mirror of
https://sourceware.org/git/glibc.git
synced 2024-11-08 22:30:07 +00:00
linux ttyname and ttyname_r: do not return wrong results
If a link (say /proc/self/fd/0) pointing to a device, say /dev/pts/2, in a parent mount namespace is passed to ttyname, and a /dev/pts/2 exists (in a different devpts) in the current namespace, then it returns /dev/pts/2. But /dev/pts/2 is NOT the current tty, it is a different file and device. Detect this case and return ENODEV. Userspace can choose to take this as a hint that the fd points to a tty device but to act on the fd rather than the link. Signed-off-by: Serge Hallyn <serge@hallyn.com> Signed-off-by: Christian Brauner <christian.brauner@ubuntu.com>
This commit is contained in:
parent
345118d7f5
commit
15e9a4f378
12
ChangeLog
12
ChangeLog
@ -1,3 +1,15 @@
|
||||
2017-03-19 Christian Brauner <christian.brauner@ubuntu.com>
|
||||
|
||||
* sysdeps/unix/sysv/linux/ttyname.h: New file.
|
||||
* sysdeps/unix/sysv/linux/ttyname.c: Include "ttyname.h".
|
||||
(ttyname) [!_STATBUF_ST_RDEV]: Make code unconditional.
|
||||
Call is_pty when the link does not exist or does not match, fail
|
||||
with ENODEV when it returns true.
|
||||
* sysdeps/unix/sysv/linux/ttyname_r.c: Include "ttyname.h".
|
||||
(__ttyname_r) [!_STATBUF_ST_RDEV]: Make code unconditional.
|
||||
Call is_pty when the link does not exist or does not match, fail
|
||||
with ENODEV when it returns true.
|
||||
|
||||
2017-03-18 Joseph Myers <joseph@codesourcery.com>
|
||||
|
||||
[BZ #16437]
|
||||
|
@ -28,6 +28,8 @@
|
||||
|
||||
#include <_itoa.h>
|
||||
|
||||
#include "ttyname.h"
|
||||
|
||||
#if 0
|
||||
/* Is this used anywhere? It is not exported. */
|
||||
char *__ttyname;
|
||||
@ -170,12 +172,18 @@ ttyname (int fd)
|
||||
#ifdef _STATBUF_ST_RDEV
|
||||
&& S_ISCHR (st1.st_mode)
|
||||
&& st1.st_rdev == st.st_rdev
|
||||
#else
|
||||
&& st1.st_ino == st.st_ino
|
||||
&& st1.st_dev == st.st_dev
|
||||
#endif
|
||||
)
|
||||
&& st1.st_ino == st.st_ino
|
||||
&& st1.st_dev == st.st_dev)
|
||||
return ttyname_buf;
|
||||
|
||||
/* If the link doesn't exist, then it points to a device in another
|
||||
namespace. */
|
||||
if (is_pty (&st))
|
||||
{
|
||||
__set_errno (ENODEV);
|
||||
return NULL;
|
||||
}
|
||||
}
|
||||
|
||||
if (__xstat64 (_STAT_VER, "/dev/pts", &st1) == 0 && S_ISDIR (st1.st_mode))
|
||||
|
34
sysdeps/unix/sysv/linux/ttyname.h
Normal file
34
sysdeps/unix/sysv/linux/ttyname.h
Normal file
@ -0,0 +1,34 @@
|
||||
/* Copyright (C) 2016-2017 Free Software Foundation, Inc.
|
||||
This file is part of the GNU C Library.
|
||||
|
||||
The GNU C Library is free software; you can redistribute it and/or
|
||||
modify it under the terms of the GNU Lesser General Public License as
|
||||
published by the Free Software Foundation; either version 2.1 of the
|
||||
License, or (at your option) any later version.
|
||||
|
||||
The GNU C Library is distributed in the hope that it will be useful,
|
||||
but WITHOUT ANY WARRANTY; without even the implied warranty of
|
||||
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
|
||||
Lesser General Public License for more details.
|
||||
|
||||
You should have received a copy of the GNU Lesser General Public
|
||||
License along with the GNU C Library; see the file COPYING.LIB. If
|
||||
not, see <http://www.gnu.org/licenses/>. */
|
||||
|
||||
#include <unistd.h>
|
||||
#include <sys/sysmacros.h>
|
||||
#include <sys/types.h>
|
||||
#include <sys/stat.h>
|
||||
|
||||
/* Return true if this is a UNIX98 pty device, as defined in
|
||||
linux/Documentation/devices.txt. */
|
||||
static inline int
|
||||
is_pty (struct stat64 *sb)
|
||||
{
|
||||
#ifdef _STATBUF_ST_RDEV
|
||||
int m = major (sb->st_rdev);
|
||||
return (136 <= m && m <= 143);
|
||||
#else
|
||||
return false;
|
||||
#endif
|
||||
}
|
@ -28,6 +28,8 @@
|
||||
|
||||
#include <_itoa.h>
|
||||
|
||||
#include "ttyname.h"
|
||||
|
||||
static int getttyname_r (char *buf, size_t buflen,
|
||||
dev_t mydev, ino64_t myino, int save,
|
||||
int *dostat) internal_function;
|
||||
@ -152,12 +154,19 @@ __ttyname_r (int fd, char *buf, size_t buflen)
|
||||
#ifdef _STATBUF_ST_RDEV
|
||||
&& S_ISCHR (st1.st_mode)
|
||||
&& st1.st_rdev == st.st_rdev
|
||||
#else
|
||||
&& st1.st_ino == st.st_ino
|
||||
&& st1.st_dev == st.st_dev
|
||||
#endif
|
||||
)
|
||||
&& st1.st_ino == st.st_ino
|
||||
&& st1.st_dev == st.st_dev)
|
||||
return 0;
|
||||
|
||||
/* If the link doesn't exist, then it points to a device in another
|
||||
* namespace.
|
||||
*/
|
||||
if (is_pty (&st))
|
||||
{
|
||||
__set_errno (ENODEV);
|
||||
return ENODEV;
|
||||
}
|
||||
}
|
||||
|
||||
/* Prepare the result buffer. */
|
||||
|
Loading…
Reference in New Issue
Block a user