• Yang Shi's avatar
    locktorture: Fix potential memory leak with rw lock test · f4dbba59
    Yang Shi authored
    When running locktorture module with the below commands with kmemleak enabled:
    
    $ modprobe locktorture torture_type=rw_lock_irq
    $ rmmod locktorture
    
    The below kmemleak got caught:
    
    root@10:~# echo scan > /sys/kernel/debug/kmemleak
    [  323.197029] kmemleak: 2 new suspected memory leaks (see /sys/kernel/debug/kmemleak)
    root@10:~# cat /sys/kernel/debug/kmemleak
    unreferenced object 0xffffffc07592d500 (size 128):
      comm "modprobe", pid 368, jiffies 4294924118 (age 205.824s)
      hex dump (first 32 bytes):
        00 00 00 00 00 00 00 00 c3 7b 02 00 00 00 00 00  .........{......
        00 00 00 00 00 00 00 00 d7 9b 02 00 00 00 00 00  ................
      backtrace:
        [<ffffff80081e5a88>] create_object+0x110/0x288
        [<ffffff80086c6078>] kmemleak_alloc+0x58/0xa0
        [<ffffff80081d5acc>] __kmalloc+0x234/0x318
        [<ffffff80006fa130>] 0xffffff80006fa130
        [<ffffff8008083ae4>] do_one_initcall+0x44/0x138
        [<ffffff800817e28c>] do_init_module+0x68/0x1cc
        [<ffffff800811c848>] load_module+0x1a68/0x22e0
        [<ffffff800811d340>] SyS_finit_module+0xe0/0xf0
        [<ffffff80080836f0>] el0_svc_naked+0x24/0x28
        [<ffffffffffffffff>] 0xffffffffffffffff
    unreferenced object 0xffffffc07592d480 (size 128):
      comm "modprobe", pid 368, jiffies 4294924118 (age 205.824s)
      hex dump (first 32 bytes):
        00 00 00 00 00 00 00 00 3b 6f 01 00 00 00 00 00  ........;o......
        00 00 00 00 00 00 00 00 23 6a 01 00 00 00 00 00  ........#j......
      backtrace:
        [<ffffff80081e5a88>] create_object+0x110/0x288
        [<ffffff80086c6078>] kmemleak_alloc+0x58/0xa0
        [<ffffff80081d5acc>] __kmalloc+0x234/0x318
        [<ffffff80006fa22c>] 0xffffff80006fa22c
        [<ffffff8008083ae4>] do_one_initcall+0x44/0x138
        [<ffffff800817e28c>] do_init_module+0x68/0x1cc
        [<ffffff800811c848>] load_module+0x1a68/0x22e0
        [<ffffff800811d340>] SyS_finit_module+0xe0/0xf0
        [<ffffff80080836f0>] el0_svc_naked+0x24/0x28
        [<ffffffffffffffff>] 0xffffffffffffffff
    
    It is because cxt.lwsa and cxt.lrsa don't get freed in module_exit, so free
    them in lock_torture_cleanup() and free writer_tasks if reader_tasks is
    failed at memory allocation.
    Signed-off-by: default avatarYang Shi <yang.shi@linaro.org>
    Signed-off-by: default avatarPaul E. McKenney <paulmck@linux.vnet.ibm.com>
    Reviewed-by: default avatarJosh Triplett <josh@joshtriplett.org>
    f4dbba59
locktorture.c 26.5 KB