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| author | Yuichi Nishiwaki <yuichi.nishiwaki@gmail.com> | 2019-09-11 02:26:02 +0000 |
|---|---|---|
| committer | Ian Lance Taylor <iant@golang.org> | 2019-09-11 03:32:35 +0000 |
| commit | 904f046e2ba812e04230c6e5252b3ca87c41e0e1 (patch) | |
| tree | 1fa79400ee7e4c2ef7916bff96f094358ee6bc29 /src/runtime/vdso_linux.go | |
| parent | 8ef6d6a8f24354ef167f9dca54ab64e1ea6579f0 (diff) | |
| download | go-904f046e2ba812e04230c6e5252b3ca87c41e0e1.tar.gz go-904f046e2ba812e04230c6e5252b3ca87c41e0e1.zip | |
runtime: fix crash during VDSO calls on arm
As discussed in #32912, a crash occurs when go runtime calls a VDSO function (say
__vdso_clock_gettime) and a signal arrives to that thread.
Since VDSO functions temporarily destroy the G register (R10),
Go functions asynchronously executed in that thread (i.e. Go's signal
handler) can try to load data from the destroyed G, which causes
segmentation fault.
To fix the issue a guard is inserted in front of sigtrampgo, so that the control escapes from
signal handlers without touching G in case the signal occurred in the VDSO context.
The test case included in the patch is take from discussion in a relevant thread on github:
https://github.com/golang/go/issues/32912#issuecomment-517874531.
This patch not only fixes the issue on AArch64 but also that on 32bit ARM.
Fixes #32912
Change-Id: I657472e54b7aa3c617fabc5019ce63aa4105624a
GitHub-Last-Rev: 28ce42c4a02a060f08c1b0dd1c9a392123fd2ee9
GitHub-Pull-Request: golang/go#34030
Reviewed-on: https://go-review.googlesource.com/c/go/+/192937
Run-TryBot: Ian Lance Taylor <iant@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Ian Lance Taylor <iant@golang.org>
Diffstat (limited to 'src/runtime/vdso_linux.go')
| -rw-r--r-- | src/runtime/vdso_linux.go | 1 |
1 files changed, 1 insertions, 0 deletions
diff --git a/src/runtime/vdso_linux.go b/src/runtime/vdso_linux.go index 71ba4ce416..8518276867 100644 --- a/src/runtime/vdso_linux.go +++ b/src/runtime/vdso_linux.go @@ -281,6 +281,7 @@ func vdsoauxv(tag, val uintptr) { } // vdsoMarker reports whether PC is on the VDSO page. +//go:nosplit func inVDSOPage(pc uintptr) bool { for _, k := range vdsoSymbolKeys { if *k.ptr != 0 { |