X-Git-Url: http://drtracing.org/?a=blobdiff_plain;f=mm%2Fprocess_vm_access.c;h=c20ff48994c29050953c79fcdb0633e690bb653e;hb=8cdb878dcb359fd1137e9abdee9322f5e9bcfdf8;hp=e920aa3ce104c35b902e8412864c78102fa3177e;hpb=fb38f9b8fe98a9c1f6b1e57d1b08b1102b293929;p=deliverable%2Flinux.git

diff --git a/mm/process_vm_access.c b/mm/process_vm_access.c
index e920aa3ce104..c20ff48994c2 100644
--- a/mm/process_vm_access.c
+++ b/mm/process_vm_access.c
@@ -298,23 +298,18 @@ static ssize_t process_vm_rw_core(pid_t pid, const struct iovec *lvec,
 		goto free_proc_pages;
 	}
 
-	task_lock(task);
-	if (__ptrace_may_access(task, PTRACE_MODE_ATTACH)) {
-		task_unlock(task);
-		rc = -EPERM;
-		goto put_task_struct;
-	}
-	mm = task->mm;
-
-	if (!mm || (task->flags & PF_KTHREAD)) {
-		task_unlock(task);
-		rc = -EINVAL;
+	mm = mm_access(task, PTRACE_MODE_ATTACH);
+	if (!mm || IS_ERR(mm)) {
+		rc = IS_ERR(mm) ? PTR_ERR(mm) : -ESRCH;
+		/*
+		 * Explicitly map EACCES to EPERM as EPERM is a more a
+		 * appropriate error code for process_vw_readv/writev
+		 */
+		if (rc == -EACCES)
+			rc = -EPERM;
 		goto put_task_struct;
 	}
 
-	atomic_inc(&mm->mm_users);
-	task_unlock(task);
-
 	for (i = 0; i < riovcnt && iov_l_curr_idx < liovcnt; i++) {
 		rc = process_vm_rw_single_vec(
 			(unsigned long)rvec[i].iov_base, rvec[i].iov_len,