X-Git-Url: http://git.onelab.eu/?a=blobdiff_plain;f=arch%2Fx86_64%2Fkernel%2Fptrace.c;h=2d50024c9f308b8fb5f390fb46e88d33bc843d3d;hb=43bc926fffd92024b46cafaf7350d669ba9ca884;hp=fb883d3451e18c0f0057316a61b6228e995be4ee;hpb=cee37fe97739d85991964371c1f3a745c00dd236;p=linux-2.6.git

diff --git a/arch/x86_64/kernel/ptrace.c b/arch/x86_64/kernel/ptrace.c
index fb883d345..2d50024c9 100644
--- a/arch/x86_64/kernel/ptrace.c
+++ b/arch/x86_64/kernel/ptrace.c
@@ -36,9 +36,12 @@
  * in exit.c or in signal.c.
  */
 
-/* determines which flags the user has access to. */
-/* 1 = access 0 = no access */
-#define FLAG_MASK 0x44dd5UL
+/*
+ * Determines which flags the user has access to [1 = access, 0 = no access].
+ * Prohibits changing ID(21), VIP(20), VIF(19), VM(17), IOPL(12-13), IF(9).
+ * Also masks reserved bits (63-22, 15, 5, 3, 1).
+ */
+#define FLAG_MASK 0x54dd5UL
 
 /* set's the trap flag. */
 #define TRAP_FLAG 0x100UL
@@ -64,12 +67,6 @@ static inline unsigned long get_stack_long(struct task_struct *task, int offset)
 	return (*((unsigned long *)stack));
 }
 
-static inline struct pt_regs *get_child_regs(struct task_struct *task)
-{
-	struct pt_regs *regs = (void *)task->thread.rsp0;
-	return regs - 1;
-}
-
 /*
  * 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.  
@@ -167,7 +164,7 @@ static int is_at_popf(struct task_struct *child, struct pt_regs *regs)
 
 static void set_singlestep(struct task_struct *child)
 {
-	struct pt_regs *regs = get_child_regs(child);
+	struct pt_regs *regs = task_pt_regs(child);
 
 	/*
 	 * Always set TIF_SINGLESTEP - this guarantees that
@@ -205,7 +202,7 @@ static void clear_singlestep(struct task_struct *child)
 
 	/* But touch TF only if it was set by us.. */
 	if (child->ptrace & PT_DTRACE) {
-		struct pt_regs *regs = get_child_regs(child);
+		struct pt_regs *regs = task_pt_regs(child);
 		regs->eflags &= ~TRAP_FLAG;
 		child->ptrace &= ~PT_DTRACE;
 	}
@@ -257,12 +254,12 @@ static int putreg(struct task_struct *child,
 			value &= 0xffff;
 			return 0;
 		case offsetof(struct user_regs_struct,fs_base):
-			if (value >= TASK_SIZE)
+			if (value >= TASK_SIZE_OF(child))
 				return -EIO;
 			child->thread.fs = value;
 			return 0;
 		case offsetof(struct user_regs_struct,gs_base):
-			if (value >= TASK_SIZE)
+			if (value >= TASK_SIZE_OF(child))
 				return -EIO;
 			child->thread.gs = value;
 			return 0;
@@ -277,11 +274,6 @@ static int putreg(struct task_struct *child,
 				return -EIO;
 			value &= 0xffff;
 			break;
-		case offsetof(struct user_regs_struct, rip):
-			/* Check if the new RIP address is canonical */
-			if (value >= TASK_SIZE)
-				return -EIO;
-			break;
 	}
 	put_stack_long(child, regno - sizeof(struct pt_regs), value);
 	return 0;
@@ -313,50 +305,11 @@ static unsigned long getreg(struct task_struct *child, unsigned long regno)
 
 }
 
-asmlinkage long sys_ptrace(long request, long pid, unsigned long addr, long data)
+long arch_ptrace(struct task_struct *child, long request, long addr, long data)
 {
-	struct task_struct *child;
 	long i, ret;
 	unsigned ui;
 
-	/* This lock_kernel fixes a subtle race with suid exec */
-	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);
-		if (ret)
-			goto out;
-		/* set the ptrace bit in the process flags. */
-		current->ptrace |= PT_PTRACED;
-		ret = 0;
-		goto out;
-	}
-	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;
-	if (!vx_check(vx_task_xid(child), VX_WATCH|VX_IDENT))
-		goto out_tsk;
-
-	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;
-	}
-	ret = ptrace_check_attach(child, request == PTRACE_KILL); 
-	if (ret < 0) 
-		goto out_tsk;
-
 	switch (request) {
 	/* when I and D space are separate, these will need to be fixed. */
 	case PTRACE_PEEKTEXT: /* read word at location addr. */ 
@@ -421,6 +374,8 @@ asmlinkage long sys_ptrace(long request, long pid, unsigned long addr, long data
 		break;
 
 	case PTRACE_POKEUSR: /* write the word at location addr in the USER area */
+	{
+		int dsize = test_tsk_thread_flag(child, TIF_IA32) ? 3 : 7;
 		ret = -EIO;
 		if ((addr & 7) ||
 		    addr > sizeof(struct user) - 7)
@@ -432,22 +387,22 @@ asmlinkage long sys_ptrace(long request, long pid, unsigned long addr, long data
 			break;
 		/* Disallows to set a breakpoint into the vsyscall */
 		case offsetof(struct user, u_debugreg[0]):
-			if (data >= TASK_SIZE-7) break;
+			if (data >= TASK_SIZE_OF(child) - dsize) break;
 			child->thread.debugreg0 = data;
 			ret = 0;
 			break;
 		case offsetof(struct user, u_debugreg[1]):
-			if (data >= TASK_SIZE-7) break;
+			if (data >= TASK_SIZE_OF(child) - dsize) break;
 			child->thread.debugreg1 = data;
 			ret = 0;
 			break;
 		case offsetof(struct user, u_debugreg[2]):
-			if (data >= TASK_SIZE-7) break;
+			if (data >= TASK_SIZE_OF(child) - dsize) break;
 			child->thread.debugreg2 = data;
 			ret = 0;
 			break;
 		case offsetof(struct user, u_debugreg[3]):
-			if (data >= TASK_SIZE-7) break;
+			if (data >= TASK_SIZE_OF(child) - dsize) break;
 			child->thread.debugreg3 = data;
 			ret = 0;
 			break;
@@ -460,9 +415,9 @@ asmlinkage long sys_ptrace(long request, long pid, unsigned long addr, long data
 		case offsetof(struct user, u_debugreg[7]):
 			/* See arch/i386/kernel/ptrace.c for an explanation of
 			 * this awkward check.*/
-				  data &= ~DR_CONTROL_RESERVED;
-				  for(i=0; i<4; i++)
-					  if ((0x5454 >> ((data >> (16 + 4*i)) & 0xf)) & 1)
+			data &= ~DR_CONTROL_RESERVED;
+			for(i=0; i<4; i++)
+				if ((0x5554 >> ((data >> (16 + 4*i)) & 0xf)) & 1)
 					break;
 			if (i == 4) {
 				child->thread.debugreg7 = data;
@@ -471,6 +426,7 @@ asmlinkage long sys_ptrace(long request, long pid, unsigned long addr, long data
 		  break;
 		}
 		break;
+	}
 	case PTRACE_SYSCALL: /* continue and stop at next (return from) syscall */
 	case PTRACE_CONT:    /* restart after signal. */
 
@@ -607,10 +563,6 @@ asmlinkage long sys_ptrace(long request, long pid, unsigned long addr, long data
 		ret = ptrace_request(child, request, addr, data);
 		break;
 	}
-out_tsk:
-	put_task_struct(child);
-out:
-	unlock_kernel();
 	return ret;
 }
 
@@ -648,12 +600,12 @@ asmlinkage void syscall_trace_enter(struct pt_regs *regs)
 
 	if (unlikely(current->audit_context)) {
 		if (test_thread_flag(TIF_IA32)) {
-			audit_syscall_entry(current, AUDIT_ARCH_I386,
+			audit_syscall_entry(AUDIT_ARCH_I386,
 					    regs->orig_rax,
 					    regs->rbx, regs->rcx,
 					    regs->rdx, regs->rsi);
 		} else {
-			audit_syscall_entry(current, AUDIT_ARCH_X86_64,
+			audit_syscall_entry(AUDIT_ARCH_X86_64,
 					    regs->orig_rax,
 					    regs->rdi, regs->rsi,
 					    regs->rdx, regs->r10);
@@ -664,7 +616,7 @@ asmlinkage void syscall_trace_enter(struct pt_regs *regs)
 asmlinkage void syscall_trace_leave(struct pt_regs *regs)
 {
 	if (unlikely(current->audit_context))
-		audit_syscall_exit(current, AUDITSC_RESULT(regs->rax), regs->rax);
+		audit_syscall_exit(AUDITSC_RESULT(regs->rax), regs->rax);
 
 	if ((test_thread_flag(TIF_SYSCALL_TRACE)
 	     || test_thread_flag(TIF_SINGLESTEP))