Merge branch 'syscalls-next' of git://git.kernel.org/pub/scm/linux/kernel/git/brodo/linux

Pull removal of in-kernel calls to syscalls from Dominik Brodowski:
 "System calls are interaction points between userspace and the kernel.
  Therefore, system call functions such as sys_xyzzy() or
  compat_sys_xyzzy() should only be called from userspace via the
  syscall table, but not from elsewhere in the kernel.

  At least on 64-bit x86, it will likely be a hard requirement from
  v4.17 onwards to not call system call functions in the kernel: It is
  better to use use a different calling convention for system calls
  there, where struct pt_regs is decoded on-the-fly in a syscall wrapper
  which then hands processing over to the actual syscall function. This
  means that only those parameters which are actually needed for a
  specific syscall are passed on during syscall entry, instead of
  filling in six CPU registers with random user space content all the
  time (which may cause serious trouble down the call chain). Those
  x86-specific patches will be pushed through the x86 tree in the near
  future.

  Moreover, rules on how data may be accessed may differ between kernel
  data and user data. This is another reason why calling sys_xyzzy() is
  generally a bad idea, and -- at most -- acceptable in arch-specific
  code.

  This patchset removes all in-kernel calls to syscall functions in the
  kernel with the exception of arch/. On top of this, it cleans up the
  three places where many syscalls are referenced or prototyped, namely
  kernel/sys_ni.c, include/linux/syscalls.h and include/linux/compat.h"

* 'syscalls-next' of git://git.kernel.org/pub/scm/linux/kernel/git/brodo/linux: (109 commits)
  bpf: whitelist all syscalls for error injection
  kernel/sys_ni: remove {sys_,sys_compat} from cond_syscall definitions
  kernel/sys_ni: sort cond_syscall() entries
  syscalls/x86: auto-create compat_sys_*() prototypes
  syscalls: sort syscall prototypes in include/linux/compat.h
  net: remove compat_sys_*() prototypes from net/compat.h
  syscalls: sort syscall prototypes in include/linux/syscalls.h
  kexec: move sys_kexec_load() prototype to syscalls.h
  x86/sigreturn: use SYSCALL_DEFINE0
  x86: fix sys_sigreturn() return type to be long, not unsigned long
  x86/ioport: add ksys_ioperm() helper; remove in-kernel calls to sys_ioperm()
  mm: add ksys_readahead() helper; remove in-kernel calls to sys_readahead()
  mm: add ksys_mmap_pgoff() helper; remove in-kernel calls to sys_mmap_pgoff()
  mm: add ksys_fadvise64_64() helper; remove in-kernel call to sys_fadvise64_64()
  fs: add ksys_fallocate() wrapper; remove in-kernel calls to sys_fallocate()
  fs: add ksys_p{read,write}64() helpers; remove in-kernel calls to syscalls
  fs: add ksys_truncate() wrapper; remove in-kernel calls to sys_truncate()
  fs: add ksys_sync_file_range helper(); remove in-kernel calls to syscall
  kernel: add ksys_setsid() helper; remove in-kernel call to sys_setsid()
  kernel: add ksys_unshare() helper; remove in-kernel calls to sys_unshare()
  ...

1 files changed, 13 insertions, 12 deletions

diff --git a/kernel/uid16.c b/kernel/uid16.c
index ef1da2a5f9bd..af6925d8599b 100644
--- a/kernel/uid16.c
+++ b/kernel/uid16.c
@@ -18,44 +18,46 @@
 
 #include <linux/uaccess.h>
 
+#include "uid16.h"
+
 SYSCALL_DEFINE3(chown16, const char __user *, filename, old_uid_t, user, old_gid_t, group)
 {
-	return sys_chown(filename, low2highuid(user), low2highgid(group));
+	return ksys_chown(filename, low2highuid(user), low2highgid(group));
 }
 
 SYSCALL_DEFINE3(lchown16, const char __user *, filename, old_uid_t, user, old_gid_t, group)
 {
-	return sys_lchown(filename, low2highuid(user), low2highgid(group));
+	return ksys_lchown(filename, low2highuid(user), low2highgid(group));
 }
 
 SYSCALL_DEFINE3(fchown16, unsigned int, fd, old_uid_t, user, old_gid_t, group)
 {
-	return sys_fchown(fd, low2highuid(user), low2highgid(group));
+	return ksys_fchown(fd, low2highuid(user), low2highgid(group));
 }
 
 SYSCALL_DEFINE2(setregid16, old_gid_t, rgid, old_gid_t, egid)
 {
-	return sys_setregid(low2highgid(rgid), low2highgid(egid));
+	return __sys_setregid(low2highgid(rgid), low2highgid(egid));
 }
 
 SYSCALL_DEFINE1(setgid16, old_gid_t, gid)
 {
-	return sys_setgid(low2highgid(gid));
+	return __sys_setgid(low2highgid(gid));
 }
 
 SYSCALL_DEFINE2(setreuid16, old_uid_t, ruid, old_uid_t, euid)
 {
-	return sys_setreuid(low2highuid(ruid), low2highuid(euid));
+	return __sys_setreuid(low2highuid(ruid), low2highuid(euid));
 }
 
 SYSCALL_DEFINE1(setuid16, old_uid_t, uid)
 {
-	return sys_setuid(low2highuid(uid));
+	return __sys_setuid(low2highuid(uid));
 }
 
 SYSCALL_DEFINE3(setresuid16, old_uid_t, ruid, old_uid_t, euid, old_uid_t, suid)
 {
-	return sys_setresuid(low2highuid(ruid), low2highuid(euid),
+	return __sys_setresuid(low2highuid(ruid), low2highuid(euid),
 				 low2highuid(suid));
 }
 
@@ -78,11 +80,10 @@ SYSCALL_DEFINE3(getresuid16, old_uid_t __user *, ruidp, old_uid_t __user *, euid
 
 SYSCALL_DEFINE3(setresgid16, old_gid_t, rgid, old_gid_t, egid, old_gid_t, sgid)
 {
-	return sys_setresgid(low2highgid(rgid), low2highgid(egid),
+	return __sys_setresgid(low2highgid(rgid), low2highgid(egid),
 				 low2highgid(sgid));
 }
 
-
 SYSCALL_DEFINE3(getresgid16, old_gid_t __user *, rgidp, old_gid_t __user *, egidp, old_gid_t __user *, sgidp)
 {
 	const struct cred *cred = current_cred();
@@ -102,12 +103,12 @@ SYSCALL_DEFINE3(getresgid16, old_gid_t __user *, rgidp, old_gid_t __user *, egid
 
 SYSCALL_DEFINE1(setfsuid16, old_uid_t, uid)
 {
-	return sys_setfsuid(low2highuid(uid));
+	return __sys_setfsuid(low2highuid(uid));
 }
 
 SYSCALL_DEFINE1(setfsgid16, old_gid_t, gid)
 {
-	return sys_setfsgid(low2highgid(gid));
+	return __sys_setfsgid(low2highgid(gid));
 }
 
 static int groups16_to_user(old_gid_t __user *grouplist,