Stowage/go
2
0
Fork 0
mirror of https://github.com/golang/go.git synced 2025-12-08 06:10:04 +00:00
Code Issues Projects Releases Packages Wiki Activity

runtime: adjust gsignal stack to current signal stack

Browse source 
If non-Go code calls sigaltstack before a signal is received, use
sigaltstack to determine the current signal stack and set the gsignal
stack to use it.  This makes the Go runtime more robust in the face of
non-Go code.  We still can't handle a disabled signal stack or a signal
triggered with SA_ONSTACK clear, but we now give clear errors for those
cases.

Fixes #7227.
Update #9896.

Change-Id: Icb1607e01fd6461019b6d77d940e59b3aed4d258
Reviewed-on: https://go-review.googlesource.com/18102
Run-TryBot: Ian Lance Taylor <iant@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Mikio Hara <mikioh.mikioh@gmail.com>
This commit is contained in:
Ian Lance Taylor 2015-12-21 22:27:01 -08:00
parent e4dcf5c8c2
commit f7e51c1320
23 changed files with 420 additions and 328 deletions
Download patch file Download diff file Expand all files Collapse all files

40
src/runtime/signal_openbsd.go
View file

@ -4,6 +4,8 @@
package runtime
import "unsafe"
type sigTabT struct {
flags int32
name string
@ -44,3 +46,41 @@ var sigtable = [...]sigTabT{
/* 31 */ {_SigNotify, "SIGUSR2: user-defined signal 2"},
/* 32 */ {_SigNotify, "SIGTHR: reserved"},
}
//go:nosplit
func sigtrampgo(sig uint32, info *siginfo, ctx unsafe.Pointer) {
if sigfwdgo(sig, info, ctx) {
return
}
g := getg()
if g == nil {
badsignal(uintptr(sig))
return
}
// If some non-Go code called sigaltstack, adjust.
sp := uintptr(unsafe.Pointer(&sig))
if sp < g.m.gsignal.stack.lo || sp >= g.m.gsignal.stack.hi {
var st stackt
sigaltstack(nil, &st)
if st.ss_flags&_SS_DISABLE != 0 {
setg(nil)
cgocallback(unsafe.Pointer(funcPC(noSignalStack)), noescape(unsafe.Pointer(&sig)), unsafe.Sizeof(sig))
}
stsp := uintptr(unsafe.Pointer(st.ss_sp))
if sp < stsp || sp >= stsp+st.ss_size {
setg(nil)
cgocallback(unsafe.Pointer(funcPC(sigNotOnStack)), noescape(unsafe.Pointer(&sig)), unsafe.Sizeof(sig))
}
g.m.gsignal.stack.lo = stsp
g.m.gsignal.stack.hi = stsp + st.ss_size
g.m.gsignal.stackguard0 = stsp + _StackGuard
g.m.gsignal.stackguard1 = stsp + _StackGuard
g.m.gsignal.stackAlloc = st.ss_size
g.m.gsignal.stktopsp = getcallersp(unsafe.Pointer(&sig))
}
setg(g.m.gsignal)
sighandler(sig, info, ctx, g)
setg(g)
}