avr32: sanitize copy_thread(), switch to generic fork/vfork/clone, kill wrappers

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>

4 files changed, 11 insertions, 47 deletions

diff --git a/arch/avr32/include/asm/unistd.h b/arch/avr32/include/asm/unistd.h
index 641023d1bcb5..f05a9804e8e2 100644
--- a/arch/avr32/include/asm/unistd.h
+++ b/arch/avr32/include/asm/unistd.h
@@ -40,6 +40,9 @@
 #define __ARCH_WANT_SYS_RT_SIGACTION
 #define __ARCH_WANT_SYS_RT_SIGSUSPEND
 #define __ARCH_WANT_SYS_EXECVE
+#define __ARCH_WANT_SYS_FORK
+#define __ARCH_WANT_SYS_VFORK
+#define __ARCH_WANT_SYS_CLONE
 
 /*
  * "Conditional" syscalls
diff --git a/arch/avr32/kernel/process.c b/arch/avr32/kernel/process.c
index 09b894d96d6e..03d7aa4a4bc9 100644
--- a/arch/avr32/kernel/process.c
+++ b/arch/avr32/kernel/process.c
@@ -299,11 +299,11 @@ asmlinkage void syscall_return(void);
 
 int copy_thread(unsigned long clone_flags, unsigned long usp,
                 unsigned long arg,
-                struct task_struct *p, struct pt_regs *regs)
+                struct task_struct *p, struct pt_regs *unused)
 {
         struct pt_regs *childregs = task_pt_regs(p);
 
-        if (unlikely(!regs)) {
+        if (unlikely(p->flags & PF_KTHREAD)) {
                 memset(childregs, 0, sizeof(struct pt_regs));
                 p->thread.cpu_context.r0 = arg;
                 p->thread.cpu_context.r1 = usp; /* fn */
@@ -311,8 +311,9 @@ int copy_thread(unsigned long clone_flags, unsigned long usp,
                 p->thread.cpu_context.pc = (unsigned long)ret_from_kernel_thread;
                 childregs->sr = MODE_SUPERVISOR;
         } else {
-                *childregs = *regs;
-                childregs->sp = usp;
+                *childregs = *current_pt_regs();
+                if (usp)
+                        childregs->sp = usp;
                 childregs->r12 = 0; /* Set return value for child */
                 p->thread.cpu_context.pc = (unsigned long)ret_from_fork;
         }
@@ -327,28 +328,6 @@ int copy_thread(unsigned long clone_flags, unsigned long usp,
         return 0;
 }
 
-/* r12-r8 are dummy parameters to force the compiler to use the stack */
-asmlinkage int sys_fork(struct pt_regs *regs)
-{
-        return do_fork(SIGCHLD, regs->sp, regs, 0, NULL, NULL);
-}
-
-asmlinkage int sys_clone(unsigned long clone_flags, unsigned long newsp,
-                void __user *parent_tidptr, void __user *child_tidptr,
-                struct pt_regs *regs)
-{
-        if (!newsp)
-                newsp = regs->sp;
-        return do_fork(clone_flags, newsp, regs, 0, parent_tidptr,
-                        child_tidptr);
-}
-
-asmlinkage int sys_vfork(struct pt_regs *regs)
-{
-        return do_fork(CLONE_VFORK | CLONE_VM | SIGCHLD, regs->sp, regs,
-                       0, NULL, NULL);
-}
-
 /*
  * This function is supposed to answer the question "who called
  * schedule()?"
diff --git a/arch/avr32/kernel/syscall-stubs.S b/arch/avr32/kernel/syscall-stubs.S
index 285a61b9194e..275aab9731fd 100644
--- a/arch/avr32/kernel/syscall-stubs.S
+++ b/arch/avr32/kernel/syscall-stubs.S
@@ -32,24 +32,6 @@ __sys_rt_sigreturn:
         mov     r12, sp
         rjmp    sys_rt_sigreturn
 
-        .global __sys_fork
-        .type   __sys_fork,@function
-__sys_fork:
-        mov     r12, sp
-        rjmp    sys_fork
-
-        .global __sys_clone
-        .type   __sys_clone,@function
-__sys_clone:
-        mov     r8, sp
-        rjmp    sys_clone
-
-        .global __sys_vfork
-        .type   __sys_vfork,@function
-__sys_vfork:
-        mov     r12, sp
-        rjmp    sys_vfork
-
         .global __sys_mmap2
         .type   __sys_mmap2,@function
 __sys_mmap2:
diff --git a/arch/avr32/kernel/syscall_table.S b/arch/avr32/kernel/syscall_table.S
index fc6497706819..f27bb878da6b 100644
--- a/arch/avr32/kernel/syscall_table.S
+++ b/arch/avr32/kernel/syscall_table.S
@@ -15,7 +15,7 @@
 sys_call_table:
         .long   sys_restart_syscall
         .long   sys_exit
-        .long   __sys_fork
+        .long   sys_fork
         .long   sys_read
         .long   sys_write
         .long   sys_open                /* 5 */
@@ -57,7 +57,7 @@ sys_call_table:
         .long   sys_dup
         .long   sys_pipe
         .long   sys_times
-        .long   __sys_clone
+        .long   sys_clone
         .long   sys_brk                 /* 45 */
         .long   sys_setgid
         .long   sys_getgid
@@ -127,7 +127,7 @@ sys_call_table:
         .long   sys_newuname
         .long   sys_adjtimex
         .long   sys_mprotect
-        .long   __sys_vfork
+        .long   sys_vfork
         .long   sys_init_module         /* 115 */
         .long   sys_delete_module
         .long   sys_quotactl