From bbc46b23af5bb934cd1cf066ef4342cee457a24e Mon Sep 17 00:00:00 2001 From: Simon Schuster Date: Mon, 1 Sep 2025 15:09:52 +0200 Subject: arch: copy_thread: pass clone_flags as u64 With the introduction of clone3 in commit 7f192e3cd316 ("fork: add clone3") the effective bit width of clone_flags on all architectures was increased from 32-bit to 64-bit, with a new type of u64 for the flags. However, for most consumers of clone_flags the interface was not changed from the previous type of unsigned long. While this works fine as long as none of the new 64-bit flag bits (CLONE_CLEAR_SIGHAND and CLONE_INTO_CGROUP) are evaluated, this is still undesirable in terms of the principle of least surprise. Thus, this commit fixes all relevant interfaces of the copy_thread function that is called from copy_process to consistently pass clone_flags as u64, so that no truncation to 32-bit integers occurs on 32-bit architectures. Signed-off-by: Simon Schuster Link: https://lore.kernel.org/20250901-nios2-implement-clone3-v2-3-53fcf5577d57@siemens-energy.com Fixes: c5febea0956fd387 ("fork: Pass struct kernel_clone_args into copy_thread") Acked-by: Guo Ren (Alibaba Damo Academy) Acked-by: Andreas Larsson # sparc Acked-by: David Hildenbrand Acked-by: Geert Uytterhoeven # m68k Reviewed-by: Arnd Bergmann Signed-off-by: Christian Brauner --- arch/mips/kernel/process.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) (limited to 'arch/mips/kernel/process.c') diff --git a/arch/mips/kernel/process.c b/arch/mips/kernel/process.c index 02aa6a04a21d..29191fa1801e 100644 --- a/arch/mips/kernel/process.c +++ b/arch/mips/kernel/process.c @@ -107,7 +107,7 @@ int arch_dup_task_struct(struct task_struct *dst, struct task_struct *src) */ int copy_thread(struct task_struct *p, const struct kernel_clone_args *args) { - unsigned long clone_flags = args->flags; + u64 clone_flags = args->flags; unsigned long usp = args->stack; unsigned long tls = args->tls; struct thread_info *ti = task_thread_info(p); -- cgit v1.2.3