Kmemleak reports the following leak:
unreferenced object 0xfffffbfff41ea000 (size 20480):
comm "modprobe", pid 65199, jiffies 4298875551 (age 542.568s)
hex dump (first 32 bytes):
00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................
00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................
backtrace:
[<ffffffff82354f5e>] kmemleak_alloc+0x4e/0xc0
[<ffffffff8152e718>] __vmalloc_node_range+0x4b8/0x740
[<ffffffff81574072>] kasan_module_alloc+0x72/0xc0
[<ffffffff810efe68>] module_alloc+0x78/0xb0
[<ffffffff812f6a24>] module_alloc_update_bounds+0x14/0x70
[<ffffffff812f8184>] layout_and_allocate+0x16f4/0x3c90
[<ffffffff812faa1f>] load_module+0x2ff/0x6690
[<ffffffff813010b6>] SyS_finit_module+0x136/0x170
[<ffffffff8239bbc9>] system_call_fastpath+0x16/0x1b
[<ffffffffffffffff>] 0xffffffffffffffff
kasan_module_alloc() allocates shadow memory for module and frees it on module
unloading. It doesn't store the pointer to allocated shadow memory because
it could be calculated from the shadowed address, i.e.
kasan_mem_to_shadow(addr).
Since kmemleak cannot find pointer to allocated shadow, it thinks that memory
leaked.
We should tell kmemleak that this is not a leak.
Signed-off-by: Andrey Ryabinin <[email protected]>
---
mm/kasan/kasan.c | 2 ++
1 file changed, 2 insertions(+)
diff --git a/mm/kasan/kasan.c b/mm/kasan/kasan.c
index d41b21b..413b12d 100644
--- a/mm/kasan/kasan.c
+++ b/mm/kasan/kasan.c
@@ -19,6 +19,7 @@
#include <linux/export.h>
#include <linux/init.h>
#include <linux/kernel.h>
+#include <linux/kmemleak.h>
#include <linux/memblock.h>
#include <linux/memory.h>
#include <linux/mm.h>
@@ -444,6 +445,7 @@ int kasan_module_alloc(void *addr, size_t size)
if (ret) {
find_vm_area(addr)->flags |= VM_KASAN;
+ kmemleak_not_leak(ret);
return 0;
}
--
2.4.10
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to [email protected]
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/
