lkdtm: fix memory leak of base

This case is supposed to read from a memory after it has been freed,
but we missed freeing base if the memory 'val' could not be allocated.

Signed-off-by: Sudip Mukherjee <sudip.mukherjee@codethink.co.uk>
Signed-off-by: Kees Cook <keescook@chromium.org>

diff --git a/drivers/misc/lkdtm.c b/drivers/misc/lkdtm.c
index 2f0b022..5b3a63c 100644 (file)
--- a/drivers/misc/lkdtm.c
+++ b/drivers/misc/lkdtm.c
@@ -458,8 +458,10 @@ static void lkdtm_do_action(enum ctype which)
                        break;
 
                val = kmalloc(len, GFP_KERNEL);
-               if (!val)
+               if (!val) {
+                       kfree(base);
                        break;
+               }
 
                *val = 0x12345678;
                base[offset] = *val;