1
0
mirror of https://github.com/golang/go synced 2024-11-16 21:24:53 -07:00

internal/bisect: adjust stack PCs relative to Callers[2]

This is necessary to make hashes be consistent across runs,
otherwise ASLR messes up search.

Change-Id: Icf668dfe4c2008709f7767397b6700d0d5439287
Reviewed-on: https://go-review.googlesource.com/c/go/+/493857
Reviewed-by: Bryan Mills <bcmills@google.com>
TryBot-Result: Gopher Robot <gobot@golang.org>
Run-TryBot: David Chase <drchase@google.com>
This commit is contained in:
David Chase 2023-05-09 15:03:48 -04:00
parent fffddce55c
commit 841e99e283

View File

@ -412,11 +412,18 @@ func (m *Matcher) Stack(w Writer) bool {
func (m *Matcher) stack(w Writer) bool {
const maxStack = 16
var stk [maxStack]uintptr
n := runtime.Callers(3, stk[:])
if n == 0 {
n := runtime.Callers(2, stk[:])
// caller #2 is not for printing; need it to normalize PCs if ASLR.
if n <= 1 {
return false
}
base := stk[0]
// normalize PCs
for i := range stk[:n] {
stk[i] -= base
}
h := Hash(stk[:n])
if m.ShouldPrint(h) {
var d *dedup
@ -437,7 +444,11 @@ func (m *Matcher) stack(w Writer) bool {
}
} else {
if !d.seen(h) {
printStack(w, h, stk[:n])
// Restore PCs in stack for printing
for i := range stk[:n] {
stk[i] += base
}
printStack(w, h, stk[1:n])
}
}
}