cmd/link: bss section offset exceeds the end of its segment

[qingyunha]

What version of Go are you using (go version)?

$ go version
go version devel go1.17-ed01ceaf48 Fri Jun 25 21:07:44 2021 +0000 linux/amd64

Does this issue reproduce with the latest release?

yes

What operating system and processor architecture are you using (go env)?

go env Output

$ go env
GO111MODULE=""
GOARCH="amd64"
GOBIN=""
GOCACHE="/home/taoqy/.cache/go-build"
GOENV="/home/taoqy/.config/go/env"
GOEXE=""
GOFLAGS=""
GOHOSTARCH="amd64"
GOHOSTOS="linux"
GOINSECURE=""
GOMODCACHE="/home/taoqy/go/pkg/mod"
GONOPROXY=""
GONOSUMDB=""
GOOS="linux"
GOPATH="/home/taoqy/go"
GOPRIVATE=""
GOPROXY="https://goproxy.io"
GOROOT="/home/taoqy/cc/go"
GOSUMDB="sum.golang.org"
GOTMPDIR=""
GOTOOLDIR="/home/taoqy/cc/go/pkg/tool/linux_amd64"
GOVCS=""
GOVERSION="devel go1.17-ed01ceaf48 Fri Jun 25 21:07:44 2021 +0000"
GCCGO="gccgo"
AR="ar"
CC="gcc"
CXX="g++"
CGO_ENABLED="1"
GOMOD="/dev/null"
CGO_CFLAGS="-g -O2"
CGO_CPPFLAGS=""
CGO_CXXFLAGS="-g -O2"
CGO_FFLAGS="-g -O2"
CGO_LDFLAGS="-g -O2"
PKG_CONFIG="pkg-config"
GOGCCFLAGS="-fPIC -m64 -pthread -fmessage-length=0 -fdebug-prefix-map=/tmp/go-build911632282=/tmp/go-build -gno-record-gcc-switches"

What did you do?

build a simple hello.go and readelf its binary.

readelf Output

$ readelf -lS  /tmp/hello
There are 16 section headers, starting at offset 0x1c8:
Section Headers:

[Nr] Name              Type             Address           Offset

Size              EntSize          Flags  Link  Info  Align

[ 0]                   NULL             0000000000000000  00000000

0000000000000000  0000000000000000           0     0     0

[ 1] .text             PROGBITS         0000000000401000  00001000

000000000007d3c7  0000000000000000  AX       0     0     32

[ 2] .rodata           PROGBITS         000000000047f000  0007f000

0000000000034f0c  0000000000000000   A       0     0     32

[ 3] .shstrtab         STRTAB           0000000000000000  000b3f20

00000000000000b5  0000000000000000           0     0     1

[ 4] .typelink         PROGBITS         00000000004b3fe0  000b3fe0

00000000000004d8  0000000000000000   A       0     0     32

[ 5] .itablink         PROGBITS         00000000004b44c0  000b44c0

0000000000000058  0000000000000000   A       0     0     32

[ 6] .gosymtab         PROGBITS         00000000004b4518  000b4518

0000000000000000  0000000000000000   A       0     0     1

[ 7] .gopclntab        PROGBITS         00000000004b4520  000b4520

0000000000058b00  0000000000000000   A       0     0     32

[ 8] .go.buildinfo     PROGBITS         000000000050e000  0010e000

0000000000000020  0000000000000000  WA       0     0     16

[ 9] .noptrdata        PROGBITS         000000000050e020  0010e020

00000000000105c0  0000000000000000  WA       0     0     32

[10] .data             PROGBITS         000000000051e5e0  0011e5e0

0000000000007810  0000000000000000  WA       0     0     32

[11] .bss              NOBITS           0000000000525e00  00125e00

000000000002ef08  0000000000000000  WA       0     0     32

[12] .noptrbss         NOBITS           0000000000554d20  00154d20

0000000000005360  0000000000000000  WA       0     0     32

[13] .note.go.buildid  NOTE             0000000000400f9c  00000f9c

0000000000000064  0000000000000000   A       0     0     4

[14] .symtab           SYMTAB           0000000000000000  00126000

000000000000c330  0000000000000018          15   120     8

[15] .strtab           STRTAB           0000000000000000  00132330

000000000000afde  0000000000000000           0     0     1

Key to Flags:

W (write), A (alloc), X (execute), M (merge), S (strings), I (info),

L (link order), O (extra OS processing required), G (group), T (TLS),

C (compressed), x (unknown), o (OS specific), E (exclude),

l (large), p (processor specific)
Elf file type is EXEC (Executable file)

Entry point 0x45c320

There are 7 program headers, starting at offset 64
Program Headers:

Type           Offset             VirtAddr           PhysAddr

FileSiz            MemSiz              Flags  Align

PHDR           0x0000000000000040 0x0000000000400040 0x0000000000400040

0x0000000000000188 0x0000000000000188  R      0x1000

NOTE           0x0000000000000f9c 0x0000000000400f9c 0x0000000000400f9c

0x0000000000000064 0x0000000000000064  R      0x4

LOAD           0x0000000000000000 0x0000000000400000 0x0000000000400000

0x000000000007e3c7 0x000000000007e3c7  R E    0x1000

LOAD           0x000000000007f000 0x000000000047f000 0x000000000047f000

0x000000000008e020 0x000000000008e020  R      0x1000

LOAD           0x000000000010e000 0x000000000050e000 0x000000000050e000

0x0000000000017e00 0x000000000004c080  RW     0x1000

GNU_STACK      0x0000000000000000 0x0000000000000000 0x0000000000000000

0x0000000000000000 0x0000000000000000  RW     0x8

LOOS+0x5041580 0x0000000000000000 0x0000000000000000 0x0000000000000000

0x0000000000000000 0x0000000000000000         0x8
Section to Segment mapping:

Segment Sections...

00

01     .note.go.buildid

02     .text .note.go.buildid

03     .rodata .typelink .itablink .gosymtab .gopclntab

04     .go.buildinfo .noptrdata .data .bss .noptrbss

05

06

For example, the .noptrbss section offset is 0x154d20 that is larger than its segment(the fourth segment) end (0x10e000 + 0x17e00)

What did you expect to see?

.bss and .noptrbss both offset at 0x10e000 + 0x17e00

What did you see instead?

.bss and .noptrbss offset exceed 0x10e000 + 0x17e00

[gopherbot]

Change https://golang.org/cl/334232 mentions this issue: cmd/link: make bss section offset at end of its segment