[PATCH 02/50] move compat handling of tty ioctls to tty_compat_ioctl()

From: Al Viro
Date: Wed Sep 12 2018 - 22:44:41 EST


From: Al Viro <viro@xxxxxxxxxxxxxxxxxx>

ioctls that are
* callable only via tty_ioctl()
* not driver-specific
* not demand data structure conversions
* either always need passing arg as is or always demand compat_ptr()
get intercepted in tty_compat_ioctl() from the very beginning and
redirecter to tty_ioctl(). As the result, their entries in fs/compat_ioctl.c
(some of those had been missing, BTW) got removed, as well as
n_tty_compat_ioctl_helper() (now it's never called with any cmd it would accept).

Signed-off-by: Al Viro <viro@xxxxxxxxxxxxxxxxxx>
---
drivers/tty/tty_io.c | 77 +++++++++++++++++++++++++++++++++++++++++++++++--
drivers/tty/tty_ioctl.c | 16 ----------
fs/compat_ioctl.c | 51 --------------------------------
include/linux/tty.h | 2 --
4 files changed, 75 insertions(+), 71 deletions(-)

diff --git a/drivers/tty/tty_io.c b/drivers/tty/tty_io.c
index 32bc3e3fe4d3..c2168b43df0f 100644
--- a/drivers/tty/tty_io.c
+++ b/drivers/tty/tty_io.c
@@ -2668,6 +2668,81 @@ static long tty_compat_ioctl(struct file *file, unsigned int cmd,
struct tty_ldisc *ld;
int retval = -ENOIOCTLCMD;

+ switch (cmd) {
+ case TIOCSTI:
+ case TIOCGWINSZ:
+ case TIOCSWINSZ:
+ case TIOCGEXCL:
+ case TIOCGETD:
+ case TIOCSETD:
+ case TIOCGDEV:
+ case TIOCMGET:
+ case TIOCMSET:
+ case TIOCMBIC:
+ case TIOCMBIS:
+ case TIOCGICOUNT:
+ case TIOCGPGRP:
+ case TIOCSPGRP:
+ case TIOCGSID:
+ case TIOCSERGETLSR:
+ case TIOCGRS485:
+ case TIOCSRS485:
+#ifdef TIOCGETP
+ case TIOCGETP:
+ case TIOCSETP:
+ case TIOCSETN:
+#endif
+#ifdef TIOCGETC
+ case TIOCGETC:
+ case TIOCSETC:
+#endif
+#ifdef TIOCGLTC
+ case TIOCGLTC:
+ case TIOCSLTC:
+#endif
+ case TCSETSF:
+ case TCSETSW:
+ case TCSETS:
+ case TCGETS:
+#ifdef TCGETS2
+ case TCGETS2:
+ case TCSETSF2:
+ case TCSETSW2:
+ case TCSETS2:
+#endif
+ case TCGETA:
+ case TCSETAF:
+ case TCSETAW:
+ case TCSETA:
+ case TIOCGLCKTRMIOS:
+ case TIOCSLCKTRMIOS:
+#ifdef TCGETX
+ case TCGETX:
+ case TCSETX:
+ case TCSETXW:
+ case TCSETXF:
+#endif
+ case TIOCGSOFTCAR:
+ case TIOCSSOFTCAR:
+ return tty_ioctl(file, cmd, (unsigned long)compat_ptr(arg));
+ case TIOCCONS:
+ case TIOCEXCL:
+ case TIOCNXCL:
+ case TIOCVHANGUP:
+ case TIOCSBRK:
+ case TIOCCBRK:
+ case TCSBRK:
+ case TCSBRKP:
+ case TCFLSH:
+ case TIOCGPTPEER:
+ case TIOCNOTTY:
+ case TIOCSCTTY:
+ case TCXONC:
+ case TIOCMIWAIT:
+ case TIOCSERCONFIG:
+ return tty_ioctl(file, cmd, arg);
+ }
+
if (tty_paranoia_check(tty, file_inode(file), "tty_ioctl"))
return -EINVAL;

@@ -2682,8 +2757,6 @@ static long tty_compat_ioctl(struct file *file, unsigned int cmd,
return hung_up_tty_compat_ioctl(file, cmd, arg);
if (ld->ops->compat_ioctl)
retval = ld->ops->compat_ioctl(tty, file, cmd, arg);
- else
- retval = n_tty_compat_ioctl_helper(tty, file, cmd, arg);
tty_ldisc_deref(ld);

return retval;
diff --git a/drivers/tty/tty_ioctl.c b/drivers/tty/tty_ioctl.c
index d99fec44036c..9245fffdbceb 100644
--- a/drivers/tty/tty_ioctl.c
+++ b/drivers/tty/tty_ioctl.c
@@ -941,19 +941,3 @@ int n_tty_ioctl_helper(struct tty_struct *tty, struct file *file,
}
}
EXPORT_SYMBOL(n_tty_ioctl_helper);
-
-#ifdef CONFIG_COMPAT
-long n_tty_compat_ioctl_helper(struct tty_struct *tty, struct file *file,
- unsigned int cmd, unsigned long arg)
-{
- switch (cmd) {
- case TIOCGLCKTRMIOS:
- case TIOCSLCKTRMIOS:
- return tty_mode_ioctl(tty, file, cmd, (unsigned long) compat_ptr(arg));
- default:
- return -ENOIOCTLCMD;
- }
-}
-EXPORT_SYMBOL(n_tty_compat_ioctl_helper);
-#endif
-
diff --git a/fs/compat_ioctl.c b/fs/compat_ioctl.c
index 53bc3659dcef..670b8cbd0896 100644
--- a/fs/compat_ioctl.c
+++ b/fs/compat_ioctl.c
@@ -711,52 +711,9 @@ COMPATIBLE_IOCTL(0x4B50) /* KDGHWCLK - not in the kernel, but don't complain *
COMPATIBLE_IOCTL(0x4B51) /* KDSHWCLK - not in the kernel, but don't complain */

/* Big T */
-COMPATIBLE_IOCTL(TCGETA)
-COMPATIBLE_IOCTL(TCSETA)
-COMPATIBLE_IOCTL(TCSETAW)
-COMPATIBLE_IOCTL(TCSETAF)
-COMPATIBLE_IOCTL(TCSBRK)
-COMPATIBLE_IOCTL(TCXONC)
-COMPATIBLE_IOCTL(TCFLSH)
-COMPATIBLE_IOCTL(TCGETS)
-COMPATIBLE_IOCTL(TCSETS)
-COMPATIBLE_IOCTL(TCSETSW)
-COMPATIBLE_IOCTL(TCSETSF)
COMPATIBLE_IOCTL(TIOCLINUX)
-COMPATIBLE_IOCTL(TIOCSBRK)
-COMPATIBLE_IOCTL(TIOCGDEV)
-COMPATIBLE_IOCTL(TIOCCBRK)
-COMPATIBLE_IOCTL(TIOCGSID)
-COMPATIBLE_IOCTL(TIOCGICOUNT)
-COMPATIBLE_IOCTL(TIOCGEXCL)
/* Little t */
-COMPATIBLE_IOCTL(TIOCGETD)
-COMPATIBLE_IOCTL(TIOCSETD)
-COMPATIBLE_IOCTL(TIOCEXCL)
-COMPATIBLE_IOCTL(TIOCNXCL)
-COMPATIBLE_IOCTL(TIOCCONS)
-COMPATIBLE_IOCTL(TIOCGSOFTCAR)
-COMPATIBLE_IOCTL(TIOCSSOFTCAR)
-COMPATIBLE_IOCTL(TIOCSWINSZ)
-COMPATIBLE_IOCTL(TIOCGWINSZ)
-COMPATIBLE_IOCTL(TIOCMGET)
-COMPATIBLE_IOCTL(TIOCMBIC)
-COMPATIBLE_IOCTL(TIOCMBIS)
-COMPATIBLE_IOCTL(TIOCMSET)
-COMPATIBLE_IOCTL(TIOCNOTTY)
-COMPATIBLE_IOCTL(TIOCSTI)
COMPATIBLE_IOCTL(TIOCOUTQ)
-COMPATIBLE_IOCTL(TIOCSPGRP)
-COMPATIBLE_IOCTL(TIOCGPGRP)
-COMPATIBLE_IOCTL(TIOCSERGETLSR)
-COMPATIBLE_IOCTL(TIOCSRS485)
-COMPATIBLE_IOCTL(TIOCGRS485)
-#ifdef TCGETS2
-COMPATIBLE_IOCTL(TCGETS2)
-COMPATIBLE_IOCTL(TCSETS2)
-COMPATIBLE_IOCTL(TCSETSW2)
-COMPATIBLE_IOCTL(TCSETSF2)
-#endif
/* Little f */
COMPATIBLE_IOCTL(FIOCLEX)
COMPATIBLE_IOCTL(FIONCLEX)
@@ -1219,10 +1176,6 @@ COMPATIBLE_IOCTL(JSIOCGAXES)
COMPATIBLE_IOCTL(JSIOCGBUTTONS)
COMPATIBLE_IOCTL(JSIOCGNAME(0))

-#ifdef TIOCGLTC
-COMPATIBLE_IOCTL(TIOCGLTC)
-COMPATIBLE_IOCTL(TIOCSLTC)
-#endif
#ifdef TIOCSTART
/*
* For these two we have definitions in ioctls.h and/or termios.h on
@@ -1312,10 +1265,6 @@ static long do_ioctl_trans(unsigned int cmd,
* so we must not do a compat_ptr() translation.
*/
switch (cmd) {
- /* Big T */
- case TCSBRKP:
- case TIOCMIWAIT:
- case TIOCSCTTY:
/* RAID */
case HOT_REMOVE_DISK:
case HOT_ADD_DISK:
diff --git a/include/linux/tty.h b/include/linux/tty.h
index c56e3978b00f..414db2bce715 100644
--- a/include/linux/tty.h
+++ b/include/linux/tty.h
@@ -746,8 +746,6 @@ static inline int tty_audit_push(void)
/* tty_ioctl.c */
extern int n_tty_ioctl_helper(struct tty_struct *tty, struct file *file,
unsigned int cmd, unsigned long arg);
-extern long n_tty_compat_ioctl_helper(struct tty_struct *tty, struct file *file,
- unsigned int cmd, unsigned long arg);

/* vt.c */

--
2.11.0