From 88c48db9788862d0290831d081bc3c64e13b592f Mon Sep 17 00:00:00 2001 From: Eric Paris Date: Wed, 29 Apr 2009 14:00:25 -0400 Subject: SELinux: drop secondary_ops->sysctl We are still calling secondary_ops->sysctl even though the capabilities module does not define a sysctl operation. Signed-off-by: Eric Paris Acked-by: Stephen Smalley Signed-off-by: James Morris --- security/selinux/hooks.c | 4 ---- 1 file changed, 4 deletions(-) (limited to 'security/selinux/hooks.c') diff --git a/security/selinux/hooks.c b/security/selinux/hooks.c index ba808ef6babb..dd19ba81201f 100644 --- a/security/selinux/hooks.c +++ b/security/selinux/hooks.c @@ -1980,10 +1980,6 @@ static int selinux_sysctl(ctl_table *table, int op) u32 tsid, sid; int rc; - rc = secondary_ops->sysctl(table, op); - if (rc) - return rc; - sid = current_sid(); rc = selinux_sysctl_get_sid(table, (op == 0001) ? -- cgit From 3bcac0263f0b45e67a64034ebcb69eb9abb742f4 Mon Sep 17 00:00:00 2001 From: David Howells Date: Wed, 29 Apr 2009 13:45:05 +0100 Subject: SELinux: Don't flush inherited SIGKILL during execve() Don't flush inherited SIGKILL during execve() in SELinux's post cred commit hook. This isn't really a security problem: if the SIGKILL came before the credentials were changed, then we were right to receive it at the time, and should honour it; if it came after the creds were changed, then we definitely should honour it; and in any case, all that will happen is that the process will be scrapped before it ever returns to userspace. Signed-off-by: David Howells Signed-off-by: Oleg Nesterov Signed-off-by: James Morris --- include/linux/sched.h | 1 + kernel/signal.c | 11 ++++++++--- security/selinux/hooks.c | 9 +++++---- 3 files changed, 14 insertions(+), 7 deletions(-) (limited to 'security/selinux/hooks.c') diff --git a/include/linux/sched.h b/include/linux/sched.h index 1d19c025f9d2..d3b787c7aef3 100644 --- a/include/linux/sched.h +++ b/include/linux/sched.h @@ -1875,6 +1875,7 @@ extern void sched_dead(struct task_struct *p); extern void proc_caches_init(void); extern void flush_signals(struct task_struct *); +extern void __flush_signals(struct task_struct *); extern void ignore_signals(struct task_struct *); extern void flush_signal_handlers(struct task_struct *, int force_default); extern int dequeue_signal(struct task_struct *tsk, sigset_t *mask, siginfo_t *info); diff --git a/kernel/signal.c b/kernel/signal.c index 1c8814481a11..f93efec14ff5 100644 --- a/kernel/signal.c +++ b/kernel/signal.c @@ -238,14 +238,19 @@ void flush_sigqueue(struct sigpending *queue) /* * Flush all pending signals for a task. */ +void __flush_signals(struct task_struct *t) +{ + clear_tsk_thread_flag(t, TIF_SIGPENDING); + flush_sigqueue(&t->pending); + flush_sigqueue(&t->signal->shared_pending); +} + void flush_signals(struct task_struct *t) { unsigned long flags; spin_lock_irqsave(&t->sighand->siglock, flags); - clear_tsk_thread_flag(t, TIF_SIGPENDING); - flush_sigqueue(&t->pending); - flush_sigqueue(&t->signal->shared_pending); + __flush_signals(t); spin_unlock_irqrestore(&t->sighand->siglock, flags); } diff --git a/security/selinux/hooks.c b/security/selinux/hooks.c index dd19ba81201f..5a345115036c 100644 --- a/security/selinux/hooks.c +++ b/security/selinux/hooks.c @@ -2394,11 +2394,12 @@ static void selinux_bprm_committed_creds(struct linux_binprm *bprm) memset(&itimer, 0, sizeof itimer); for (i = 0; i < 3; i++) do_setitimer(i, &itimer, NULL); - flush_signals(current); spin_lock_irq(¤t->sighand->siglock); - flush_signal_handlers(current, 1); - sigemptyset(¤t->blocked); - recalc_sigpending(); + if (!(current->signal->flags & SIGNAL_GROUP_EXIT)) { + __flush_signals(current); + flush_signal_handlers(current, 1); + sigemptyset(¤t->blocked); + } spin_unlock_irq(¤t->sighand->siglock); } -- cgit From ecd6de3c88e8cbcad175b2eab48ba05c2014f7b6 Mon Sep 17 00:00:00 2001 From: Oleg Nesterov Date: Wed, 29 Apr 2009 16:02:24 +0200 Subject: selinux: selinux_bprm_committed_creds() should wake up ->real_parent, not ->parent. We shouldn't worry about the tracer if current is ptraced, exec() must not succeed if the tracer has no rights to trace this task after cred changing. But we should notify ->real_parent which is, well, real parent. Also, we don't need _irq to take tasklist, and we don't need parent's ->siglock to wake_up_interruptible(real_parent->signal->wait_chldexit). Since we hold tasklist, real_parent->signal must be stable. Otherwise spin_lock(siglock) is not safe too and can't help anyway. Signed-off-by: Oleg Nesterov Signed-off-by: James Morris --- security/selinux/hooks.c | 11 +++-------- 1 file changed, 3 insertions(+), 8 deletions(-) (limited to 'security/selinux/hooks.c') diff --git a/security/selinux/hooks.c b/security/selinux/hooks.c index 5a345115036c..39046ddd90a9 100644 --- a/security/selinux/hooks.c +++ b/security/selinux/hooks.c @@ -2371,10 +2371,8 @@ static void selinux_bprm_committed_creds(struct linux_binprm *bprm) { const struct task_security_struct *tsec = current_security(); struct itimerval itimer; - struct sighand_struct *psig; u32 osid, sid; int rc, i; - unsigned long flags; osid = tsec->osid; sid = tsec->sid; @@ -2405,12 +2403,9 @@ static void selinux_bprm_committed_creds(struct linux_binprm *bprm) /* Wake up the parent if it is waiting so that it can recheck * wait permission to the new task SID. */ - read_lock_irq(&tasklist_lock); - psig = current->parent->sighand; - spin_lock_irqsave(&psig->siglock, flags); - wake_up_interruptible(¤t->parent->signal->wait_chldexit); - spin_unlock_irqrestore(&psig->siglock, flags); - read_unlock_irq(&tasklist_lock); + read_lock(&tasklist_lock); + wake_up_interruptible(¤t->real_parent->signal->wait_chldexit); + read_unlock(&tasklist_lock); } /* superblock security operations */ -- cgit