Add new interceptor for getmntinfo(3) from NetBSD

[krytarowski]

Summary

getmntinfo gets information about mounted file systems.

Add a dedicated test for new interceptor.

Based on original work by Yang Zheng.

lib/sanitizer_common/sanitizer_common_interceptors.inc

 #if SANITIZER_NETBSD
 #define clock_getres __clock_getres50
 #define clock_gettime __clock_gettime50
 #define clock_settime __clock_settime50
 #define ctime __ctime50
 #define ctime_r __ctime_r50
 #define devname __devname50
 #define getitimer __getitimer50
+#define getmntinfo __getmntinfo13
 #define getpwent __getpwent50
 #define getpwnam __getpwnam50
 #define getpwnam_r __getpwnam_r50
 #define getpwuid __getpwuid50
 #define getpwuid_r __getpwuid_r50
 #define getutent __getutent50
 #define getutxent __getutxent50
 #define getutxid __getutxid50

 #define INIT_NETENT \
   COMMON_INTERCEPT_FUNCTION(getnetent); \
   COMMON_INTERCEPT_FUNCTION(getnetbyname); \
   COMMON_INTERCEPT_FUNCTION(getnetbyaddr)
 #else
 #define INIT_NETENT
 #endif
 
+#if SANITIZER_INTERCEPT_GETMNTINFO
+INTERCEPTOR(int, getmntinfo, void **mntbufp, int flags) {
+  void *ctx;
+  COMMON_INTERCEPTOR_ENTER(ctx, getmntinfo, mntbufp, flags);
+  int cnt = REAL(getmntinfo)(mntbufp, flags);
+  if (cnt > 0 && mntbufp) {
+    COMMON_INTERCEPTOR_WRITE_RANGE(ctx, mntbufp, sizeof(void *));
+    if (*mntbufp)
+      COMMON_INTERCEPTOR_WRITE_RANGE(ctx, *mntbufp, cnt * struct_statvfs_sz);
+  }
+  return cnt;
+}
+#define INIT_GETMNTINFO COMMON_INTERCEPT_FUNCTION(getmntinfo)
+#else
+#define INIT_GETMNTINFO
+#endif
+
 static void InitializeCommonInterceptors() {
   static u64 metadata_mem[sizeof(MetadataHashMap) / sizeof(u64) + 1];
   interceptor_metadata_map = new((void *)&metadata_mem) MetadataHashMap();
 
   INIT_MMAP;
   INIT_MMAP64;
   INIT_TEXTDOMAIN;
   INIT_STRLEN;
static void InitializeCommonInterceptors() {
   INIT_STRLCPY;
   INIT_DEVNAME;
   INIT_DEVNAME_R;
   INIT_FGETLN;
   INIT_STRMODE;
   INIT_TTYENT;
   INIT_PROTOENT;
   INIT_NETENT;
+  INIT_GETMNTINFO;
 
   INIT___PRINTF_CHK;
 }

lib/sanitizer_common/sanitizer_platform_interceptors.h

 
 #define SANITIZER_INTERCEPT_DEVNAME (SI_NETBSD || SI_OPENBSD || SI_FREEBSD)
 #define SANITIZER_INTERCEPT_DEVNAME_R (SI_NETBSD || SI_FREEBSD)
 #define SANITIZER_INTERCEPT_FGETLN (SI_NETBSD || SI_FREEBSD)
 #define SANITIZER_INTERCEPT_STRMODE (SI_NETBSD || SI_FREEBSD)
 #define SANITIZER_INTERCEPT_TTYENT SI_NETBSD
 #define SANITIZER_INTERCEPT_PROTOENT SI_NETBSD
 #define SANITIZER_INTERCEPT_NETENT SI_NETBSD
+#define SANITIZER_INTERCEPT_GETMNTINFO SI_NETBSD
 
 #endif  // #ifndef SANITIZER_PLATFORM_INTERCEPTORS_H

test/sanitizer_common/TestCases/NetBSD/getmntinfo.cc

+// RUN: %clangxx -O0 -g %s -o %t && %run %t 2>&1 | FileCheck %s
+
+#include <sys/types.h>
+
+#include <sys/statvfs.h>
+
+#include <err.h>
+#include <stdio.h>
+#include <stdlib.h>
+
+int main(void) {
+  printf("getmntinfo\n");
+
+  struct statvfs *fss;
+  int nfss = getmntinfo(&fss, MNT_NOWAIT);
+  if (nfss <= 0)
+    errx(1, "getmntinfo");
+
+  for (int i = 0; i < nfss; i++)
+    printf("%d: %s\n", i, fss[i].f_fstypename);
+
+  // CHECK: getmntinfo
+
+  return 0;
+}