Index: components/nacl/loader/nonsfi/nonsfi_sandbox.cc |
diff --git a/components/nacl/loader/nonsfi/nonsfi_sandbox.cc b/components/nacl/loader/nonsfi/nonsfi_sandbox.cc |
index 260dd7509331d5ecbc5431f6bb24386f8e8c5cd7..a6664a321d87347afb60ace1e692d0ff776aefc2 100644 |
--- a/components/nacl/loader/nonsfi/nonsfi_sandbox.cc |
+++ b/components/nacl/loader/nonsfi/nonsfi_sandbox.cc |
@@ -6,6 +6,7 @@ |
#include <errno.h> |
#include <fcntl.h> |
+#include <linux/futex.h> |
#include <linux/net.h> |
#include <sys/prctl.h> |
#include <sys/ptrace.h> |
@@ -35,6 +36,20 @@ namespace nacl { |
namespace nonsfi { |
namespace { |
+ErrorCode RestrictFutexCommands(SandboxBPF* sb) { |
+ // For now, we allow non-PRIVATE FUTEX_WAIT for lll_wait_tid in |
+ // glibc's pthread_join. |
+ // TODO(hamaji): Disallow FUTEX_WAIT by switching to newlib or |
+ // detaching threads. |
+ return sb->Cond(1, ErrorCode::TP_32BIT, |
+ ErrorCode::OP_EQUAL, FUTEX_WAIT, |
+ ErrorCode(ErrorCode::ERR_ALLOWED), |
+ sb->Cond(1, ErrorCode::TP_32BIT, |
+ ErrorCode::OP_HAS_ALL_BITS, FUTEX_PRIVATE_FLAG, |
+ ErrorCode(ErrorCode::ERR_ALLOWED), |
+ sb->Trap(sandbox::CrashSIGSYS_Handler, NULL))); |
+} |
+ |
ErrorCode RestrictFcntlCommands(SandboxBPF* sb) { |
ErrorCode::ArgType mask_long_type; |
if (sizeof(long) == 8) { |
@@ -226,8 +241,6 @@ ErrorCode NaClNonSfiBPFSandboxPolicy::EvaluateSyscallImpl( |
#elif defined(__x86_64__) |
case __NR_fstat: |
#endif |
- // TODO(hamaji): Allow only FUTEX_PRIVATE_FLAG. |
- case __NR_futex: |
// TODO(hamaji): Remove the need of gettid. Currently, this is |
// called from PlatformThread::CurrentId(). |
case __NR_gettid: |
@@ -263,6 +276,9 @@ ErrorCode NaClNonSfiBPFSandboxPolicy::EvaluateSyscallImpl( |
#endif |
return RestrictFcntlCommands(sb); |
+ case __NR_futex: |
+ return RestrictFutexCommands(sb); |
+ |
#if defined(__x86_64__) |
case __NR_mmap: |
#endif |