Revert "PR11234: Ensure __get_argv doesn't overflow"

This reverts commit f75409719f120a3dbee66d761cf23a64092d1414.

3 files changed, 11 insertions, 82 deletions

diff --git a/tapset/aux_syscalls.stp b/tapset/aux_syscalls.stp
index 2d0ba210..bab0f640 100644
--- a/tapset/aux_syscalls.stp
+++ b/tapset/aux_syscalls.stp
@@ -401,20 +401,20 @@ function __sem_flags:string(semflg:long)
 /* This function copies an argv from userspace. */
 function __get_argv:string(a:long, first:long)
 %{ /* pure */
-	char __user *__user *argv = (char __user *__user *)(long)THIS->a;
+  	char __user *__user *argv = (char __user *__user *)(long)THIS->a;
 	char __user *vstr;
 	int space, rc, len = MAXSTRINGLEN;
 	char *str = THIS->__retvalue;
 	char buf[80];
 	char *ptr = buf;
 
-
+	
 	if (THIS->first && argv)
 		argv++;
 
-	while (argv != NULL && len) {
+	while (argv != NULL) {
 		if (__stp_get_user (vstr, argv))
-			break;
+      			break;
 
 		if (vstr == NULL)
 			break;
@@ -443,8 +443,8 @@ function __get_argv:string(a:long, first:long)
 			*str++='\"';
 			len--;
 		}
-
-		rc = min(len, (int) strlcpy (str, buf, len));
+	
+		rc = strlcpy (str, buf, len); 
 		str += rc;
 		len -= rc;
 
@@ -455,15 +455,13 @@ function __get_argv:string(a:long, first:long)
 
 		argv++;
 	}
-	if (!len)
-		--str;
 	*str = 0;
 %}
 /* This function copies an argv from userspace. */
 function __get_compat_argv:string(a:long, first:long)
 %{ /* pure */
 #ifdef CONFIG_COMPAT
-	compat_uptr_t __user *__user *argv = (compat_uptr_t __user *__user *)(long)THIS->a;
+  	compat_uptr_t __user *__user *argv = (compat_uptr_t __user *__user *)(long)THIS->a;
 	compat_uptr_t __user *vstr;
 	int space, rc, len = MAXSTRINGLEN;
 	char *str = THIS->__retvalue;
@@ -473,9 +471,9 @@ function __get_compat_argv:string(a:long, first:long)
 	if (THIS->first && argv)
 		argv++;
 
-	while (argv != NULL && len) {
+	while (argv != NULL) {
 		if (__stp_get_user (vstr, argv))
-			break;
+      			break;
 
 		if (vstr == NULL)
 			break;
@@ -504,8 +502,8 @@ function __get_compat_argv:string(a:long, first:long)
 			*str++='\"';
 			len--;
 		}
-
-		rc = min(len, (int) strlcpy (str, buf, len));
+	
+		rc = strlcpy (str, buf, len); 
 		str += rc;
 		len -= rc;
 
@@ -516,8 +514,6 @@ function __get_compat_argv:string(a:long, first:long)
 
 		argv++;
 	}
-	if (!len)
-		--str;
 	*str = 0;
 #endif
 %}
diff --git a/testsuite/systemtap.base/overflow-get_argv.exp b/testsuite/systemtap.base/overflow-get_argv.exp
deleted file mode 100644
index ac7fddc5..00000000
--- a/testsuite/systemtap.base/overflow-get_argv.exp
+++ /dev/null
@@ -1,5 +0,0 @@
-# PR11234: __get_argv can overflow its return buffer
-
-set test "overflow-get_argv"
-
-stap_run $srcdir/$subdir/$test.stp no_load $all_pass_string -g -c "/bin/true /usr/bin/*"
diff --git a/testsuite/systemtap.base/overflow-get_argv.stp b/testsuite/systemtap.base/overflow-get_argv.stp
deleted file mode 100644
index 159ef4a8..00000000
--- a/testsuite/systemtap.base/overflow-get_argv.stp
+++ /dev/null
@@ -1,62 +0,0 @@
-// PR11234: __get_argv can overflow its return buffer
-
-// __get_argv has a signature like this:
-//    struct function___get_argv_locals {
-//      int64_t a;
-//      int64_t first;
-//      string_t __retvalue;
-//    } function___get_argv;
-//
-// These functions are meant to have an overlap such that we can tell if
-// __get_argv overran its __retvalue.
-//
-//      int64_t x;
-//      int64_t y;
-//      string_t z;
-//      string_t __retvalue;
-//
-// NB: __retvalue[0] always gets cleared on call, but the rest should be
-// untouched, so we can use it as a sentinal.
-
-function clear:string(x:long, y:long, z:string) %{
-  memset(THIS->__retvalue, 0, MAXSTRINGLEN);
-%}
-
-function check:string(x:long, y:long, z:string) %{
-  int i, bad = 0;
-  for (i=1; i<MAXSTRINGLEN; ++i)
-    if (THIS->__retvalue[i])
-      ++bad;
-
-  if (bad)
-    snprintf(THIS->__retvalue, MAXSTRINGLEN, "%d non-zero bytes", bad);
-  else
-    strlcpy(THIS->__retvalue, "ok", MAXSTRINGLEN);
-%}
-
-global result = "untested"
-
-probe syscall.execve {
-  if (pid() != target())
-    next
-
-  clear(0, 0, "")
-  foo = __get_argv($argv, 0)
-  result = check(0, 0, "")
-
-  // ensure that foo isn't optimized away
-  if (foo == "foo")
-    next
-}
-
-probe begin {
-  println("systemtap starting probe")
-}
-
-probe end {
-  println("systemtap ending probe")
-  if (result == "ok")
-    println("systemtap test success")
-  else
-    println("systemtap test failure: ", result)
-}