daemon: handle EISDIR error from runtime

Go 1.20 made a change to the behaviour of package "os/exec" which was
not mentioned in the release notes:
https://github.com/golang/go/commit/2b8f21409480931b45c983853a78dc7984ed634e
Attempts to execute a directory now return syscall.EISDIR instead of
syscall.EACCESS. Check for EISDIR errors from the runtime and fudge the
returned error message to maintain compatibility with existing versions
of docker/cli when using a version of runc compiled with Go 1.20+.

Signed-off-by: Cory Snider <csnider@mirantis.com>

daemon/errors.go

@@ -160,6 +160,17 @@ func setExitCodeFromError(setExitCode func(exitStatus), err error) error {
 		return startInvalidConfigError(errDesc)
 	}
 
+	// Go 1.20 changed the error for attempting to execute a directory from
+	// syscall.EACCESS to syscall.EISDIR. Unfortunately docker/cli checks
+	// whether the error message contains syscall.EACCESS.Error() to
+	// determine whether to exit with code 126 or 125, so we have little
+	// choice but to fudge the error string.
+	if contains(errDesc, syscall.EISDIR.Error()) {
+		errDesc += ": " + syscall.EACCES.Error()
+		setExitCode(exitEaccess)
+		return startInvalidConfigError(errDesc)
+	}
+
 	// attempted to mount a file onto a directory, or a directory onto a file, maybe from user specified bind mounts
 	if contains(errDesc, syscall.ENOTDIR.Error()) {
 		errDesc += ": Are you trying to mount a directory onto a file (or vice-versa)? Check if the specified host path exists and is the expected type"