X-Git-Url: https://err.no/cgi-bin/gitweb.cgi?a=blobdiff_plain;f=kernel%2Fptrace.c;h=7c76f2ffaeaad78060cfb3223857a89c7a4ccb8f;hb=41a2d6cfa3f77ec469e7e5f06b4d7ffd031f9c0e;hp=9a111f70145c6673cddf08eeaf2e86da03dff8d8;hpb=b20e481ab595e9667c33e2393bdfe9a31870d11f;p=linux-2.6

diff --git a/kernel/ptrace.c b/kernel/ptrace.c
index 9a111f7014..7c76f2ffae 100644
--- a/kernel/ptrace.c
+++ b/kernel/ptrace.c
@@ -18,6 +18,8 @@
 #include <linux/ptrace.h>
 #include <linux/security.h>
 #include <linux/signal.h>
+#include <linux/audit.h>
+#include <linux/pid_namespace.h>
 
 #include <asm/pgtable.h>
 #include <asm/uaccess.h>
@@ -141,7 +143,7 @@ static int may_attach(struct task_struct *task)
 		return -EPERM;
 	smp_rmb();
 	if (task->mm)
-		dumpable = task->mm->dumpable;
+		dumpable = get_dumpable(task->mm);
 	if (!dumpable && !capable(CAP_SYS_PTRACE))
 		return -EPERM;
 
@@ -160,11 +162,14 @@ int ptrace_may_attach(struct task_struct *task)
 int ptrace_attach(struct task_struct *task)
 {
 	int retval;
+	unsigned long flags;
+
+	audit_ptrace(task);
 
 	retval = -EPERM;
 	if (task->pid <= 1)
 		goto out;
-	if (task->tgid == current->tgid)
+	if (same_thread_group(task, current))
 		goto out;
 
 repeat:
@@ -178,9 +183,7 @@ repeat:
 	 * cpu's that may have task_lock).
 	 */
 	task_lock(task);
-	local_irq_disable();
-	if (!write_trylock(&tasklist_lock)) {
-		local_irq_enable();
+	if (!write_trylock_irqsave(&tasklist_lock, flags)) {
 		task_unlock(task);
 		do {
 			cpu_relax();
@@ -208,7 +211,7 @@ repeat:
 	force_sig_specific(SIGSTOP, task);
 
 bad:
-	write_unlock_irq(&tasklist_lock);
+	write_unlock_irqrestore(&tasklist_lock, flags);
 	task_unlock(task);
 out:
 	return retval;
@@ -231,6 +234,7 @@ int ptrace_detach(struct task_struct *child, unsigned int data)
 
 	/* Architecture-specific hardware disable .. */
 	ptrace_disable(child);
+	clear_tsk_thread_flag(child, TIF_SYSCALL_TRACE);
 
 	write_lock_irq(&tasklist_lock);
 	/* protect against de_thread()->release_task() */
@@ -241,60 +245,6 @@ int ptrace_detach(struct task_struct *child, unsigned int data)
 	return 0;
 }
 
-/*
- * Access another process' address space.
- * Source/target buffer must be kernel space, 
- * Do not walk the page table directly, use get_user_pages
- */
-
-int access_process_vm(struct task_struct *tsk, unsigned long addr, void *buf, int len, int write)
-{
-	struct mm_struct *mm;
-	struct vm_area_struct *vma;
-	struct page *page;
-	void *old_buf = buf;
-
-	mm = get_task_mm(tsk);
-	if (!mm)
-		return 0;
-
-	down_read(&mm->mmap_sem);
-	/* ignore errors, just check how much was sucessfully transfered */
-	while (len) {
-		int bytes, ret, offset;
-		void *maddr;
-
-		ret = get_user_pages(tsk, mm, addr, 1,
-				write, 1, &page, &vma);
-		if (ret <= 0)
-			break;
-
-		bytes = len;
-		offset = addr & (PAGE_SIZE-1);
-		if (bytes > PAGE_SIZE-offset)
-			bytes = PAGE_SIZE-offset;
-
-		maddr = kmap(page);
-		if (write) {
-			copy_to_user_page(vma, page, addr,
-					  maddr + offset, buf, bytes);
-			set_page_dirty_lock(page);
-		} else {
-			copy_from_user_page(vma, page, addr,
-					    buf, maddr + offset, bytes);
-		}
-		kunmap(page);
-		page_cache_release(page);
-		len -= bytes;
-		buf += bytes;
-		addr += bytes;
-	}
-	up_read(&mm->mmap_sem);
-	mmput(mm);
-	
-	return buf - old_buf;
-}
-
 int ptrace_readdata(struct task_struct *tsk, unsigned long src, char __user *dst, int len)
 {
 	int copied = 0;
@@ -437,6 +387,9 @@ int ptrace_request(struct task_struct *child, long request,
 	case PTRACE_SETSIGINFO:
 		ret = ptrace_setsiginfo(child, (siginfo_t __user *) data);
 		break;
+	case PTRACE_DETACH:	 /* detach a process that was attached. */
+		ret = ptrace_detach(child, data);
+		break;
 	default:
 		break;
 	}
@@ -491,15 +444,20 @@ struct task_struct *ptrace_get_task_struct(pid_t pid)
 		return ERR_PTR(-EPERM);
 
 	read_lock(&tasklist_lock);
-	child = find_task_by_pid(pid);
+	child = find_task_by_vpid(pid);
 	if (child)
 		get_task_struct(child);
+
 	read_unlock(&tasklist_lock);
 	if (!child)
 		return ERR_PTR(-ESRCH);
 	return child;
 }
 
+#ifndef arch_ptrace_attach
+#define arch_ptrace_attach(child)	do { } while (0)
+#endif
+
 #ifndef __ARCH_SYS_PTRACE
 asmlinkage long sys_ptrace(long request, long pid, long addr, long data)
 {
@@ -523,6 +481,12 @@ asmlinkage long sys_ptrace(long request, long pid, long addr, long data)
 
 	if (request == PTRACE_ATTACH) {
 		ret = ptrace_attach(child);
+		/*
+		 * Some architectures need to do book-keeping after
+		 * a ptrace attach.
+		 */
+		if (!ret)
+			arch_ptrace_attach(child);
 		goto out_put_task_struct;
 	}
 
@@ -541,3 +505,22 @@ asmlinkage long sys_ptrace(long request, long pid, long addr, long data)
 	return ret;
 }
 #endif /* __ARCH_SYS_PTRACE */
+
+int generic_ptrace_peekdata(struct task_struct *tsk, long addr, long data)
+{
+	unsigned long tmp;
+	int copied;
+
+	copied = access_process_vm(tsk, addr, &tmp, sizeof(tmp), 0);
+	if (copied != sizeof(tmp))
+		return -EIO;
+	return put_user(tmp, (unsigned long __user *)data);
+}
+
+int generic_ptrace_pokedata(struct task_struct *tsk, long addr, long data)
+{
+	int copied;
+
+	copied = access_process_vm(tsk, addr, &data, sizeof(data), 1);
+	return (copied == sizeof(data)) ? 0 : -EIO;
+}