diff options
Diffstat (limited to 'sysdeps/unix/sysv/linux/ptsname.c')
| -rw-r--r-- | sysdeps/unix/sysv/linux/ptsname.c | 35 |
1 files changed, 35 insertions, 0 deletions
diff --git a/sysdeps/unix/sysv/linux/ptsname.c b/sysdeps/unix/sysv/linux/ptsname.c index 5852e2b295..10365792dd 100644 --- a/sysdeps/unix/sysv/linux/ptsname.c +++ b/sysdeps/unix/sysv/linux/ptsname.c @@ -29,6 +29,23 @@ #include <stdio-common/_itoa.h> +/* Check if DEV corresponds to a master pseudo terminal device. */ +#define MASTER_P(Dev) \ + (major ((Dev)) == 2 \ + || (major ((Dev)) == 4 && minor ((Dev)) >= 128 && minor ((Dev)) < 192) \ + || (major ((Dev)) >= 128 && major ((Dev)) < 136)) + +/* Check if DEV corresponds to a master pseudo terminal device. */ +#define SLAVE_P(Dev) \ + (major ((Dev)) == 3 \ + || (major ((Dev)) == 4 && minor ((Dev)) >= 192 && minor ((Dev)) < 256) \ + || (major ((Dev)) >= 136 && major ((Dev)) < 144)) + +/* Note that major number 4 corresponds to the old BSD style pseudo + terminal devices. As of Linux 2.1.115 these are no longer + supported. They have been replaced by major numbers 2 (masters) + and 3 (slaves). */ + /* Directory where we can find the slave pty nodes. */ #define _PATH_DEVPTS "/dev/pts/" @@ -107,7 +124,16 @@ __ptsname_r (int fd, char *buf, size_t buflen) if (__fstat (fd, &st) < 0) return errno; + /* Check if FD really is a master pseudo terminal. */ + if (! MASTER_P (st.st_rdev)) + { + __set_errno (ENOTTY); + return ENOTTY; + } + ptyno = minor (st.st_rdev); + /* This is for the old BSD pseudo terminals. As of Linux + 2.1.115 these are no longer supported. */ if (major (st.st_rdev) == 4) ptyno -= 128; @@ -126,6 +152,15 @@ __ptsname_r (int fd, char *buf, size_t buflen) if (__xstat (_STAT_VER, buf, &st) < 0) return errno; + /* Check if the name we're about to return really corresponds to a + slave pseudo terminal. */ + if (! S_ISCHR (st.st_mode) || ! SLAVE_P (st.st_rdev)) + { + /* This really is a configuration problem. */ + __set_errno (ENOTTY); + return ENOTTY; + } + __set_errno (save_errno); return 0; } |