diff options
| -rw-r--r-- | runsc/boot/fs.go | 15 | ||||
| -rw-r--r-- | runsc/container/container.go | 4 | ||||
| -rw-r--r-- | runsc/sandbox/sandbox.go | 58 | ||||
| -rw-r--r-- | runsc/specutils/specutils.go | 5 |
4 files changed, 77 insertions, 5 deletions
diff --git a/runsc/boot/fs.go b/runsc/boot/fs.go index 0f62842ea..82cc612d2 100644 --- a/runsc/boot/fs.go +++ b/runsc/boot/fs.go @@ -824,7 +824,20 @@ func (c *containerMounter) mountSubmount(ctx context.Context, conf *Config, mns inode, err := filesystem.Mount(ctx, mountDevice(m), mf, strings.Join(opts, ","), nil) if err != nil { - return fmt.Errorf("creating mount with source %q: %v", m.Source, err) + err := fmt.Errorf("creating mount with source %q: %v", m.Source, err) + // Check to see if this is a common error due to a Linux bug. + // This error is generated here in order to cause it to be + // printed to the user using Docker via 'runsc create' etc. rather + // than simply printed to the logs for the 'runsc boot' command. + // + // We check the error message string rather than type because the + // actual error types (syscall.EIO, syscall.EPIPE) are lost by file system + // implementation (e.g. p9). + // TODO(gvisor.dev/issue/1765): Remove message when bug is resolved. + if strings.Contains(err.Error(), syscall.EIO.Error()) || strings.Contains(err.Error(), syscall.EPIPE.Error()) { + return fmt.Errorf("%v: %s", err, specutils.FaqErrorMsg("memlock", "you may be encountering a Linux kernel bug")) + } + return err } // If there are submounts, we need to overlay the mount on top of a ramfs diff --git a/runsc/container/container.go b/runsc/container/container.go index c9839044c..7233659b1 100644 --- a/runsc/container/container.go +++ b/runsc/container/container.go @@ -1077,9 +1077,9 @@ func (c *Container) adjustGoferOOMScoreAdj() error { // oom_score_adj is set to the lowest oom_score_adj among the containers // running in the sandbox. // -// TODO(gvisor.dev/issue/512): This call could race with other containers being +// TODO(gvisor.dev/issue/238): This call could race with other containers being // created at the same time and end up setting the wrong oom_score_adj to the -// sandbox. +// sandbox. Use rpc client to synchronize. func adjustSandboxOOMScoreAdj(s *sandbox.Sandbox, rootDir string, destroy bool) error { containers, err := loadSandbox(rootDir, s.ID) if err != nil { diff --git a/runsc/sandbox/sandbox.go b/runsc/sandbox/sandbox.go index 3b06da98b..2d464b1bf 100644 --- a/runsc/sandbox/sandbox.go +++ b/runsc/sandbox/sandbox.go @@ -18,10 +18,12 @@ package sandbox import ( "context" "fmt" + "io" "math" "os" "os/exec" "strconv" + "strings" "syscall" "time" @@ -142,7 +144,19 @@ func New(conf *boot.Config, args *Args) (*Sandbox, error) { // Wait until the sandbox has booted. b := make([]byte, 1) if l, err := clientSyncFile.Read(b); err != nil || l != 1 { - return nil, fmt.Errorf("waiting for sandbox to start: %v", err) + err := fmt.Errorf("waiting for sandbox to start: %v", err) + // If the sandbox failed to start, it may be because the binary + // permissions were incorrect. Check the bits and return a more helpful + // error message. + // + // NOTE: The error message is checked because error types are lost over + // rpc calls. + if strings.Contains(err.Error(), io.EOF.Error()) { + if permsErr := checkBinaryPermissions(conf); permsErr != nil { + return nil, fmt.Errorf("%v: %v", err, permsErr) + } + } + return nil, err } c.Release() @@ -706,7 +720,19 @@ func (s *Sandbox) createSandboxProcess(conf *boot.Config, args *Args, startSyncF log.Debugf("Starting sandbox: %s %v", binPath, cmd.Args) log.Debugf("SysProcAttr: %+v", cmd.SysProcAttr) if err := specutils.StartInNS(cmd, nss); err != nil { - return fmt.Errorf("Sandbox: %v", err) + err := fmt.Errorf("starting sandbox: %v", err) + // If the sandbox failed to start, it may be because the binary + // permissions were incorrect. Check the bits and return a more helpful + // error message. + // + // NOTE: The error message is checked because error types are lost over + // rpc calls. + if strings.Contains(err.Error(), syscall.EACCES.Error()) { + if permsErr := checkBinaryPermissions(conf); permsErr != nil { + return fmt.Errorf("%v: %v", err, permsErr) + } + } + return err } s.child = true s.Pid = cmd.Process.Pid @@ -1169,3 +1195,31 @@ func deviceFileForPlatform(name string) (*os.File, error) { } return f, nil } + +// checkBinaryPermissions verifies that the required binary bits are set on +// the runsc executable. +func checkBinaryPermissions(conf *boot.Config) error { + // All platforms need the other exe bit + neededBits := os.FileMode(0001) + if conf.Platform == platforms.Ptrace { + // Ptrace needs the other read bit + neededBits |= os.FileMode(0004) + } + + exePath, err := os.Executable() + if err != nil { + return fmt.Errorf("getting exe path: %v", err) + } + + // Check the permissions of the runsc binary and print an error if it + // doesn't match expectations. + info, err := os.Stat(exePath) + if err != nil { + return fmt.Errorf("stat file: %v", err) + } + + if info.Mode().Perm()&neededBits != neededBits { + return fmt.Errorf(specutils.FaqErrorMsg("runsc-perms", fmt.Sprintf("%s does not have the correct permissions", exePath))) + } + return nil +} diff --git a/runsc/specutils/specutils.go b/runsc/specutils/specutils.go index d3c2e4e78..0f4a9cf6d 100644 --- a/runsc/specutils/specutils.go +++ b/runsc/specutils/specutils.go @@ -528,3 +528,8 @@ func EnvVar(env []string, name string) (string, bool) { } return "", false } + +// FaqErrorMsg returns an error message pointing to the FAQ. +func FaqErrorMsg(anchor, msg string) string { + return fmt.Sprintf("%s; see https://gvisor.dev/faq#%s for more details", msg, anchor) +} |