The following commit has been merged into the x86/fpu branch of tip:
Commit-ID: 2dd8eedc80b184bb16aad697ae60367c5bf07299
Gitweb: https://git.kernel.org/tip/2dd8eedc80b184bb16aad697ae60367c5bf07299
Author: Thomas Gleixner <tglx@xxxxxxxxxxxxx>
AuthorDate: Wed, 13 Oct 2021 16:55:45 +02:00
Committer: Borislav Petkov <bp@xxxxxxx>
CommitterDate: Thu, 21 Oct 2021 09:33:41 +02:00
x86/process: Move arch_thread_struct_whitelist() out of line
In preparation for dynamically enabled FPU features move the function
out of line as the goal is to expose less and not more information.
Signed-off-by: Thomas Gleixner <tglx@xxxxxxxxxxxxx>
Signed-off-by: Borislav Petkov <bp@xxxxxxx>
Link: https://lkml.kernel.org/r/20211013145322.869001791@xxxxxxxxxxxxx
---
arch/x86/include/asm/processor.h | 9 +++------
arch/x86/kernel/fpu/core.c | 10 ++++++++++
arch/x86/kernel/fpu/internal.h | 2 ++
3 files changed, 15 insertions(+), 6 deletions(-)
diff --git a/arch/x86/include/asm/processor.h b/arch/x86/include/asm/processor.h
index 4519d33..1bd3e8d 100644
--- a/arch/x86/include/asm/processor.h
+++ b/arch/x86/include/asm/processor.h
@@ -461,9 +461,6 @@ DECLARE_PER_CPU(struct irq_stack *, hardirq_stack_ptr);
DECLARE_PER_CPU(struct irq_stack *, softirq_stack_ptr);
#endif /* !X86_64 */
-extern unsigned int fpu_kernel_xstate_size;
-extern unsigned int fpu_user_xstate_size;
-
struct perf_event;
struct thread_struct {
@@ -537,12 +534,12 @@ struct thread_struct {
*/
};
-/* Whitelist the FPU register state from the task_struct for hardened usercopy. */
+extern void fpu_thread_struct_whitelist(unsigned long *offset, unsigned long *size);
+
static inline void arch_thread_struct_whitelist(unsigned long *offset,
unsigned long *size)
{
- *offset = offsetof(struct thread_struct, fpu.__fpstate.regs);
- *size = fpu_kernel_xstate_size;
+ fpu_thread_struct_whitelist(offset, size);
}
static inline void
diff --git a/arch/x86/kernel/fpu/core.c b/arch/x86/kernel/fpu/core.c
index 14560fd..c6df975 100644
--- a/arch/x86/kernel/fpu/core.c
+++ b/arch/x86/kernel/fpu/core.c
@@ -405,6 +405,16 @@ int fpu_clone(struct task_struct *dst)
}
/*
+ * Whitelist the FPU register state embedded into task_struct for hardened
+ * usercopy.
+ */
+void fpu_thread_struct_whitelist(unsigned long *offset, unsigned long *size)
+{
+ *offset = offsetof(struct thread_struct, fpu.__fpstate.regs);
+ *size = fpu_kernel_xstate_size;
+}
+
+/*
* Drops current FPU state: deactivates the fpregs and
* the fpstate. NOTE: it still leaves previous contents
* in the fpregs in the eager-FPU case.
diff --git a/arch/x86/kernel/fpu/internal.h b/arch/x86/kernel/fpu/internal.h
index e1d8a35..5c4f71f 100644
--- a/arch/x86/kernel/fpu/internal.h
+++ b/arch/x86/kernel/fpu/internal.h
@@ -2,6 +2,8 @@
#ifndef __X86_KERNEL_FPU_INTERNAL_H
#define __X86_KERNEL_FPU_INTERNAL_H
+extern unsigned int fpu_kernel_xstate_size;
+extern unsigned int fpu_user_xstate_size;
extern struct fpstate init_fpstate;
/* CPU feature check wrappers */
|