diff options
Diffstat (limited to 'src/runtime')
| -rw-r--r-- | src/runtime/proc.go | 5 | ||||
| -rw-r--r-- | src/runtime/signal_unix.go | 30 |
2 files changed, 22 insertions, 13 deletions
diff --git a/src/runtime/proc.go b/src/runtime/proc.go index aa44c625c5..d51dcb0d22 100644 --- a/src/runtime/proc.go +++ b/src/runtime/proc.go @@ -1251,6 +1251,11 @@ func mstart() { // Initialize stack bounds from system stack. // Cgo may have left stack size in stack.hi. // minit may update the stack bounds. + // + // Note: these bounds may not be very accurate. + // We set hi to &size, but there are things above + // it. The 1024 is supposed to compensate this, + // but is somewhat arbitrary. size := _g_.stack.hi if size == 0 { size = 8192 * sys.StackGuardMultiplier diff --git a/src/runtime/signal_unix.go b/src/runtime/signal_unix.go index 382ba37a87..3f70707ab4 100644 --- a/src/runtime/signal_unix.go +++ b/src/runtime/signal_unix.go @@ -475,6 +475,14 @@ func adjustSignalStack(sig uint32, mp *m, gsigStack *gsignalStack) bool { return false } + var st stackt + sigaltstack(nil, &st) + stsp := uintptr(unsafe.Pointer(st.ss_sp)) + if st.ss_flags&_SS_DISABLE == 0 && sp >= stsp && sp < stsp+st.ss_size { + setGsignalStack(&st, gsigStack) + return true + } + if sp >= mp.g0.stack.lo && sp < mp.g0.stack.hi { // The signal was delivered on the g0 stack. // This can happen when linked with C code @@ -483,29 +491,25 @@ func adjustSignalStack(sig uint32, mp *m, gsigStack *gsignalStack) bool { // the signal handler directly when C code, // including C code called via cgo, calls a // TSAN-intercepted function such as malloc. + // + // We check this condition last as g0.stack.lo + // may be not very accurate (see mstart). st := stackt{ss_size: mp.g0.stack.hi - mp.g0.stack.lo} setSignalstackSP(&st, mp.g0.stack.lo) setGsignalStack(&st, gsigStack) return true } - var st stackt - sigaltstack(nil, &st) + // sp is not within gsignal stack, g0 stack, or sigaltstack. Bad. + setg(nil) + needm() if st.ss_flags&_SS_DISABLE != 0 { - setg(nil) - needm() noSignalStack(sig) - dropm() - } - stsp := uintptr(unsafe.Pointer(st.ss_sp)) - if sp < stsp || sp >= stsp+st.ss_size { - setg(nil) - needm() + } else { sigNotOnStack(sig) - dropm() } - setGsignalStack(&st, gsigStack) - return true + dropm() + return false } // crashing is the number of m's we have waited for when implementing |