_release_entire_buffer(proc, thread, buffer, is_failure);
binder_transaction_buffer_release(proc, thread, buffer, 0, is_failure);
binder_alloc_free_buf(&proc->alloc, buffer);
}