From: Alexandru Dutu <alexandru.dutu@amd.com>
Date: Tue, 2 May 2017 17:56:36 +0000 (-0400)
Subject: syscall_emul: Argument retrieval bug fix
X-Git-Tag: v19.0.0.0~2825
X-Git-Url: https://git.libre-soc.org/?a=commitdiff_plain;h=8020c689f9d9c77585ef9c5f8c627f1f2a7368f8;p=gem5.git

syscall_emul: Argument retrieval bug fix

This commit fixes a stack-buffer underflow
by fixing the way the array is indexed.

Change-Id: I44400e2b99a2f8e1f48f673cd110b9dcd6480a72
Reviewed-on: https://gem5-review.googlesource.com/3040
Reviewed-by: Jason Lowe-Power <jason@lowepower.com>
Reviewed-by: Andreas Sandberg <andreas.sandberg@arm.com>
Reviewed-by: Curtis Dunham <curtis.dunham@arm.com>
Maintainer: Brandon Potter <Brandon.Potter@amd.com>
---

diff --git a/src/sim/syscall_desc.cc b/src/sim/syscall_desc.cc
index 13b519081..3696c1719 100644
--- a/src/sim/syscall_desc.cc
+++ b/src/sim/syscall_desc.cc
@@ -54,11 +54,11 @@ SyscallDesc::doSyscall(int callnum, Process *process, ThreadContext *tc,
     /**
      * Step through the first six parameters for the system call and
      * retrieve their values. Note that index is incremented as a
-     * side-effect of the getSyscallArg method which is why the LHS
-     * needs the "-1".
+     * side-effect of the getSyscallArg method.
      */
-    for (int index = 0; index < 6; )
-        arg[index - 1] = process->getSyscallArg(tc, index);
+    int index = 0;
+    for (int i = 0; i < 6; i++)
+        arg[i] = process->getSyscallArg(tc, index);
 
     /**
      * Linux supports up to six system call arguments through registers