lkml.org 
[lkml]   [2008]   [Feb]   [25]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
Patch in this message
/
From
Subject[PATCH] Don't risk NULL deref in marker
Date

get_marker() may return NULL, so test for it.


Signed-off-by: Jesper Juhl <jesper.juhl@gmail.com>
---

diff --git a/kernel/marker.c b/kernel/marker.c
index 50effc0..f211f08 100644
--- a/kernel/marker.c
+++ b/kernel/marker.c
@@ -698,12 +698,11 @@ int marker_probe_unregister(const char *name,
{
struct marker_entry *entry;
struct marker_probe_closure *old;
- int ret = 0;
+ int ret = -ENOENT;

mutex_lock(&markers_mutex);
entry = get_marker(name);
if (!entry) {
- ret = -ENOENT;
goto end;
}
if (entry->rcu_pending)
@@ -713,12 +712,16 @@ int marker_probe_unregister(const char *name,
marker_update_probes(); /* may update entry */
mutex_lock(&markers_mutex);
entry = get_marker(name);
+ if (!entry) {
+ goto end;
+ }
entry->oldptr = old;
entry->rcu_pending = 1;
/* write rcu_pending before calling the RCU callback */
smp_wmb();
call_rcu(&entry->rcu, free_old_closure);
remove_marker(name); /* Ignore busy error message */
+ ret = 0;
end:
mutex_unlock(&markers_mutex);
return ret;

\
 
 \ /
  Last update: 2008-02-26 00:23    [W:0.063 / U:0.068 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site