diff options
author | gVisor bot <gvisor-bot@google.com> | 2020-04-08 01:55:07 +0000 |
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committer | gVisor bot <gvisor-bot@google.com> | 2020-04-08 01:55:07 +0000 |
commit | e949f65eeffe7b679e5bbf3136a3f8e9807fd670 (patch) | |
tree | 63fb8069611eefb1cb854f9b3d7d121469b90c69 /runsc/sandbox | |
parent | e86e426bace1598a0c7be525d3b70ff0502284d8 (diff) | |
parent | 56054fc1fb0b92cb985f96467f9059e202d8095c (diff) |
Merge release-20200323.0-89-g56054fc (automated)
Diffstat (limited to 'runsc/sandbox')
-rw-r--r-- | runsc/sandbox/sandbox.go | 58 |
1 files changed, 56 insertions, 2 deletions
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 +} |