From 223481e92743f305ada22689f4ba41b36119d5fc Mon Sep 17 00:00:00 2001 From: Jianfeng Tan Date: Fri, 20 Sep 2019 17:49:18 +0000 Subject: fix set hostname Previously, when we set hostname: $ strace hostname abc ... sethostname("abc", 3) = -1 ENAMETOOLONG (File name too long) ... According to man 2 sethostname: "The len argument specifies the number of bytes in name. (Thus, name does not require a terminating null byte.)" We wrongly use the CopyStringIn() to check terminating zero byte in the implementation of sethostname syscall. To fix this, we use CopyInBytes() instead. Fixes: #861 Reported-by: chenglang.hy Signed-off-by: Jianfeng Tan --- pkg/sentry/syscalls/linux/sys_utsname.go | 6 +++--- 1 file changed, 3 insertions(+), 3 deletions(-) (limited to 'pkg/sentry') diff --git a/pkg/sentry/syscalls/linux/sys_utsname.go b/pkg/sentry/syscalls/linux/sys_utsname.go index 271ace08e..748e8dd8d 100644 --- a/pkg/sentry/syscalls/linux/sys_utsname.go +++ b/pkg/sentry/syscalls/linux/sys_utsname.go @@ -79,11 +79,11 @@ func Sethostname(t *kernel.Task, args arch.SyscallArguments) (uintptr, *kernel.S return 0, nil, syserror.EINVAL } - name, err := t.CopyInString(nameAddr, int(size)) - if err != nil { + name := make([]byte, size) + if _, err := t.CopyInBytes(nameAddr, name); err != nil { return 0, nil, err } - utsns.SetHostName(name) + utsns.SetHostName(string(name)) return 0, nil, nil } -- cgit v1.2.3