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authorLinus Torvalds <torvalds@linux-foundation.org>2026-10-02 12:17:24 -0700
committerLinus Torvalds <torvalds@linux-foundation.org>2026-10-02 12:17:24 -0700
commit3f1fe48a36b0b6722dc3fd421d93512bac138e9a (patch)
treeb767d7f6e26bc64334d3f14f8422d187239dc45d /rust/syn/drops.rs
downloadlinux-stable-3f1fe48a36b0b6722dc3fd421d93512bac138e9a.tar.gz
linux-stable-3f1fe48a36b0b6722dc3fd421d93512bac138e9a.zip
Merge tag 'io_uring-7.3-20261002' of git://git.kernel.org/pub/scm/linux/kernel/git/axboe/linuxgrafted
Pull io_uring fixes from Jens Axboe: - Fix a task_work add use-after-free with SQPOLL. The sqpoll thread could pop and complete the last request while io_req_normal_work_add() was still looking at them after the mpscq push. Use the same approach as DEFER_TASKRUN to protect from that, holding an RCU read lock across the add, and have exit wait for an RCU grace period for SQPOLL rings as well. - CQE32 ring fixes: correct the free entry check for 32b CQEs, zero the big_cqe for aux CQEs, and only post the dummy skip CQE on CQE_MIXED rings - Mark the source filter table as COW when cloning bpf filters, so registering another filter on the source doesn't modify the shared table in place - Initialize the task context before running the BPF loop - Requeue zcrx multishot receives stopped by a local resource - End a TX_TIMESTAMP multishot cmd when the CQ is full (lollipopkit) * tag 'io_uring-7.3-20261002' of git://git.kernel.org/pub/scm/linux/kernel/git/axboe/linux: io_uring: fix task_work add use-after-free with SQPOLL io_uring/cmd_net: end TX_TIMESTAMP multishot when the CQ is full io_uring/zcrx: requeue multishot receives stopped by a local resource io_uring: initialize task context before running the BPF loop io_uring: zero big_cqe for aux CQEs on CQE32 rings io_uring: fix free entry check for 32b CQEs on CQE32 rings io_uring: only post the dummy skip CQE on CQE_MIXED rings io_uring/bpf_filter: mark source as COW when cloning filters
Diffstat (limited to 'rust/syn/drops.rs')
-rw-r--r--rust/syn/drops.rs60
1 files changed, 60 insertions, 0 deletions
diff --git a/rust/syn/drops.rs b/rust/syn/drops.rs
new file mode 100644
index 000000000..2c4ae333d
--- /dev/null
+++ b/rust/syn/drops.rs
@@ -0,0 +1,60 @@
+// SPDX-License-Identifier: Apache-2.0 OR MIT
+
+use std::iter;
+use std::mem::ManuallyDrop;
+use std::ops::{Deref, DerefMut};
+use std::option;
+use std::slice;
+
+#[repr(transparent)]
+pub(crate) struct NoDrop<T: ?Sized>(ManuallyDrop<T>);
+
+impl<T> NoDrop<T> {
+ pub(crate) fn new(value: T) -> Self
+ where
+ T: TrivialDrop,
+ {
+ NoDrop(ManuallyDrop::new(value))
+ }
+}
+
+impl<T: ?Sized> Deref for NoDrop<T> {
+ type Target = T;
+ fn deref(&self) -> &Self::Target {
+ &self.0
+ }
+}
+
+impl<T: ?Sized> DerefMut for NoDrop<T> {
+ fn deref_mut(&mut self) -> &mut Self::Target {
+ &mut self.0
+ }
+}
+
+pub(crate) trait TrivialDrop {}
+
+impl<T> TrivialDrop for iter::Empty<T> {}
+impl<T> TrivialDrop for slice::Iter<'_, T> {}
+impl<T> TrivialDrop for slice::IterMut<'_, T> {}
+impl<T> TrivialDrop for option::IntoIter<&T> {}
+impl<T> TrivialDrop for option::IntoIter<&mut T> {}
+
+#[test]
+fn test_needs_drop() {
+ use std::mem::needs_drop;
+
+ struct NeedsDrop;
+
+ impl Drop for NeedsDrop {
+ fn drop(&mut self) {}
+ }
+
+ assert!(needs_drop::<NeedsDrop>());
+
+ // Test each of the types with a handwritten TrivialDrop impl above.
+ assert!(!needs_drop::<iter::Empty<NeedsDrop>>());
+ assert!(!needs_drop::<slice::Iter<NeedsDrop>>());
+ assert!(!needs_drop::<slice::IterMut<NeedsDrop>>());
+ assert!(!needs_drop::<option::IntoIter<&NeedsDrop>>());
+ assert!(!needs_drop::<option::IntoIter<&mut NeedsDrop>>());
+}