kernel/linux.git/drivers/android/binder/process.rs, branch v7.1-rc6

rust_binder: Avoid holding lock when dropping delivered_death

2026-05-22T09:55:48+00:00

In 6c37bebd8c926, we switched to looping over the list and dropping each individual node, ostensibly without the lock held in the loop body. If the kernel were using Rust Edition 2024, the comment would be accurate, and the lock would not be held across the drop. However, the kernel is currently using 2021, so tail expression lifetime extension results in the lock being held across the drop. Explicitly binding the expression result to a variable makes the lockguard no longer part of a tail expression, causing the lock to be dropped before entering the loop body. This was detected via `CONFIG_PROVE_LOCKING` identifying an invalid wait context at the drop site. Reported-by: David Stevens Signed-off-by: Matthew Maurer Cc: stable Fixes: 6c37bebd8c92 ("rust_binder: avoid mem::take on delivered_deaths") Reviewed-by: Alice Ryhl Acked-by: Carlos Llamas Link: https://patch.msgid.link/20260403-lockhold-v1-1-c332b56cd8ae@google.com Signed-off-by: Greg Kroah-Hartman

rust_binder: add ioctl/read/write done tracepoints

2026-04-01T10:18:22+00:00

Add Rust Binder tracepoints declarations for `ioctl_done`, `read_done` and `write_done`. Additionally, wire in the new tracepoints into the corresponding Binder call sites. Note that the new tracepoints report final errno-style return values, matching the existing C model for operation completion. Signed-off-by: Mohamad Alsadhan Link: https://patch.msgid.link/20260317-rust-binder-trace-v3-2-6fae4fbcf637@sdhn.cc Signed-off-by: Greg Kroah-Hartman

rust_binder: make use of == for Task

2026-04-01T10:18:21+00:00

Now that we have implemented the == operator for Task, replace the two raw pointer comparisons in Binder with the == operator. Reviewed-by: Gary Guo Signed-off-by: Alice Ryhl Link: https://patch.msgid.link/20260324-close-fd-check-current-v3-3-b94274bedac7@google.com Signed-off-by: Greg Kroah-Hartman

rust_binder: introduce TransactionInfo

2026-03-31T13:13:56+00:00

Rust Binder exposes information about transactions that are sent in various ways: printing to the kernel log, tracepoints, files in binderfs, and the upcoming netlink support. Currently all these mechanisms use disparate ways of obtaining the same information, so let's introduce a single Info struct that collects all the required information in a single place, so that all of these different mechanisms can operate in a more uniform way. For now, the new info struct is only used to replace a few things: * The BinderTransactionDataSg struct that is passed as an argument to several methods is removed as the information is moved into the new info struct and passed down that way. * The oneway spam detection fields on Transaction and Allocation can be removed, as the information can be returned to the caller via the mutable info struct instead. But several other uses of the info struct are planned in follow-up patches. Signed-off-by: Alice Ryhl Link: https://patch.msgid.link/20260306-transaction-info-v1-1-fda58fca558b@google.com Signed-off-by: Greg Kroah-Hartman

Merge 7.0-rc4 into char-misc-next

2026-03-16T10:41:58+00:00

We need the char/misc/iio fixes in this branch as well to build on top of. Signed-off-by: Greg Kroah-Hartman

rust_binder: avoid name mangling for get_work[_local]

2026-02-27T05:34:54+00:00

Currently ps -A shows processes waiting on schedule() in functions with names such as do_epoll_wait, wait_woken, and the impeccably named _RNvMs2_NtCs8QPsHWIn21X_16rust_binder_main6threadNtB5_6Thread8get_work. To improve how ps output looks, give explicit non-mangled names to the functions where Rust Binder calls schedule(), since these are the most likely places to show up on ps output. The name of rust_binder_waitlcl is truncated instead of using _local suffix because rust_binder_wait_local is sufficiently long that ps shows unaligned output. This is intended to be a temporary workaround until we find a better solution. Adding #[export_name] to every Rust function that calls schedule() is not a great long-term solution. Suggested-by: Matthew Maurer Signed-off-by: Alice Ryhl Acked-by: Gary Guo Link: https://patch.msgid.link/20260219-rust-binder-ps-v2-1-773eca09c125@google.com Signed-off-by: Greg Kroah-Hartman

rust_binder: call set_notification_done() without proc lock

2026-02-27T05:33:03+00:00

Consider the following sequence of events on a death listener: 1. The remote process dies and sends a BR_DEAD_BINDER message. 2. The local process invokes the BC_CLEAR_DEATH_NOTIFICATION command. 3. The local process then invokes the BC_DEAD_BINDER_DONE. Then, the kernel will reply to the BC_DEAD_BINDER_DONE command with a BR_CLEAR_DEATH_NOTIFICATION_DONE reply using push_work_if_looper(). However, this can result in a deadlock if the current thread is not a looper. This is because dead_binder_done() still holds the proc lock during set_notification_done(), which called push_work_if_looper(). Normally, push_work_if_looper() takes the thread lock, which is fine to take under the proc lock. But if the current thread is not a looper, then it falls back to delivering the reply to the process work queue, which involves taking the proc lock. Since the proc lock is already held, this is a deadlock. Fix this by releasing the proc lock during set_notification_done(). It was not intentional that it was held during that function to begin with. I don't think this ever happens in Android because BC_DEAD_BINDER_DONE is only invoked in response to BR_DEAD_BINDER messages, and the kernel always delivers BR_DEAD_BINDER to a looper. So there's no scenario where Android userspace will call BC_DEAD_BINDER_DONE on a non-looper thread. Cc: stable Fixes: eafedbc7c050 ("rust_binder: add Rust Binder driver") Reported-by: syzbot+c8287e65a57a89e7fb72@syzkaller.appspotmail.com Tested-by: syzbot+c8287e65a57a89e7fb72@syzkaller.appspotmail.com Signed-off-by: Alice Ryhl Reviewed-by: Gary Guo Reviewed-by: Andreas Hindborg Link: https://patch.msgid.link/20260224-binder-dead-binder-done-proc-lock-v1-1-bbe1b8a6e74a@google.com Signed-off-by: Greg Kroah-Hartman

drivers: android: binder: Update ARef imports from sync::aref

2026-02-03T11:58:36+00:00

Update call sites in binder files to import `ARef` from `sync::aref` instead of `types`. This aligns with the ongoing effort to move `ARef` and `AlwaysRefCounted` to sync. Suggested-by: Benno Lossin Link: https://github.com/Rust-for-Linux/linux/issues/1173 Signed-off-by: Shankari Anand Acked-by: Alice Ryhl Link: https://patch.msgid.link/20260102202714.184223-2-shankari.ak0208@gmail.com Signed-off-by: Greg Kroah-Hartman

rust_binder: refactor context management to use KVVec

2026-01-26T15:18:41+00:00

Replace the linked list management in context.rs with KVVec. This simplifies the ownership model by using standard Arc-based tracking and moves away from manual unsafe list removals. The refactor improves memory safety by leveraging Rust's contiguous collection types while maintaining proper error propagation for allocation failures during process registration. Suggested-by: Alice Ryhl Link: https://github.com/rust-for-linux/linux/issues/1215 Signed-off-by: Jason Hall Link: https://patch.msgid.link/20260120134119.98048-1-jason.kei.hall@gmail.com Signed-off-by: Greg Kroah-Hartman

rust_binder: add binder_transaction tracepoint

2025-12-29T11:14:52+00:00

This patch adds the binder_transaction tracepoint to Rust Binder. This was chosen as the next tracepoint to add as it is the most complex tracepoint. (And it's also an important tracepoint known to perfetto.) Signed-off-by: Alice Ryhl Link: https://patch.msgid.link/20251203-binder-trace1-v1-2-22d3ffddb44e@google.com Signed-off-by: Greg Kroah-Hartman