commit 7d5777ef15136e4e12a27c85d7b06d6806b98e70
author Treehugger Robot <treehugger-gerrit@google.com> Tue Nov 28 19:05:18 2017 +0000
committer Gerrit Code Review <noreply-gerritcodereview@google.com> Tue Nov 28 19:05:18 2017 +0000
tree ebf184715b7b033ecc4713444976a575c59b7cc7
parent 26b80da44a694f068cc13ca58046f6278a363519
parent 9591df5294527616686c9a99f14a5d94572f637c

Merge "Fix vdso system call fallback failures."

libc/bionic/vdso.cpp

diff --git a/libc/bionic/vdso.cpp b/libc/bionic/vdso.cpp
index 8cdb504..969c39f 100644
--- a/libc/bionic/vdso.cpp
+++ b/libc/bionic/vdso.cpp
@@ -26,11 +26,18 @@
 #include <unistd.h>
 #include "private/KernelArgumentBlock.h"
 
+static inline int vdso_return(int result) {
+  if (__predict_true(result == 0)) return 0;
+
+  errno = -result;
+  return -1;
+}
+
 int clock_gettime(int clock_id, timespec* tp) {
   auto vdso_clock_gettime = reinterpret_cast<decltype(&clock_gettime)>(
     __libc_globals->vdso[VDSO_CLOCK_GETTIME].fn);
   if (__predict_true(vdso_clock_gettime)) {
-    return vdso_clock_gettime(clock_id, tp);
+    return vdso_return(vdso_clock_gettime(clock_id, tp));
   }
   return __clock_gettime(clock_id, tp);
 }
@@ -39,17 +46,15 @@
   auto vdso_gettimeofday = reinterpret_cast<decltype(&gettimeofday)>(
     __libc_globals->vdso[VDSO_GETTIMEOFDAY].fn);
   if (__predict_true(vdso_gettimeofday)) {
-    return vdso_gettimeofday(tv, tz);
+    return vdso_return(vdso_gettimeofday(tv, tz));
   }
   return __gettimeofday(tv, tz);
 }
 
 void __libc_init_vdso(libc_globals* globals, KernelArgumentBlock& args) {
   auto&& vdso = globals->vdso;
-  vdso[VDSO_CLOCK_GETTIME] = { VDSO_CLOCK_GETTIME_SYMBOL,
-                               reinterpret_cast<void*>(__clock_gettime) };
-  vdso[VDSO_GETTIMEOFDAY] = { VDSO_GETTIMEOFDAY_SYMBOL,
-                              reinterpret_cast<void*>(__gettimeofday) };
+  vdso[VDSO_CLOCK_GETTIME] = { VDSO_CLOCK_GETTIME_SYMBOL, nullptr };
+  vdso[VDSO_GETTIMEOFDAY] = { VDSO_GETTIMEOFDAY_SYMBOL, nullptr };
 
   // Do we have a vdso?
   uintptr_t vdso_ehdr_addr = args.getauxval(AT_SYSINFO_EHDR);