From 7b9f5ceef164a4d8fd6c07b20101af1420d6100c Mon Sep 17 00:00:00 2001 From: Ian Lance Taylor Date: Mon, 14 Nov 2016 23:16:04 +0000 Subject: [PATCH] runtime: don't crash if signal handler info argument is nil Apparently on Solaris 10 a SA_SIGINFO signal handler can be invoked with a nil info argument. I would not have believed it but I've now seen it happen, and the sigaction man page actually says "If the second argument is not equal to NULL, it points to a siginfo_t structure...." So, if that happens, don't crash. Also fix another case where we want to make sure that &T{} does not allocate. Reviewed-on: https://go-review.googlesource.com/33150 From-SVN: r242403 --- gcc/go/gofrontend/MERGE | 2 +- libgo/go/runtime/signal_gccgo.go | 9 ++++++++- libgo/go/runtime/signal_sigtramp.go | 3 ++- libgo/runtime/go-signal.c | 6 +++++- 4 files changed, 16 insertions(+), 4 deletions(-) diff --git a/gcc/go/gofrontend/MERGE b/gcc/go/gofrontend/MERGE index 9634f00a66e..1fe9decbd3d 100644 --- a/gcc/go/gofrontend/MERGE +++ b/gcc/go/gofrontend/MERGE @@ -1,4 +1,4 @@ -3c8d91cff0ad3d233ebd268f88a3749d38a0aac1 +eb716b515356166d3177e6244619be5901f31162 The first line of this file holds the git revision number of the last merge done from the gofrontend repository. diff --git a/libgo/go/runtime/signal_gccgo.go b/libgo/go/runtime/signal_gccgo.go index 0ecafccec4c..321c6197889 100644 --- a/libgo/go/runtime/signal_gccgo.go +++ b/libgo/go/runtime/signal_gccgo.go @@ -47,7 +47,14 @@ type sigctxt struct { ctxt unsafe.Pointer } -func (c *sigctxt) sigcode() uint64 { return uint64(c.info.si_code) } +func (c *sigctxt) sigcode() uint64 { + if c.info == nil { + // This can happen on Solaris 10. We don't know the + // code, just avoid a misleading value. + return _SI_USER + 1 + } + return uint64(c.info.si_code) +} //go:nosplit func sigblock() { diff --git a/libgo/go/runtime/signal_sigtramp.go b/libgo/go/runtime/signal_sigtramp.go index 67b9e670433..667d5feed98 100644 --- a/libgo/go/runtime/signal_sigtramp.go +++ b/libgo/go/runtime/signal_sigtramp.go @@ -29,7 +29,8 @@ func sigtrampgo(sig uint32, info *_siginfo_t, ctx unsafe.Pointer) { // get here anyhow. return } - badsignal(uintptr(sig), &sigctxt{info, ctx}) + c := sigctxt{info, ctx} + badsignal(uintptr(sig), &c) return } diff --git a/libgo/runtime/go-signal.c b/libgo/runtime/go-signal.c index 9ee02a34f8f..b844dc59b7c 100644 --- a/libgo/runtime/go-signal.c +++ b/libgo/runtime/go-signal.c @@ -187,7 +187,11 @@ getSiginfo(siginfo_t *info, void *context __attribute__((unused))) Location loc[1]; int32 n; - ret.sigaddr = (uintptr)(info->si_addr); + if (info == nil) { + ret.sigaddr = 0; + } else { + ret.sigaddr = (uintptr)(info->si_addr); + } ret.sigpc = 0; // There doesn't seem to be a portable way to get the PC. -- 2.30.2