From: Sri Krishna chowdary <schowdary@xxxxxxxxxx>
kmemleak detects allocated objects as leaks if not accessed for
default scan time. The memory allocated using avc_alloc_node
is freed using rcu mechanism when nodes are reclaimed or on
avc_flush. So, there is no real leak here and kmemleak_scan
detects it as a leak which is false positive. Hence, mark it as
kmemleak_not_leak.
Following is the log for avc_alloc_node detected as leak:
unreferenced object 0xffffffc0dd1a0e60 (size 64):
comm "InputDispatcher", pid 648, jiffies 4294944629 (age 698.180s)
hex dump (first 32 bytes):
ed 00 00 00 ed 00 00 00 17 00 00 00 3f fe 41 00 ............?.A.
00 00 00 00 ff ff ff ff 01 00 00 00 00 00 00 00 ................
backtrace:
[<ffffffc000192390>] __save_stack_trace+0x24/0x34
[<ffffffc000192dcc>] create_object+0x13c/0x290
[<ffffffc000b926f0>] kmemleak_alloc+0x80/0xbc
[<ffffffc00018e018>] kmem_cache_alloc+0x128/0x1f8
[<ffffffc000313d40>] avc_alloc_node+0x2c/0x1e8
[<ffffffc000313f34>] avc_insert+0x38/0x13c
[<ffffffc000314084>] avc_compute_av+0x4c/0x60
[<ffffffc00031461c>] avc_has_perm_flags+0x90/0x188
[<ffffffc000319430>] sock_has_perm+0x84/0x98
[<ffffffc0003194e4>] selinux_socket_sendmsg+0x1c/0x28
[<ffffffc000312f58>] security_socket_sendmsg+0x14/0x20
[<ffffffc0009c60c4>] sock_sendmsg+0x70/0xc8
[<ffffffc0009c8884>] SyS_sendto+0x140/0x1ec
[<ffffffc0000853c0>] el0_svc_naked+0x34/0x38
[<ffffffffffffffff>] 0xffffffffffffffff
Signed-off-by: Sri Krishna chowdary <schowdary@xxxxxxxxxx>
Signed-off-by: Prateek <prpatel@xxxxxxxxxx>
---
security/selinux/avc.c | 2 ++
1 file changed, 2 insertions(+)
diff --git a/security/selinux/avc.c b/security/selinux/avc.c
index 635e5c1..ecfd0cd 100644
--- a/security/selinux/avc.c
+++ b/security/selinux/avc.c
@@ -30,6 +30,7 @@
#include <linux/audit.h>
#include <linux/ipv6.h>
#include <net/ipv6.h>
+#include <linux/kmemleak.h>
#include "avc.h"
#include "avc_ss.h"
#include "classmap.h"
@@ -573,6 +574,7 @@ static struct avc_node *avc_alloc_node(struct selinux_avc *avc)
if (!node)
goto out;
+ kmemleak_not_leak(node);
INIT_HLIST_NODE(&node->list);
avc_cache_stats_incr(allocations);
--
2.7.4
