kernel-fxtec-pro1x/tools/perf/util/strlist.c
Suzuki K. Poulose 4592281403 perf tools: Remove the node from rblist in strlist__remove
The following commit:

author	David Ahern <dsahern@gmail.com>
	Tue, 31 Jul 2012 04:31:33 +0000 (22:31 -0600)
committer	Arnaldo Carvalho de Melo <acme@redhat.com>
	Fri, 3 Aug 2012 13:39:51 +0000 (10:39 -0300)
commit	ee8dd3ca43

causes a double free during a probe deletion as the node is never
removed from the list via strlist__remove(), even though it gets
'deleted' (read free()'d). This causes a double free when we do
strlist__delete() as the node is already deleted but present in the
rblist.

[suzukikp@suzukikp perf]$ sudo ./perf probe -a do_fork
Added new event:
  probe:do_fork        (on do_fork)

You can now use it in all perf tools, such as:

	perf record -e probe:do_fork -aR sleep 1

[suzukikp@suzukikp perf]$ sudo ./perf probe -d do_fork
Removed event: probe:do_fork
*** glibc detected *** ./perf: double free or corruption (fasttop): 0x000000000133d600 ***
======= Backtrace: =========
/lib64/libc.so.6[0x38eec7dda6]
./perf(rblist__delete+0x5c)[0x47d3dc]
./perf(del_perf_probe_events+0xb6)[0x47b826]
./perf(cmd_probe+0x471)[0x42c8d1]
./perf[0x4150b3]
./perf(main+0x501)[0x4148e1]
/lib64/libc.so.6(__libc_start_main+0xed)[0x38eec2169d]
./perf[0x414a61]

Make sure we remove the node from the rblist before we delete the node.
The rblist__remove_node() will invoke rblist->node_delete, which  will
take care of deleting the node with the suitable function provided by
the user.

Reported-by: Ananth N. Mavinakayanahalli <ananth@in.ibm.com>
Signed-off-by: Suzuki K. Poulose <suzuki@in.ibm.com>
Acked-by: David Ahern <dsahern@gmail.com>
Cc: Ananth N Mavinakayanahalli <ananth@in.ibm.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/20120829055840.7802.1459.stgit@suzukikp.in.ibm.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2012-09-05 17:36:42 -03:00

172 lines
3.5 KiB
C

/*
* (c) 2009 Arnaldo Carvalho de Melo <acme@redhat.com>
*
* Licensed under the GPLv2.
*/
#include "strlist.h"
#include <errno.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
static
struct rb_node *strlist__node_new(struct rblist *rblist, const void *entry)
{
const char *s = entry;
struct rb_node *rc = NULL;
struct strlist *strlist = container_of(rblist, struct strlist, rblist);
struct str_node *snode = malloc(sizeof(*snode));
if (snode != NULL) {
if (strlist->dupstr) {
s = strdup(s);
if (s == NULL)
goto out_delete;
}
snode->s = s;
rc = &snode->rb_node;
}
return rc;
out_delete:
free(snode);
return NULL;
}
static void str_node__delete(struct str_node *self, bool dupstr)
{
if (dupstr)
free((void *)self->s);
free(self);
}
static
void strlist__node_delete(struct rblist *rblist, struct rb_node *rb_node)
{
struct strlist *slist = container_of(rblist, struct strlist, rblist);
struct str_node *snode = container_of(rb_node, struct str_node, rb_node);
str_node__delete(snode, slist->dupstr);
}
static int strlist__node_cmp(struct rb_node *rb_node, const void *entry)
{
const char *str = entry;
struct str_node *snode = container_of(rb_node, struct str_node, rb_node);
return strcmp(snode->s, str);
}
int strlist__add(struct strlist *self, const char *new_entry)
{
return rblist__add_node(&self->rblist, new_entry);
}
int strlist__load(struct strlist *self, const char *filename)
{
char entry[1024];
int err;
FILE *fp = fopen(filename, "r");
if (fp == NULL)
return errno;
while (fgets(entry, sizeof(entry), fp) != NULL) {
const size_t len = strlen(entry);
if (len == 0)
continue;
entry[len - 1] = '\0';
err = strlist__add(self, entry);
if (err != 0)
goto out;
}
err = 0;
out:
fclose(fp);
return err;
}
void strlist__remove(struct strlist *slist, struct str_node *snode)
{
rblist__remove_node(&slist->rblist, &snode->rb_node);
}
struct str_node *strlist__find(struct strlist *slist, const char *entry)
{
struct str_node *snode = NULL;
struct rb_node *rb_node = rblist__find(&slist->rblist, entry);
if (rb_node)
snode = container_of(rb_node, struct str_node, rb_node);
return snode;
}
static int strlist__parse_list_entry(struct strlist *self, const char *s)
{
if (strncmp(s, "file://", 7) == 0)
return strlist__load(self, s + 7);
return strlist__add(self, s);
}
int strlist__parse_list(struct strlist *self, const char *s)
{
char *sep;
int err;
while ((sep = strchr(s, ',')) != NULL) {
*sep = '\0';
err = strlist__parse_list_entry(self, s);
*sep = ',';
if (err != 0)
return err;
s = sep + 1;
}
return *s ? strlist__parse_list_entry(self, s) : 0;
}
struct strlist *strlist__new(bool dupstr, const char *slist)
{
struct strlist *self = malloc(sizeof(*self));
if (self != NULL) {
rblist__init(&self->rblist);
self->rblist.node_cmp = strlist__node_cmp;
self->rblist.node_new = strlist__node_new;
self->rblist.node_delete = strlist__node_delete;
self->dupstr = dupstr;
if (slist && strlist__parse_list(self, slist) != 0)
goto out_error;
}
return self;
out_error:
free(self);
return NULL;
}
void strlist__delete(struct strlist *self)
{
if (self != NULL)
rblist__delete(&self->rblist);
}
struct str_node *strlist__entry(const struct strlist *slist, unsigned int idx)
{
struct str_node *snode = NULL;
struct rb_node *rb_node;
rb_node = rblist__entry(&slist->rblist, idx);
if (rb_node)
snode = container_of(rb_node, struct str_node, rb_node);
return snode;
}