x86, um/x86: switch to generic sys_execve and kernel_execve

32bit wrapper is lost on that; 64bit one is *not*, since
we need to arrange for full pt_regs on stack when we call
sys_execve() and we need to load callee-saved ones from
there afterwards.

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

3 files changed, 2 insertions, 41 deletions

diff --git a/arch/um/kernel/exec.c b/arch/um/kernel/exec.c
index 8c82786da823..e427301f55d6 100644
--- a/arch/um/kernel/exec.c
+++ b/arch/um/kernel/exec.c
@@ -16,7 +16,6 @@
 #include "mem_user.h"
 #include "skas.h"
 #include "os.h"
-#include "internal.h"
 
 void flush_thread(void)
 {
@@ -49,27 +48,7 @@ void start_thread(struct pt_regs *regs, unsigned long eip, unsigned long esp)
 }
 EXPORT_SYMBOL(start_thread);
 
-long um_execve(const char *file, const char __user *const __user *argv, const char __user *const __user *env)
+void __noreturn ret_from_kernel_execve(struct pt_regs *unused)
 {
-        long err;
-
-        err = do_execve(file, argv, env, &current->thread.regs);
-        if (!err)
-                UML_LONGJMP(current->thread.exec_buf, 1);
-        return err;
-}
-
-long sys_execve(const char __user *file, const char __user *const __user *argv,
-                const char __user *const __user *env)
-{
-        long error;
-        char *filename;
-
-        filename = getname(file);
-        error = PTR_ERR(filename);
-        if (IS_ERR(filename)) goto out;
-        error = do_execve(filename, argv, env, &current->thread.regs);
-        putname(filename);
- out:
-        return error;
+        UML_LONGJMP(current->thread.exec_buf, 1);
 }
diff --git a/arch/um/kernel/internal.h b/arch/um/kernel/internal.h
deleted file mode 100644
index 5bf97db24a04..000000000000
--- a/arch/um/kernel/internal.h
+++ /dev/null
@@ -1 +0,0 @@
-extern long um_execve(const char *file, const char __user *const __user *argv, const char __user *const __user *env);
diff --git a/arch/um/kernel/syscall.c b/arch/um/kernel/syscall.c
index a4c6d8eee74c..a5639c472772 100644
--- a/arch/um/kernel/syscall.c
+++ b/arch/um/kernel/syscall.c
@@ -13,7 +13,6 @@
 #include "asm/mman.h"
 #include "asm/uaccess.h"
 #include "asm/unistd.h"
-#include "internal.h"
 
 long sys_fork(void)
 {
@@ -50,19 +49,3 @@ long old_mmap(unsigned long addr, unsigned long len,
  out:
         return err;
 }
-
-int kernel_execve(const char *filename,
-                  const char *const argv[],
-                  const char *const envp[])
-{
-        mm_segment_t fs;
-        int ret;
-
-        fs = get_fs();
-        set_fs(KERNEL_DS);
-        ret = um_execve(filename, (const char __user *const __user *)argv,
-                        (const char __user *const __user *) envp);
-        set_fs(fs);
-
-        return ret;
-}