#include <linux/smp_lock.h>
#include <linux/errno.h>
#include <linux/ptrace.h>
+#include <linux/tracehook.h>
#include <linux/user.h>
#include <linux/security.h>
#include <linux/audit.h>
+#include <linux/seccomp.h>
+#include <linux/signal.h>
+#include <linux/module.h>
+#include <asm/tracehook.h>
#include <asm/uaccess.h>
#include <asm/pgtable.h>
#include <asm/system.h>
#include <asm/ldt.h>
#include <asm/desc.h>
+
/*
- * does not yet catch signals sent when the child dies.
- * in exit.c or in signal.c.
+ * Determines which flags the user has access to [1 = access, 0 = no access].
+ * Prohibits changing ID(21), VIP(20), VIF(19), VM(17), NT(14), IOPL(12-13), IF(9).
+ * Also masks reserved bits (31-22, 15, 5, 3, 1).
*/
-
-/* determines which flags the user has access to. */
-/* 1 = access 0 = no access */
-#define FLAG_MASK 0x00044dd5
-
-/* set's the trap flag. */
-#define TRAP_FLAG 0x100
+#define FLAG_MASK 0x00050dd5
/*
* Offset of eflags on child stack..
*/
-#define EFL_OFFSET ((EFL-2)*4-sizeof(struct pt_regs))
+#define EFL_OFFSET offsetof(struct pt_regs, eflags)
+
+static inline struct pt_regs *get_child_regs(struct task_struct *task)
+{
+ void *stack_top = (void *)task->thread.esp0;
+ return stack_top - sizeof(struct pt_regs);
+}
/*
- * this routine will get a word off of the processes privileged stack.
- * the offset is how far from the base addr as stored in the TSS.
- * this routine assumes that all the privileged stacks are in our
+ * This routine will get a word off of the processes privileged stack.
+ * the offset is bytes into the pt_regs structure on the stack.
+ * This routine assumes that all the privileged stacks are in our
* data space.
*/
static inline int get_stack_long(struct task_struct *task, int offset)
{
unsigned char *stack;
- stack = (unsigned char *)task->thread.esp0;
+ stack = (unsigned char *)task->thread.esp0 - sizeof(struct pt_regs);
stack += offset;
return (*((int *)stack));
}
/*
- * this routine will put a word on the processes privileged stack.
- * the offset is how far from the base addr as stored in the TSS.
- * this routine assumes that all the privileged stacks are in our
+ * This routine will put a word on the processes privileged stack.
+ * the offset is bytes into the pt_regs structure on the stack.
+ * This routine assumes that all the privileged stacks are in our
* data space.
*/
static inline int put_stack_long(struct task_struct *task, int offset,
{
unsigned char * stack;
- stack = (unsigned char *) task->thread.esp0;
+ stack = (unsigned char *)task->thread.esp0 - sizeof(struct pt_regs);
stack += offset;
*(unsigned long *) stack = data;
return 0;
return -EIO;
child->thread.fs = value;
return 0;
- case GS:
- if (value && (value & 3) != 3)
- return -EIO;
- child->thread.gs = value;
- return 0;
case DS:
case ES:
+ case GS:
if (value && (value & 3) != 3)
return -EIO;
value &= 0xffff;
case EFL:
value &= FLAG_MASK;
value |= get_stack_long(child, EFL_OFFSET) & ~FLAG_MASK;
+ clear_tsk_thread_flag(child, TIF_FORCED_TF);
break;
}
- if (regno > GS*4)
- regno -= 2*4;
- put_stack_long(child, regno - sizeof(struct pt_regs), value);
+ if (regno > ES*4)
+ regno -= 1*4;
+ put_stack_long(child, regno, value);
return 0;
}
case FS:
retval = child->thread.fs;
break;
- case GS:
- retval = child->thread.gs;
- break;
+ case EFL:
+ if (test_tsk_thread_flag(child, TIF_FORCED_TF))
+ retval &= ~X86_EFLAGS_TF;
+ goto fetch;
case DS:
case ES:
+ case GS:
case SS:
case CS:
retval = 0xffff;
/* fall through */
default:
- if (regno > GS*4)
- regno -= 2*4;
- regno = regno - sizeof(struct pt_regs);
+fetch:
+ if (regno > ES*4)
+ regno -= 1*4;
retval &= get_stack_long(child, regno);
+ break;
}
return retval;
}
-/*
- * Called by kernel/ptrace.c when detaching..
- *
- * Make sure the single step bit is not set.
- */
-void ptrace_disable(struct task_struct *child)
-{
- long tmp;
+#define LDT_SEGMENT 4
+
+static unsigned long convert_eip_to_linear(struct task_struct *child, struct pt_regs *regs)
+{
+ unsigned long addr, seg;
+
+ addr = regs->eip;
+ seg = regs->xcs & 0xffff;
+ if (regs->eflags & VM_MASK) {
+ addr = (addr & 0xffff) + (seg << 4);
+ return addr;
+ }
- tmp = get_stack_long(child, EFL_OFFSET) & ~TRAP_FLAG;
- put_stack_long(child, EFL_OFFSET, tmp);
+ /*
+ * We'll assume that the code segments in the GDT
+ * are all zero-based. That is largely true: the
+ * TLS segments are used for data, and the PNPBIOS
+ * and APM bios ones we just ignore here.
+ */
+ if (seg & LDT_SEGMENT) {
+ u32 *desc;
+ unsigned long base;
+
+ down(&child->mm->context.sem);
+ desc = child->mm->context.ldt + (seg & ~7);
+ base = (desc[0] >> 16) | ((desc[1] & 0xff) << 16) | (desc[1] & 0xff000000);
+
+ /* 16-bit code segment? */
+ if (!((desc[1] >> 22) & 1))
+ addr &= 0xffff;
+ addr += base;
+ up(&child->mm->context.sem);
+ }
+ return addr;
}
-/*
- * Perform get_thread_area on behalf of the traced child.
- */
-static int
-ptrace_get_thread_area(struct task_struct *child,
- int idx, struct user_desc __user *user_desc)
+static inline int is_setting_trap_flag(struct task_struct *child, struct pt_regs *regs)
{
- struct user_desc info;
- struct desc_struct *desc;
+ int i, copied;
+ unsigned char opcode[15];
+ unsigned long addr = convert_eip_to_linear(child, regs);
+
+ copied = access_process_vm(child, addr, opcode, sizeof(opcode), 0);
+ for (i = 0; i < copied; i++) {
+ switch (opcode[i]) {
+ /* popf and iret */
+ case 0x9d: case 0xcf:
+ return 1;
+ /* opcode and address size prefixes */
+ case 0x66: case 0x67:
+ continue;
+ /* irrelevant prefixes (segment overrides and repeats) */
+ case 0x26: case 0x2e:
+ case 0x36: case 0x3e:
+ case 0x64: case 0x65:
+ case 0xf0: case 0xf2: case 0xf3:
+ continue;
+
+ /*
+ * pushf: NOTE! We should probably not let
+ * the user see the TF bit being set. But
+ * it's more pain than it's worth to avoid
+ * it, and a debugger could emulate this
+ * all in user space if it _really_ cares.
+ */
+ case 0x9c:
+ default:
+ return 0;
+ }
+ }
+ return 0;
+}
-/*
- * Get the current Thread-Local Storage area:
- */
+void tracehook_enable_single_step(struct task_struct *child)
+{
+ struct pt_regs *regs = get_child_regs(child);
-#define GET_BASE(desc) ( \
- (((desc)->a >> 16) & 0x0000ffff) | \
- (((desc)->b << 16) & 0x00ff0000) | \
- ( (desc)->b & 0xff000000) )
+ /*
+ * Always set TIF_SINGLESTEP - this guarantees that
+ * we single-step system calls etc.. This will also
+ * cause us to set TF when returning to user mode.
+ */
+ set_tsk_thread_flag(child, TIF_SINGLESTEP);
-#define GET_LIMIT(desc) ( \
- ((desc)->a & 0x0ffff) | \
- ((desc)->b & 0xf0000) )
+ /*
+ * If TF was already set, don't do anything else
+ */
+ if (regs->eflags & X86_EFLAGS_TF)
+ return;
-#define GET_32BIT(desc) (((desc)->b >> 22) & 1)
-#define GET_CONTENTS(desc) (((desc)->b >> 10) & 3)
-#define GET_WRITABLE(desc) (((desc)->b >> 9) & 1)
-#define GET_LIMIT_PAGES(desc) (((desc)->b >> 23) & 1)
-#define GET_PRESENT(desc) (((desc)->b >> 15) & 1)
-#define GET_USEABLE(desc) (((desc)->b >> 20) & 1)
+ /* Set TF on the kernel stack.. */
+ regs->eflags |= X86_EFLAGS_TF;
- if (idx < GDT_ENTRY_TLS_MIN || idx > GDT_ENTRY_TLS_MAX)
- return -EINVAL;
+ /*
+ * ..but if TF is changed by the instruction we will trace,
+ * don't mark it as being "us" that set it, so that we
+ * won't clear it by hand later.
+ */
+ if (is_setting_trap_flag(child, regs))
+ return;
+
+ set_tsk_thread_flag(child, TIF_FORCED_TF);
+}
- desc = child->thread.tls_array + idx - GDT_ENTRY_TLS_MIN;
+void tracehook_disable_single_step(struct task_struct *child)
+{
+ /* Always clear TIF_SINGLESTEP... */
+ clear_tsk_thread_flag(child, TIF_SINGLESTEP);
- info.entry_number = idx;
- info.base_addr = GET_BASE(desc);
- info.limit = GET_LIMIT(desc);
- info.seg_32bit = GET_32BIT(desc);
- info.contents = GET_CONTENTS(desc);
- info.read_exec_only = !GET_WRITABLE(desc);
- info.limit_in_pages = GET_LIMIT_PAGES(desc);
- info.seg_not_present = !GET_PRESENT(desc);
- info.useable = GET_USEABLE(desc);
+ /* But touch TF only if it was set by us.. */
+ if (test_and_clear_tsk_thread_flag(child, TIF_FORCED_TF)) {
+ struct pt_regs *regs = get_child_regs(child);
+ regs->eflags &= ~X86_EFLAGS_TF;
+ }
+}
- if (copy_to_user(user_desc, &info, sizeof(info)))
- return -EFAULT;
+
+static int
+genregs_get(struct task_struct *target,
+ const struct utrace_regset *regset,
+ unsigned int pos, unsigned int count,
+ void *kbuf, void __user *ubuf)
+{
+ if (kbuf) {
+ unsigned long *kp = kbuf;
+ while (count > 0) {
+ *kp++ = getreg(target, pos);
+ pos += 4;
+ count -= 4;
+ }
+ }
+ else {
+ unsigned long __user *up = ubuf;
+ while (count > 0) {
+ if (__put_user(getreg(target, pos), up++))
+ return -EFAULT;
+ pos += 4;
+ count -= 4;
+ }
+ }
return 0;
}
-/*
- * Perform set_thread_area on behalf of the traced child.
- */
static int
-ptrace_set_thread_area(struct task_struct *child,
- int idx, struct user_desc __user *user_desc)
+genregs_set(struct task_struct *target,
+ const struct utrace_regset *regset,
+ unsigned int pos, unsigned int count,
+ const void *kbuf, const void __user *ubuf)
{
- struct user_desc info;
- struct desc_struct *desc;
+ int ret = 0;
+
+ if (kbuf) {
+ const unsigned long *kp = kbuf;
+ while (!ret && count > 0) {
+ ret = putreg(target, pos, *kp++);
+ pos += 4;
+ count -= 4;
+ }
+ }
+ else {
+ int ret = 0;
+ const unsigned long __user *up = ubuf;
+ while (!ret && count > 0) {
+ unsigned long val;
+ ret = __get_user(val, up++);
+ if (!ret)
+ ret = putreg(target, pos, val);
+ pos += 4;
+ count -= 4;
+ }
+ }
- if (copy_from_user(&info, user_desc, sizeof(info)))
- return -EFAULT;
+ return ret;
+}
- if (idx < GDT_ENTRY_TLS_MIN || idx > GDT_ENTRY_TLS_MAX)
- return -EINVAL;
+static int
+fpregs_active(struct task_struct *target, const struct utrace_regset *regset)
+{
+ return tsk_used_math(target) ? regset->n : 0;
+}
- desc = child->thread.tls_array + idx - GDT_ENTRY_TLS_MIN;
- if (LDT_empty(&info)) {
- desc->a = 0;
- desc->b = 0;
- } else {
- desc->a = LDT_entry_a(&info);
- desc->b = LDT_entry_b(&info);
+static int
+fpregs_get(struct task_struct *target,
+ const struct utrace_regset *regset,
+ unsigned int pos, unsigned int count,
+ void *kbuf, void __user *ubuf)
+{
+ struct user_i387_struct fp;
+ int ret;
+
+ if (tsk_used_math(target)) {
+ if (target == current)
+ unlazy_fpu(target);
}
+ else
+ init_fpu(target);
- return 0;
+ ret = get_fpregs(&fp, target);
+ if (ret == 0)
+ ret = utrace_regset_copyout(&pos, &count, &kbuf, &ubuf,
+ &fp, 0, -1);
+
+ return ret;
}
-asmlinkage int sys_ptrace(long request, long pid, long addr, long data)
+static int
+fpregs_set(struct task_struct *target,
+ const struct utrace_regset *regset,
+ unsigned int pos, unsigned int count,
+ const void *kbuf, const void __user *ubuf)
{
- struct task_struct *child;
- struct user * dummy = NULL;
- int i, ret;
- unsigned long __user *datap = (unsigned long __user *)data;
-
- lock_kernel();
- ret = -EPERM;
- if (request == PTRACE_TRACEME) {
- /* are we already being traced? */
- if (current->ptrace & PT_PTRACED)
- goto out;
- ret = security_ptrace(current->parent, current);
+ struct user_i387_struct fp;
+ int ret;
+
+ if (tsk_used_math(target)) {
+ if (target == current)
+ unlazy_fpu(target);
+ }
+ else if (pos == 0 && count == sizeof(fp))
+ set_stopped_child_used_math(target);
+ else
+ init_fpu(target);
+
+ if (pos > 0 || count < sizeof(fp)) {
+ ret = get_fpregs(&fp, target);
+ if (ret == 0)
+ ret = utrace_regset_copyin(&pos, &count, &kbuf, &ubuf,
+ &fp, 0, -1);
if (ret)
- goto out;
- /* set the ptrace bit in the process flags. */
- current->ptrace |= PT_PTRACED;
- ret = 0;
- goto out;
+ return ret;
+ kbuf = &fp;
}
- ret = -ESRCH;
- read_lock(&tasklist_lock);
- child = find_task_by_pid(pid);
- if (child)
- get_task_struct(child);
- read_unlock(&tasklist_lock);
- if (!child)
- goto out;
-
- ret = -EPERM;
- if (pid == 1) /* you may not mess with init */
- goto out_tsk;
-
- if (request == PTRACE_ATTACH) {
- ret = ptrace_attach(child);
- goto out_tsk;
+ else if (kbuf == NULL) {
+ if (__copy_from_user(&fp, ubuf, sizeof(fp)))
+ return -EFAULT;
+ kbuf = &fp;
}
- ret = ptrace_check_attach(child, request == PTRACE_KILL);
- if (ret < 0)
- goto out_tsk;
+ return set_fpregs(target, kbuf);
+}
- switch (request) {
- /* when I and D space are separate, these will need to be fixed. */
- case PTRACE_PEEKTEXT: /* read word at location addr. */
- case PTRACE_PEEKDATA: {
- unsigned long tmp;
- int copied;
+static int
+fpxregs_active(struct task_struct *target, const struct utrace_regset *regset)
+{
+ return !cpu_has_fxsr ? -ENODEV : tsk_used_math(target) ? regset->n : 0;
+}
- copied = access_process_vm(child, addr, &tmp, sizeof(tmp), 0);
- ret = -EIO;
- if (copied != sizeof(tmp))
- break;
- ret = put_user(tmp, datap);
- break;
- }
+static int
+fpxregs_get(struct task_struct *target,
+ const struct utrace_regset *regset,
+ unsigned int pos, unsigned int count,
+ void *kbuf, void __user *ubuf)
+{
+ if (!cpu_has_fxsr)
+ return -ENODEV;
- /* read the word at location addr in the USER area. */
- case PTRACE_PEEKUSR: {
- unsigned long tmp;
+ if (tsk_used_math(target))
+ unlazy_fpu(target);
+ else
+ init_fpu(target);
- ret = -EIO;
- if ((addr & 3) || addr < 0 ||
- addr > sizeof(struct user) - 3)
- break;
+ return utrace_regset_copyout(&pos, &count, &kbuf, &ubuf,
+ &target->thread.i387.fxsave, 0, -1);
+}
- tmp = 0; /* Default return condition */
- if(addr < FRAME_SIZE*sizeof(long))
- tmp = getreg(child, addr);
- if(addr >= (long) &dummy->u_debugreg[0] &&
- addr <= (long) &dummy->u_debugreg[7]){
- addr -= (long) &dummy->u_debugreg[0];
- addr = addr >> 2;
- tmp = child->thread.debugreg[addr];
- }
- ret = put_user(tmp, datap);
- break;
- }
+static int
+fpxregs_set(struct task_struct *target,
+ const struct utrace_regset *regset,
+ unsigned int pos, unsigned int count,
+ const void *kbuf, const void __user *ubuf)
+{
+ int ret;
- /* when I and D space are separate, this will have to be fixed. */
- case PTRACE_POKETEXT: /* write the word at location addr. */
- case PTRACE_POKEDATA:
- ret = 0;
- if (access_process_vm(child, addr, &data, sizeof(data), 1) == sizeof(data))
- break;
- ret = -EIO;
- break;
+ if (!cpu_has_fxsr)
+ return -ENODEV;
- case PTRACE_POKEUSR: /* write the word at location addr in the USER area */
- ret = -EIO;
- if ((addr & 3) || addr < 0 ||
- addr > sizeof(struct user) - 3)
- break;
+ if (tsk_used_math(target))
+ unlazy_fpu(target);
+ else if (pos == 0 && count == sizeof(target->thread.i387.fxsave))
+ set_stopped_child_used_math(target);
+ else
+ init_fpu(target);
- if (addr < FRAME_SIZE*sizeof(long)) {
- ret = putreg(child, addr, data);
- break;
- }
- /* We need to be very careful here. We implicitly
- want to modify a portion of the task_struct, and we
- have to be selective about what portions we allow someone
- to modify. */
-
- ret = -EIO;
- if(addr >= (long) &dummy->u_debugreg[0] &&
- addr <= (long) &dummy->u_debugreg[7]){
-
- if(addr == (long) &dummy->u_debugreg[4]) break;
- if(addr == (long) &dummy->u_debugreg[5]) break;
- if(addr < (long) &dummy->u_debugreg[4] &&
- ((unsigned long) data) >= TASK_SIZE-3) break;
-
- if(addr == (long) &dummy->u_debugreg[7]) {
- data &= ~DR_CONTROL_RESERVED;
- for(i=0; i<4; i++)
- if ((0x5f54 >> ((data >> (16 + 4*i)) & 0xf)) & 1)
- goto out_tsk;
- }
-
- addr -= (long) &dummy->u_debugreg;
- addr = addr >> 2;
- child->thread.debugreg[addr] = data;
- ret = 0;
- }
- break;
-
- case PTRACE_SYSCALL: /* continue and stop at next (return from) syscall */
- case PTRACE_CONT: { /* restart after signal. */
- long tmp;
-
- ret = -EIO;
- if ((unsigned long) data > _NSIG)
- break;
- if (request == PTRACE_SYSCALL) {
- set_tsk_thread_flag(child, TIF_SYSCALL_TRACE);
+ ret = utrace_regset_copyin(&pos, &count, &kbuf, &ubuf,
+ &target->thread.i387.fxsave, 0, -1);
+
+ updated_fpxregs(target);
+
+ return ret;
+}
+
+
+static int
+dbregs_active(struct task_struct *tsk, const struct utrace_regset *regset)
+{
+ if (tsk->thread.debugreg[DR_CONTROL] | tsk->thread.debugreg[DR_STATUS])
+ return 8;
+ return 0;
+}
+
+static int
+dbregs_get(struct task_struct *target,
+ const struct utrace_regset *regset,
+ unsigned int pos, unsigned int count,
+ void *kbuf, void __user *ubuf)
+{
+ /*
+ * The hardware updates the status register on a debug trap,
+ * but do_debug (traps.c) save it for us when that happens.
+ * So whether the target is current or not, thread.debugreg is good.
+ */
+
+ return utrace_regset_copyout(&pos, &count, &kbuf, &ubuf,
+ target->thread.debugreg, 0, -1);
+}
+
+static int
+dbregs_set(struct task_struct *target,
+ const struct utrace_regset *regset,
+ unsigned int pos, unsigned int count,
+ const void *kbuf, const void __user *ubuf)
+{
+ for (pos >>= 2, count >>= 2; count > 0; --count, ++pos) {
+ unsigned long val;
+ unsigned int i;
+
+ if (kbuf) {
+ val = *(const unsigned long *) kbuf;
+ kbuf += sizeof(unsigned long);
}
else {
- clear_tsk_thread_flag(child, TIF_SYSCALL_TRACE);
+ if (__get_user(val, (unsigned long __user *) ubuf))
+ return -EFAULT;
+ ubuf += sizeof(unsigned long);
+ }
+
+ if (pos < 4) {
+ if (val >= TASK_SIZE - 3)
+ return -EIO;
+ goto set;
}
- child->exit_code = data;
- /* make sure the single step bit is not set. */
- tmp = get_stack_long(child, EFL_OFFSET) & ~TRAP_FLAG;
- put_stack_long(child, EFL_OFFSET,tmp);
- wake_up_process(child);
- ret = 0;
- break;
+ else if (pos < 6) {
+ if (val != 0)
+ return -EIO;
+ continue;
+ }
+ else if (pos < 7)
+ goto set;
+
+ /* Sanity-check data. Take one half-byte at once with
+ * check = (val >> (16 + 4*i)) & 0xf. It contains the
+ * R/Wi and LENi bits; bits 0 and 1 are R/Wi, and bits
+ * 2 and 3 are LENi. Given a list of invalid values,
+ * we do mask |= 1 << invalid_value, so that
+ * (mask >> check) & 1 is a correct test for invalid
+ * values.
+ *
+ * R/Wi contains the type of the breakpoint /
+ * watchpoint, LENi contains the length of the watched
+ * data in the watchpoint case.
+ *
+ * The invalid values are:
+ * - LENi == 0x10 (undefined), so mask |= 0x0f00.
+ * - R/Wi == 0x10 (break on I/O reads or writes), so
+ * mask |= 0x4444.
+ * - R/Wi == 0x00 && LENi != 0x00, so we have mask |=
+ * 0x1110.
+ *
+ * Finally, mask = 0x0f00 | 0x4444 | 0x1110 == 0x5f54.
+ *
+ * See the Intel Manual "System Programming Guide",
+ * 15.2.4
+ *
+ * Note that LENi == 0x10 is defined on x86_64 in long
+ * mode (i.e. even for 32-bit userspace software, but
+ * 64-bit kernel), so the x86_64 mask value is 0x5454.
+ * See the AMD manual no. 24593 (AMD64 System
+ * Programming)*/
+ val &= ~DR_CONTROL_RESERVED;
+ for (i = 0; i < 4; i++)
+ if ((0x5f54 >> ((val >> (16 + 4*i)) & 0xf)) & 1)
+ return -EIO;
+ if (val)
+ set_tsk_thread_flag(target, TIF_DEBUG);
+ else
+ clear_tsk_thread_flag(target, TIF_DEBUG);
+
+set:
+ target->thread.debugreg[pos] = val;
+ if (target == current)
+ switch (pos) {
+#define DBREG(n) case n: set_debugreg(target->thread.debugreg[n], n); break
+ DBREG(0);
+ DBREG(1);
+ DBREG(2);
+ DBREG(3);
+ DBREG(6);
+ DBREG(7);
+#undef DBREG
+ }
}
+ return 0;
+}
+
+
/*
- * make the child exit. Best I can do is send it a sigkill.
- * perhaps it should be put in the status that it wants to
- * exit.
+ * Perform get_thread_area on behalf of the traced child.
*/
- case PTRACE_KILL: {
- long tmp;
+static int
+tls_get(struct task_struct *target,
+ const struct utrace_regset *regset,
+ unsigned int pos, unsigned int count,
+ void *kbuf, void __user *ubuf)
+{
+ struct user_desc info, *ip;
+ const struct desc_struct *desc;
- ret = 0;
- if (child->state == TASK_ZOMBIE) /* already dead */
- break;
- child->exit_code = SIGKILL;
- /* make sure the single step bit is not set. */
- tmp = get_stack_long(child, EFL_OFFSET) & ~TRAP_FLAG;
- put_stack_long(child, EFL_OFFSET, tmp);
- wake_up_process(child);
- break;
- }
+/*
+ * Get the current Thread-Local Storage area:
+ */
- case PTRACE_SINGLESTEP: { /* set the trap flag. */
- long tmp;
+#define GET_BASE(desc) ( \
+ (((desc)->a >> 16) & 0x0000ffff) | \
+ (((desc)->b << 16) & 0x00ff0000) | \
+ ( (desc)->b & 0xff000000) )
- ret = -EIO;
- if ((unsigned long) data > _NSIG)
- break;
- clear_tsk_thread_flag(child, TIF_SYSCALL_TRACE);
- if ((child->ptrace & PT_DTRACE) == 0) {
- /* Spurious delayed TF traps may occur */
- child->ptrace |= PT_DTRACE;
- }
- tmp = get_stack_long(child, EFL_OFFSET) | TRAP_FLAG;
- put_stack_long(child, EFL_OFFSET, tmp);
- child->exit_code = data;
- /* give it a chance to run. */
- wake_up_process(child);
- ret = 0;
- break;
- }
+#define GET_LIMIT(desc) ( \
+ ((desc)->a & 0x0ffff) | \
+ ((desc)->b & 0xf0000) )
- case PTRACE_DETACH:
- /* detach a process that was attached. */
- ret = ptrace_detach(child, data);
- break;
+#define GET_32BIT(desc) (((desc)->b >> 22) & 1)
+#define GET_CONTENTS(desc) (((desc)->b >> 10) & 3)
+#define GET_WRITABLE(desc) (((desc)->b >> 9) & 1)
+#define GET_LIMIT_PAGES(desc) (((desc)->b >> 23) & 1)
+#define GET_PRESENT(desc) (((desc)->b >> 15) & 1)
+#define GET_USEABLE(desc) (((desc)->b >> 20) & 1)
- case PTRACE_GETREGS: { /* Get all gp regs from the child. */
- if (!access_ok(VERIFY_WRITE, datap, FRAME_SIZE*sizeof(long))) {
- ret = -EIO;
- break;
- }
- for ( i = 0; i < FRAME_SIZE*sizeof(long); i += sizeof(long) ) {
- __put_user(getreg(child, i), datap);
- datap++;
+ desc = &target->thread.tls_array[pos / sizeof(struct user_desc)];
+ ip = kbuf ?: &info;
+ memset(ip, 0, sizeof *ip);
+ for (; count > 0; count -= sizeof(struct user_desc), ++desc) {
+ ip->entry_number = (desc - &target->thread.tls_array[0]
+ + GDT_ENTRY_TLS_MIN);
+ ip->base_addr = GET_BASE(desc);
+ ip->limit = GET_LIMIT(desc);
+ ip->seg_32bit = GET_32BIT(desc);
+ ip->contents = GET_CONTENTS(desc);
+ ip->read_exec_only = !GET_WRITABLE(desc);
+ ip->limit_in_pages = GET_LIMIT_PAGES(desc);
+ ip->seg_not_present = !GET_PRESENT(desc);
+ ip->useable = GET_USEABLE(desc);
+
+ if (kbuf)
+ ++ip;
+ else {
+ if (__copy_to_user(ubuf, &info, sizeof(info)))
+ return -EFAULT;
+ ubuf += sizeof(info);
}
- ret = 0;
- break;
}
- case PTRACE_SETREGS: { /* Set all gp regs in the child. */
- unsigned long tmp;
- if (!access_ok(VERIFY_READ, datap, FRAME_SIZE*sizeof(long))) {
- ret = -EIO;
- break;
+ return 0;
+}
+
+/*
+ * Perform set_thread_area on behalf of the traced child.
+ */
+static int
+tls_set(struct task_struct *target,
+ const struct utrace_regset *regset,
+ unsigned int pos, unsigned int count,
+ const void *kbuf, const void __user *ubuf)
+{
+ struct user_desc info;
+ struct desc_struct *desc;
+ struct desc_struct newtls[GDT_ENTRY_TLS_ENTRIES];
+ unsigned int i;
+ int cpu;
+
+ pos /= sizeof(struct user_desc);
+ count /= sizeof(struct user_desc);
+
+ desc = newtls;
+ for (i = 0; i < count; ++i, ++desc) {
+ const struct user_desc *ip;
+ if (kbuf) {
+ ip = kbuf;
+ kbuf += sizeof(struct user_desc);
}
- for ( i = 0; i < FRAME_SIZE*sizeof(long); i += sizeof(long) ) {
- __get_user(tmp, datap);
- putreg(child, i, tmp);
- datap++;
+ else {
+ ip = &info;
+ if (__copy_from_user(&info, ubuf, sizeof(info)))
+ return -EFAULT;
+ ubuf += sizeof(struct user_desc);
}
- ret = 0;
- break;
- }
- case PTRACE_GETFPREGS: { /* Get the child FPU state. */
- if (!access_ok(VERIFY_WRITE, datap,
- sizeof(struct user_i387_struct))) {
- ret = -EIO;
- break;
+ if (LDT_empty(ip)) {
+ desc->a = 0;
+ desc->b = 0;
+ } else {
+ desc->a = LDT_entry_a(ip);
+ desc->b = LDT_entry_b(ip);
}
- ret = 0;
- if (!child->used_math)
- init_fpu(child);
- get_fpregs((struct user_i387_struct __user *)data, child);
- break;
}
- case PTRACE_SETFPREGS: { /* Set the child FPU state. */
- if (!access_ok(VERIFY_READ, datap,
- sizeof(struct user_i387_struct))) {
- ret = -EIO;
- break;
- }
- child->used_math = 1;
- set_fpregs(child, (struct user_i387_struct __user *)data);
- ret = 0;
- break;
- }
+ /*
+ * We must not get preempted while modifying the TLS.
+ */
+ cpu = get_cpu();
+ memcpy(&target->thread.tls_array[pos], newtls,
+ count * sizeof(newtls[0]));
+ if (target == current)
+ load_TLS(&target->thread, cpu);
+ put_cpu();
+
+ return 0;
+}
- case PTRACE_GETFPXREGS: { /* Get the child extended FPU state. */
- if (!access_ok(VERIFY_WRITE, datap,
- sizeof(struct user_fxsr_struct))) {
- ret = -EIO;
- break;
- }
- if (!child->used_math)
- init_fpu(child);
- ret = get_fpxregs((struct user_fxsr_struct __user *)data, child);
- break;
- }
- case PTRACE_SETFPXREGS: { /* Set the child extended FPU state. */
- if (!access_ok(VERIFY_READ, datap,
- sizeof(struct user_fxsr_struct))) {
- ret = -EIO;
+/*
+ * Determine how many TLS slots are in use.
+ */
+static int
+tls_active(struct task_struct *target, const struct utrace_regset *regset)
+{
+ int i;
+ for (i = GDT_ENTRY_TLS_ENTRIES; i > 0; --i) {
+ struct desc_struct *desc = &target->thread.tls_array[i - 1];
+ if ((desc->a | desc->b) != 0)
break;
- }
- child->used_math = 1;
- ret = set_fpxregs(child, (struct user_fxsr_struct __user *)data);
- break;
}
+ return i;
+}
- case PTRACE_GET_THREAD_AREA:
- ret = ptrace_get_thread_area(child, addr,
- (struct user_desc __user *) data);
- break;
+/*
+ * These are our native regset flavors.
+ * XXX ioperm? vm86?
+ */
+static const struct utrace_regset native_regsets[] = {
+ {
+ .n = FRAME_SIZE, .size = sizeof(long), .align = sizeof(long),
+ .get = genregs_get, .set = genregs_set
+ },
+ {
+ .n = sizeof(struct user_i387_struct) / sizeof(long),
+ .size = sizeof(long), .align = sizeof(long),
+ .active = fpregs_active,
+ .get = fpregs_get, .set = fpregs_set
+ },
+ {
+ .n = sizeof(struct user_fxsr_struct) / sizeof(long),
+ .size = sizeof(long), .align = sizeof(long),
+ .active = fpxregs_active,
+ .get = fpxregs_get, .set = fpxregs_set
+ },
+ {
+ .n = GDT_ENTRY_TLS_ENTRIES,
+ .bias = GDT_ENTRY_TLS_MIN,
+ .size = sizeof(struct user_desc),
+ .align = sizeof(struct user_desc),
+ .active = tls_active, .get = tls_get, .set = tls_set
+ },
+ {
+ .n = 8, .size = sizeof(long), .align = sizeof(long),
+ .active = dbregs_active,
+ .get = dbregs_get, .set = dbregs_set
+ },
+};
+
+const struct utrace_regset_view utrace_i386_native = {
+ .name = "i386", .e_machine = EM_386,
+ .regsets = native_regsets, .n = ARRAY_SIZE(native_regsets)
+};
+EXPORT_SYMBOL_GPL(utrace_i386_native);
+
+#ifdef CONFIG_PTRACE
+static const struct ptrace_layout_segment i386_uarea[] = {
+ {0, FRAME_SIZE*4, 0, 0},
+ {FRAME_SIZE*4, offsetof(struct user, u_debugreg[0]), -1, 0},
+ {offsetof(struct user, u_debugreg[0]),
+ offsetof(struct user, u_debugreg[8]), 4, 0},
+ {0, 0, -1, 0}
+};
+
+int arch_ptrace(long *req, struct task_struct *child,
+ struct utrace_attached_engine *engine,
+ unsigned long addr, unsigned long data, long *val)
+{
+ switch (*req) {
+ case PTRACE_PEEKUSR:
+ return ptrace_peekusr(child, engine, i386_uarea, addr, data);
+ case PTRACE_POKEUSR:
+ return ptrace_pokeusr(child, engine, i386_uarea, addr, data);
+ case PTRACE_GETREGS:
+ return ptrace_whole_regset(child, engine, data, 0, 0);
+ case PTRACE_SETREGS:
+ return ptrace_whole_regset(child, engine, data, 0, 1);
+ case PTRACE_GETFPREGS:
+ return ptrace_whole_regset(child, engine, data, 1, 0);
+ case PTRACE_SETFPREGS:
+ return ptrace_whole_regset(child, engine, data, 1, 1);
+ case PTRACE_GETFPXREGS:
+ return ptrace_whole_regset(child, engine, data, 2, 0);
+ case PTRACE_SETFPXREGS:
+ return ptrace_whole_regset(child, engine, data, 2, 1);
+ case PTRACE_GET_THREAD_AREA:
case PTRACE_SET_THREAD_AREA:
- ret = ptrace_set_thread_area(child, addr,
- (struct user_desc __user *) data);
- break;
-
- default:
- ret = ptrace_request(child, request, addr, data);
- break;
+ return ptrace_onereg_access(child, engine,
+ utrace_native_view(current), 3,
+ addr, (void __user *)data,
+ *req == PTRACE_SET_THREAD_AREA);
}
-out_tsk:
- put_task_struct(child);
-out:
- unlock_kernel();
- return ret;
+ return -ENOSYS;
+}
+#endif
+
+void send_sigtrap(struct task_struct *tsk, struct pt_regs *regs, int error_code)
+{
+ struct siginfo info;
+
+ tsk->thread.trap_no = 1;
+ tsk->thread.error_code = error_code;
+
+ memset(&info, 0, sizeof(info));
+ info.si_signo = SIGTRAP;
+ info.si_code = TRAP_BRKPT;
+
+ /* User-mode eip? */
+ info.si_addr = user_mode_vm(regs) ? (void __user *) regs->eip : NULL;
+
+ /* Send us the fakey SIGTRAP */
+ force_sig_info(SIGTRAP, &info, tsk);
}
/* notification of system call entry/exit
__attribute__((regparm(3)))
void do_syscall_trace(struct pt_regs *regs, int entryexit)
{
- if (unlikely(current->audit_context)) {
- if (!entryexit)
- audit_syscall_entry(current, regs->orig_eax,
- regs->ebx, regs->ecx,
- regs->edx, regs->esi);
- else
- audit_syscall_exit(current, regs->eax);
- }
+ /* do the secure computing check first */
+ if (!entryexit)
+ secure_computing(regs->orig_eax);
- if (!test_thread_flag(TIF_SYSCALL_TRACE))
- return;
- if (!(current->ptrace & PT_PTRACED))
- return;
- /* the 0x80 provides a way for the tracing parent to distinguish
- between a syscall stop and SIGTRAP delivery */
- ptrace_notify(SIGTRAP | ((current->ptrace & PT_TRACESYSGOOD)
- ? 0x80 : 0));
+ if (unlikely(current->audit_context) && entryexit)
+ audit_syscall_exit(AUDITSC_RESULT(regs->eax), regs->eax);
- /*
- * this isn't the same as continuing with a signal, but it will do
- * for normal use. strace only continues with a signal if the
- * stopping signal is not SIGTRAP. -brl
- */
- if (current->exit_code) {
- send_sig(current->exit_code, current, 1);
- current->exit_code = 0;
+ if (test_thread_flag(TIF_SYSCALL_TRACE))
+ tracehook_report_syscall(regs, entryexit);
+
+ if (test_thread_flag(TIF_SINGLESTEP) && entryexit) {
+ send_sigtrap(current, regs, 0); /* XXX */
+ tracehook_report_syscall_step(regs);
}
+
+ if (unlikely(current->audit_context) && !entryexit)
+ audit_syscall_entry(AUDIT_ARCH_I386, regs->orig_eax,
+ regs->ebx, regs->ecx, regs->edx, regs->esi);
}