[PATCHv2] ntdll: Avoid truncating a nonzero exit code to zero in unix

14 May 2019

On Windows, the exit codes can use the full 32 bit range, while
on unix, they are truncated to the lowest 8 bits. If the intended
exit code is nonzero, to indicate failure, but the lower 8 bits
are zero (like when winedbg tries to exit with EXCEPTION_WINE_STUB,
80000100), the observed exit code used to be zero, indicating
successful execution.

Signed-off-by: Martin Storsjo <martin(a)martin.st>
---
Moved fixing up of the return code to the caller of signal_exit_process.
---
 dlls/ntdll/loader.c  |  3 +++
 dlls/ntdll/process.c |  7 ++++++-
 dlls/ntdll/thread.c  | 14 ++++++++++++--
 3 files changed, 21 insertions(+), 3 deletions(-)

diff --git a/dlls/ntdll/loader.c b/dlls/ntdll/loader.c
index 994ff6f215..0279c81aa7 100644
--- a/dlls/ntdll/loader.c
+++ b/dlls/ntdll/loader.c
@@ -3264,6 +3264,9 @@ void WINAPI RtlExitUserProcess( DWORD status )
     NtTerminateProcess( 0, status );
     LdrShutdownProcess();
     NtTerminateProcess( GetCurrentProcess(), status );
+    /* Prevent a nonzero exit code to end up truncated to zero in unix. */
+    if (status != 0 && (status & 0xff) == 0)
+        status = 1;
     exit( status );
 }
 
diff --git a/dlls/ntdll/process.c b/dlls/ntdll/process.c
index 573a7a771d..ea3565cb1c 100644
--- a/dlls/ntdll/process.c
+++ b/dlls/ntdll/process.c
@@ -88,7 +88,12 @@ NTSTATUS WINAPI NtTerminateProcess( HANDLE handle, LONG exit_code )
         self = !ret && reply->self;
     }
     SERVER_END_REQ;
-    if (self && handle) _exit( exit_code );
+    if (self && handle) {
+        /* Prevent a nonzero exit code to end up truncated to zero in unix. */
+        if (exit_code != 0 && (exit_code & 0xff) == 0)
+            exit_code = 1;
+        _exit( exit_code );
+    }
     return ret;
 }
 
diff --git a/dlls/ntdll/thread.c b/dlls/ntdll/thread.c
index be4621819b..b17ddda7b6 100644
--- a/dlls/ntdll/thread.c
+++ b/dlls/ntdll/thread.c
@@ -291,7 +291,12 @@ static void free_thread_data( TEB *teb )
 void abort_thread( int status )
 {
     pthread_sigmask( SIG_BLOCK, &server_block_set, NULL );
-    if (interlocked_xchg_add( &nb_threads, -1 ) <= 1) _exit( status );
+    if (interlocked_xchg_add( &nb_threads, -1 ) <= 1) {
+        /* Prevent a nonzero exit code to end up truncated to zero in unix. */
+        if (status != 0 && (status & 0xff) == 0)
+            status = 1;
+        _exit( status );
+    }
     signal_exit_thread( status );
 }
 
@@ -316,6 +321,7 @@ void WINAPI RtlExitUserThread( ULONG status )
 {
     static void *prev_teb;
     TEB *teb;
+    int exit_code;
 
     if (status)  /* send the exit code to the server (0 is already the default) */
     {
@@ -332,7 +338,11 @@ void WINAPI RtlExitUserThread( ULONG status )
     {
         LdrShutdownProcess();
         pthread_sigmask( SIG_BLOCK, &server_block_set, NULL );
-        signal_exit_process( status );
+        exit_code = status;
+        /* Prevent a nonzero exit code to end up truncated to zero in unix. */
+        if (status != 0 && (status & 0xff) == 0)
+            exit_code = 1;
+        signal_exit_process( exit_code );
     }
 
     LdrShutdownThread();
-- 
2.17.1

    

Martin Storsjo

Marvin

Martin Storsjö

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