tracing/probes: Fixes for v6.1

- Fix possible NULL pointer dereference  on trace_event_file in kprobe_event_gen_test_exit()
 
 - Fix NULL pointer dereference for trace_array in kprobe_event_gen_test_exit()
 
 - Fix memory leak of filter string for eprobes
 
 - Fix a possible memory leak in rethook_alloc()
 
 - Skip clearing aggrprobe's post_handler in kprobe-on-ftrace case
   which can cause a possible use-after-free
 
 - Fix warning in eprobe filter creation
 
 - Fix eprobe filter creation as it picked the wrong event for the fields
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Merge tag 'trace-probes-v6.1' of git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-trace

Pull tracing/probes fixes from Steven Rostedt:

 - Fix possible NULL pointer dereference on trace_event_file in
   kprobe_event_gen_test_exit()

 - Fix NULL pointer dereference for trace_array in
   kprobe_event_gen_test_exit()

 - Fix memory leak of filter string for eprobes

 - Fix a possible memory leak in rethook_alloc()

 - Skip clearing aggrprobe's post_handler in kprobe-on-ftrace case which
   can cause a possible use-after-free

 - Fix warning in eprobe filter creation

 - Fix eprobe filter creation as it picked the wrong event for the
   fields

* tag 'trace-probes-v6.1' of git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-trace:
  tracing/eprobe: Fix eprobe filter to make a filter correctly
  tracing/eprobe: Fix warning in filter creation
  kprobes: Skip clearing aggrprobe's post_handler in kprobe-on-ftrace case
  rethook: fix a potential memleak in rethook_alloc()
  tracing/eprobe: Fix memory leak of filter string
  tracing: kprobe: Fix potential null-ptr-deref on trace_array in kprobe_event_gen_test_exit()
  tracing: kprobe: Fix potential null-ptr-deref on trace_event_file in kprobe_event_gen_test_exit()
This commit is contained in:
Linus Torvalds 2022-11-20 15:31:20 -08:00
commit c6c67bf9bc
4 changed files with 45 additions and 20 deletions

View file

@ -1766,7 +1766,13 @@ static int __unregister_kprobe_top(struct kprobe *p)
if ((list_p != p) && (list_p->post_handler))
goto noclean;
}
ap->post_handler = NULL;
/*
* For the kprobe-on-ftrace case, we keep the
* post_handler setting to identify this aggrprobe
* armed with kprobe_ipmodify_ops.
*/
if (!kprobe_ftrace(ap))
ap->post_handler = NULL;
}
noclean:
/*

View file

@ -73,6 +73,10 @@ static struct trace_event_file *gen_kretprobe_test;
#define KPROBE_GEN_TEST_ARG3 NULL
#endif
static bool trace_event_file_is_valid(struct trace_event_file *input)
{
return input && !IS_ERR(input);
}
/*
* Test to make sure we can create a kprobe event, then add more
@ -139,6 +143,8 @@ static int __init test_gen_kprobe_cmd(void)
kfree(buf);
return ret;
delete:
if (trace_event_file_is_valid(gen_kprobe_test))
gen_kprobe_test = NULL;
/* We got an error after creating the event, delete it */
ret = kprobe_event_delete("gen_kprobe_test");
goto out;
@ -202,6 +208,8 @@ static int __init test_gen_kretprobe_cmd(void)
kfree(buf);
return ret;
delete:
if (trace_event_file_is_valid(gen_kretprobe_test))
gen_kretprobe_test = NULL;
/* We got an error after creating the event, delete it */
ret = kprobe_event_delete("gen_kretprobe_test");
goto out;
@ -217,10 +225,12 @@ static int __init kprobe_event_gen_test_init(void)
ret = test_gen_kretprobe_cmd();
if (ret) {
WARN_ON(trace_array_set_clr_event(gen_kretprobe_test->tr,
"kprobes",
"gen_kretprobe_test", false));
trace_put_event_file(gen_kretprobe_test);
if (trace_event_file_is_valid(gen_kretprobe_test)) {
WARN_ON(trace_array_set_clr_event(gen_kretprobe_test->tr,
"kprobes",
"gen_kretprobe_test", false));
trace_put_event_file(gen_kretprobe_test);
}
WARN_ON(kprobe_event_delete("gen_kretprobe_test"));
}
@ -229,24 +239,30 @@ static int __init kprobe_event_gen_test_init(void)
static void __exit kprobe_event_gen_test_exit(void)
{
/* Disable the event or you can't remove it */
WARN_ON(trace_array_set_clr_event(gen_kprobe_test->tr,
"kprobes",
"gen_kprobe_test", false));
if (trace_event_file_is_valid(gen_kprobe_test)) {
/* Disable the event or you can't remove it */
WARN_ON(trace_array_set_clr_event(gen_kprobe_test->tr,
"kprobes",
"gen_kprobe_test", false));
/* Now give the file and instance back */
trace_put_event_file(gen_kprobe_test);
}
/* Now give the file and instance back */
trace_put_event_file(gen_kprobe_test);
/* Now unregister and free the event */
WARN_ON(kprobe_event_delete("gen_kprobe_test"));
/* Disable the event or you can't remove it */
WARN_ON(trace_array_set_clr_event(gen_kretprobe_test->tr,
"kprobes",
"gen_kretprobe_test", false));
if (trace_event_file_is_valid(gen_kretprobe_test)) {
/* Disable the event or you can't remove it */
WARN_ON(trace_array_set_clr_event(gen_kretprobe_test->tr,
"kprobes",
"gen_kretprobe_test", false));
/* Now give the file and instance back */
trace_put_event_file(gen_kretprobe_test);
}
/* Now give the file and instance back */
trace_put_event_file(gen_kretprobe_test);
/* Now unregister and free the event */
WARN_ON(kprobe_event_delete("gen_kretprobe_test"));

View file

@ -83,8 +83,10 @@ struct rethook *rethook_alloc(void *data, rethook_handler_t handler)
{
struct rethook *rh = kzalloc(sizeof(struct rethook), GFP_KERNEL);
if (!rh || !handler)
if (!rh || !handler) {
kfree(rh);
return NULL;
}
rh->data = data;
rh->handler = handler;

View file

@ -52,6 +52,7 @@ static void trace_event_probe_cleanup(struct trace_eprobe *ep)
kfree(ep->event_system);
if (ep->event)
trace_event_put_ref(ep->event);
kfree(ep->filter_str);
kfree(ep);
}
@ -645,7 +646,7 @@ new_eprobe_trigger(struct trace_eprobe *ep, struct trace_event_file *file)
INIT_LIST_HEAD(&trigger->list);
if (ep->filter_str) {
ret = create_event_filter(file->tr, file->event_call,
ret = create_event_filter(file->tr, ep->event,
ep->filter_str, false, &filter);
if (ret)
goto error;
@ -903,7 +904,7 @@ static int trace_eprobe_tp_update_arg(struct trace_eprobe *ep, const char *argv[
static int trace_eprobe_parse_filter(struct trace_eprobe *ep, int argc, const char *argv[])
{
struct event_filter *dummy;
struct event_filter *dummy = NULL;
int i, ret, len = 0;
char *p;