From 8ad1a41f7e23287f07a3516c700bc32501d4f104 Mon Sep 17 00:00:00 2001 From: Alice Ryhl Date: Sun, 15 Sep 2024 14:31:33 +0000 Subject: rust: file: add `Kuid` wrapper Adds a wrapper around `kuid_t` called `Kuid`. This allows us to define various operations on kuids such as equality and current_euid. It also lets us provide conversions from kuid into userspace values. Rust Binder needs these operations because it needs to compare kuids for equality, and it needs to tell userspace about the pid and uid of incoming transactions. To read kuids from a `struct task_struct`, you must currently use various #defines that perform the appropriate field access under an RCU read lock. Currently, we do not have a Rust wrapper for rcu_read_lock, which means that for this patch, there are two ways forward: 1. Inline the methods into Rust code, and use __rcu_read_lock directly rather than the rcu_read_lock wrapper. This gives up lockdep for these usages of RCU. 2. Wrap the various #defines in helpers and call the helpers from Rust. This patch uses the second option. One possible disadvantage of the second option is the possible introduction of speculation gadgets, but as discussed in [1], the risk appears to be acceptable. Of course, once a wrapper for rcu_read_lock is available, it is preferable to use that over either of the two above approaches. Link: https://lore.kernel.org/all/202312080947.674CD2DC7@keescook/ [1] Reviewed-by: Benno Lossin Reviewed-by: Martin Rodriguez Reboredo Reviewed-by: Trevor Gross Signed-off-by: Alice Ryhl Link: https://lore.kernel.org/r/20240915-alice-file-v10-7-88484f7a3dcf@google.com Signed-off-by: Christian Brauner --- rust/helpers/task.c | 38 ++++++++++++++++++++++++++++++++++++++ 1 file changed, 38 insertions(+) (limited to 'rust/helpers/task.c') diff --git a/rust/helpers/task.c b/rust/helpers/task.c index 7ac789232d11c..7d66487db8312 100644 --- a/rust/helpers/task.c +++ b/rust/helpers/task.c @@ -17,3 +17,41 @@ void rust_helper_put_task_struct(struct task_struct *t) { put_task_struct(t); } + +kuid_t rust_helper_task_uid(struct task_struct *task) +{ + return task_uid(task); +} + +kuid_t rust_helper_task_euid(struct task_struct *task) +{ + return task_euid(task); +} + +#ifndef CONFIG_USER_NS +uid_t rust_helper_from_kuid(struct user_namespace *to, kuid_t uid) +{ + return from_kuid(to, uid); +} +#endif /* CONFIG_USER_NS */ + +bool rust_helper_uid_eq(kuid_t left, kuid_t right) +{ + return uid_eq(left, right); +} + +kuid_t rust_helper_current_euid(void) +{ + return current_euid(); +} + +struct user_namespace *rust_helper_current_user_ns(void) +{ + return current_user_ns(); +} + +pid_t rust_helper_task_tgid_nr_ns(struct task_struct *tsk, + struct pid_namespace *ns) +{ + return task_tgid_nr_ns(tsk, ns); +} -- cgit v1.2.3 From d4d7c05f9656fd8e14c6977a54986264eb296ec8 Mon Sep 17 00:00:00 2001 From: Tamir Duberstein Date: Wed, 9 Oct 2024 12:25:30 -0400 Subject: rust: helpers: remove unnecessary header includes Commit e26fa546042a ("rust: kbuild: auto generate helper exports") removed the need for these by automatically generating the exports; it removed the explicit uses of `EXPORT_SYMBOL_GPL` but didn't remove the `#include `s. Signed-off-by: Tamir Duberstein Reviewed-by: Gary Guo Reviewed-by: Andreas Hindborg Link: https://lore.kernel.org/r/20241009162553.27845-2-tamird@gmail.com [ Reworded title. - Miguel ] Signed-off-by: Miguel Ojeda --- rust/helpers/build_bug.c | 1 - rust/helpers/err.c | 1 - rust/helpers/kunit.c | 1 - rust/helpers/mutex.c | 1 - rust/helpers/refcount.c | 1 - rust/helpers/signal.c | 1 - rust/helpers/spinlock.c | 1 - rust/helpers/task.c | 1 - rust/helpers/wait.c | 1 - rust/helpers/workqueue.c | 1 - 10 files changed, 10 deletions(-) (limited to 'rust/helpers/task.c') diff --git a/rust/helpers/build_bug.c b/rust/helpers/build_bug.c index e994f7b5928c0..44e5794880373 100644 --- a/rust/helpers/build_bug.c +++ b/rust/helpers/build_bug.c @@ -1,6 +1,5 @@ // SPDX-License-Identifier: GPL-2.0 -#include #include const char *rust_helper_errname(int err) diff --git a/rust/helpers/err.c b/rust/helpers/err.c index be3d45ef78a25..544c7cb866328 100644 --- a/rust/helpers/err.c +++ b/rust/helpers/err.c @@ -1,7 +1,6 @@ // SPDX-License-Identifier: GPL-2.0 #include -#include __force void *rust_helper_ERR_PTR(long err) { diff --git a/rust/helpers/kunit.c b/rust/helpers/kunit.c index 9d725067eb3bc..b85a4d394c118 100644 --- a/rust/helpers/kunit.c +++ b/rust/helpers/kunit.c @@ -1,7 +1,6 @@ // SPDX-License-Identifier: GPL-2.0 #include -#include struct kunit *rust_helper_kunit_get_current_test(void) { diff --git a/rust/helpers/mutex.c b/rust/helpers/mutex.c index a17ca8cdb50ca..7e00680958ef1 100644 --- a/rust/helpers/mutex.c +++ b/rust/helpers/mutex.c @@ -1,6 +1,5 @@ // SPDX-License-Identifier: GPL-2.0 -#include #include void rust_helper_mutex_lock(struct mutex *lock) diff --git a/rust/helpers/refcount.c b/rust/helpers/refcount.c index f47afc148ec36..d6adbd2e45a18 100644 --- a/rust/helpers/refcount.c +++ b/rust/helpers/refcount.c @@ -1,6 +1,5 @@ // SPDX-License-Identifier: GPL-2.0 -#include #include refcount_t rust_helper_REFCOUNT_INIT(int n) diff --git a/rust/helpers/signal.c b/rust/helpers/signal.c index 63c407f80c26b..1a6bbe9438e28 100644 --- a/rust/helpers/signal.c +++ b/rust/helpers/signal.c @@ -1,6 +1,5 @@ // SPDX-License-Identifier: GPL-2.0 -#include #include int rust_helper_signal_pending(struct task_struct *t) diff --git a/rust/helpers/spinlock.c b/rust/helpers/spinlock.c index 775ed4d549aef..b7b0945e8b3cb 100644 --- a/rust/helpers/spinlock.c +++ b/rust/helpers/spinlock.c @@ -1,6 +1,5 @@ // SPDX-License-Identifier: GPL-2.0 -#include #include void rust_helper___spin_lock_init(spinlock_t *lock, const char *name, diff --git a/rust/helpers/task.c b/rust/helpers/task.c index 7ac789232d11c..190fdb2c8e2f4 100644 --- a/rust/helpers/task.c +++ b/rust/helpers/task.c @@ -1,6 +1,5 @@ // SPDX-License-Identifier: GPL-2.0 -#include #include struct task_struct *rust_helper_get_current(void) diff --git a/rust/helpers/wait.c b/rust/helpers/wait.c index c7336bbf27507..ae48e33d9da3b 100644 --- a/rust/helpers/wait.c +++ b/rust/helpers/wait.c @@ -1,6 +1,5 @@ // SPDX-License-Identifier: GPL-2.0 -#include #include void rust_helper_init_wait(struct wait_queue_entry *wq_entry) diff --git a/rust/helpers/workqueue.c b/rust/helpers/workqueue.c index f59427acc3237..b2b82753509bf 100644 --- a/rust/helpers/workqueue.c +++ b/rust/helpers/workqueue.c @@ -1,6 +1,5 @@ // SPDX-License-Identifier: GPL-2.0 -#include #include void rust_helper_init_work_with_key(struct work_struct *work, work_func_t func, -- cgit v1.2.3