linux-kernel - [PATCH V3 08/13] ftrace: Add perf text poke events for ftrace trampolines

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 for Android: free password hash cracker in your pocket

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

Date:   Fri, 28 Feb 2020 15:51:20 +0200
From:   Adrian Hunter <adrian.hunter@...el.com>
To:     Peter Zijlstra <peterz@...radead.org>
Cc:     Ingo Molnar <mingo@...hat.com>,
        Masami Hiramatsu <mhiramat@...nel.org>,
        Steven Rostedt <rostedt@...dmis.org>,
        Borislav Petkov <bp@...en8.de>,
        "H . Peter Anvin" <hpa@...or.com>, x86@...nel.org,
        Mark Rutland <mark.rutland@....com>,
        Alexander Shishkin <alexander.shishkin@...ux.intel.com>,
        Mathieu Poirier <mathieu.poirier@...aro.org>,
        Leo Yan <leo.yan@...aro.org>,
        Arnaldo Carvalho de Melo <acme@...nel.org>,
        Jiri Olsa <jolsa@...hat.com>, linux-kernel@...r.kernel.org
Subject: [PATCH V3 08/13] ftrace: Add perf text poke events for ftrace trampolines

Add perf text poke events for ftrace trampolines when created and when
freed.

Signed-off-by: Adrian Hunter <adrian.hunter@...el.com>
---
 arch/x86/kernel/ftrace.c | 5 +++++
 1 file changed, 5 insertions(+)

diff --git a/arch/x86/kernel/ftrace.c b/arch/x86/kernel/ftrace.c
index 34e1dd495ce4..cec2ffae9e60 100644
--- a/arch/x86/kernel/ftrace.c
+++ b/arch/x86/kernel/ftrace.c
@@ -410,6 +410,8 @@ static void create_trampoline(struct ftrace_ops *ops)
 	ftrace_add_trampoline_to_kallsyms(ops);
 	perf_event_ksymbol(PERF_RECORD_KSYMBOL_TYPE_OOL, (u64)trampoline,
 			   tramp_size, false, FTRACE_TRAMPOLINE_SYM);
+	/* Record the perf text poke event after the ksymbol register event */
+	perf_event_text_poke(trampoline, NULL, 0, trampoline, tramp_size);
 
 	set_vm_flush_reset_perms(trampoline);
 
@@ -537,6 +539,9 @@ void arch_ftrace_trampoline_free(struct ftrace_ops *ops)
 	if (!ops || !(ops->flags & FTRACE_OPS_FL_ALLOC_TRAMP))
 		return;
 
+	/* Record the text poke event before the ksymbol unregister event */
+	perf_event_text_poke((void *)ops->trampoline, (void *)ops->trampoline,
+			     ops->trampoline_size, NULL, 0);
 	perf_event_ksymbol(PERF_RECORD_KSYMBOL_TYPE_OOL, (u64)ops->trampoline,
 			   ops->trampoline_size, true, FTRACE_TRAMPOLINE_SYM);
 	/* Remove from kallsyms after the perf events */
-- 
2.17.1