diff options
Diffstat (limited to 'kernel/drivers/android')
| -rw-r--r-- | kernel/drivers/android/binder.c | 35 |
1 files changed, 26 insertions, 9 deletions
diff --git a/kernel/drivers/android/binder.c b/kernel/drivers/android/binder.c index 7d00b7a01..47ddfefe2 100644 --- a/kernel/drivers/android/binder.c +++ b/kernel/drivers/android/binder.c @@ -1003,7 +1003,7 @@ static int binder_dec_node(struct binder_node *node, int strong, int internal) static struct binder_ref *binder_get_ref(struct binder_proc *proc, - uint32_t desc) + u32 desc, bool need_strong_ref) { struct rb_node *n = proc->refs_by_desc.rb_node; struct binder_ref *ref; @@ -1011,12 +1011,16 @@ static struct binder_ref *binder_get_ref(struct binder_proc *proc, while (n) { ref = rb_entry(n, struct binder_ref, rb_node_desc); - if (desc < ref->desc) + if (desc < ref->desc) { n = n->rb_left; - else if (desc > ref->desc) + } else if (desc > ref->desc) { n = n->rb_right; - else + } else if (need_strong_ref && !ref->strong) { + binder_user_error("tried to use weak ref as strong ref\n"); + return NULL; + } else { return ref; + } } return NULL; } @@ -1286,7 +1290,10 @@ static void binder_transaction_buffer_release(struct binder_proc *proc, } break; case BINDER_TYPE_HANDLE: case BINDER_TYPE_WEAK_HANDLE: { - struct binder_ref *ref = binder_get_ref(proc, fp->handle); + struct binder_ref *ref; + + ref = binder_get_ref(proc, fp->handle, + fp->type == BINDER_TYPE_HANDLE); if (ref == NULL) { pr_err("transaction release %d bad handle %d\n", @@ -1380,7 +1387,7 @@ static void binder_transaction(struct binder_proc *proc, if (tr->target.handle) { struct binder_ref *ref; - ref = binder_get_ref(proc, tr->target.handle); + ref = binder_get_ref(proc, tr->target.handle, true); if (ref == NULL) { binder_user_error("%d:%d got transaction to invalid handle\n", proc->pid, thread->pid); @@ -1571,7 +1578,9 @@ static void binder_transaction(struct binder_proc *proc, fp->type = BINDER_TYPE_HANDLE; else fp->type = BINDER_TYPE_WEAK_HANDLE; + fp->binder = 0; fp->handle = ref->desc; + fp->cookie = 0; binder_inc_ref(ref, fp->type == BINDER_TYPE_HANDLE, &thread->todo); @@ -1583,7 +1592,10 @@ static void binder_transaction(struct binder_proc *proc, } break; case BINDER_TYPE_HANDLE: case BINDER_TYPE_WEAK_HANDLE: { - struct binder_ref *ref = binder_get_ref(proc, fp->handle); + struct binder_ref *ref; + + ref = binder_get_ref(proc, fp->handle, + fp->type == BINDER_TYPE_HANDLE); if (ref == NULL) { binder_user_error("%d:%d got transaction with invalid handle, %d\n", @@ -1618,7 +1630,9 @@ static void binder_transaction(struct binder_proc *proc, return_error = BR_FAILED_REPLY; goto err_binder_get_ref_for_node_failed; } + fp->binder = 0; fp->handle = new_ref->desc; + fp->cookie = 0; binder_inc_ref(new_ref, fp->type == BINDER_TYPE_HANDLE, NULL); trace_binder_transaction_ref_to_ref(t, ref, new_ref); @@ -1672,6 +1686,7 @@ static void binder_transaction(struct binder_proc *proc, binder_debug(BINDER_DEBUG_TRANSACTION, " fd %d -> %d\n", fp->handle, target_fd); /* TODO: fput? */ + fp->binder = 0; fp->handle = target_fd; } break; @@ -1794,7 +1809,9 @@ static int binder_thread_write(struct binder_proc *proc, ref->desc); } } else - ref = binder_get_ref(proc, target); + ref = binder_get_ref(proc, target, + cmd == BC_ACQUIRE || + cmd == BC_RELEASE); if (ref == NULL) { binder_user_error("%d:%d refcount change on invalid ref %d\n", proc->pid, thread->pid, target); @@ -1990,7 +2007,7 @@ static int binder_thread_write(struct binder_proc *proc, if (get_user(cookie, (binder_uintptr_t __user *)ptr)) return -EFAULT; ptr += sizeof(binder_uintptr_t); - ref = binder_get_ref(proc, target); + ref = binder_get_ref(proc, target, false); if (ref == NULL) { binder_user_error("%d:%d %s invalid ref %d\n", proc->pid, thread->pid, |