Commit 97e8230f authored by Masami Hiramatsu (Google)'s avatar Masami Hiramatsu (Google)
Browse files

tracing: uprobe-event: Allocate string buffers from heap 

Allocate temporary string buffers for parsing uprobe-events
from heap instead of stack.

Link: https://lore.kernel.org/all/175323429593.57270.12369235525923902341.stgit@devnote2/



Signed-off-by: default avatarMasami Hiramatsu (Google) <mhiramat@kernel.org>
Reviewed-by: default avatarSteven Rostedt (Google) <rostedt@goodmis.org>
parent 4c6edb43

kernel/trace/trace_uprobe.c

+19 −9
Original line number Diff line number Diff line
@@ -8,6 +8,7 @@ 
#define pr_fmt(fmt)	"trace_uprobe: " fmt



#include <linux/bpf-cgroup.h>

#include <linux/cleanup.h>

#include <linux/ctype.h>

#include <linux/filter.h>

#include <linux/module.h>
@@ -19,6 +20,7 @@ 
#include <linux/uaccess.h>

#include <linux/uprobes.h>



#include "trace.h"

#include "trace_dynevent.h"

#include "trace_probe.h"

#include "trace_probe_tmpl.h"
@@ -537,15 +539,15 @@ static int register_trace_uprobe(struct trace_uprobe *tu) 
 */

static int __trace_uprobe_create(int argc, const char **argv)

{

	struct trace_uprobe *tu;

	const char *event = NULL, *group = UPROBE_EVENT_SYSTEM;

	char *arg, *filename, *rctr, *rctr_end, *tmp;

	char buf[MAX_EVENT_NAME_LEN];

	char gbuf[MAX_EVENT_NAME_LEN];

	enum probe_print_type ptype;

	struct path path;

	unsigned long offset, ref_ctr_offset;

	char *gbuf __free(kfree) = NULL;

	char *buf __free(kfree) = NULL;

	enum probe_print_type ptype;

	struct trace_uprobe *tu;

	bool is_return = false;

	struct path path;

	int i, ret;



	ref_ctr_offset = 0;
@@ -653,6 +655,10 @@ static int __trace_uprobe_create(int argc, const char **argv) 
	/* setup a probe */

	trace_probe_log_set_index(0);

	if (event) {

		gbuf = kmalloc(MAX_EVENT_NAME_LEN, GFP_KERNEL);

		if (!gbuf)

			goto fail_mem;



		ret = traceprobe_parse_event_name(&event, &group, gbuf,

						  event - argv[0]);

		if (ret)
@@ -664,15 +670,16 @@ static int __trace_uprobe_create(int argc, const char **argv) 
		char *ptr;



		tail = kstrdup(kbasename(filename), GFP_KERNEL);

		if (!tail) {

			ret = -ENOMEM;

			goto fail_address_parse;

		}

		if (!tail)

			goto fail_mem;



		ptr = strpbrk(tail, ".-_");

		if (ptr)

			*ptr = '\0';



		buf = kmalloc(MAX_EVENT_NAME_LEN, GFP_KERNEL);

		if (!buf)

			goto fail_mem;

		snprintf(buf, MAX_EVENT_NAME_LEN, "%c_%s_0x%lx", 'p', tail, offset);

		event = buf;

		kfree(tail);
@@ -724,6 +731,9 @@ static int __trace_uprobe_create(int argc, const char **argv) 
	trace_probe_log_clear();

	return ret;



fail_mem:

	ret = -ENOMEM;



fail_address_parse:

	trace_probe_log_clear();

	path_put(&path);