24ec839c43
Fix the locking of signal->tty.
Use ->sighand->siglock to protect ->signal->tty; this lock is already used
by most other members of ->signal/->sighand. And unless we are 'current'
or the tasklist_lock is held we need ->siglock to access ->signal anyway.
(NOTE: sys_unshare() is broken wrt ->sighand locking rules)
Note that tty_mutex is held over tty destruction, so while holding
tty_mutex any tty pointer remains valid. Otherwise the lifetime of ttys
are governed by their open file handles. This leaves some holes for tty
access from signal->tty (or any other non file related tty access).
It solves the tty SLAB scribbles we were seeing.
(NOTE: the change from group_send_sig_info to __group_send_sig_info needs to
be examined by someone familiar with the security framework, I think
it is safe given the SEND_SIG_PRIV from other __group_send_sig_info
invocations)
[schwidefsky@de.ibm.com: 3270 fix]
[akpm@osdl.org: various post-viro fixes]
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Acked-by: Alan Cox <alan@redhat.com>
Cc: Oleg Nesterov <oleg@tv-sign.ru>
Cc: Prarit Bhargava <prarit@redhat.com>
Cc: Chris Wright <chrisw@sous-sol.org>
Cc: Roland McGrath <roland@redhat.com>
Cc: Stephen Smalley <sds@tycho.nsa.gov>
Cc: James Morris <jmorris@namei.org>
Cc: "David S. Miller" <davem@davemloft.net>
Cc: Jeff Dike <jdike@addtoit.com>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: Jan Kara <jack@ucw.cz>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
89 lines
1.9 KiB
C
89 lines
1.9 KiB
C
/*
|
|
* Copyright (C) 2000, 2001 Jeff Dike (jdike@karaya.com)
|
|
* Licensed under the GPL
|
|
*/
|
|
|
|
#include "linux/slab.h"
|
|
#include "linux/smp_lock.h"
|
|
#include "linux/ptrace.h"
|
|
#include "asm/ptrace.h"
|
|
#include "asm/pgtable.h"
|
|
#include "asm/tlbflush.h"
|
|
#include "asm/uaccess.h"
|
|
#include "user_util.h"
|
|
#include "kern_util.h"
|
|
#include "mem_user.h"
|
|
#include "kern.h"
|
|
#include "irq_user.h"
|
|
#include "tlb.h"
|
|
#include "os.h"
|
|
#include "choose-mode.h"
|
|
#include "mode_kern.h"
|
|
|
|
void flush_thread(void)
|
|
{
|
|
arch_flush_thread(¤t->thread.arch);
|
|
CHOOSE_MODE(flush_thread_tt(), flush_thread_skas());
|
|
}
|
|
|
|
void start_thread(struct pt_regs *regs, unsigned long eip, unsigned long esp)
|
|
{
|
|
CHOOSE_MODE_PROC(start_thread_tt, start_thread_skas, regs, eip, esp);
|
|
}
|
|
|
|
#ifdef CONFIG_TTY_LOG
|
|
extern void log_exec(char **argv, void *tty);
|
|
#endif
|
|
|
|
static long execve1(char *file, char __user * __user *argv,
|
|
char __user *__user *env)
|
|
{
|
|
long error;
|
|
struct tty_struct *tty;
|
|
|
|
#ifdef CONFIG_TTY_LOG
|
|
mutex_lock(&tty_mutex);
|
|
tty = get_current_tty();
|
|
if (tty)
|
|
log_exec(argv, tty);
|
|
mutex_unlock(&tty_mutex);
|
|
#endif
|
|
error = do_execve(file, argv, env, ¤t->thread.regs);
|
|
if (error == 0){
|
|
task_lock(current);
|
|
current->ptrace &= ~PT_DTRACE;
|
|
#ifdef SUBARCH_EXECVE1
|
|
SUBARCH_EXECVE1(¤t->thread.regs.regs);
|
|
#endif
|
|
task_unlock(current);
|
|
set_cmdline(current_cmd());
|
|
}
|
|
return(error);
|
|
}
|
|
|
|
long um_execve(char *file, char __user *__user *argv, char __user *__user *env)
|
|
{
|
|
long err;
|
|
|
|
err = execve1(file, argv, env);
|
|
if(!err)
|
|
do_longjmp(current->thread.exec_buf, 1);
|
|
return(err);
|
|
}
|
|
|
|
long sys_execve(char __user *file, char __user *__user *argv,
|
|
char __user *__user *env)
|
|
{
|
|
long error;
|
|
char *filename;
|
|
|
|
lock_kernel();
|
|
filename = getname(file);
|
|
error = PTR_ERR(filename);
|
|
if (IS_ERR(filename)) goto out;
|
|
error = execve1(filename, argv, env);
|
|
putname(filename);
|
|
out:
|
|
unlock_kernel();
|
|
return(error);
|
|
}
|