Hello Go Experts,
I am observing system stack corruption when panic() is called from go
function. When panic is called from Test4(), as part of
runtime.systemstack_switch(), the RSP and RBP is set in such a way that it
will corrupt the stack.
Rbp = 0x00007ffdb188bd20===> This should be less than 0x7ffdb188bc50. But
it is set to the value which is already used for CGO calls. So it is making
the system stack to corrupt. When the core file is generated, it makes it
unable to debug from the core file using dlv. Can someone please help on
this issue?
RBP 0x7ffdb188bc50 RA 0x45f3f4 runtime.cgocallback
/home/soomohan/mbalraj/GO/go1.20.2/go/src/runtime/asm_amd64.s 1003
RBP 0x7ffdb188bca0 RA 0x4641bd crosscall2
/home/soomohan/mbalraj/GO/go1.20.2/go/src/runtime/cgo/asm_amd64.s 32
RBP 0x7ffdb188bcd0 RA 0x464386 C.Test4 /tmp/go-build/_cgo_export.c 35
RBP 0x7ffdb188bce0 RA 0x464432 C.test1 /home/soomohan/mbalraj/test/hello.go
10
RBP 0x7ffdb188bd00 RA 0x46444d C.test2 /home/soomohan/mbalraj/test/hello.go
15
RBP 0x7ffdb188bd20 RA 0x464468 C.test3 /home/soomohan/mbalraj/test/hello.go
20
RBP 0x7ffdb188bd50 RA 0x4644a7 C._cgo_78b81bbf688e_Cfunc_test3
/tmp/go-build/cgo-gcc-prolog 51
go version
go version go1.20.2 linux/amd64
//hello.go
package main
/*
#include <stdio.h>
extern void Test4(void);
void test1(void) {
Test4();
}
void test2(void) {
int val = 2;
test1();
}
void test3(void) {
int val = 3;
test2();
}
void test4(void) {
printf("Test4()");
}
*/
import "C"
func Test5() {
C.test4()
}
func main() {
C.test3()
}
//export.go
package main
import "C"
//export Test4
func Test4() {
panic("Panic inside Test4")
//Test5()
}
I have written the following script test.start to debug this issue further
in DLV.
def command_goroutine_start_line(args):
regs = registers().Regs
rip = 0
for reg in regs:
if reg.Name == "Rbp":
rbp = int(reg.Value, 16)
elif reg.Name == "Rip":
rip = int(reg.Value, 16)
da = disassemble(StartPC=rip, EndPC=rip+1).Disassemble
print("RBP 0x%x RIP 0x%x %s %s %s" % (rbp, rip,
da[0].Loc.Function.Name_, da[0].Loc.File, da[0].Loc.Line))
while True:
mem = examine_memory(rbp, 8).Mem
val = 0
for i in range(len(mem)):
val <<= 8
val += mem[len(mem) - i - 1]
prbp = val
mem = examine_memory(rbp + 8, 8).Mem
val = 0
for i in range(len(mem)):
val <<= 8
val += mem[len(mem) - i - 1]
ra = val
da = disassemble(StartPC=ra, EndPC=ra+1).Disassemble
print("RBP 0x%x RA 0x%x %s %s %s" % (prbp, ra,
da[0].Loc.Function.Name_, da[0].Loc.File, da[0].Loc.Line))
if prbp == 0:
break
rbp = prbp
def main():
dlv_command("config alias goroutine_start_line gsl")
(dlv)bt
RBP 0x0 RA 0x45f5e1 runtime.goexit
/home/soomohan/mbalraj/GO/go1.20.2/go/src/runtime/asm_amd64.s 1599
0 0x0000000000433b04 in runtime.addOneOpenDeferFrame.func1
at /home/soomohan/mbalraj/GO/go1.20.2/go/src/runtime/panic.go:646
1 0x000000000045f0c0 in runtime.systemstack_switch
at /home/soomohan/mbalraj/GO/go1.20.2/go/src/runtime/asm_amd64.s:463
2 0x0000000000433a89 in runtime.addOneOpenDeferFrame
at /home/soomohan/mbalraj/GO/go1.20.2/go/src/runtime/panic.go:644
3 0x0000000000434357 in runtime.gopanic
at /home/soomohan/mbalraj/GO/go1.20.2/go/src/runtime/panic.go:886
4 0x00000000004642a7 in main.Test4
at ./export.go:7
5 0x000000000046431c in _cgoexp_78b81bbf688e_Test4
at _cgo_gotypes.go:61
6 0x000000000040535b in runtime.cgocallbackg1
at /home/soomohan/mbalraj/GO/go1.20.2/go/src/runtime/cgocall.go:315
7 0x0000000000405079 in runtime.cgocallbackg
at /home/soomohan/mbalraj/GO/go1.20.2/go/src/runtime/cgocall.go:234
8 0x0000000000461b0f in runtime.cgocallbackg
at <autogenerated>:1
9 0x000000000045f3f4 in runtime.cgocallback
at /home/soomohan/mbalraj/GO/go1.20.2/go/src/runtime/asm_amd64.s:998
10 0x0000000000000001 in ???
at ?:-1
11 0x0000000000464386 in C.Test4
at /tmp/go-build/_cgo_export.c:33
12 0x0000000000464432 in C.test1
at ./hello.go:9
13 0x000000000046444d in C.test2
at ./hello.go:14
14 0x0000000000464468 in C.test3
at ./hello.go:19
15 0x00000000004644a7 in C._cgo_78b81bbf688e_Cfunc_test3
15 0x00000000004644a7 in C._cgo_78b81bbf688e_Cfunc_test3
at /tmp/go-build/cgo-gcc-prolog:49
16 0x000000000045f2e4 in runtime.asmcgocall
at /home/soomohan/mbalraj/GO/go1.20.2/go/src/runtime/asm_amd64.s:848
17 0x000000000046448a in C._cgo_78b81bbf688e_Cfunc_test3
at /tmp/go-build/cgo-gcc-prolog:44
18 0x0000000000404f0a in runtime.cgocall
at /home/soomohan/mbalraj/GO/go1.20.2/go/src/runtime/cgocall.go:167
19 0x0000000000464245 in main._Cfunc_test3
at _cgo_gotypes.go:39
20 0x00000000004642d7 in main.main
at ./hello.go:33
21 0x0000000000437073 in runtime.main
at /home/soomohan/mbalraj/GO/go1.20.2/go/src/runtime/proc.go:250
22 0x000000000045f5e1 in runtime.goexit
at /home/soomohan/mbalraj/GO/go1.20.2/go/src/runtime/asm_amd64.s:1598
(dlv)source test.star
(dlv)gsl
(dlv) gsl
RBP 0xc000048c68 RIP 0x433b04 runtime.addOneOpenDeferFrame.func1
/home/soomohan/mbalraj/GO/go1.20.2/go/src/runtime/panic.go 646
RBP 0xc000048d28 RA 0x434357 runtime.gopanic
/home/soomohan/mbalraj/GO/go1.20.2/go/src/runtime/panic.go 905
RBP 0xc000048d48 RA 0x4642a7 main.Test4
/home/soomohan/mbalraj/test/export.go 7
RBP 0xc000048d58 RA 0x46431c _cgoexp_78b81bbf688e_Test4 _cgo_gotypes.go 62
RBP 0xc000048e18 RA 0x40535b runtime.cgocallbackg1
/home/soomohan/mbalraj/GO/go1.20.2/go/src/runtime/cgocall.go 323
RBP 0xc000048ea8 RA 0x405079 runtime.cgocallbackg
/home/soomohan/mbalraj/GO/go1.20.2/go/src/runtime/cgocall.go 240
RBP 0xc000048ed0 RA 0x461b0f runtime.cgocallbackg <autogenerated> 1
RBP 0x7ffdb188bc50 RA 0x45f3f4 runtime.cgocallback
/home/soomohan/mbalraj/GO/go1.20.2/go/src/runtime/asm_amd64.s 1003
RBP 0x7ffdb188bca0 RA 0x4641bd crosscall2
/home/soomohan/mbalraj/GO/go1.20.2/go/src/runtime/cgo/asm_amd64.s 32
RBP 0x7ffdb188bcd0 RA 0x464386 C.Test4 /tmp/go-build/_cgo_export.c 35
RBP 0x7ffdb188bce0 RA 0x464432 C.test1 /home/soomohan/mbalraj/test/hello.go
10
RBP 0x7ffdb188bd00 RA 0x46444d C.test2 /home/soomohan/mbalraj/test/hello.go
15
RBP 0x7ffdb188bd20 RA 0x464468 C.test3 /home/soomohan/mbalraj/test/hello.go
20
RBP 0x7ffdb188bd50 RA 0x4644a7 C._cgo_78b81bbf688e_Cfunc_test3
/tmp/go-build/cgo-gcc-prolog 51
RBP 0xc000048f38 RA 0x45f2e4 runtime.asmcgocall
/home/soomohan/mbalraj/GO/go1.20.2/go/src/runtime/asm_amd64.s 852
RBP 0xc000048f60 RA 0x464245 main._Cfunc_test3 _cgo_gotypes.go 40
RBP 0xc000048f70 RA 0x4642d7 main.main /home/soomohan/mbalraj/test/hello.go
33
RBP 0xc000048fd0 RA 0x437073 runtime.main
/home/soomohan/mbalraj/GO/go1.20.2/go/src/runtime/proc.go 260
RBP 0x0 RA 0x45f5e1 runtime.goexit
/home/soomohan/mbalraj/GO/go1.20.2/go/src/runtime/asm_amd64.s 1599
(dlv)si
(dlv)bt
0 0x000000000045587f in runtime.gentraceback
at /home/soomohan/mbalraj/GO/go1.20.2/go/src/runtime/traceback.go:32
1 0x000000000045f0c0 in runtime.systemstack_switch
at /home/soomohan/mbalraj/GO/go1.20.2/go/src/runtime/asm_amd64.s:463
2 0x0000000000433a89 in runtime.addOneOpenDeferFrame
at /home/soomohan/mbalraj/GO/go1.20.2/go/src/runtime/panic.go:644
3 0x0000000000434357 in runtime.gopanic
at /home/soomohan/mbalraj/GO/go1.20.2/go/src/runtime/panic.go:886
4 0x00000000004642a7 in main.Test4
at ./export.go:7
5 0x000000000046431c in _cgoexp_78b81bbf688e_Test4
at _cgo_gotypes.go:61
6 0x000000000040535b in runtime.cgocallbackg1
at /home/soomohan/mbalraj/GO/go1.20.2/go/src/runtime/cgocall.go:315
7 0x0000000000405079 in runtime.cgocallbackg
at /home/soomohan/mbalraj/GO/go1.20.2/go/src/runtime/cgocall.go:234
8 0x0000000000461b0f in runtime.cgocallbackg
at <autogenerated>:1
9 0x000000000045f3f4 in runtime.cgocallback
at /home/soomohan/mbalraj/GO/go1.20.2/go/src/runtime/asm_amd64.s:998
10 0x0000000000000001 in ???
at ?:-1
11 0x0000000000464386 in C.Test4
at /tmp/go-build/_cgo_export.c:33
12 0x0000000000464432 in C.test1
at ./hello.go:9
13 0x000000000046444d in C.test2
at ./hello.go:14
14 0x0000000000464468 in C.test3
at ./hello.go:19
15 0x0000000000433b4b in runtime.addOneOpenDeferFrame.func1
15 0x0000000000433b4b in runtime.addOneOpenDeferFrame.func1
at /home/soomohan/mbalraj/GO/go1.20.2/go/src/runtime/panic.go:645
16 0x000000000045f129 in runtime.systemstack
at /home/soomohan/mbalraj/GO/go1.20.2/go/src/runtime/asm_amd64.s:496
17 0x0000000000461da5 in runtime.newproc
at <autogenerated>:1
18 0x00000000004cc720 in ???
at ?:-1
19 0x000000000046431c in _cgoexp_78b81bbf688e_Test4
at _cgo_gotypes.go:61
20 0x000000000040535b in runtime.cgocallbackg1
at /home/soomohan/mbalraj/GO/go1.20.2/go/src/runtime/cgocall.go:315
21 0x0000000000405079 in runtime.cgocallbackg
at /home/soomohan/mbalraj/GO/go1.20.2/go/src/runtime/cgocall.go:234
22 0x0000000000461b0f in runtime.cgocallbackg
at <autogenerated>:1
23 0x000000000045f3f4 in runtime.cgocallback
at /home/soomohan/mbalraj/GO/go1.20.2/go/src/runtime/asm_amd64.s:998
24 0x000000000045f0c0 in runtime.systemstack_switch
at /home/soomohan/mbalraj/GO/go1.20.2/go/src/runtime/asm_amd64.s:463
25 0x0000000000404f0a in runtime.cgocall
at /home/soomohan/mbalraj/GO/go1.20.2/go/src/runtime/cgocall.go:167
26 0x0000000000464245 in main._Cfunc_test3
at _cgo_gotypes.go:39
27 0x00000000004642d7 in main.main
at ./hello.go:33
28 0x0000000000437073 in runtime.main
at /home/soomohan/mbalraj/GO/go1.20.2/go/src/runtime/proc.go:250
29 0x000000000045f5e1 in runtime.goexit
at /home/soomohan/mbalraj/GO/go1.20.2/go/src/runtime/asm_amd64.s:1598
(dlv) regs
(dlv) regs
Rip = 0x000000000045587f
Rsp = 0x00007ffdb188ba08
Rax = 0x000000000040535b
Rbx = 0x000000c000048d68
Rcx = 0x0000000000000000
Rdx = 0x0000000000433b60
Rsi = 0x0000000000000000
Rdi = 0x000000c0000061a0
Rbp = 0x00007ffdb188bd20
R8 = 0x0000000000000000
R9 = 0x000000007fffffff
R10 = 0x00007ffdb188bd80
R11 = 0x0000000000000000
R12 = 0x00007ffdb188ba88
R13 = 0x000000c000048c18
R14 = 0x00000000004cc720
R15 = 0x0000000000000000
Rflags = 0x0000000000000246 [PF ZF IF IOPL=0]
Es = 0x0000000000000000
Cs = 0x0000000000000033
Ss = 0x000000000000002b
Ds = 0x0000000000000000
Fs = 0x0000000000000000
Gs = 0x0000000000000000
Fs_base = 0x000015128ba66740
Gs_base = 0x0000000000000000
Best Regards
Mariappan
--
You received this message because you are subscribed to the Google Groups
"golang-nuts" group.
To unsubscribe from this group and stop receiving emails from it, send an email
to golang-nuts+unsubscr...@googlegroups.com.
To view this discussion on the web visit
https://groups.google.com/d/msgid/golang-nuts/CAKKWi6ROmqEq54dnwJmme6D-AZKWM7cexG1_SPpRpz8YUbnBLw%40mail.gmail.com.
