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Message-Id: <20071129115912.451D126F8E7@magilla.localdomain>
Date: Thu, 29 Nov 2007 03:59:12 -0800 (PST)
From: Roland McGrath <roland@...hat.com>
To: Andrew Morton <akpm@...ux-foundation.org>,
Linus Torvalds <torvalds@...ux-foundation.org>
Cc: Thomas Gleixner <tglx@...utronix.de>, Ingo Molnar <mingo@...e.hu>,
"H. Peter Anvin" <hpa@...or.com>
Subject: [PATCH x86/mm 02/11] x86: ptrace_32 renamed
This renames ptrace_32.c back to ptrace.c, in preparation
for merging the 32/64 versions of these files.
Signed-off-by: Roland McGrath <roland@...hat.com>
---
arch/x86/kernel/Makefile_32 | 3 +-
arch/x86/kernel/ptrace.c | 484 +++++++++++++++++++++++++++++++++++++++++++
arch/x86/kernel/ptrace_32.c | 484 -------------------------------------------
3 files changed, 486 insertions(+), 485 deletions(-)
diff --git a/arch/x86/kernel/Makefile_32 b/arch/x86/kernel/Makefile_32
index 369b297..8946cc8 100644
--- a/arch/x86/kernel/Makefile_32
+++ b/arch/x86/kernel/Makefile_32
@@ -6,10 +6,11 @@ extra-y := head_32.o init_task.o vmlinux.lds
CPPFLAGS_vmlinux.lds += -Ui386
obj-y := process_32.o signal_32.o entry_32.o traps_32.o irq_32.o \
- ptrace_32.o time_32.o ioport_32.o ldt.o setup_32.o i8259_32.o sys_i386_32.o \
+ time_32.o ioport_32.o ldt.o setup_32.o i8259_32.o sys_i386_32.o \
pci-dma_32.o i386_ksyms_32.o i387_32.o bootflag.o e820_32.o\
quirks.o i8237.o topology.o alternative.o i8253.o tsc_32.o rtc.o
+obj-y += ptrace.o
obj-y += tls.o
obj-y += step.o
obj-$(CONFIG_STACKTRACE) += stacktrace.o
diff --git a/arch/x86/kernel/ptrace.c b/arch/x86/kernel/ptrace.c
new file mode 100644
index 0000000..fed83d0
--- /dev/null
+++ b/arch/x86/kernel/ptrace.c
@@ -0,0 +1,484 @@
+/* By Ross Biro 1/23/92 */
+/*
+ * Pentium III FXSR, SSE support
+ * Gareth Hughes <gareth@...inux.com>, May 2000
+ */
+
+#include <linux/kernel.h>
+#include <linux/sched.h>
+#include <linux/mm.h>
+#include <linux/smp.h>
+#include <linux/errno.h>
+#include <linux/ptrace.h>
+#include <linux/user.h>
+#include <linux/security.h>
+#include <linux/audit.h>
+#include <linux/seccomp.h>
+#include <linux/signal.h>
+
+#include <asm/uaccess.h>
+#include <asm/pgtable.h>
+#include <asm/system.h>
+#include <asm/processor.h>
+#include <asm/i387.h>
+#include <asm/debugreg.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).
+ */
+#define FLAG_MASK 0x00050dd5
+
+static long *pt_regs_access(struct pt_regs *regs, unsigned long regno)
+{
+ BUILD_BUG_ON(offsetof(struct pt_regs, bx) != 0);
+ if (regno > FS)
+ --regno;
+ return ®s->bx + regno;
+}
+
+static int putreg(struct task_struct *child,
+ unsigned long regno, unsigned long value)
+{
+ struct pt_regs *regs = task_pt_regs(child);
+ regno >>= 2;
+ switch (regno) {
+ case GS:
+ if (value && (value & 3) != 3)
+ return -EIO;
+ child->thread.gs = value;
+ if (child == current)
+ /*
+ * The user-mode %gs is not affected by
+ * kernel entry, so we must update the CPU.
+ */
+ loadsegment(gs, value);
+ return 0;
+ case DS:
+ case ES:
+ case FS:
+ if (value && (value & 3) != 3)
+ return -EIO;
+ value &= 0xffff;
+ break;
+ case SS:
+ case CS:
+ if ((value & 3) != 3)
+ return -EIO;
+ value &= 0xffff;
+ break;
+ case EFL:
+ value &= FLAG_MASK;
+ /*
+ * If the user value contains TF, mark that
+ * it was not "us" (the debugger) that set it.
+ * If not, make sure it stays set if we had.
+ */
+ if (value & X86_EFLAGS_TF)
+ clear_tsk_thread_flag(child, TIF_FORCED_TF);
+ else if (test_tsk_thread_flag(child, TIF_FORCED_TF))
+ value |= X86_EFLAGS_TF;
+ value |= regs->flags & ~FLAG_MASK;
+ break;
+ }
+ *pt_regs_access(regs, regno) = value;
+ return 0;
+}
+
+static unsigned long getreg(struct task_struct *child, unsigned long regno)
+{
+ struct pt_regs *regs = task_pt_regs(child);
+ unsigned long retval = ~0UL;
+
+ regno >>= 2;
+ switch (regno) {
+ case EFL:
+ /*
+ * If the debugger set TF, hide it from the readout.
+ */
+ retval = regs->flags;
+ if (test_tsk_thread_flag(child, TIF_FORCED_TF))
+ retval &= ~X86_EFLAGS_TF;
+ break;
+ case GS:
+ retval = child->thread.gs;
+ if (child == current)
+ savesegment(gs, retval);
+ break;
+ case DS:
+ case ES:
+ case FS:
+ case SS:
+ case CS:
+ retval = 0xffff;
+ /* fall through */
+ default:
+ retval &= *pt_regs_access(regs, regno);
+ }
+ return retval;
+}
+
+/*
+ * This function is trivial and will be inlined by the compiler.
+ * Having it separates the implementation details of debug
+ * registers from the interface details of ptrace.
+ */
+static unsigned long ptrace_get_debugreg(struct task_struct *child, int n)
+{
+ switch (n) {
+ case 0: return child->thread.debugreg0;
+ case 1: return child->thread.debugreg1;
+ case 2: return child->thread.debugreg2;
+ case 3: return child->thread.debugreg3;
+ case 6: return child->thread.debugreg6;
+ case 7: return child->thread.debugreg7;
+ }
+ return 0;
+}
+
+static int ptrace_set_debugreg(struct task_struct *child,
+ int n, unsigned long data)
+{
+ int i;
+
+ if (unlikely(n == 4 || n == 5))
+ return -EIO;
+
+ if (n < 4 && unlikely(data >= TASK_SIZE - 3))
+ return -EIO;
+
+ switch (n) {
+ case 0: child->thread.debugreg0 = data; break;
+ case 1: child->thread.debugreg1 = data; break;
+ case 2: child->thread.debugreg2 = data; break;
+ case 3: child->thread.debugreg3 = data; break;
+
+ case 6:
+ child->thread.debugreg6 = data;
+ break;
+
+ case 7:
+ /*
+ * 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)
+ */
+ data &= ~DR_CONTROL_RESERVED;
+ for (i = 0; i < 4; i++)
+ if ((0x5f54 >> ((data >> (16 + 4*i)) & 0xf)) & 1)
+ return -EIO;
+ child->thread.debugreg7 = data;
+ if (data)
+ set_tsk_thread_flag(child, TIF_DEBUG);
+ else
+ clear_tsk_thread_flag(child, TIF_DEBUG);
+ break;
+ }
+
+ return 0;
+}
+
+/*
+ * Called by kernel/ptrace.c when detaching..
+ *
+ * Make sure the single step bit is not set.
+ */
+void ptrace_disable(struct task_struct *child)
+{
+ user_disable_single_step(child);
+ clear_tsk_thread_flag(child, TIF_SYSCALL_EMU);
+}
+
+long arch_ptrace(struct task_struct *child, long request, long addr, long data)
+{
+ struct user * dummy = NULL;
+ int i, ret;
+ unsigned long __user *datap = (unsigned long __user *)data;
+
+ 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:
+ ret = generic_ptrace_peekdata(child, addr, data);
+ break;
+
+ /* read the word at location addr in the USER area. */
+ case PTRACE_PEEKUSR: {
+ unsigned long tmp;
+
+ ret = -EIO;
+ if ((addr & 3) || addr < 0 ||
+ addr > sizeof(struct user) - 3)
+ break;
+
+ 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 = ptrace_get_debugreg(child, addr);
+ }
+ ret = put_user(tmp, datap);
+ break;
+ }
+
+ /* 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 = generic_ptrace_pokedata(child, addr, data);
+ break;
+
+ 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 (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]){
+ addr -= (long) &dummy->u_debugreg;
+ addr = addr >> 2;
+ ret = ptrace_set_debugreg(child, addr, data);
+ }
+ break;
+
+ 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++;
+ }
+ 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;
+ }
+ for ( i = 0; i < FRAME_SIZE*sizeof(long); i += sizeof(long) ) {
+ __get_user(tmp, datap);
+ putreg(child, i, tmp);
+ datap++;
+ }
+ 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;
+ }
+ ret = 0;
+ if (!tsk_used_math(child))
+ 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;
+ }
+ set_stopped_child_used_math(child);
+ set_fpregs(child, (struct user_i387_struct __user *)data);
+ ret = 0;
+ break;
+ }
+
+ case PTRACE_GETFPXREGS: { /* Get the child extended FPU state. */
+ if (!access_ok(VERIFY_WRITE, datap,
+ sizeof(struct user_fxsr_struct))) {
+ ret = -EIO;
+ break;
+ }
+ if (!tsk_used_math(child))
+ 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;
+ break;
+ }
+ set_stopped_child_used_math(child);
+ ret = set_fpxregs(child, (struct user_fxsr_struct __user *)data);
+ break;
+ }
+
+ case PTRACE_GET_THREAD_AREA:
+ if (addr < 0)
+ return -EIO;
+ ret = do_get_thread_area(child, addr,
+ (struct user_desc __user *) data);
+ break;
+
+ case PTRACE_SET_THREAD_AREA:
+ if (addr < 0)
+ return -EIO;
+ ret = do_set_thread_area(child, addr,
+ (struct user_desc __user *) data, 0);
+ break;
+
+ default:
+ ret = ptrace_request(child, request, addr, data);
+ break;
+ }
+
+ return ret;
+}
+
+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 ip? */
+ info.si_addr = user_mode_vm(regs) ? (void __user *) regs->ip : NULL;
+
+ /* Send us the fake SIGTRAP */
+ force_sig_info(SIGTRAP, &info, tsk);
+}
+
+/* notification of system call entry/exit
+ * - triggered by current->work.syscall_trace
+ */
+__attribute__((regparm(3)))
+int do_syscall_trace(struct pt_regs *regs, int entryexit)
+{
+ int is_sysemu = test_thread_flag(TIF_SYSCALL_EMU);
+ /*
+ * With TIF_SYSCALL_EMU set we want to ignore TIF_SINGLESTEP for syscall
+ * interception
+ */
+ int is_singlestep = !is_sysemu && test_thread_flag(TIF_SINGLESTEP);
+ int ret = 0;
+
+ /* do the secure computing check first */
+ if (!entryexit)
+ secure_computing(regs->orig_ax);
+
+ if (unlikely(current->audit_context)) {
+ if (entryexit)
+ audit_syscall_exit(AUDITSC_RESULT(regs->ax),
+ regs->ax);
+ /* Debug traps, when using PTRACE_SINGLESTEP, must be sent only
+ * on the syscall exit path. Normally, when TIF_SYSCALL_AUDIT is
+ * not used, entry.S will call us only on syscall exit, not
+ * entry; so when TIF_SYSCALL_AUDIT is used we must avoid
+ * calling send_sigtrap() on syscall entry.
+ *
+ * Note that when PTRACE_SYSEMU_SINGLESTEP is used,
+ * is_singlestep is false, despite his name, so we will still do
+ * the correct thing.
+ */
+ else if (is_singlestep)
+ goto out;
+ }
+
+ if (!(current->ptrace & PT_PTRACED))
+ goto out;
+
+ /* If a process stops on the 1st tracepoint with SYSCALL_TRACE
+ * and then is resumed with SYSEMU_SINGLESTEP, it will come in
+ * here. We have to check this and return */
+ if (is_sysemu && entryexit)
+ return 0;
+
+ /* Fake a debug trap */
+ if (is_singlestep)
+ send_sigtrap(current, regs, 0);
+
+ if (!test_thread_flag(TIF_SYSCALL_TRACE) && !is_sysemu)
+ goto out;
+
+ /* the 0x80 provides a way for the tracing parent to distinguish
+ between a syscall stop and SIGTRAP delivery */
+ /* Note that the debugger could change the result of test_thread_flag!*/
+ ptrace_notify(SIGTRAP | ((current->ptrace & PT_TRACESYSGOOD) ? 0x80:0));
+
+ /*
+ * 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;
+ }
+ ret = is_sysemu;
+out:
+ if (unlikely(current->audit_context) && !entryexit)
+ audit_syscall_entry(AUDIT_ARCH_I386, regs->orig_ax,
+ regs->bx, regs->cx, regs->dx, regs->si);
+ if (ret == 0)
+ return 0;
+
+ regs->orig_ax = -1; /* force skip of syscall restarting */
+ if (unlikely(current->audit_context))
+ audit_syscall_exit(AUDITSC_RESULT(regs->ax), regs->ax);
+ return 1;
+}
diff --git a/arch/x86/kernel/ptrace_32.c b/arch/x86/kernel/ptrace_32.c
deleted file mode 100644
index fed83d0..0000000
--- a/arch/x86/kernel/ptrace_32.c
+++ /dev/null
@@ -1,484 +0,0 @@
-/* By Ross Biro 1/23/92 */
-/*
- * Pentium III FXSR, SSE support
- * Gareth Hughes <gareth@...inux.com>, May 2000
- */
-
-#include <linux/kernel.h>
-#include <linux/sched.h>
-#include <linux/mm.h>
-#include <linux/smp.h>
-#include <linux/errno.h>
-#include <linux/ptrace.h>
-#include <linux/user.h>
-#include <linux/security.h>
-#include <linux/audit.h>
-#include <linux/seccomp.h>
-#include <linux/signal.h>
-
-#include <asm/uaccess.h>
-#include <asm/pgtable.h>
-#include <asm/system.h>
-#include <asm/processor.h>
-#include <asm/i387.h>
-#include <asm/debugreg.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).
- */
-#define FLAG_MASK 0x00050dd5
-
-static long *pt_regs_access(struct pt_regs *regs, unsigned long regno)
-{
- BUILD_BUG_ON(offsetof(struct pt_regs, bx) != 0);
- if (regno > FS)
- --regno;
- return ®s->bx + regno;
-}
-
-static int putreg(struct task_struct *child,
- unsigned long regno, unsigned long value)
-{
- struct pt_regs *regs = task_pt_regs(child);
- regno >>= 2;
- switch (regno) {
- case GS:
- if (value && (value & 3) != 3)
- return -EIO;
- child->thread.gs = value;
- if (child == current)
- /*
- * The user-mode %gs is not affected by
- * kernel entry, so we must update the CPU.
- */
- loadsegment(gs, value);
- return 0;
- case DS:
- case ES:
- case FS:
- if (value && (value & 3) != 3)
- return -EIO;
- value &= 0xffff;
- break;
- case SS:
- case CS:
- if ((value & 3) != 3)
- return -EIO;
- value &= 0xffff;
- break;
- case EFL:
- value &= FLAG_MASK;
- /*
- * If the user value contains TF, mark that
- * it was not "us" (the debugger) that set it.
- * If not, make sure it stays set if we had.
- */
- if (value & X86_EFLAGS_TF)
- clear_tsk_thread_flag(child, TIF_FORCED_TF);
- else if (test_tsk_thread_flag(child, TIF_FORCED_TF))
- value |= X86_EFLAGS_TF;
- value |= regs->flags & ~FLAG_MASK;
- break;
- }
- *pt_regs_access(regs, regno) = value;
- return 0;
-}
-
-static unsigned long getreg(struct task_struct *child, unsigned long regno)
-{
- struct pt_regs *regs = task_pt_regs(child);
- unsigned long retval = ~0UL;
-
- regno >>= 2;
- switch (regno) {
- case EFL:
- /*
- * If the debugger set TF, hide it from the readout.
- */
- retval = regs->flags;
- if (test_tsk_thread_flag(child, TIF_FORCED_TF))
- retval &= ~X86_EFLAGS_TF;
- break;
- case GS:
- retval = child->thread.gs;
- if (child == current)
- savesegment(gs, retval);
- break;
- case DS:
- case ES:
- case FS:
- case SS:
- case CS:
- retval = 0xffff;
- /* fall through */
- default:
- retval &= *pt_regs_access(regs, regno);
- }
- return retval;
-}
-
-/*
- * This function is trivial and will be inlined by the compiler.
- * Having it separates the implementation details of debug
- * registers from the interface details of ptrace.
- */
-static unsigned long ptrace_get_debugreg(struct task_struct *child, int n)
-{
- switch (n) {
- case 0: return child->thread.debugreg0;
- case 1: return child->thread.debugreg1;
- case 2: return child->thread.debugreg2;
- case 3: return child->thread.debugreg3;
- case 6: return child->thread.debugreg6;
- case 7: return child->thread.debugreg7;
- }
- return 0;
-}
-
-static int ptrace_set_debugreg(struct task_struct *child,
- int n, unsigned long data)
-{
- int i;
-
- if (unlikely(n == 4 || n == 5))
- return -EIO;
-
- if (n < 4 && unlikely(data >= TASK_SIZE - 3))
- return -EIO;
-
- switch (n) {
- case 0: child->thread.debugreg0 = data; break;
- case 1: child->thread.debugreg1 = data; break;
- case 2: child->thread.debugreg2 = data; break;
- case 3: child->thread.debugreg3 = data; break;
-
- case 6:
- child->thread.debugreg6 = data;
- break;
-
- case 7:
- /*
- * 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)
- */
- data &= ~DR_CONTROL_RESERVED;
- for (i = 0; i < 4; i++)
- if ((0x5f54 >> ((data >> (16 + 4*i)) & 0xf)) & 1)
- return -EIO;
- child->thread.debugreg7 = data;
- if (data)
- set_tsk_thread_flag(child, TIF_DEBUG);
- else
- clear_tsk_thread_flag(child, TIF_DEBUG);
- break;
- }
-
- return 0;
-}
-
-/*
- * Called by kernel/ptrace.c when detaching..
- *
- * Make sure the single step bit is not set.
- */
-void ptrace_disable(struct task_struct *child)
-{
- user_disable_single_step(child);
- clear_tsk_thread_flag(child, TIF_SYSCALL_EMU);
-}
-
-long arch_ptrace(struct task_struct *child, long request, long addr, long data)
-{
- struct user * dummy = NULL;
- int i, ret;
- unsigned long __user *datap = (unsigned long __user *)data;
-
- 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:
- ret = generic_ptrace_peekdata(child, addr, data);
- break;
-
- /* read the word at location addr in the USER area. */
- case PTRACE_PEEKUSR: {
- unsigned long tmp;
-
- ret = -EIO;
- if ((addr & 3) || addr < 0 ||
- addr > sizeof(struct user) - 3)
- break;
-
- 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 = ptrace_get_debugreg(child, addr);
- }
- ret = put_user(tmp, datap);
- break;
- }
-
- /* 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 = generic_ptrace_pokedata(child, addr, data);
- break;
-
- 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 (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]){
- addr -= (long) &dummy->u_debugreg;
- addr = addr >> 2;
- ret = ptrace_set_debugreg(child, addr, data);
- }
- break;
-
- 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++;
- }
- 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;
- }
- for ( i = 0; i < FRAME_SIZE*sizeof(long); i += sizeof(long) ) {
- __get_user(tmp, datap);
- putreg(child, i, tmp);
- datap++;
- }
- 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;
- }
- ret = 0;
- if (!tsk_used_math(child))
- 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;
- }
- set_stopped_child_used_math(child);
- set_fpregs(child, (struct user_i387_struct __user *)data);
- ret = 0;
- break;
- }
-
- case PTRACE_GETFPXREGS: { /* Get the child extended FPU state. */
- if (!access_ok(VERIFY_WRITE, datap,
- sizeof(struct user_fxsr_struct))) {
- ret = -EIO;
- break;
- }
- if (!tsk_used_math(child))
- 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;
- break;
- }
- set_stopped_child_used_math(child);
- ret = set_fpxregs(child, (struct user_fxsr_struct __user *)data);
- break;
- }
-
- case PTRACE_GET_THREAD_AREA:
- if (addr < 0)
- return -EIO;
- ret = do_get_thread_area(child, addr,
- (struct user_desc __user *) data);
- break;
-
- case PTRACE_SET_THREAD_AREA:
- if (addr < 0)
- return -EIO;
- ret = do_set_thread_area(child, addr,
- (struct user_desc __user *) data, 0);
- break;
-
- default:
- ret = ptrace_request(child, request, addr, data);
- break;
- }
-
- return ret;
-}
-
-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 ip? */
- info.si_addr = user_mode_vm(regs) ? (void __user *) regs->ip : NULL;
-
- /* Send us the fake SIGTRAP */
- force_sig_info(SIGTRAP, &info, tsk);
-}
-
-/* notification of system call entry/exit
- * - triggered by current->work.syscall_trace
- */
-__attribute__((regparm(3)))
-int do_syscall_trace(struct pt_regs *regs, int entryexit)
-{
- int is_sysemu = test_thread_flag(TIF_SYSCALL_EMU);
- /*
- * With TIF_SYSCALL_EMU set we want to ignore TIF_SINGLESTEP for syscall
- * interception
- */
- int is_singlestep = !is_sysemu && test_thread_flag(TIF_SINGLESTEP);
- int ret = 0;
-
- /* do the secure computing check first */
- if (!entryexit)
- secure_computing(regs->orig_ax);
-
- if (unlikely(current->audit_context)) {
- if (entryexit)
- audit_syscall_exit(AUDITSC_RESULT(regs->ax),
- regs->ax);
- /* Debug traps, when using PTRACE_SINGLESTEP, must be sent only
- * on the syscall exit path. Normally, when TIF_SYSCALL_AUDIT is
- * not used, entry.S will call us only on syscall exit, not
- * entry; so when TIF_SYSCALL_AUDIT is used we must avoid
- * calling send_sigtrap() on syscall entry.
- *
- * Note that when PTRACE_SYSEMU_SINGLESTEP is used,
- * is_singlestep is false, despite his name, so we will still do
- * the correct thing.
- */
- else if (is_singlestep)
- goto out;
- }
-
- if (!(current->ptrace & PT_PTRACED))
- goto out;
-
- /* If a process stops on the 1st tracepoint with SYSCALL_TRACE
- * and then is resumed with SYSEMU_SINGLESTEP, it will come in
- * here. We have to check this and return */
- if (is_sysemu && entryexit)
- return 0;
-
- /* Fake a debug trap */
- if (is_singlestep)
- send_sigtrap(current, regs, 0);
-
- if (!test_thread_flag(TIF_SYSCALL_TRACE) && !is_sysemu)
- goto out;
-
- /* the 0x80 provides a way for the tracing parent to distinguish
- between a syscall stop and SIGTRAP delivery */
- /* Note that the debugger could change the result of test_thread_flag!*/
- ptrace_notify(SIGTRAP | ((current->ptrace & PT_TRACESYSGOOD) ? 0x80:0));
-
- /*
- * 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;
- }
- ret = is_sysemu;
-out:
- if (unlikely(current->audit_context) && !entryexit)
- audit_syscall_entry(AUDIT_ARCH_I386, regs->orig_ax,
- regs->bx, regs->cx, regs->dx, regs->si);
- if (ret == 0)
- return 0;
-
- regs->orig_ax = -1; /* force skip of syscall restarting */
- if (unlikely(current->audit_context))
- audit_syscall_exit(AUDITSC_RESULT(regs->ax), regs->ax);
- return 1;
-}
-
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