This is a note to let you know that I've just added the patch titled
perf probe: Fix memory leakage when the probe point is not found
to the 5.8-stable tree which can be found at:
http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary
The filename of the patch is:
perf-probe-fix-memory-leakage-when-the-probe-point-is-not-found.patch
and it can be found in the queue-5.8 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@xxxxxxxxxxxxxxx> know about it.
>From 12d572e785b15bc764e956caaa8a4c846fd15694 Mon Sep 17 00:00:00 2001
From: Masami Hiramatsu <mhiramat@xxxxxxxxxx>
Date: Fri, 10 Jul 2020 22:11:23 +0900
Subject: perf probe: Fix memory leakage when the probe point is not found
From: Masami Hiramatsu <mhiramat@xxxxxxxxxx>
commit 12d572e785b15bc764e956caaa8a4c846fd15694 upstream.
Fix the memory leakage in debuginfo__find_trace_events() when the probe
point is not found in the debuginfo. If there is no probe point found in
the debuginfo, debuginfo__find_probes() will NOT return -ENOENT, but 0.
Thus the caller of debuginfo__find_probes() must check the tf.ntevs and
release the allocated memory for the array of struct probe_trace_event.
The current code releases the memory only if the debuginfo__find_probes()
hits an error but not checks tf.ntevs. In the result, the memory allocated
on *tevs are not released if tf.ntevs == 0.
This fixes the memory leakage by checking tf.ntevs == 0 in addition to
ret < 0.
Fixes: ff741783506c ("perf probe: Introduce debuginfo to encapsulate dwarf information")
Signed-off-by: Masami Hiramatsu <mhiramat@xxxxxxxxxx>
Reviewed-by: Srikar Dronamraju <srikar@xxxxxxxxxxxxxxxxxx>
Cc: Andi Kleen <ak@xxxxxxxxxxxxxxx>
Cc: Oleg Nesterov <oleg@xxxxxxxxxx>
Cc: stable@xxxxxxxxxxxxxxx
Link: http://lore.kernel.org/lkml/159438668346.62703.10887420400718492503.stgit@devnote2
Signed-off-by: Arnaldo Carvalho de Melo <acme@xxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
tools/perf/util/probe-finder.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
--- a/tools/perf/util/probe-finder.c
+++ b/tools/perf/util/probe-finder.c
@@ -1467,7 +1467,7 @@ int debuginfo__find_trace_events(struct
if (ret >= 0 && tf.pf.skip_empty_arg)
ret = fill_empty_trace_arg(pev, tf.tevs, tf.ntevs);
- if (ret < 0) {
+ if (ret < 0 || tf.ntevs == 0) {
for (i = 0; i < tf.ntevs; i++)
clear_probe_trace_event(&tf.tevs[i]);
zfree(tevs);
Patches currently in stable-queue which might be from mhiramat@xxxxxxxxxx are
queue-5.8/perf-probe-fix-wrong-variable-warning-when-the-probe-point-is-not-found.patch
queue-5.8/perf-probe-fix-memory-leakage-when-the-probe-point-is-not-found.patch
queue-5.8/bootconfig-fix-to-find-the-initargs-correctly.patch
queue-5.8/kprobes-fix-null-pointer-dereference-at-kprobe_ftrace_handler.patch
