AuxXxilium/linux_dsm_epyc7002
1
0
Fork 0
mirror of https://github.com/AuxXxilium/linux_dsm_epyc7002.git synced 2024-11-24 04:40:51 +07:00
Code Issues Actions Packages Projects Releases Wiki Activity

tty: the vhangup syscall is racy

Browse Source 
We now have the infrastructure to sort this out but rather than teaching
the syscall tty lock rules we move the hard work into a tty helper

Signed-off-by: Alan Cox <alan@redhat.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This commit is contained in:
Alan Cox 2008-10-13 10:40:30 +01:00 committed by Linus Torvalds
parent 216ba023a9
commit 2cb5998b5f
3 changed files with 21 additions and 2 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

19
drivers/char/tty_io.c
View File

@ -729,6 +729,25 @@ void tty_vhangup(struct tty_struct *tty)
EXPORT_SYMBOL(tty_vhangup); EXPORT_SYMBOL(tty_vhangup);
/**
* tty_vhangup_self - process vhangup for own ctty
*
* Perform a vhangup on the current controlling tty
*/
void tty_vhangup_self(void)
{
struct tty_struct *tty;
mutex_lock(&tty_mutex);
tty = get_current_tty();
if (tty) {
tty_vhangup(tty);
tty_kref_put(tty);
}
mutex_unlock(&tty_mutex);
}
/** /**
* tty_hung_up_p - was tty hung up * tty_hung_up_p - was tty hung up
* @filp: file pointer of tty * @filp: file pointer of tty

3
fs/open.c
View File

@ -1141,8 +1141,7 @@ EXPORT_SYMBOL(sys_close);
asmlinkage long sys_vhangup(void) asmlinkage long sys_vhangup(void)
{ {
if (capable(CAP_SYS_TTY_CONFIG)) { if (capable(CAP_SYS_TTY_CONFIG)) {
/* XXX: this needs locking */ tty_vhangup_self();
tty_vhangup(current->signal->tty);
return 0; return 0;
} }
return -EPERM; return -EPERM;

1
include/linux/tty.h
View File

@ -361,6 +361,7 @@ extern int is_ignored(int sig);
extern int tty_signal(int sig, struct tty_struct *tty); extern int tty_signal(int sig, struct tty_struct *tty);
extern void tty_hangup(struct tty_struct *tty); extern void tty_hangup(struct tty_struct *tty);
extern void tty_vhangup(struct tty_struct *tty); extern void tty_vhangup(struct tty_struct *tty);
extern void tty_vhangup_self(void);
extern void tty_unhangup(struct file *filp); extern void tty_unhangup(struct file *filp);
extern int tty_hung_up_p(struct file *filp); extern int tty_hung_up_p(struct file *filp);
extern void do_SAK(struct tty_struct *tty); extern void do_SAK(struct tty_struct *tty);