From 858259cf7d1c443c836a2022b78cb281f0a9b95e Mon Sep 17 00:00:00 2001 From: Bodo Stroesser Date: Mon, 7 Nov 2005 00:58:55 -0800 Subject: [PATCH] uml: maintain own LDT entries Patch imlements full LDT handling in SKAS: * UML holds it's own LDT table, used to deliver data on modify_ldt(READ) * UML disables the default_ldt, inherited from the host (SKAS3) or resets LDT entries, set by host's clib and inherited in SKAS0 * A new global variable skas_needs_stub is inserted, that can be used to decide, whether stub-pages must be supported or not. * Uses the syscall-stub to replace missing PTRACE_LDT (therefore, write_ldt_entry needs to be modified) Signed-off-by: Bodo Stroesser Signed-off-by: Jeff Dike Cc: Paolo Giarrusso Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- arch/um/sys-x86_64/Makefile | 5 +-- arch/um/sys-x86_64/syscalls.c | 75 ------------------------------------------- 2 files changed, 3 insertions(+), 77 deletions(-) (limited to 'arch/um/sys-x86_64') diff --git a/arch/um/sys-x86_64/Makefile b/arch/um/sys-x86_64/Makefile index 06c3633457a2..ea977df395a1 100644 --- a/arch/um/sys-x86_64/Makefile +++ b/arch/um/sys-x86_64/Makefile @@ -5,7 +5,7 @@ # #XXX: why into lib-y? -lib-y = bitops.o bugs.o csum-partial.o delay.o fault.o mem.o memcpy.o \ +lib-y = bitops.o bugs.o csum-partial.o delay.o fault.o ldt.o mem.o memcpy.o \ ptrace.o ptrace_user.o sigcontext.o signal.o stub.o \ stub_segv.o syscalls.o syscall_table.o sysrq.o thunk.o @@ -14,7 +14,7 @@ obj-$(CONFIG_MODULES) += module.o um_module.o USER_OBJS := ptrace_user.o sigcontext.o -SYMLINKS = bitops.c csum-copy.S csum-partial.c csum-wrappers.c memcpy.S \ +SYMLINKS = bitops.c csum-copy.S csum-partial.c csum-wrappers.c ldt.c memcpy.S \ thunk.S module.c include arch/um/scripts/Makefile.rules @@ -23,6 +23,7 @@ bitops.c-dir = lib csum-copy.S-dir = lib csum-partial.c-dir = lib csum-wrappers.c-dir = lib +ldt.c-dir = /arch/um/sys-i386 memcpy.S-dir = lib thunk.S-dir = lib module.c-dir = kernel diff --git a/arch/um/sys-x86_64/syscalls.c b/arch/um/sys-x86_64/syscalls.c index 3259a4db4534..6acee5c4ada6 100644 --- a/arch/um/sys-x86_64/syscalls.c +++ b/arch/um/sys-x86_64/syscalls.c @@ -28,81 +28,6 @@ asmlinkage long sys_uname64(struct new_utsname __user * name) return err ? -EFAULT : 0; } -#ifdef CONFIG_MODE_TT -extern int modify_ldt(int func, void *ptr, unsigned long bytecount); - -long sys_modify_ldt_tt(int func, void *ptr, unsigned long bytecount) -{ - /* XXX This should check VERIFY_WRITE depending on func, check this - * in i386 as well. - */ - if (!access_ok(VERIFY_READ, ptr, bytecount)) - return -EFAULT; - return(modify_ldt(func, ptr, bytecount)); -} -#endif - -#ifdef CONFIG_MODE_SKAS -extern int userspace_pid[]; - -#include "skas_ptrace.h" - -long sys_modify_ldt_skas(int func, void *ptr, unsigned long bytecount) -{ - struct ptrace_ldt ldt; - void *buf; - int res, n; - - buf = kmalloc(bytecount, GFP_KERNEL); - if(buf == NULL) - return(-ENOMEM); - - res = 0; - - switch(func){ - case 1: - case 0x11: - res = copy_from_user(buf, ptr, bytecount); - break; - } - - if(res != 0){ - res = -EFAULT; - goto out; - } - - ldt = ((struct ptrace_ldt) { .func = func, - .ptr = buf, - .bytecount = bytecount }); -#warning Need to look up userspace_pid by cpu - res = ptrace(PTRACE_LDT, userspace_pid[0], 0, (unsigned long) &ldt); - if(res < 0) - goto out; - - switch(func){ - case 0: - case 2: - n = res; - res = copy_to_user(ptr, buf, n); - if(res != 0) - res = -EFAULT; - else - res = n; - break; - } - - out: - kfree(buf); - return(res); -} -#endif - -long sys_modify_ldt(int func, void *ptr, unsigned long bytecount) -{ - return(CHOOSE_MODE_PROC(sys_modify_ldt_tt, sys_modify_ldt_skas, func, - ptr, bytecount)); -} - #ifdef CONFIG_MODE_TT extern long arch_prctl(int code, unsigned long addr); -- cgit v1.2.2