lkml.org 
[lkml]   [2020]   [Dec]   [28]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
    Patch in this message
    /
    From
    Subject[PATCH 5.4 440/453] device-dax/core: Fix memory leak when rmmod dax.ko
    Date
    From: Wang Hai <wanghai38@huawei.com>

    commit 1aa574312518ef1d60d2dc62d58f7021db3b163a upstream.

    When I repeatedly modprobe and rmmod dax.ko, kmemleak report a
    memory leak as follows:

    unreferenced object 0xffff9a5588c05088 (size 8):
    comm "modprobe", pid 261, jiffies 4294693644 (age 42.063s)
    ...
    backtrace:
    [<00000000e007ced0>] kstrdup+0x35/0x70
    [<000000002ae73897>] kstrdup_const+0x3d/0x50
    [<000000002b00c9c3>] kvasprintf_const+0xbc/0xf0
    [<000000008023282f>] kobject_set_name_vargs+0x3b/0xd0
    [<00000000d2cbaa4e>] kobject_set_name+0x62/0x90
    [<00000000202e7a22>] bus_register+0x7f/0x2b0
    [<000000000b77792c>] 0xffffffffc02840f7
    [<000000002d5be5ac>] 0xffffffffc02840b4
    [<00000000dcafb7cd>] do_one_initcall+0x58/0x240
    [<00000000049fe480>] do_init_module+0x56/0x1e2
    [<0000000022671491>] load_module+0x2517/0x2840
    [<000000001a2201cb>] __do_sys_finit_module+0x9c/0xe0
    [<000000003eb304e7>] do_syscall_64+0x33/0x40
    [<0000000051c5fd06>] entry_SYSCALL_64_after_hwframe+0x44/0xa9

    When rmmod dax is executed, dax_bus_exit() is missing. This patch
    can fix this bug.

    Fixes: 9567da0b408a ("device-dax: Introduce bus + driver model")
    Cc: <stable@vger.kernel.org>
    Reported-by: Hulk Robot <hulkci@huawei.com>
    Signed-off-by: Wang Hai <wanghai38@huawei.com>
    Link: https://lore.kernel.org/r/20201201135929.66530-1-wanghai38@huawei.com
    Signed-off-by: Dan Williams <dan.j.williams@intel.com>
    Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

    ---
    drivers/dax/super.c | 1 +
    1 file changed, 1 insertion(+)

    --- a/drivers/dax/super.c
    +++ b/drivers/dax/super.c
    @@ -720,6 +720,7 @@ err_chrdev:

    static void __exit dax_core_exit(void)
    {
    + dax_bus_exit();
    unregister_chrdev_region(dax_devt, MINORMASK+1);
    ida_destroy(&dax_minor_ida);
    dax_fs_exit();

    \
     
     \ /
      Last update: 2020-12-28 15:00    [W:4.050 / U:0.040 seconds]
    ©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site