[PATCH] D42050: Intercept tzset in MSan on NetBSD

[Kamil Rytarowski via Phabricator via llvm-commits]

krytarowski created this revision.
krytarowski added reviewers: eugenis, vitalybuka, joerg.
krytarowski added a project: Sanitizers.
Herald added subscribers: kristof.beyls, aemerson.

Handle function renaming tzset -> __tzset50 on NetBSD.

Reset arguments passed to tzset() as it does not accept
input parameters.

The tzset() syscall must be called on NetBSD with
InterceptorScope. Once a user sets timezone (either
by TZ or /etc/localtime symlink), tzset() reloads the
internal data and this reports false-positive alarms.

Other functions (like the localtime() interceptor)
already use InterceptorScope.

Sponsored by <The NetBSD Foundation>


Repository:
  rL LLVM

https://reviews.llvm.org/D42050

Files:
  lib/msan/msan_interceptors.cc


Index: lib/msan/msan_interceptors.cc
===================================================================
--- lib/msan/msan_interceptors.cc
+++ lib/msan/msan_interceptors.cc
@@ -38,6 +38,7 @@
 #define fstat __fstat50
 #define gettimeofday __gettimeofday50
 #define getrusage __getrusage50
+#define tzset __tzset50
 #endif
 
 #include <stdarg.h>
@@ -1137,9 +1138,12 @@
 
 extern char *tzname[2];
 
-INTERCEPTOR(void, tzset, int fake) {
+INTERCEPTOR(void, tzset, void) {
   ENSURE_MSAN_INITED();
-  REAL(tzset)(fake);
+  // Required for NetBSD, as there might be reloaded internal structs and we
+  // don't sanitize them.
+  InterceptorScope interceptor_scope;
+  REAL(tzset)();
   if (tzname[0])
     __msan_unpoison(tzname[0], REAL(strlen)(tzname[0]) + 1);
   if (tzname[1])


-------------- next part --------------
A non-text attachment was scrubbed...
Name: D42050.129807.patch
Type: text/x-patch
Size: 775 bytes
Desc: not available
URL: <http://lists.llvm.org/pipermail/llvm-commits/attachments/20180115/69276dac/attachment.bin>