kernel/linux.git/drivers/android/binder, branch v6.18.39

rust_binder: fix BINDER_GET_EXTENDED_ERROR

2026-07-18T14:53:25+00:00

[ Upstream commit 77bfebf110773f5a0d6b5ff8110896adb2c9c335 ] This code currently copies the ExtendedError struct to the stack, modifies the copy, and then doesn't modify the original. Thus, fix it. Furthermore, errors when replying must be delivered directly to the remote thread, so update deliver_reply() to take an extended error argument. Cc: stable Fixes: eafedbc7c050 ("rust_binder: add Rust Binder driver") Signed-off-by: Alice Ryhl Acked-by: Carlos Llamas Link: https://patch.msgid.link/20260605-set-extended-error-v3-1-d60b69a75f97@google.com Signed-off-by: Greg Kroah-Hartman Signed-off-by: Alice Ryhl Signed-off-by: Sasha Levin

rust_binder: introduce TransactionInfo

2026-07-18T14:53:25+00:00

[ Upstream commit 5326a18e3e640061ca4b65c1b732feaeace61c39 ] 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 [aliceryhl: explicitly impl Zeroable for UserPtr instead of using derive] Signed-off-by: Alice Ryhl Signed-off-by: Sasha Levin

rust_binder: clear freeze listener on node removal

2026-07-18T14:53:12+00:00

commit bc4a9828897871ff3e5a1f8a1d346decbf4ee95e upstream. Generally userspace is supposed to explicitly clear freeze listeners before they drop the refcount on the node ref to zero, but there's nothing forcing that. Currently, in this scenario the freeze listener remains in the freeze_listeners rbtree and in the remote node's freeze listener list, even though the ref for which the listener is registered is gone. This could potentially lead to a memory leak due to a refcount cycle. Thus, remove the freeze listener in this scenario. Cc: stable Fixes: eafedbc7c050 ("rust_binder: add Rust Binder driver") Signed-off-by: Alice Ryhl Link: https://patch.msgid.link/20260703-remove-freeze-on-remove-node-v3-1-6e0c4547af46@google.com Signed-off-by: Greg Kroah-Hartman

rust_binder: synchronize Rust Binder stats with freeze commands

2026-07-18T14:53:12+00:00

commit eb1645bf10190e71f6f0316e37ff70755d719b53 upstream. Rust Binder stats use BC_COUNT and BR_COUNT to size the command and return counters, and use event string tables when printing debug statistics. The Binder protocol includes freeze-related commands and return codes, but the Rust Binder statistics code was not updated to cover them. As a result, those commands and return codes are not accounted for or printed by the stats debug output. Update the counts and event string tables so these commands and return codes are included in the debug statistics output. Fixes: eafedbc7c050 ("rust_binder: add Rust Binder driver") Cc: stable Acked-by: Carlos Llamas Reviewed-by: Alice Ryhl Signed-off-by: Keshav Verma Link: https://patch.msgid.link/20260615211743.734-1-iganschel@gmail.com Signed-off-by: Greg Kroah-Hartman Signed-off-by: Greg Kroah-Hartman

rust_binder: reject context manager self-transaction

2026-07-18T14:53:12+00:00

commit 6849cabfd30fb5727cfd31e8241e15801e17ebf9 upstream. 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 Signed-off-by: Greg Kroah-Hartman

rust_binder: use a u64 stride when cleaning up the offsets array

2026-07-18T14:53:11+00:00

commit 803c8a9502e9b97cd6ae937618ef4a8fd6274343 upstream. Allocation's Drop walks the offsets array (binder_size_t = u64 entries), cleaning up the objects, but it used usize instead of u64 for both the stride and the per-entry read. On 64-bit kernels (usize == u64) this is harmless, but on 32-bit kernels it walks the 8-byte entries in 4-byte steps, iterating an N-entry array 2N times, and reads the always-zero high word as offset 0, cleaning up the object at offset 0 N extra times. As a result the referenced node or handle ends up with a lower reference count than it actually has (a refcount over-decrement), and binder's reference accounting is corrupted; for example, the owner can be notified of a strong reference release (BR_RELEASE) even though references still remain. Change the stride to u64, and read each entry as a u64, narrowing it to usize with try_into(). On 32-bit ARM, when this over-decrement would drive a count below zero, the driver's existing refcount guard refuses it and fires: rust_binder: Failure: refcount underflow! Cc: stable Fixes: eafedbc7c050 ("rust_binder: add Rust Binder driver") Signed-off-by: Hyunwoo Kim Acked-by: Carlos Llamas Reviewed-by: Alice Ryhl Link: https://patch.msgid.link/ahw3tFhLz9bMMJAO@v4bel Signed-off-by: Greg Kroah-Hartman

rust_binder: avoid calling pending_oneway_finished() on TF_UPDATE_TXN

2026-06-09T10:28:36+00:00

commit 4c19719eb8b8df08c5bec7c499f73ddaea6f09fc upstream. When an outdated transaction is removed from `oneway_todo` due to `TF_UPDATE_TXN`, its `Allocation` is dropped. The current implementation of `Allocation::drop` calls `pending_oneway_finished()`, assuming the transaction was executed. This leads to premature execution of the next queued one-way transaction. Fix this by taking the `oneway_node` from the `Allocation` of the outdated transaction before it is dropped. This prevents `Allocation::drop` from signaling completion. We do not call `take_oneway_node()` from `Transaction::cancel` because it's actually correct to call `pending_oneway_finished()` on cancel if the transaction did not come from `oneway_todo`. This ensures that if `BINDER_THREAD_EXIT` is invoked and cancels a oneway transaction, then the next transaction is taken from `oneway_todo`. This bug does not lead to any issues in the kernel, but may lead to Binder delivering transactions to userspace earlier than userspace expected to receive them. Cc: stable Fixes: eafedbc7c050 ("rust_binder: add Rust Binder driver") Assisted-by: Antigravity:gemini Signed-off-by: Alice Ryhl Acked-by: Carlos Llamas Link: https://patch.msgid.link/20260414-tf-update-txn-fix-v1-1-d2b83303acc9@google.com Signed-off-by: Greg Kroah-Hartman Signed-off-by: Greg Kroah-Hartman

rust_binder: Avoid holding lock when dropping delivered_death

2026-06-09T10:28:35+00:00

commit f6d8fea9e3953151a4adb4f603503dc3dc9c69da upstream. 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 Signed-off-by: Greg Kroah-Hartman

rust: allow `clippy::collapsible_if` globally

2026-05-14T13:30:15+00:00

commit 2adc8664018c1cc595c7c0c98474a33c7fe32a85 upstream. Similar to `clippy::collapsible_match` (globally allowed in the previous commit), the `clippy::collapsible_if` lint [1] can make code harder to read in certain cases. Thus just let developers decide on their own. In addition, remove the existing `expect` we had. Cc: stable@vger.kernel.org # Needed in 6.12.y and later (Rust is pinned in older LTSs). Suggested-by: Gary Guo Link: https://lore.kernel.org/rust-for-linux/DGROP5CHU1QZ.1OKJRAUZXE9WC@garyguo.net/ Link: https://rust-lang.github.io/rust-clippy/master/index.html#collapsible_if [1] Reviewed-by: Gary Guo Link: https://patch.msgid.link/20260426144201.227108-2-ojeda@kernel.org Signed-off-by: Miguel Ojeda Signed-off-by: Greg Kroah-Hartman

rust_binder: use AssertSync for BINDER_VM_OPS

2026-04-11T12:26:33+00:00

commit ec327abae5edd1d5b60ea9f920212970133171d2 upstream. When declaring an immutable global variable in Rust, the compiler checks that it looks thread safe, because it is generally safe to access said global variable. When using C bindings types for these globals, we don't really want this check, because it is conservative and assumes pointers are not thread safe. In the case of BINDER_VM_OPS, this is a challenge when combined with the patch 'userfaultfd: introduce vm_uffd_ops' [1], which introduces a pointer field to vm_operations_struct. It previously only held function pointers, which are considered thread safe. Rust Binder should not be assuming that vm_operations_struct contains no pointer fields, so to fix this, use AssertSync (which Rust Binder has already declared for another similar global of type struct file_operations with the same problem). This ensures that even if another commit adds a pointer field to vm_operations_struct, this does not cause problems. Fixes: 8ef2c15aeae0 ("rust_binder: check ownership before using vma") Cc: stable Reported-by: kernel test robot Closes: https://lore.kernel.org/oe-kbuild-all/202603121235.tpnRxFKO-lkp@intel.com/ Link: https://lore.kernel.org/r/20260306171815.3160826-8-rppt@kernel.org [1] Signed-off-by: Alice Ryhl Reviewed-by: Gary Guo Link: https://patch.msgid.link/20260314111951.4139029-1-aliceryhl@google.com Signed-off-by: Greg Kroah-Hartman