x86: compat_binfmt_elf

This switches x86-64's 32-bit ELF support to use the shared
fs/compat_binfmt_elf.c code instead of our own ia32_binfmt.c.

Signed-off-by: Roland McGrath <roland@redhat.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>

diff --git a/arch/x86/Kconfig b/arch/x86/Kconfig
index 1992b8fe6a2f5705949344405dc90cdef6d06d26..d89b9452815307b34d56cee362487f12fb706cc5 100644 (file)
--- a/arch/x86/Kconfig
+++ b/arch/x86/Kconfig
@@ -1532,6 +1532,7 @@ source "fs/Kconfig.binfmt"
 config IA32_EMULATION
        bool "IA32 Emulation"
        depends on X86_64
+       select COMPAT_BINFMT_ELF
        help
          Include code to run 32-bit programs under a 64-bit kernel. You should
          likely turn this on, unless you're 100% sure that you don't have any

diff --git a/arch/x86/ia32/Makefile b/arch/x86/ia32/Makefile
index 93a6fda65f4974d67c7e69fc524749d0aa1e12a2..52d0ccfcf6eafbc84fe0d66270b165b34101639d 100644 (file)
--- a/arch/x86/ia32/Makefile
+++ b/arch/x86/ia32/Makefile
@@ -2,8 +2,7 @@
 # Makefile for the ia32 kernel emulation subsystem.
 #
 
-obj-$(CONFIG_IA32_EMULATION) := ia32entry.o sys_ia32.o ia32_signal.o \
-       ia32_binfmt.o
+obj-$(CONFIG_IA32_EMULATION) := ia32entry.o sys_ia32.o ia32_signal.o
 
 sysv-$(CONFIG_SYSVIPC) := ipc32.o
 obj-$(CONFIG_IA32_EMULATION) += $(sysv-y)

diff --git a/arch/x86/vdso/vdso32-setup.c b/arch/x86/vdso/vdso32-setup.c
index e0feb66a2408a9f3f89e2da50e1f74dc4dca5faa..348f1341e1c8f4693c5615f9045c49244cc555bf 100644 (file)
--- a/arch/x86/vdso/vdso32-setup.c
+++ b/arch/x86/vdso/vdso32-setup.c
@@ -377,6 +377,39 @@ int arch_setup_additional_pages(struct linux_binprm *bprm, int exstack)
 
 __initcall(sysenter_setup);
 
+#ifdef CONFIG_SYSCTL
+/* Register vsyscall32 into the ABI table */
+#include <linux/sysctl.h>
+
+static ctl_table abi_table2[] = {
+       {
+               .procname       = "vsyscall32",
+               .data           = &sysctl_vsyscall32,
+               .maxlen         = sizeof(int),
+               .mode           = 0644,
+               .proc_handler   = proc_dointvec
+       },
+       {}
+};
+
+static ctl_table abi_root_table2[] = {
+       {
+               .ctl_name = CTL_ABI,
+               .procname = "abi",
+               .mode = 0555,
+               .child = abi_table2
+       },
+       {}
+};
+
+static __init int ia32_binfmt_init(void)
+{
+       register_sysctl_table(abi_root_table2);
+       return 0;
+}
+__initcall(ia32_binfmt_init);
+#endif
+
 #else  /* CONFIG_X86_32 */
 
 const char *arch_vma_name(struct vm_area_struct *vma)

diff --git a/include/asm-x86/elf.h b/include/asm-x86/elf.h
index d6bf7421d7b09bb5e01e72701cd5496ccd559884..dab4744f958612f6a86b7ecbc369c010ee4dfa6c 100644 (file)
--- a/include/asm-x86/elf.h
+++ b/include/asm-x86/elf.h
@@ -73,6 +73,9 @@ typedef struct user_fxsr_struct elf_fpxregset_t;
 #endif
 
 #ifdef __KERNEL__
+#include <asm/vdso.h>
+
+extern unsigned int vdso_enabled;
 
 /*
  * This is used to ensure we don't load something for the wrong architecture.
@@ -84,7 +87,6 @@ typedef struct user_fxsr_struct elf_fpxregset_t;
 #include <asm/processor.h>
 #include <asm/system.h>                /* for savesegment */
 #include <asm/desc.h>
-#include <asm/vdso.h>
 
 #define elf_check_arch(x)      elf_check_arch_ia32(x)
 
@@ -106,7 +108,6 @@ typedef struct user_fxsr_struct elf_fpxregset_t;
 
 #define ELF_PLATFORM   (utsname()->machine)
 #define set_personality_64bit()        do { } while (0)
-extern unsigned int vdso_enabled;
 
 #else /* CONFIG_X86_32 */
 
@@ -118,29 +119,57 @@ extern unsigned int vdso_enabled;
 #define elf_check_arch(x) \
        ((x)->e_machine == EM_X86_64)
 
+#define compat_elf_check_arch(x)       elf_check_arch_ia32(x)
+
+static inline void start_ia32_thread(struct pt_regs *regs, u32 ip, u32 sp)
+{
+       asm volatile("movl %0,%%fs" :: "r" (0));
+       asm volatile("movl %0,%%es; movl %0,%%ds" : : "r" (__USER32_DS));
+       load_gs_index(0);
+       regs->ip = ip;
+       regs->sp = sp;
+       regs->flags = X86_EFLAGS_IF;
+       regs->cs = __USER32_CS;
+       regs->ss = __USER32_DS;
+}
+
+static inline void elf_common_init(struct thread_struct *t,
+                                  struct pt_regs *regs, const u16 ds)
+{
+       regs->ax = regs->bx = regs->cx = regs->dx = 0;
+       regs->si = regs->di = regs->bp = 0;
+       regs->r8 = regs->r9 = regs->r10 = regs->r11 = 0;
+       regs->r12 = regs->r13 = regs->r14 = regs->r15 = 0;
+       t->fs = t->gs = 0;
+       t->fsindex = t->gsindex = 0;
+       t->ds = t->es = ds;
+}
+
 #define ELF_PLAT_INIT(_r, load_addr)   do {              \
-       struct task_struct *cur = current;                \
-       (_r)->bx = 0; (_r)->cx = 0; (_r)->dx = 0;         \
-       (_r)->si = 0; (_r)->di = 0; (_r)->bp = 0;         \
-       (_r)->ax = 0;                                     \
-       (_r)->r8 = 0;                                     \
-       (_r)->r9 = 0;                                     \
-       (_r)->r10 = 0;                                    \
-       (_r)->r11 = 0;                                    \
-       (_r)->r12 = 0;                                    \
-       (_r)->r13 = 0;                                    \
-       (_r)->r14 = 0;                                    \
-       (_r)->r15 = 0;                                    \
-       cur->thread.fs = 0; cur->thread.gs = 0;           \
-       cur->thread.fsindex = 0; cur->thread.gsindex = 0; \
-       cur->thread.ds = 0; cur->thread.es = 0;           \
+       elf_common_init(&current->thread, _r, 0);         \
        clear_thread_flag(TIF_IA32);                      \
 } while (0)
 
+#define        COMPAT_ELF_PLAT_INIT(regs, load_addr)   \
+       elf_common_init(&current->thread, regs, __USER_DS)
+#define        compat_start_thread(regs, ip, sp)       do {            \
+               start_ia32_thread(regs, ip, sp);                \
+               set_fs(USER_DS);                                \
+       } while (0)
+#define COMPAT_SET_PERSONALITY(ex, ibcs2)      do {            \
+               if (test_thread_flag(TIF_IA32))                 \
+                       clear_thread_flag(TIF_ABI_PENDING);     \
+               else                                            \
+                       set_thread_flag(TIF_ABI_PENDING);       \
+               current->personality |= force_personality32;    \
+       } while (0)
+#define COMPAT_ELF_PLATFORM                    ("i686")
+
 /* I'm not sure if we can use '-' here */
 #define ELF_PLATFORM       ("x86_64")
 extern void set_personality_64bit(void);
-extern int vdso_enabled;
+extern unsigned int sysctl_vsyscall32;
+extern int force_personality32;
 
 #endif /* !CONFIG_X86_32 */
 
@@ -179,17 +208,19 @@ extern int vdso_enabled;
 
 struct task_struct;
 
+#define        ARCH_DLINFO_IA32(vdso_enabled) \
+do if (vdso_enabled) {                                                 \
+               NEW_AUX_ENT(AT_SYSINFO, VDSO_ENTRY);                    \
+               NEW_AUX_ENT(AT_SYSINFO_EHDR, VDSO_CURRENT_BASE);        \
+} while (0)
+
 #ifdef CONFIG_X86_32
 
 #define VDSO_HIGH_BASE         (__fix_to_virt(FIX_VDSO))
 
-/* update AT_VECTOR_SIZE_ARCH if the number of NEW_AUX_ENT entries changes */
+#define ARCH_DLINFO            ARCH_DLINFO_IA32(vdso_enabled)
 
-#define ARCH_DLINFO \
-do if (vdso_enabled) {                                                 \
-               NEW_AUX_ENT(AT_SYSINFO, VDSO_ENTRY);                    \
-               NEW_AUX_ENT(AT_SYSINFO_EHDR, VDSO_CURRENT_BASE);        \
-} while (0)
+/* update AT_VECTOR_SIZE_ARCH if the number of NEW_AUX_ENT entries changes */
 
 #else /* CONFIG_X86_32 */
 
@@ -203,6 +234,12 @@ do if (vdso_enabled) {                                             \
        NEW_AUX_ENT(AT_SYSINFO_EHDR,(unsigned long)current->mm->context.vdso);\
 } while (0)
 
+#define AT_SYSINFO             32
+
+#define COMPAT_ARCH_DLINFO     ARCH_DLINFO_IA32(sysctl_vsyscall32)
+
+#define COMPAT_ELF_ET_DYN_BASE (TASK_UNMAPPED_BASE + 0x1000000)
+
 #endif /* !CONFIG_X86_32 */
 
 #define VDSO_CURRENT_BASE      ((unsigned long)current->mm->context.vdso)
@@ -216,6 +253,9 @@ struct linux_binprm;
 extern int arch_setup_additional_pages(struct linux_binprm *bprm,
                                       int executable_stack);
 
+extern int syscall32_setup_pages(struct linux_binprm *, int exstack);
+#define compat_arch_setup_additional_pages     syscall32_setup_pages
+
 extern unsigned long arch_randomize_brk(struct mm_struct *mm);
 #define arch_randomize_brk arch_randomize_brk