From 6849cabfd30fb5727cfd31e8241e15801e17ebf9 Mon Sep 17 00:00:00 2001 From: Keshav Verma Date: Thu, 25 Jun 2026 16:09:57 +0530 Subject: [PATCH] rust_binder: reject context manager self-transaction Rust binder resolved handle 0 to the context manager node, but it does not reject the case where the caller owns the same node. The C binder driver rejects transactions from the context-manager process to handle 0 after resolving the target node. Match that behavior in Rust Binder by rejecting handle 0 transactions when the resolved context-manager node is owned by the calling process. This applies to both synchronous and oneway transactions because both paths resolve the target through Process::get_transaction_node(). Cc: stable Fixes: eafedbc7c050 ("rust_binder: add Rust Binder driver") Signed-off-by: Keshav Verma Reviewed-by: Alice Ryhl Link: https://patch.msgid.link/20260625103957.730-1-iganschel@gmail.com Signed-off-by: Greg Kroah-Hartman --- drivers/android/binder/process.rs | 6 +++++- 1 file changed, 5 insertions(+), 1 deletion(-) diff --git a/drivers/android/binder/process.rs b/drivers/android/binder/process.rs index 96b8440ceac6..ca664fda8e81 100644 --- a/drivers/android/binder/process.rs +++ b/drivers/android/binder/process.rs @@ -900,7 +900,11 @@ impl Process { pub(crate) fn get_transaction_node(&self, handle: u32) -> BinderResult { // When handle is zero, try to get the context manager. if handle == 0 { - Ok(self.ctx.get_manager_node(true)?) + let node_ref = self.ctx.get_manager_node(true)?; + if core::ptr::eq(self, &*node_ref.node.owner) { + return Err(EINVAL.into()); + } + Ok(node_ref) } else { Ok(self.get_node_from_handle(handle, true)?) } -- 2.47.3