linux-kernel - [PATCH] Tracepoints fix reentrancy

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:	Tue, 30 Sep 2008 01:51:12 -0400
From:	Mathieu Desnoyers <mathieu.desnoyers@...ymtl.ca>
To:	Ingo Molnar <mingo@...e.hu>, "Frank Ch. Eigler" <fche@...hat.com>,
	Lai Jiangshan <laijs@...fujitsu.com>
Cc:	linux-kernel@...r.kernel.org
Subject: [PATCH] Tracepoints fix reentrancy

The tracepoints had the same problem markers did have wrt reentrancy. Apply a
similar fix using a rcu_barrier after each tracepoint mutex lock.

Signed-off-by: Mathieu Desnoyers <mathieu.desnoyers@...ymtl.ca>
CC: Ingo Molnar <mingo@...e.hu>
CC: "Frank Ch. Eigler" <fche@...hat.com>
CC: Lai Jiangshan <laijs@...fujitsu.com>
---
 kernel/tracepoint.c |    4 ++++
 1 file changed, 4 insertions(+)

Index: linux-2.6-lttng/kernel/tracepoint.c
===================================================================
--- linux-2.6-lttng.orig/kernel/tracepoint.c	2008-09-30 01:38:39.000000000 -0400
+++ linux-2.6-lttng/kernel/tracepoint.c	2008-09-30 01:39:56.000000000 -0400
@@ -361,6 +361,8 @@ int tracepoint_probe_register(const char
 	mutex_lock(&tracepoints_mutex);
 	entry = get_tracepoint(name);
 	WARN_ON(!entry);
+	if (entry->rcu_pending)
+		rcu_barrier_sched();
 	tracepoint_entry_free_old(entry, old);
 end:
 	mutex_unlock(&tracepoints_mutex);
@@ -397,6 +399,8 @@ int tracepoint_probe_unregister(const ch
 	entry = get_tracepoint(name);
 	if (!entry)
 		goto end;
+	if (entry->rcu_pending)
+		rcu_barrier_sched();
 	tracepoint_entry_free_old(entry, old);
 	remove_tracepoint(name);	/* Ignore busy error message */
 	ret = 0;
-- 
Mathieu Desnoyers
OpenPGP key fingerprint: 8CD5 52C3 8E3C 4140 715F  BA06 3F25 A8FE 3BAE 9A68
--
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/