[Valgrind-developers] [valgrind] Just set filename ARG to handle /proc/self/exe in open, openat and openat2

[Mark W. <ma...@so...>]

https://sourceware.org/cgit/valgrind/commit/?id=769ca880912f26f3b6033bfe08e7417580b02c25

commit 769ca880912f26f3b6033bfe08e7417580b02c25
Author: Mark Wielaard <ma...@kl...>
Date:   Sat Jul 19 22:19:08 2025 +0200

    Just set filename ARG to handle /proc/self/exe in open, openat and openat2
    
    This simplifies the logic a little and makes reasoning about how the
    PRE handler works slightly simpler.

Diff:
---
 coregrind/m_syswrap/syswrap-generic.c | 3 +--
 coregrind/m_syswrap/syswrap-linux.c   | 6 ++----
 2 files changed, 3 insertions(+), 6 deletions(-)

diff --git a/coregrind/m_syswrap/syswrap-generic.c b/coregrind/m_syswrap/syswrap-generic.c
index 280b1ccb6a..7ac86fbbc0 100644
--- a/coregrind/m_syswrap/syswrap-generic.c
+++ b/coregrind/m_syswrap/syswrap-generic.c
@@ -4692,8 +4692,7 @@ PRE(sys_open)
 
    if (proc_self_exe) {
       // do the syscall with VG_(resolved_exename)
-      SET_STATUS_from_SysRes(VG_(do_syscall3)(SYSNO, (Word)VG_(resolved_exename), ARG2, ARG3));
-      return;
+      ARG1 = (Word)VG_(resolved_exename);
    }
 #endif // defined(VGO_linux)
 
diff --git a/coregrind/m_syswrap/syswrap-linux.c b/coregrind/m_syswrap/syswrap-linux.c
index d1cfdad69a..552fceee8d 100644
--- a/coregrind/m_syswrap/syswrap-linux.c
+++ b/coregrind/m_syswrap/syswrap-linux.c
@@ -6094,8 +6094,7 @@ no_client_write:
    if (proc_self_exe) {
 
       // do the syscall with VG_(resolved_exename)
-      SET_STATUS_from_SysRes(VG_(do_syscall4)(SYSNO, ARG1, (Word)VG_(resolved_exename), ARG3, ARG4));
-      return;
+      ARG2 = (Word)VG_(resolved_exename);
    }
 
    /* Otherwise handle normally */
@@ -14095,8 +14094,7 @@ PRE(sys_openat2)
 
    if (proc_self_exe) {
       // do the syscall with VG_(resolved_exename)
-      SET_STATUS_from_SysRes(VG_(do_syscall4)(SYSNO, ARG1, (Word)VG_(resolved_exename), ARG3, ARG4));
-      return;
+      ARG2 = (Word)VG_(resolved_exename);
    }
 
    /* Otherwise handle normally */