linux-kernel - [PATCH] signals: sys_ssetmask/sys_rt_sigsuspend should use set_current

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [thread-next>] [day] [month] [year] [list]

Date:	Mon, 11 Jul 2011 18:01:02 +0200
From:	Oleg Nesterov <oleg@...hat.com>
To:	Andrew Morton <akpm@...ux-foundation.org>
Cc:	Tejun Heo <tj@...nel.org>,
	Matt Fleming <matt.fleming@...ux.intel.com>,
	linux-kernel@...r.kernel.org
Subject: [PATCH] signals: sys_ssetmask/sys_rt_sigsuspend should use
	set_current_blocked()

sys_ssetmask(), sys_rt_sigsuspend() and compat_sys_rt_sigsuspend()
change ->blocked directly. This is not correct, see the changelog in
e6fa16ab "signal: sigprocmask() should do retarget_shared_pending()"

Change them to use set_current_blocked().

Another change is that now we are doing ->saved_sigmask = ->blocked
lockless, it doesn't make any sense to do this under ->siglock.

Signed-off-by: Oleg Nesterov <oleg@...hat.com>
---

 kernel/signal.c |   17 +++++------------
 kernel/compat.c |    5 +----
 2 files changed, 6 insertions(+), 16 deletions(-)

--- ptrace/kernel/signal.c~4_sigsuspend	2011-07-10 16:19:27.000000000 +0200
+++ ptrace/kernel/signal.c	2011-07-11 17:27:48.000000000 +0200
@@ -2986,15 +2986,11 @@ SYSCALL_DEFINE0(sgetmask)
 
 SYSCALL_DEFINE1(ssetmask, int, newmask)
 {
-	int old;
-
-	spin_lock_irq(&current->sighand->siglock);
-	old = current->blocked.sig[0];
+	int old = current->blocked.sig[0];
+	sigset_t newset;
 
-	siginitset(&current->blocked, newmask & ~(sigmask(SIGKILL)|
-						  sigmask(SIGSTOP)));
-	recalc_sigpending();
-	spin_unlock_irq(&current->sighand->siglock);
+	siginitset(&newset, newmask & ~(sigmask(SIGKILL) | sigmask(SIGSTOP)));
+	set_current_blocked(&newset);
 
 	return old;
 }
@@ -3051,11 +3047,8 @@ SYSCALL_DEFINE2(rt_sigsuspend, sigset_t 
 		return -EFAULT;
 	sigdelsetmask(&newset, sigmask(SIGKILL)|sigmask(SIGSTOP));
 
-	spin_lock_irq(&current->sighand->siglock);
 	current->saved_sigmask = current->blocked;
-	current->blocked = newset;
-	recalc_sigpending();
-	spin_unlock_irq(&current->sighand->siglock);
+	set_current_blocked(&newset);
 
 	current->state = TASK_INTERRUPTIBLE;
 	schedule();
--- ptrace/kernel/compat.c~4_sigsuspend	2011-05-26 14:48:21.000000000 +0200
+++ ptrace/kernel/compat.c	2011-07-11 17:53:57.000000000 +0200
@@ -991,11 +991,8 @@ asmlinkage long compat_sys_rt_sigsuspend
 	sigset_from_compat(&newset, &newset32);
 	sigdelsetmask(&newset, sigmask(SIGKILL)|sigmask(SIGSTOP));
 
-	spin_lock_irq(&current->sighand->siglock);
 	current->saved_sigmask = current->blocked;
-	current->blocked = newset;
-	recalc_sigpending();
-	spin_unlock_irq(&current->sighand->siglock);
+	set_current_blocked(&newset);
 
 	current->state = TASK_INTERRUPTIBLE;
 	schedule();

--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/