Add gvisor presubmit test

[avagin]

No description provided.

[a-nogikh]

I wonder if we'd better hard-code the gVisor release number to make test results more reproducible.

[avagin]

@a-nogikh I was thinking about that too. I think it is better to start with the latest one and then we will be able to change that in case of any problem. I will introduce the same test in the gvisor presubmit suite, so I don't expect any issues here.

[a-nogikh]

Currently it stumbles on the problem fixed in #4986

2024/07/04 03:43:42 [FATAL] failed to create rpc server: open vmlinux: no such file or directory

Let's wait until #4986 is merged.

[dvyukov]

Currently it stumbles on the problem fixed in #4986

2024/07/04 03:43:42 [FATAL] failed to create rpc server: open vmlinux: no such file or directory

Let's wait until #4986 is merged.

I think it's better to make the test as realistic as possible, or it will miss bugs. syz-ci should provide kernel_obj dir, let's do the same here.

[a-nogikh]

Now the test fails with:

./bin/syz-manager -config /tmp/syzkaller-gvisor-test.kCYdNw/config --mode smoke-test
2024/07/04 14:43:26 serving http on http://:54321
2024/07/04 14:43:26 serving rpc on tcp://38615
2024/07/04 14:43:26 booting test machines...
2024/07/04 14:43:26 wait for the connection from test machine...
2024/07/04 14:43:35 vm-0: crash: FATAL ERROR: Error executing inside namespace: re-executing self: fork/exec /proc/self/exe: operation not permitted
2024/07/04 14:43:35 [FATAL] kernel crashed in smoke testing mode, exiting

[avagin]

Now the test fails with:

./bin/syz-manager -config /tmp/syzkaller-gvisor-test.kCYdNw/config --mode smoke-test
2024/07/04 14:43:26 serving http on http://:54321
2024/07/04 14:43:26 serving rpc on tcp://38615
2024/07/04 14:43:26 booting test machines...
2024/07/04 14:43:26 wait for the connection from test machine...
2024/07/04 14:43:35 vm-0: crash: FATAL ERROR: Error executing inside namespace: re-executing self: fork/exec /proc/self/exe: operation not permitted
2024/07/04 14:43:35 [FATAL] kernel crashed in smoke testing mode, exiting

I fixed the test. I checked it with this patch:

diff --git a/pkg/vminfo/linux.go b/pkg/vminfo/linux.go
index 030b9a038..25e90c377 100644
--- a/pkg/vminfo/linux.go
+++ b/pkg/vminfo/linux.go
@@ -45,6 +45,7 @@ func (linux) machineInfos() []machineInfoFunc {
 }
 
 func (linux) parseModules(files filesystem) ([]*cover.KernelModule, error) {
+       return nil, nil
        var modules []*cover.KernelModule
        re := regexp.MustCompile(`(\w+) ([0-9]+) .*(0[x|X][a-fA-F0-9]+)[^\n]*`)
        modulesText, _ := files.ReadFile("/proc/modules")

[avagin]

I think it's better to make the test as realistic as possible, or it will miss bugs. syz-ci should provide kernel_obj dir, let's do the same here.

@dvyukov Can you be a bit more detailed about this kernel_obj dir? What should it contain?

[dvyukov]

I think it's better to make the test as realistic as possible, or it will miss bugs. syz-ci should provide kernel_obj dir, let's do the same here.

@dvyukov Can you be a bit more detailed about this kernel_obj dir? What should it contain?

Any dir that contains the runsc binary renamed to "vmlinux":
https://github.com/google/syzkaller/blob/master/pkg/build/gvisor.go#L94-L95
Not all code distinguished between real Linux and gVisor, so the binary is renamed to "vmlinux".