improve sys_newuname() for compat architectures

On an architecture that supports 32-bit compat we need to override the
reported machine in uname with the 32-bit value.  Instead of doing this
separately in every architecture introduce a COMPAT_UTS_MACHINE define in
<asm/compat.h> and apply it directly in sys_newuname().

Signed-off-by: Christoph Hellwig <hch@lst.de>
Cc: Ralf Baechle <ralf@linux-mips.org>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Paul Mundt <lethal@linux-sh.org>
Cc: Jeff Dike <jdike@addtoit.com>
Cc: Hirokazu Takata <takata@linux-m32r.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: "Luck, Tony" <tony.luck@intel.com>
Cc: James Morris <jmorris@namei.org>
Cc: Andreas Schwab <schwab@linux-m68k.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

27 files changed, 23 insertions, 123 deletions

diff --git a/arch/ia64/include/asm/compat.h b/arch/ia64/include/asm/compat.h
index dfcf75b8426d..f90edc85b509 100644
--- a/arch/ia64/include/asm/compat.h
+++ b/arch/ia64/include/asm/compat.h
@@ -5,7 +5,8 @@
  */
 #include <linux/types.h>
 
-#define COMPAT_USER_HZ  100
+#define COMPAT_USER_HZ          100
+#define COMPAT_UTS_MACHINE      "i686\0\0\0"
 
 typedef u32             compat_size_t;
 typedef s32             compat_ssize_t;
diff --git a/arch/mips/include/asm/compat.h b/arch/mips/include/asm/compat.h
index f58aed354bfd..613f6912dfc1 100644
--- a/arch/mips/include/asm/compat.h
+++ b/arch/mips/include/asm/compat.h
@@ -8,7 +8,8 @@
 #include <asm/page.h>
 #include <asm/ptrace.h>
 
-#define COMPAT_USER_HZ  100
+#define COMPAT_USER_HZ          100
+#define COMPAT_UTS_MACHINE      "mips\0\0\0"
 
 typedef u32             compat_size_t;
 typedef s32             compat_ssize_t;
diff --git a/arch/mips/kernel/linux32.c b/arch/mips/kernel/linux32.c
index bde79ef602e6..a39d0597a375 100644
--- a/arch/mips/kernel/linux32.c
+++ b/arch/mips/kernel/linux32.c
@@ -249,22 +249,6 @@ SYSCALL_DEFINE5(n32_msgrcv, int, msqid, u32, msgp, size_t, msgsz,
 }
 #endif
 
-SYSCALL_DEFINE1(32_newuname, struct new_utsname __user *, name)
-{
-        int ret = 0;
-
-        down_read(&uts_sem);
-        if (copy_to_user(name, utsname(), sizeof *name))
-                ret = -EFAULT;
-        up_read(&uts_sem);
-
-        if (current->personality == PER_LINUX32 && !ret)
-                if (copy_to_user(name->machine, "mips\0\0\0", 8))
-                        ret = -EFAULT;
-
-        return ret;
-}
-
 SYSCALL_DEFINE1(32_personality, unsigned long, personality)
 {
         int ret;
diff --git a/arch/mips/kernel/scall64-n32.S b/arch/mips/kernel/scall64-n32.S
index 66b5a48676dd..44337ba03717 100644
--- a/arch/mips/kernel/scall64-n32.S
+++ b/arch/mips/kernel/scall64-n32.S
@@ -181,7 +181,7 @@ EXPORT(sysn32_call_table)
         PTR     sys_exit
         PTR     compat_sys_wait4
         PTR     sys_kill                        /* 6060 */
-        PTR     sys_32_newuname
+        PTR     sys_newuname
         PTR     sys_semget
         PTR     sys_semop
         PTR     sys_n32_semctl
diff --git a/arch/mips/kernel/scall64-o32.S b/arch/mips/kernel/scall64-o32.S
index 515f9eab2b28..813689ef2384 100644
--- a/arch/mips/kernel/scall64-o32.S
+++ b/arch/mips/kernel/scall64-o32.S
@@ -325,7 +325,7 @@ sys_call_table:
         PTR     sys32_sigreturn
         PTR     sys32_clone                     /* 4120 */
         PTR     sys_setdomainname
-        PTR     sys_32_newuname
+        PTR     sys_newuname
         PTR     sys_ni_syscall                  /* sys_modify_ldt */
         PTR     compat_sys_adjtimex
         PTR     sys_mprotect                    /* 4125 */
diff --git a/arch/parisc/include/asm/compat.h b/arch/parisc/include/asm/compat.h
index 7f32611a7a5e..02b77baa5da6 100644
--- a/arch/parisc/include/asm/compat.h
+++ b/arch/parisc/include/asm/compat.h
@@ -7,7 +7,8 @@
 #include <linux/sched.h>
 #include <linux/thread_info.h>
 
-#define COMPAT_USER_HZ 100
+#define COMPAT_USER_HZ          100
+#define COMPAT_UTS_MACHINE      "parisc\0\0"
 
 typedef u32     compat_size_t;
 typedef s32     compat_ssize_t;
diff --git a/arch/parisc/kernel/sys_parisc.c b/arch/parisc/kernel/sys_parisc.c
index 9147391afb03..c9b932260f47 100644
--- a/arch/parisc/kernel/sys_parisc.c
+++ b/arch/parisc/kernel/sys_parisc.c
@@ -234,18 +234,3 @@ long parisc_personality(unsigned long personality)
 
         return err;
 }
-
-long parisc_newuname(struct new_utsname __user *name)
-{
-        int err = sys_newuname(name);
-
-#ifdef CONFIG_COMPAT
-        if (!err && personality(current->personality) == PER_LINUX32) {
-                if (__put_user(0, name->machine + 6) ||
-                    __put_user(0, name->machine + 7))
-                        err = -EFAULT;
-        }
-#endif
-
-        return err;
-}
diff --git a/arch/parisc/kernel/syscall_table.S b/arch/parisc/kernel/syscall_table.S
index de5f6dab48b7..3d52c978738f 100644
--- a/arch/parisc/kernel/syscall_table.S
+++ b/arch/parisc/kernel/syscall_table.S
@@ -127,7 +127,7 @@
         ENTRY_SAME(socketpair)
         ENTRY_SAME(setpgid)
         ENTRY_SAME(send)
-        ENTRY_OURS(newuname)
+        ENTRY_SAME(newuname)
         ENTRY_SAME(umask)               /* 60 */
         ENTRY_SAME(chroot)
         ENTRY_COMP(ustat)
diff --git a/arch/powerpc/include/asm/compat.h b/arch/powerpc/include/asm/compat.h
index 4774c2f92232..396d21a80058 100644
--- a/arch/powerpc/include/asm/compat.h
+++ b/arch/powerpc/include/asm/compat.h
@@ -7,7 +7,8 @@
 #include <linux/types.h>
 #include <linux/sched.h>
 
-#define COMPAT_USER_HZ  100
+#define COMPAT_USER_HZ          100
+#define COMPAT_UTS_MACHINE      "ppc\0\0"
 
 typedef u32             compat_size_t;
 typedef s32             compat_ssize_t;
diff --git a/arch/powerpc/include/asm/syscalls.h b/arch/powerpc/include/asm/syscalls.h
index 23bb74e7f946..4084e567d28e 100644
--- a/arch/powerpc/include/asm/syscalls.h
+++ b/arch/powerpc/include/asm/syscalls.h
@@ -7,7 +7,6 @@
 #include <linux/types.h>
 #include <asm/signal.h>
 
-struct new_utsname;
 struct pt_regs;
 struct rtas_args;
 struct sigaction;
@@ -38,7 +37,6 @@ asmlinkage long sys_rt_sigaction(int sig,
 asmlinkage long ppc64_personality(unsigned long personality);
 asmlinkage int ppc_rtas(struct rtas_args __user *uargs);
 asmlinkage time_t sys64_time(time_t __user * tloc);
-asmlinkage long ppc_newuname(struct new_utsname __user * name);
 
 asmlinkage long sys_rt_sigsuspend(sigset_t __user *unewset,
                 size_t sigsetsize);
diff --git a/arch/powerpc/include/asm/systbl.h b/arch/powerpc/include/asm/systbl.h
index 07d2d19ab5e9..a5ee345b6a5c 100644
--- a/arch/powerpc/include/asm/systbl.h
+++ b/arch/powerpc/include/asm/systbl.h
@@ -125,7 +125,7 @@ SYSCALL_SPU(fsync)
 SYS32ONLY(sigreturn)
 PPC_SYS(clone)
 COMPAT_SYS_SPU(setdomainname)
-PPC_SYS_SPU(newuname)
+SYSCALL_SPU(newuname)
 SYSCALL(ni_syscall)
 COMPAT_SYS_SPU(adjtimex)
 SYSCALL_SPU(mprotect)
diff --git a/arch/powerpc/kernel/syscalls.c b/arch/powerpc/kernel/syscalls.c
index 5251221e7a5a..69d3c5d50a54 100644
--- a/arch/powerpc/kernel/syscalls.c
+++ b/arch/powerpc/kernel/syscalls.c
@@ -132,19 +132,6 @@ static inline int override_machine(char __user *mach)
         return 0;
 }
 
-long ppc_newuname(struct new_utsname __user * name)
-{
-        int err = 0;
-
-        down_read(&uts_sem);
-        if (copy_to_user(name, utsname(), sizeof(*name)))
-                err = -EFAULT;
-        up_read(&uts_sem);
-        if (!err)
-                err = override_machine(name->machine);
-        return err;
-}
-
 int sys_uname(struct old_utsname __user *name)
 {
         int err = 0;
diff --git a/arch/s390/include/asm/compat.h b/arch/s390/include/asm/compat.h
index 01a08020bc0e..104f2007f097 100644
--- a/arch/s390/include/asm/compat.h
+++ b/arch/s390/include/asm/compat.h
@@ -35,7 +35,8 @@
 
 extern long psw32_user_bits;
 
-#define COMPAT_USER_HZ  100
+#define COMPAT_USER_HZ          100
+#define COMPAT_UTS_MACHINE      "s390\0\0\0\0"
 
 typedef u32             compat_size_t;
 typedef s32             compat_ssize_t;
diff --git a/arch/s390/kernel/compat_wrapper.S b/arch/s390/kernel/compat_wrapper.S
index 30de2d0e52bb..672ce52341b4 100644
--- a/arch/s390/kernel/compat_wrapper.S
+++ b/arch/s390/kernel/compat_wrapper.S
@@ -547,7 +547,7 @@ sys32_setdomainname_wrapper:
         .globl  sys32_newuname_wrapper
 sys32_newuname_wrapper:
         llgtr   %r2,%r2                 # struct new_utsname *
-        jg      sys_s390_newuname       # branch to system call
+        jg      sys_newuname            # branch to system call
 
         .globl  compat_sys_adjtimex_wrapper
 compat_sys_adjtimex_wrapper:
diff --git a/arch/s390/kernel/entry.h b/arch/s390/kernel/entry.h
index 15fd68b196c0..eb15c12ec158 100644
--- a/arch/s390/kernel/entry.h
+++ b/arch/s390/kernel/entry.h
@@ -24,7 +24,6 @@ int __cpuinit start_secondary(void *cpuvoid);
 void __init startup_init(void);
 void die(const char * str, struct pt_regs * regs, long err);
 
-struct new_utsname;
 struct s390_mmap_arg_struct;
 struct fadvise64_64_args;
 struct old_sigaction;
@@ -32,7 +31,6 @@ struct old_sigaction;
 long sys_mmap2(struct s390_mmap_arg_struct __user  *arg);
 long sys_s390_ipc(uint call, int first, unsigned long second,
              unsigned long third, void __user *ptr);
-long sys_s390_newuname(struct new_utsname __user *name);
 long sys_s390_personality(unsigned long personality);
 long sys_s390_fadvise64(int fd, u32 offset_high, u32 offset_low,
                     size_t len, int advice);
diff --git a/arch/s390/kernel/sys_s390.c b/arch/s390/kernel/sys_s390.c
index b8b78092ab7c..7b6b0f81a283 100644
--- a/arch/s390/kernel/sys_s390.c
+++ b/arch/s390/kernel/sys_s390.c
@@ -131,17 +131,6 @@ SYSCALL_DEFINE5(s390_ipc, uint, call, int, first, unsigned long, second,
 }
 
 #ifdef CONFIG_64BIT
-SYSCALL_DEFINE1(s390_newuname, struct new_utsname __user *, name)
-{
-        int ret = sys_newuname(name);
-
-        if (personality(current->personality) == PER_LINUX32 && !ret) {
-                ret = copy_to_user(name->machine, "s390\0\0\0\0", 8);
-                if (ret) ret = -EFAULT;
-        }
-        return ret;
-}
-
 SYSCALL_DEFINE1(s390_personality, unsigned long, personality)
 {
         int ret;
diff --git a/arch/s390/kernel/syscalls.S b/arch/s390/kernel/syscalls.S
index 990ac8b321c8..201ce6bed34e 100644
--- a/arch/s390/kernel/syscalls.S
+++ b/arch/s390/kernel/syscalls.S
@@ -130,7 +130,7 @@ SYSCALL(sys_fsync,sys_fsync,sys32_fsync_wrapper)
 SYSCALL(sys_sigreturn,sys_sigreturn,sys32_sigreturn)
 SYSCALL(sys_clone,sys_clone,sys_clone_wrapper)                  /* 120 */
 SYSCALL(sys_setdomainname,sys_setdomainname,sys32_setdomainname_wrapper)
-SYSCALL(sys_newuname,sys_s390_newuname,sys32_newuname_wrapper)
+SYSCALL(sys_newuname,sys_newuname,sys32_newuname_wrapper)
 NI_SYSCALL                                                      /* modify_ldt for i386 */
 SYSCALL(sys_adjtimex,sys_adjtimex,compat_sys_adjtimex_wrapper)
 SYSCALL(sys_mprotect,sys_mprotect,sys32_mprotect_wrapper)       /* 125 */
diff --git a/arch/sparc/include/asm/compat.h b/arch/sparc/include/asm/compat.h
index 0e706257918f..5016f76ea98a 100644
--- a/arch/sparc/include/asm/compat.h
+++ b/arch/sparc/include/asm/compat.h
@@ -5,7 +5,8 @@
  */
 #include <linux/types.h>
 
-#define COMPAT_USER_HZ  100
+#define COMPAT_USER_HZ          100
+#define COMPAT_UTS_MACHINE      "sparc\0\0"
 
 typedef u32             compat_size_t;
 typedef s32             compat_ssize_t;
diff --git a/arch/sparc/kernel/sys_sparc_64.c b/arch/sparc/kernel/sys_sparc_64.c
index 45410e939628..3d435c42e6db 100644
--- a/arch/sparc/kernel/sys_sparc_64.c
+++ b/arch/sparc/kernel/sys_sparc_64.c
@@ -510,17 +510,6 @@ out:
         return err;
 }
 
-SYSCALL_DEFINE1(sparc64_newuname, struct new_utsname __user *, name)
-{
-        int ret = sys_newuname(name);
-        
-        if (current->personality == PER_LINUX32 && !ret) {
-                ret = (copy_to_user(name->machine, "sparc\0\0", 8)
-                       ? -EFAULT : 0);
-        }
-        return ret;
-}
-
 SYSCALL_DEFINE1(sparc64_personality, unsigned long, personality)
 {
         int ret;
diff --git a/arch/sparc/kernel/systbls.h b/arch/sparc/kernel/systbls.h
index 2c331c37e748..118759cd7342 100644
--- a/arch/sparc/kernel/systbls.h
+++ b/arch/sparc/kernel/systbls.h
@@ -6,15 +6,12 @@
 #include <asm/utrap.h>
 #include <asm/signal.h>
 
-struct new_utsname;
-
 extern asmlinkage unsigned long sys_getpagesize(void);
 extern asmlinkage long sparc_pipe(struct pt_regs *regs);
 extern asmlinkage long sys_sparc_ipc(unsigned int call, int first,
                                unsigned long second,
                                unsigned long third,
                                void __user *ptr, long fifth);
-extern asmlinkage long sparc64_newuname(struct new_utsname __user *name);
 extern asmlinkage long sparc64_personality(unsigned long personality);
 extern asmlinkage long sys64_munmap(unsigned long addr, size_t len);
 extern asmlinkage unsigned long sys64_mremap(unsigned long addr,
diff --git a/arch/sparc/kernel/systbls_64.S b/arch/sparc/kernel/systbls_64.S
index 30ca2b1d3a17..9db058dd039e 100644
--- a/arch/sparc/kernel/systbls_64.S
+++ b/arch/sparc/kernel/systbls_64.S
@@ -55,7 +55,7 @@ sys_call_table32:
 /*170*/ .word sys32_lsetxattr, sys32_fsetxattr, sys_getxattr, sys_lgetxattr, compat_sys_getdents
         .word sys_setsid, sys_fchdir, sys32_fgetxattr, sys_listxattr, sys_llistxattr
 /*180*/ .word sys32_flistxattr, sys_removexattr, sys_lremovexattr, compat_sys_sigpending, sys_ni_syscall
-        .word sys32_setpgid, sys32_fremovexattr, sys32_tkill, sys32_exit_group, sys_sparc64_newuname
+        .word sys32_setpgid, sys32_fremovexattr, sys32_tkill, sys32_exit_group, sys_newuname
 /*190*/ .word sys32_init_module, sys_sparc64_personality, sys_remap_file_pages, sys32_epoll_create, sys32_epoll_ctl
         .word sys32_epoll_wait, sys32_ioprio_set, sys_getppid, sys32_sigaction, sys_sgetmask
 /*200*/ .word sys32_ssetmask, sys_sigsuspend, compat_sys_newlstat, sys_uselib, compat_sys_old_readdir
@@ -130,7 +130,7 @@ sys_call_table:
 /*170*/ .word sys_lsetxattr, sys_fsetxattr, sys_getxattr, sys_lgetxattr, sys_getdents
         .word sys_setsid, sys_fchdir, sys_fgetxattr, sys_listxattr, sys_llistxattr
 /*180*/ .word sys_flistxattr, sys_removexattr, sys_lremovexattr, sys_nis_syscall, sys_ni_syscall
-        .word sys_setpgid, sys_fremovexattr, sys_tkill, sys_exit_group, sys_sparc64_newuname
+        .word sys_setpgid, sys_fremovexattr, sys_tkill, sys_exit_group, sys_newuname
 /*190*/ .word sys_init_module, sys_sparc64_personality, sys_remap_file_pages, sys_epoll_create, sys_epoll_ctl
         .word sys_epoll_wait, sys_ioprio_set, sys_getppid, sys_nis_syscall, sys_sgetmask
 /*200*/ .word sys_ssetmask, sys_nis_syscall, sys_newlstat, sys_uselib, sys_nis_syscall
diff --git a/arch/um/sys-x86_64/syscall_table.c b/arch/um/sys-x86_64/syscall_table.c
index dd21d69715e6..47d469e7e7ce 100644
--- a/arch/um/sys-x86_64/syscall_table.c
+++ b/arch/um/sys-x86_64/syscall_table.c
@@ -26,11 +26,6 @@
 
 /* On UML we call it this way ("old" means it's not mmap2) */
 #define sys_mmap old_mmap
-/*
- * On x86-64 sys_uname is actually sys_newuname plus a compatibility trick.
- * See arch/x86_64/kernel/sys_x86_64.c
- */
-#define sys_uname sys_uname64
 
 #define stub_clone sys_clone
 #define stub_fork sys_fork
diff --git a/arch/um/sys-x86_64/syscalls.c b/arch/um/sys-x86_64/syscalls.c
index f1199fd34d38..f3d82bb6e15a 100644
--- a/arch/um/sys-x86_64/syscalls.c
+++ b/arch/um/sys-x86_64/syscalls.c
@@ -12,20 +12,6 @@
 #include "asm/uaccess.h"
 #include "os.h"
 
-asmlinkage long sys_uname64(struct new_utsname __user * name)
-{
-        int err;
-
-        down_read(&uts_sem);
-        err = copy_to_user(name, utsname(), sizeof (*name));
-        up_read(&uts_sem);
-
-        if (personality(current->personality) == PER_LINUX32)
-                err |= copy_to_user(&name->machine, "i686", 5);
-
-        return err ? -EFAULT : 0;
-}
-
 long arch_prctl(struct task_struct *task, int code, unsigned long __user *addr)
 {
         unsigned long *ptr = addr, tmp;
diff --git a/arch/x86/include/asm/compat.h b/arch/x86/include/asm/compat.h
index 9a9c7bdc923d..306160e58b48 100644
--- a/arch/x86/include/asm/compat.h
+++ b/arch/x86/include/asm/compat.h
@@ -8,7 +8,8 @@
 #include <linux/sched.h>
 #include <asm/user32.h>
 
-#define COMPAT_USER_HZ  100
+#define COMPAT_USER_HZ          100
+#define COMPAT_UTS_MACHINE      "i686\0\0"
 
 typedef u32             compat_size_t;
 typedef s32             compat_ssize_t;
diff --git a/arch/x86/include/asm/syscalls.h b/arch/x86/include/asm/syscalls.h
index 50f6a569f0d1..47cd606c3537 100644
--- a/arch/x86/include/asm/syscalls.h
+++ b/arch/x86/include/asm/syscalls.h
@@ -68,11 +68,8 @@ int sys_vm86(unsigned long, unsigned long, struct pt_regs *);
 long sys_arch_prctl(int, unsigned long);
 
 /* kernel/sys_x86_64.c */
-struct new_utsname;
-
 asmlinkage long sys_mmap(unsigned long, unsigned long, unsigned long,
                          unsigned long, unsigned long, unsigned long);
-asmlinkage long sys_uname(struct new_utsname __user *);
 
 #endif /* CONFIG_X86_32 */
 #endif /* _ASM_X86_SYSCALLS_H */
diff --git a/arch/x86/include/asm/unistd_64.h b/arch/x86/include/asm/unistd_64.h
index 4843f7ba754a..83e2d6dc5038 100644
--- a/arch/x86/include/asm/unistd_64.h
+++ b/arch/x86/include/asm/unistd_64.h
@@ -146,7 +146,7 @@ __SYSCALL(__NR_wait4, sys_wait4)
 #define __NR_kill                               62
 __SYSCALL(__NR_kill, sys_kill)
 #define __NR_uname                              63
-__SYSCALL(__NR_uname, sys_uname)
+__SYSCALL(__NR_uname, sys_newuname)
 
 #define __NR_semget                             64
 __SYSCALL(__NR_semget, sys_semget)
diff --git a/arch/x86/kernel/sys_x86_64.c b/arch/x86/kernel/sys_x86_64.c
index 8aa2057efd12..ff14a5044ce6 100644
--- a/arch/x86/kernel/sys_x86_64.c
+++ b/arch/x86/kernel/sys_x86_64.c
@@ -209,15 +209,3 @@ bottomup:
 
         return addr;
 }
-
-
-SYSCALL_DEFINE1(uname, struct new_utsname __user *, name)
-{
-        int err;
-        down_read(&uts_sem);
-        err = copy_to_user(name, utsname(), sizeof(*name));
-        up_read(&uts_sem);
-        if (personality(current->personality) == PER_LINUX32)
-                err |= copy_to_user(&name->machine, "i686", 5);
-        return err ? -EFAULT : 0;
-}