linux-kernel - [PATCH 16/17] uprobes: Allocate ->utask before handler

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

Message-Id: <1385533203-10014-17-git-send-email-namhyung@kernel.org>
Date:	Wed, 27 Nov 2013 15:20:02 +0900
From:	Namhyung Kim <namhyung@...nel.org>
To:	Steven Rostedt <rostedt@...dmis.org>,
	Oleg Nesterov <oleg@...hat.com>
Cc:	Masami Hiramatsu <masami.hiramatsu.pt@...achi.com>,
	Hyeoncheol Lee <cheol.lee@....com>,
	Srikar Dronamraju <srikar@...ux.vnet.ibm.com>,
	"zhangwei(Jovi)" <jovi.zhangwei@...wei.com>,
	Arnaldo Carvalho de Melo <acme@...stprotocols.net>,
	Hemant Kumar <hkshaw@...ux.vnet.ibm.com>,
	LKML <linux-kernel@...r.kernel.org>,
	Namhyung Kim <namhyung.kim@....com>
Subject: [PATCH 16/17] uprobes: Allocate ->utask before handler_chain() for tracing handlers

From: Oleg Nesterov <oleg@...hat.com>

uprobe_trace_print() and uprobe_perf_print() need to pass the additional
info to call_fetch() methods, currently there is no simple way to do this.

current->utask looks like a natural place to hold this info, but we need
to allocate it before handler_chain().

This is a bit unfortunate, perhaps we will find a better solution later,
but this is simnple and should work right now.

Signed-off-by: Oleg Nesterov <oleg@...hat.com>
Cc: Srikar Dronamraju <srikar@...ux.vnet.ibm.com>
Cc: Masami Hiramatsu <masami.hiramatsu.pt@...achi.com>
Signed-off-by: Namhyung Kim <namhyung@...nel.org>
---
 kernel/events/uprobes.c | 4 ++++
 1 file changed, 4 insertions(+)

diff --git a/kernel/events/uprobes.c b/kernel/events/uprobes.c
index ad8e1bdca70e..a1aa4aed029c 100644
--- a/kernel/events/uprobes.c
+++ b/kernel/events/uprobes.c
@@ -1744,6 +1744,10 @@ static void handle_swbp(struct pt_regs *regs)
 	if (unlikely(!test_bit(UPROBE_COPY_INSN, &uprobe->flags)))
 		goto out;
 
+	/* Tracing handlers use ->utask to communicate with fetch methods */
+	if (!get_utask())
+		goto out;
+
 	handler_chain(uprobe, regs);
 	if (can_skip_sstep(uprobe, regs))
 		goto out;
-- 
1.7.11.7

--
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/