[PATCH v10 2/7] x86/arch_prctl/64: Rename do_arch_prctl to do_arch_prctl_64
From: Kyle Huey
Date: Tue Nov 08 2016 - 13:42:01 EST
In order to introduce new arch_prctls that are not 64 bit only, rename the
existing 64 bit implementation to do_arch_prctl_64. Also rename the second
argument to arch_prctl, which will no longer always be an address.
Signed-off-by: Kyle Huey <khuey@xxxxxxxxxxxx>
Reviewed-by: Andy Lutomirski <luto@xxxxxxxxxx>
---
arch/x86/include/asm/proto.h | 4 +++-
arch/x86/kernel/process_64.c | 32 +++++++++++++++++---------------
arch/x86/kernel/ptrace.c | 8 ++++----
arch/x86/um/syscalls_64.c | 4 ++--
4 files changed, 26 insertions(+), 22 deletions(-)
diff --git a/arch/x86/include/asm/proto.h b/arch/x86/include/asm/proto.h
index 9b9b30b..95c3e51 100644
--- a/arch/x86/include/asm/proto.h
+++ b/arch/x86/include/asm/proto.h
@@ -25,11 +25,13 @@ void entry_SYSCALL_compat(void);
void entry_INT80_compat(void);
#endif
void x86_configure_nx(void);
void x86_report_nx(void);
extern int reboot_force;
-long do_arch_prctl(struct task_struct *task, int code, unsigned long addr);
+#ifdef CONFIG_X86_64
+long do_arch_prctl_64(struct task_struct *task, int code, unsigned long arg2);
+#endif
#endif /* _ASM_X86_PROTO_H */
diff --git a/arch/x86/kernel/process_64.c b/arch/x86/kernel/process_64.c
index 2718cf9..611df20 100644
--- a/arch/x86/kernel/process_64.c
+++ b/arch/x86/kernel/process_64.c
@@ -193,17 +193,17 @@ int copy_thread_tls(unsigned long clone_flags, unsigned long sp,
*/
if (clone_flags & CLONE_SETTLS) {
#ifdef CONFIG_IA32_EMULATION
if (in_ia32_syscall())
err = do_set_thread_area(p, -1,
(struct user_desc __user *)tls, 0);
else
#endif
- err = do_arch_prctl(p, ARCH_SET_FS, tls);
+ err = do_arch_prctl_64(p, ARCH_SET_FS, tls);
if (err)
goto out;
}
err = 0;
out:
if (err && p->thread.io_bitmap_ptr) {
kfree(p->thread.io_bitmap_ptr);
p->thread.io_bitmap_max = 0;
@@ -534,91 +534,93 @@ static long prctl_map_vdso(const struct vdso_image *image, unsigned long addr)
ret = map_vdso_once(image, addr);
if (ret)
return ret;
return (long)image->size;
}
#endif
-long do_arch_prctl(struct task_struct *task, int code, unsigned long addr)
+long do_arch_prctl_64(struct task_struct *task, int code, unsigned long arg2)
{
int ret = 0;
int doit = task == current;
int cpu;
switch (code) {
case ARCH_SET_GS:
- if (addr >= TASK_SIZE_MAX)
+ if (arg2 >= TASK_SIZE_MAX)
return -EPERM;
cpu = get_cpu();
task->thread.gsindex = 0;
- task->thread.gsbase = addr;
+ task->thread.gsbase = arg2;
if (doit) {
load_gs_index(0);
- ret = wrmsrl_safe(MSR_KERNEL_GS_BASE, addr);
+ ret = wrmsrl_safe(MSR_KERNEL_GS_BASE, arg2);
}
put_cpu();
break;
case ARCH_SET_FS:
/* Not strictly needed for fs, but do it for symmetry
with gs */
- if (addr >= TASK_SIZE_MAX)
+ if (arg2 >= TASK_SIZE_MAX)
return -EPERM;
cpu = get_cpu();
task->thread.fsindex = 0;
- task->thread.fsbase = addr;
+ task->thread.fsbase = arg2;
if (doit) {
/* set the selector to 0 to not confuse __switch_to */
loadsegment(fs, 0);
- ret = wrmsrl_safe(MSR_FS_BASE, addr);
+ ret = wrmsrl_safe(MSR_FS_BASE, arg2);
}
put_cpu();
break;
case ARCH_GET_FS: {
unsigned long base;
+
if (doit)
rdmsrl(MSR_FS_BASE, base);
else
base = task->thread.fsbase;
- ret = put_user(base, (unsigned long __user *)addr);
+ ret = put_user(base, (unsigned long __user *)arg2);
break;
}
case ARCH_GET_GS: {
unsigned long base;
+
if (doit)
rdmsrl(MSR_KERNEL_GS_BASE, base);
else
base = task->thread.gsbase;
- ret = put_user(base, (unsigned long __user *)addr);
+ ret = put_user(base, (unsigned long __user *)arg2);
break;
}
#ifdef CONFIG_CHECKPOINT_RESTORE
# ifdef CONFIG_X86_X32_ABI
case ARCH_MAP_VDSO_X32:
- return prctl_map_vdso(&vdso_image_x32, addr);
+ return prctl_map_vdso(&vdso_image_x32, arg2);
# endif
# if defined CONFIG_X86_32 || defined CONFIG_IA32_EMULATION
case ARCH_MAP_VDSO_32:
- return prctl_map_vdso(&vdso_image_32, addr);
+ return prctl_map_vdso(&vdso_image_32, arg2);
# endif
case ARCH_MAP_VDSO_64:
- return prctl_map_vdso(&vdso_image_64, addr);
+ return prctl_map_vdso(&vdso_image_64, arg2);
#endif
default:
ret = -EINVAL;
break;
}
return ret;
}
-SYSCALL_DEFINE2(arch_prctl, int, code, unsigned long, addr)
+SYSCALL_DEFINE2(arch_prctl, int, code, unsigned long, arg2)
{
- return do_arch_prctl(current, code, addr);
+ return do_arch_prctl_64(current, code, arg2);
}
unsigned long KSTK_ESP(struct task_struct *task)
{
return task_pt_regs(task)->sp;
}
diff --git a/arch/x86/kernel/ptrace.c b/arch/x86/kernel/ptrace.c
index 0e63c02..5004302 100644
--- a/arch/x86/kernel/ptrace.c
+++ b/arch/x86/kernel/ptrace.c
@@ -390,31 +390,31 @@ static int putreg(struct task_struct *child,
case offsetof(struct user_regs_struct, flags):
return set_flags(child, value);
#ifdef CONFIG_X86_64
case offsetof(struct user_regs_struct,fs_base):
if (value >= TASK_SIZE_MAX)
return -EIO;
/*
- * When changing the segment base, use do_arch_prctl
+ * When changing the segment base, use do_arch_prctl_64
* to set either thread.fs or thread.fsindex and the
* corresponding GDT slot.
*/
if (child->thread.fsbase != value)
- return do_arch_prctl(child, ARCH_SET_FS, value);
+ return do_arch_prctl_64(child, ARCH_SET_FS, value);
return 0;
case offsetof(struct user_regs_struct,gs_base):
/*
* Exactly the same here as the %fs handling above.
*/
if (value >= TASK_SIZE_MAX)
return -EIO;
if (child->thread.gsbase != value)
- return do_arch_prctl(child, ARCH_SET_GS, value);
+ return do_arch_prctl_64(child, ARCH_SET_GS, value);
return 0;
#endif
}
*pt_regs_access(task_pt_regs(child), offset) = value;
return 0;
}
@@ -863,17 +863,17 @@ long arch_ptrace(struct task_struct *child, long request,
break;
#endif
#ifdef CONFIG_X86_64
/* normal 64bit interface to access TLS data.
Works just like arch_prctl, except that the arguments
are reversed. */
case PTRACE_ARCH_PRCTL:
- ret = do_arch_prctl(child, data, addr);
+ ret = do_arch_prctl_64(child, data, addr);
break;
#endif
default:
ret = ptrace_request(child, request, addr, data);
break;
}
diff --git a/arch/x86/um/syscalls_64.c b/arch/x86/um/syscalls_64.c
index ab3f7f4..3362c4e 100644
--- a/arch/x86/um/syscalls_64.c
+++ b/arch/x86/um/syscalls_64.c
@@ -68,19 +68,19 @@ long arch_prctl(struct task_struct *task, int code, unsigned long __user *addr)
case ARCH_GET_GS:
ret = put_user(tmp, addr);
break;
}
return ret;
}
-SYSCALL_DEFINE2(arch_prctl, int, code, unsigned long, addr)
+SYSCALL_DEFINE2(arch_prctl, int, code, unsigned long, arg2)
{
- return arch_prctl(current, code, (unsigned long __user *) addr);
+ return arch_prctl(current, code, (unsigned long __user *) arg2);
}
void arch_switch_to(struct task_struct *to)
{
if ((to->thread.arch.fs == 0) || (to->mm == NULL))
return;
arch_prctl(to, ARCH_SET_FS, (void __user *) to->thread.arch.fs);
--
2.10.2