Split getpwent and fgetgrent functions in interceptors

Summary:
NetBSD does not ship with fgetpwent_r() and fgetgrent_r().
Split their interceptors from getpwent_r() and getgrent_r()
and disable for this OS.

Installation of supernumerary interceptors causes leaking of
errors to dlsym(3)-like operations.

No functional change for other OSes.

Reviewers: vitalybuka, joerg

Reviewed By: vitalybuka

Subscribers: srhines, kubamracek, fedor.sergeev, llvm-commits, #sanitizers, mgorny

Tags: #sanitizers

Differential Revision: https://reviews.llvm.org/D54041

llvm-svn: 346038

2 files changed, 33 insertions, 15 deletions

diff --git a/compiler-rt/lib/sanitizer_common/sanitizer_common_interceptors.inc b/compiler-rt/lib/sanitizer_common/sanitizer_common_interceptors.inc
index 5dbc100149b..af09607744d 100644
--- a/compiler-rt/lib/sanitizer_common/sanitizer_common_interceptors.inc
+++ b/compiler-rt/lib/sanitizer_common/sanitizer_common_interceptors.inc
@@ -2034,36 +2034,51 @@ INTERCEPTOR(int, getpwent_r, __sanitizer_passwd *pwbuf, char *buf,
   if (pwbufp) COMMON_INTERCEPTOR_WRITE_RANGE(ctx, pwbufp, sizeof(*pwbufp));
   return res;
 }
-INTERCEPTOR(int, fgetpwent_r, void *fp, __sanitizer_passwd *pwbuf, char *buf,
-            SIZE_T buflen, __sanitizer_passwd **pwbufp) {
+INTERCEPTOR(int, getgrent_r, __sanitizer_group *pwbuf, char *buf, SIZE_T buflen,
+            __sanitizer_group **pwbufp) {
   void *ctx;
-  COMMON_INTERCEPTOR_ENTER(ctx, fgetpwent_r, fp, pwbuf, buf, buflen, pwbufp);
+  COMMON_INTERCEPTOR_ENTER(ctx, getgrent_r, pwbuf, buf, buflen, pwbufp);
   // FIXME: under ASan the call below may write to freed memory and corrupt
   // its metadata. See
   // https://github.com/google/sanitizers/issues/321.
-  int res = REAL(fgetpwent_r)(fp, pwbuf, buf, buflen, pwbufp);
+  int res = REAL(getgrent_r)(pwbuf, buf, buflen, pwbufp);
   if (!res) {
-    if (pwbufp && *pwbufp) unpoison_passwd(ctx, *pwbufp);
+    if (pwbufp && *pwbufp) unpoison_group(ctx, *pwbufp);
     COMMON_INTERCEPTOR_WRITE_RANGE(ctx, buf, buflen);
   }
   if (pwbufp) COMMON_INTERCEPTOR_WRITE_RANGE(ctx, pwbufp, sizeof(*pwbufp));
   return res;
 }
-INTERCEPTOR(int, getgrent_r, __sanitizer_group *pwbuf, char *buf, SIZE_T buflen,
-            __sanitizer_group **pwbufp) {
+#define INIT_GETPWENT_R                   \
+  COMMON_INTERCEPT_FUNCTION(getpwent_r);  \
+  COMMON_INTERCEPT_FUNCTION(getgrent_r);
+#else
+#define INIT_GETPWENT_R
+#endif
+
+#if SANITIZER_INTERCEPT_FGETPWENT_R
+INTERCEPTOR(int, fgetpwent_r, void *fp, __sanitizer_passwd *pwbuf, char *buf,
+            SIZE_T buflen, __sanitizer_passwd **pwbufp) {
   void *ctx;
-  COMMON_INTERCEPTOR_ENTER(ctx, getgrent_r, pwbuf, buf, buflen, pwbufp);
+  COMMON_INTERCEPTOR_ENTER(ctx, fgetpwent_r, fp, pwbuf, buf, buflen, pwbufp);
   // FIXME: under ASan the call below may write to freed memory and corrupt
   // its metadata. See
   // https://github.com/google/sanitizers/issues/321.
-  int res = REAL(getgrent_r)(pwbuf, buf, buflen, pwbufp);
+  int res = REAL(fgetpwent_r)(fp, pwbuf, buf, buflen, pwbufp);
   if (!res) {
-    if (pwbufp && *pwbufp) unpoison_group(ctx, *pwbufp);
+    if (pwbufp && *pwbufp) unpoison_passwd(ctx, *pwbufp);
     COMMON_INTERCEPTOR_WRITE_RANGE(ctx, buf, buflen);
   }
   if (pwbufp) COMMON_INTERCEPTOR_WRITE_RANGE(ctx, pwbufp, sizeof(*pwbufp));
   return res;
 }
+#define INIT_FGETPWENT_R                  \
+  COMMON_INTERCEPT_FUNCTION(fgetpwent_r);
+#else
+#define INIT_FGETPWENT_R
+#endif
+
+#if SANITIZER_INTERCEPT_FGETGRENT_R
 INTERCEPTOR(int, fgetgrent_r, void *fp, __sanitizer_group *pwbuf, char *buf,
             SIZE_T buflen, __sanitizer_group **pwbufp) {
   void *ctx;
@@ -2079,13 +2094,10 @@ INTERCEPTOR(int, fgetgrent_r, void *fp, __sanitizer_group *pwbuf, char *buf,
   if (pwbufp) COMMON_INTERCEPTOR_WRITE_RANGE(ctx, pwbufp, sizeof(*pwbufp));
   return res;
 }
-#define INIT_GETPWENT_R                   \
-  COMMON_INTERCEPT_FUNCTION(getpwent_r);  \
-  COMMON_INTERCEPT_FUNCTION(fgetpwent_r); \
-  COMMON_INTERCEPT_FUNCTION(getgrent_r);  \
+#define INIT_FGETGRENT_R                  \
   COMMON_INTERCEPT_FUNCTION(fgetgrent_r);
 #else
-#define INIT_GETPWENT_R
+#define INIT_FGETGRENT_R
 #endif
 
 #if SANITIZER_INTERCEPT_SETPWENT
@@ -7301,6 +7313,8 @@ static void InitializeCommonInterceptors() {
   INIT_GETPWENT;
   INIT_FGETPWENT;
   INIT_GETPWENT_R;
+  INIT_FGETPWENT_R;
+  INIT_FGETGRENT_R;
   INIT_SETPWENT;
   INIT_CLOCK_GETTIME;
   INIT_GETITIMER;
diff --git a/compiler-rt/lib/sanitizer_common/sanitizer_platform_interceptors.h b/compiler-rt/lib/sanitizer_common/sanitizer_platform_interceptors.h
index f95539a73c6..c05f35c583b 100644
--- a/compiler-rt/lib/sanitizer_common/sanitizer_platform_interceptors.h
+++ b/compiler-rt/lib/sanitizer_common/sanitizer_platform_interceptors.h
@@ -207,9 +207,13 @@
 #define SANITIZER_INTERCEPT_GETPWENT                                          \
   (SI_FREEBSD || SI_NETBSD || SI_OPENBSD || SI_MAC || SI_LINUX_NOT_ANDROID || \
   SI_SOLARIS)
+#define SANITIZER_INTERCEPT_FGETGRENT_R                                       \
+  (SI_FREEBSD || SI_OPENBSD || SI_LINUX_NOT_ANDROID || SI_SOLARIS)
 #define SANITIZER_INTERCEPT_FGETPWENT SI_LINUX_NOT_ANDROID || SI_SOLARIS
 #define SANITIZER_INTERCEPT_GETPWENT_R \
   (SI_FREEBSD || SI_NETBSD || SI_OPENBSD || SI_LINUX_NOT_ANDROID || SI_SOLARIS)
+#define SANITIZER_INTERCEPT_FGETPWENT_R \
+  (SI_FREEBSD || SI_OPENBSD || SI_LINUX_NOT_ANDROID || SI_SOLARIS)
 #define SANITIZER_INTERCEPT_SETPWENT \
   (SI_MAC || SI_LINUX_NOT_ANDROID || SI_SOLARIS)
 #define SANITIZER_INTERCEPT_CLOCK_GETTIME \