From 876346536c1b59a5b1b5e44477b1b3ece77647fd Mon Sep 17 00:00:00 2001 From: Andreas Hindborg Date: Thu, 15 Aug 2024 10:30:26 +0000 Subject: rust: kbuild: split up helpers.c This patch splits up the rust helpers C file. When rebasing patch sets on upstream linux, merge conflicts in helpers.c is common and time consuming [1]. Thus, split the file so that each kernel component can live in a separate file. This patch lists helper files explicitly and thus conflicts in the file list is still likely. However, they should be more simple to resolve than the conflicts usually seen in helpers.c. [ Removed `README.md` and undeleted the original comment since now, in v3 of the series, we have a `helpers.c` again; which also allows us to keep the "Sorted alphabetically" line and makes the diff easier. In addition, updated the Documentation/ mentions of the file, reworded title and removed blank lines at the end of `page.c`. - Miguel ] Link: https://rust-for-linux.zulipchat.com/#narrow/stream/288089-General/topic/Splitting.20up.20helpers.2Ec/near/426694012 [1] Signed-off-by: Andreas Hindborg Reviewed-by: Gary Guo Acked-by: Dirk Behme Reviewed-by: Alice Ryhl Reviewed-by: Benno Lossin Link: https://lore.kernel.org/r/20240815103016.2771842-1-nmi@metaspace.dk Signed-off-by: Miguel Ojeda --- rust/helpers/task.c | 22 ++++++++++++++++++++++ 1 file changed, 22 insertions(+) create mode 100644 rust/helpers/task.c (limited to 'rust/helpers/task.c') diff --git a/rust/helpers/task.c b/rust/helpers/task.c new file mode 100644 index 000000000000..b176c347f0d4 --- /dev/null +++ b/rust/helpers/task.c @@ -0,0 +1,22 @@ +// SPDX-License-Identifier: GPL-2.0 + +#include +#include + +struct task_struct *rust_helper_get_current(void) +{ + return current; +} +EXPORT_SYMBOL_GPL(rust_helper_get_current); + +void rust_helper_get_task_struct(struct task_struct *t) +{ + get_task_struct(t); +} +EXPORT_SYMBOL_GPL(rust_helper_get_task_struct); + +void rust_helper_put_task_struct(struct task_struct *t) +{ + put_task_struct(t); +} +EXPORT_SYMBOL_GPL(rust_helper_put_task_struct); -- cgit From e26fa546042add70944d018b930530d16b3cf626 Mon Sep 17 00:00:00 2001 From: Gary Guo Date: Sat, 17 Aug 2024 17:51:32 +0100 Subject: rust: kbuild: auto generate helper exports This removes the need to explicitly export all symbols. Generate helper exports similarly to what's currently done for Rust crates. These helpers are exclusively called from within Rust code and therefore can be treated similar as other Rust symbols. Signed-off-by: Gary Guo Reviewed-by: Boqun Feng Tested-by: Boqun Feng Link: https://lore.kernel.org/r/20240817165302.3852499-1-gary@garyguo.net [ Fixed dependency path, reworded slightly, edited comment a bit and rebased on top of the changes made when applying Andreas' patch (e.g. no `README.md` anymore, so moved the edits). - Miguel ] Signed-off-by: Miguel Ojeda --- rust/helpers/task.c | 3 --- 1 file changed, 3 deletions(-) (limited to 'rust/helpers/task.c') diff --git a/rust/helpers/task.c b/rust/helpers/task.c index b176c347f0d4..7ac789232d11 100644 --- a/rust/helpers/task.c +++ b/rust/helpers/task.c @@ -7,16 +7,13 @@ struct task_struct *rust_helper_get_current(void) { return current; } -EXPORT_SYMBOL_GPL(rust_helper_get_current); void rust_helper_get_task_struct(struct task_struct *t) { get_task_struct(t); } -EXPORT_SYMBOL_GPL(rust_helper_get_task_struct); void rust_helper_put_task_struct(struct task_struct *t) { put_task_struct(t); } -EXPORT_SYMBOL_GPL(rust_helper_put_task_struct); -- cgit 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 7ac789232d11..7d66487db831 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 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/task.c | 1 - 1 file changed, 1 deletion(-) (limited to 'rust/helpers/task.c') diff --git a/rust/helpers/task.c b/rust/helpers/task.c index 7ac789232d11..190fdb2c8e2f 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) -- cgit